The JZX811A/B ad hoc network module of Techno Core adopts LoRa spread spectrum technology, and its working frequency is integrated with 433MHZ and 490MHZ. Simply setting the channel can complete the conversion of working frequency, which greatly meets the requirements of various application environments and improves the anti-interference ability of the communication system.in other words Wireless Module It is possible to develop in a good direction, and there are still many places worth looking forward to in the future. https://www.hkulike.com/

　　

　　Ad hoc network is a planar peer-to-peer mesh network, and each node in the network can be used as a routing node and a target node. The communication module adopts the company’s self-organizing network protocol, making full use of the redundant routing in the network, and each node has multiple backup paths besides the main path; The network has good self-healing. When the access link between a node and the center fails, the center can automatically start the path repair function of the node.

　　

　　The JZX811 networking network is composed of a coordinator JZX811B(Coordinator) and several nodes JZX811A(Router), and its system structure is shown in the following figure:

　　

　　Technical indicators of JZX811A/B module of Techno Core:

　　

　　1. modulation mode: LoRa;

　　

　　2. Working frequency: 433 MHz/490 MHz;

　　

　　3. Transmitting power: 50mW (17dB);

　　

　　4. Receiving sensitivity:-139 DBM;

　　

　　5. Emission current: 150mA;

　　

　　6. Receiving current: 15mA;

　　

　　7. Dormant current: JZX811A6uA; JZX811B has no dormancy;

　　

　　8. Channel rate: 200/300/600/1200/2400/4800/9600/19200 bit/s;

　　

　　9. Serial port speed: 1200/2400/4800/9600/19200 bit/s;

　　

　　10. Interface type: TTL, RS232, RS485;

　　

　　11. Interface data format: 8E1/8N1/8O1 can be customized by users;

　　

　　12. Working power supply: DC 3.3~5.5V;

　　

　　13. Working temperature:-20≧ ~ 75≧;

　　

　　14. Working humidity: 10% ~ 90% relative humidity, no condensation;

　　

　　15. Maximum number of bytes per packet: 230 bytes;

　　

　　16. Maximum routing level: level 5.

　　The JZX811A/B ad hoc network module of Techno Core adopts LoRa spread spectrum technology, and its working frequency is integrated with 433MHZ and 490MHZ. Simply setting the channel can complete the conversion of working frequency, which greatly meets the requirements of various application environments and improves the anti-interference ability of the communication system.If we can practice these points, Wireless Module Will be unique, become a leader in the industry, and keep moving forward. https://www.hkulike.com/

　　

　　Ad hoc network is a planar peer-to-peer mesh network, and each node in the network can be used as a routing node and a target node. The communication module adopts the company’s self-organizing network protocol, making full use of the redundant routing in the network, and each node has multiple backup paths besides the main path; The network has good self-healing. When the access link between a node and the center fails, the center can automatically start the path repair function of the node.

　　

　　The JZX811 networking network is composed of a coordinator JZX811B(Coordinator) and several nodes JZX811A(Router), and its system structure is shown in the following figure:

　　

　　Technical indicators of JZX811A/B module of Techno Core:

　　

　　1. modulation mode: LoRa;

　　

　　2. Working frequency: 433 MHz/490 MHz;

　　

　　3. Transmitting power: 50mW (17dB);

　　

　　4. Receiving sensitivity:-139 DBM;

　　

　　5. Emission current: 150mA;

　　

　　6. Receiving current: 15mA;

　　

　　7. Dormant current: JZX811A6uA; JZX811B has no dormancy;

　　

　　8. Channel rate: 200/300/600/1200/2400/4800/9600/19200 bit/s;

　　

　　9. Serial port speed: 1200/2400/4800/9600/19200 bit/s;

　　

　　10. Interface type: TTL, RS232, RS485;

　　

　　11. Interface data format: 8E1/8N1/8O1 can be customized by users;

　　

　　12. Working power supply: DC 3.3~5.5V;

　　

　　13. Working temperature:-20≧ ~ 75≧;

　　

　　14. Working humidity: 10% ~ 90% relative humidity, no condensation;

　　

　　15. Maximum number of bytes per packet: 230 bytes;

　　

　　16. Maximum routing level: level 5.

　　The wireless transceiver module is mainly used for signal transmission to achieve multi-functional purposes such as communication and wireless control. General wireless modules are used in a variety of occasions, and the following mainly introduces three kinds.In the eyes of industry experts, RF Module Indeed, it has great development potential, which makes many investors more interested. https://www.hkulike.com/

　　

　　First, used for channel control

　　

　　What is channel control? Channel control is divided into parallel and multi-channel. This kind of control is generally applied to the control of complex remote-controlled robots, and the safety protection control of some places can be controlled and driven by the receiving and sending signals of wireless modules.

　　

　　Second, for the development of wireless communication networks

　　

　　For professionals, the link of wireless communication network needs the application of topological structure, and only with this structure can the application value be realized by using the transceiver system of wireless module. On the one hand, this kind of transmitting and receiving module is cheap, and the cost of forming a star topology is relatively low; On the other hand, the transmitting and receiving module can adopt modular design, which is small in size, convenient to use and easy to integrate. This transmitting and receiving module is very practical for wireless networks with low communication speed and close distance.

　　

　　Third, used for serial data transmission

　　

　　Usually, many control instruments and devices use serial port, and communication with these devices must meet the requirements of serial port, and the transmission rate and electrical characteristics must meet the serial port standard. Some special places, industrial control sites. When it is necessary to use wireless transmission mode, the transmitting and receiving module mentioned in this paper can be naturally selected. However, it must be explained here that in order to adopt this communication method, the corresponding software must be compiled at the transmitter and receiver to realize the file format conversion, so as to achieve the purpose of wireless communication.

　　The working frequency of the wireless transceiver module is 315MHz or 433MHz (there are other special frequencies), and the SAW resonator is used to stabilize the frequency, so the frequency stability is extremely high. When the ambient temperature changes between-25 and+85 degrees, the frequency drift is only 3ppm/ degree. It is especially suitable for wireless remote control and data transmission system. The frequency stability of acoustic resonator is second only to that of crystal, but the frequency stability and consistency of general LC oscillator are poor. Even if high-quality fine-tuning capacitors are used, it is difficult to ensure that the tuned frequency points will not shift due to temperature difference and vibration.It is reported that, RF Module The data performance is getting better and better, which is of great reference value and is likely to become the vane of the industry. https://www.hkulike.com/

　　

　　So how to use the wireless transceiver module correctly? The following small series of Zhuoxin Technology introduces the following three methods.

　　

　　1. It is used to build a wireless communication network with star topology.

　　

　　It must be a multi-point star topology, and some special places need wireless communication. On the one hand, this kind of transmitting and receiving module is cheap, and the cost of forming a star topology is relatively low; On the other hand, the transmitting and receiving module can adopt modular design, which is small in size, convenient to use and easy to integrate. This transmitting and receiving module is very practical for wireless networks with low communication speed and close distance.

　　

　　2. Used for wireless multi-channel (parallel) control

　　

　　Such as complex remote control robots, some places need multi-channel control. One method is that the receiver module is directly connected to the decoder, and then connected to electronic components such as relays to drive the subsequent controlled objects; Another method is to connect the receiving module with the single chip microcomputer, and then connect the relay and other electronic components with the single chip microcomputer after data processing to drive the subsequent controlled objects. Usually, a pair of transmitting and receiving modules can realize six parallel wireless control at most. If the number of channels required is more than six, multiple pairs of transmitting and receiving modules can be used to work at the same time to meet the actual needs.

　　

　　3. Used for universal serial port (C502B) wireless data transmission.

　　

　　Usually, many control instruments and devices use serial port, and communication with these devices must meet the requirements of serial port. Some extraordinary places, industrial control sites. When it is necessary to use wireless transmission mode, the transmitting and receiving module mentioned in this paper can be naturally selected. However, it must be explained here that in order to adopt this communication method, the corresponding software must be compiled at the transmitter and receiver to realize the file format conversion, so as to achieve the purpose of wireless communication. If the communication system is full duplex, two pairs of transmitter and receiver modules can be used to work at the same time.

　　

　　Of course, there are some precautions when using the wireless transceiver module. The transmitting module should be installed vertically on the edge of the motherboard, and should be more than 5mm away from the surrounding devices to avoid being affected by the distribution parameters. The transmission distance of wireless transceiver module is related to modulation signal frequency and amplitude, transmitting voltage and battery capacity, sensitivity of transmitting antenna and receiver, and receiving and transmitting environment.

　　1. List of questions and alliance answers for operators to deploy NB-IoTThrough bit by bit efforts, let RF Module Our market share is getting higher and higher, and the return on investment is also rising steadily. https://www.hkulike.com/

　　

　　How is the network architecture of NB-IoT composed?

　　

　　Building vertical industry application of Internet of Things based on NB-IoT technology will tend to be simpler and the division of labor will be clearer.

　　

　　How do domestic and foreign operators divide the frequency bands of NB-IoT?

　　

　　Most operators in the world use the 900MHz frequency band to deploy NB-IoT, and some operators deploy it in the 800MHz frequency band. China Unicom’s NB-IoT is deployed in 900MHz and 1800MHz frequency bands, and only 900MHz can be tested at present. In order to build the NB-IoT Internet of Things, China Mobile will obtain the FDD license and allow the existing 900MHz and 1800MHz frequency bands to be re-cultivated. China Telecom’s NB-IoT is deployed in the 800MHz band, with a frequency of only 5MHz.

　　

　　NB-IoT network deployment schedule?

　　

　　In 2016, China Unicom launched NB-IoT field-scale networking tests based on 900MHz and 1800MHz in seven cities (Beijing, Shanghai, Guangzhou, Shenzhen, Fuzhou, Changsha and Yinchuan), as well as more than six business application demonstrations. In 2018, the commercial deployment of NB-IoT will be fully promoted nationwide. China Mobile plans to start the commercialization of NB-IoT in 2017. China Telecom plans to deploy NB-IoT network in the first half of 2017. Huawei and six operators (China Unicom, China Mobile, Vodafone, Emirates Telecom, Telefonica and Italia Telecom) set up six NB-IoT open laboratories around the world, focusing on NB-IoT business innovation, industry development, interoperability testing and product compatibility verification. ZTE and China Mobile completed the technical verification demonstration of NB-IoT protocol in the laboratory of China Mobile’s 5G Joint Innovation Center.

　　

　　Can non-operators deploy NB-IoT networks?

　　

　　The answer is no.

　　

　　Does NB-IoT need real-name registration system?

　　

　　All needs, tracked to the responsible subject.

　　

　　Does NB-IoT all adopt eSIM?

　　

　　The product features of NB-IoT are that it can work without installation and configuration, and it can be directly connected to the network by booting, and it supports functions such as automatic equipment registration and air upgrade. SIM card and eSIM will coexist for a long time, and operators refuse the soft SIM mode.

　　

　　What is the operator’s plan to quit the 2G/3G network?

　　

　　China Unicom may gradually close its 2G network in 2018, and in some places it may close its 3G network. Japan’s mobile operators have all shut down 2G networks, and AT&T in the United States, Telstra and Optus in Australia have announced plans to shut down 2G networks. Telenor plans to close its 3G network in Norway in 2020, followed by its 2G network in 2025. Some operators consider that there are more than 100 million GPRS IOT terminals and low-end GSM mobile phones for a long time, and the cost of GSM is lower than that of LTE for a long time because of its low complexity and no patent fees. Therefore, most operators will maintain the GSM frequency band to continue their operations for a long time.

　　

　　Do operators support NB-IoT roaming?

　　

　　The answer is no.

　　

　　How can operators ensure the stability of NB-IoT network?

　　

　　NB-IoT is directly deployed in GSM, UMTS or LTE networks, which can be reused with existing network base stations to reduce deployment costs and achieve smooth upgrade. However, the use of a separate 180KHz frequency band does not occupy the voice and data bandwidth of existing networks, ensuring that traditional services and future Internet of Things services can be carried out stably and reliably at the same time.

　　

　　The control and bearer of NB-IoT are separated, with signaling on the control plane and data on the bearer plane. If it is a low-rate service, it goes directly to the control plane, and no dedicated bearer is established, which omits the signaling process of establishing a link between NAS and the core network and shortens the wake-up recovery delay. NB-IoT is an operational telecommunications network. This is the key to distinguish NB-IoT from GPRS, LoRa, SigFox and other technologies.

　　

　　How can operators make use of NB-IoT network to make profits?

　　

　　Operators’ existing areas such as QoS service quality assurance, network security, telecom-level billing and big data services continue to maintain their industry advantages. NB-IoT network allows operators to strengthen their business service capabilities in the field of Internet of Things, including cloud service provision, mass customer management, real-name authentication of Internet of Things, system general contracting integration, and high-end customized services for large customers.

　　

　　Price issues related to NB-IoT?

　　

　　Operator’s charges: one is based on flow and the other is based on message, and the trend will be lower than the price of GPRS cost chip: lower than the price of 2G main chip, with a reasonable expected price of $1. Module price: lower than the price of GPRS module, with a reasonable expected price of $2. Terminal price: pricing maintenance cost according to actual function: far lower than the existing network maintenance cost subsidy policy: operators will provide larger operating subsidies in the early stage.

　　

　　2. List of questions and answers about NB-IoT technology.

　　

　　Will NB-IoT standard support TDD LTE?

　　

　　At present, FDD LTE system supports NB-IoT technology, while TDD LTE system does not support NB-IoT technology. The physical layer design of NB-IoT mostly follows LTE system technology, such as SC-FDMA for uplink and OFDM for downlink. The design of high-level protocol follows LTE protocol, and its function is enhanced according to its small data packet, low power consumption and large connection characteristics. The core network is connected based on S1 interface, which supports independent deployment and upgrade deployment.

　　

　　Does NB-IoT support base station positioning?

　　

　　R13 does not support base station location, but the operator network can do private solutions, such as location based on cell ID, which will not affect the terminal, and only need the network to increase the location server and contact with the base station. R14 plans to enhance positioning, supporting E-CID, UTDOA or OTDOA, and the operator’s desired positioning accuracy target is within 50 meters.

　　

　　Considering the terminal complexity, UTDOA is better, because it has little influence on the terminal, and in the case of enhanced coverage (basement 164dB), UTDOA (uplink) power consumption is lower; If coverage enhancement is not needed in most scenarios, OTDOA (downlink) will be better from the perspective of network capacity.

　　

　　What are the deployment methods of NB-IoT?

　　

　　NB-IoT supports three different deployment modes, namely independent deployment, guard band deployment and in-band deployment. Independent deployment: A separate frequency band can be used, which is suitable for re-cultivation in GSM frequency band. Guard band deployment: The marginal useless frequency band in LTE system can be utilized. In-band deployment: Any resource block in the middle of LTE carrier can be utilized.

　　

　　What modulation and demodulation technology does NB-IoT use?

　　

　　OFDMA is used for downlink, and the subcarrier spacing is 15kHz. The uplink adopts SC-FDMA, single-tone: 3.75kHz/15kHz, and multi-tone: 15kHz. Only need to support half duplex, with a separate synchronization signal. The terminal supports the indication of Single-tone and Multi-tone capabilities. The MAC/RLC/PDCP/RRC layer processing is based on the existing LTE processes and protocols, and the physical layer is optimized.

　　

　　What are the number of connected users and active users of NB-IoT base station?

　　

　　NB-IoT has 50-100 times the uplink capacity improvement compared with 2G/3G/4G, and NB-IoT can provide 50-100 times the access number compared with the existing wireless technology under the same base station. Under the frequency of 200KHz, according to the simulation test data, a single base station cell can support 50,000 NB-IoT terminals to access.

　　

　　What is the coverage of NB-IoT base station?

　　

　　NB-IoT has a gain of 20dB higher than that of LTE and GPRS base stations, and it is expected to cover underground garages, basements, underground pipelines and other places where signals are difficult to reach. According to the simulation test data, in the independent deployment mode, the coverage capacity of NB-IoT can reach 164dB, and the in-band deployment and guard band deployment need to be simulated and tested.

　　

　　What is the uplink and downlink transmission rate of NB-IoT?

　　

　　NB-IoT RF bandwidth is 200kHz. Downlink rate: greater than 160kbps and less than 250kbps. Uplink rate: greater than 160kbps and less than 250 kbps (multi-tone)/200 kbps (single-tone).

　　

　　Does NB-IoT support retransmission mechanism?

　　

　　NB-IoT adopts retransmission (up to 200 times) and low-order modulation to enhance coverage.

　　

　　Does NB-IoT support voice?

　　

　　NB-IoT supports Push to Talk without coverage enhancement. In the scenario of enhanced coverage of 20dB, only similar voicemails can be supported. NB-IoT does not support VoLTE, which requires too high delay, and the high-level protocol stack needs QoS guarantee, which will increase the cost.

　　

　　Why does the chip of NB-IoT consume low power?

　　

　　The energy consumed by a device is related to the amount or rate of data, and the size of data packets sent per unit time determines the size of power consumption. NB-IoT introduces eDRX power saving technology and PSM power saving mode, which further reduces power consumption and prolongs battery life. NB-IoT can keep devices online all the time, but it can save power by reducing unnecessary signaling and not accepting paging information when in PSM state.

　　

　　In PSM mode, the terminal is still registered in the network, but the signaling is unreachable, which makes the terminal stay in deep sleep for a longer time to save electricity. EDRX power saving technology further prolongs the sleep period of the terminal in idle mode, reduces unnecessary startup of the receiving unit, and greatly improves the downlink accessibility compared with PSM.

　　

　　Does NB-IoT sleep wake-up mode affect battery life?

　　

　　At present, the working time given by NB-IoT is based on simulation data, without considering the battery itself and environmental factors, such as self-discharge and aging of the battery, high and low temperature environmental impact, etc. In actual use, it is necessary to comprehensively evaluate the power supply time of the battery according to the actual situation. NB-IoT adopts the power-saving scheme of sleep wake-up. When the battery is awakened during sleep, it will receive instantaneous strong current, which will greatly affect the battery life. The application of meter reading usually adopts lithium thionyl chloride (Li/SOCl2) battery and super capacitor. Consumer electronics and others should be powered by li-polymer.

　　

　　Why are NB-IoT chips cheap?

　　

　　Low speed, low power consumption and low bandwidth bring low cost advantages. Low speed: it means that no large cache is needed, so the cache can be small and the DSP configuration is low; Low power consumption: it means that RF design requirements are low, and small PA can be realized; Low bandwidth: It means that there is no need for complicated equalization algorithm … These factors make the NB-IoT chip small, so the cost will be reduced.

　　

　　Taking a certain chip as an example, NB-IoT chip integrates BB, AP, Flash and battery management, and reserves the function of sensor set. The AP includes three ARM-M0 cores, and each M0 core is responsible for the application, security and communication functions respectively, which facilitates the function management and reduces the cost and power consumption.

　　

　　What is the range of NB-IoT to the device movement rate?

　　

　　NB-IoT is suitable for application scenarios with weak mobility support (such as intelligent meter reading, intelligent parking, etc.), while simplifying the complexity of the terminal and reducing the power consumption of the terminal. NB-IoT does not support mobility management in connected state, including related measurement, measurement report, handover, etc.

　　

　　What is the network delay of NB-IoT?

　　

　　NB-IoT allows a delay of about 10s, but it can support a lower delay, such as about 6s, in the environment of maximum coupling loss.

　　

　　3. Deployment of NB-IoT technology in various vertical application fields of the Internet of Things.

　　

　　What is the deployment cost of NB-IoT vertical application?

　　

　　The deployment cost of NB-IoT vertical application field includes hardware cost, network cost, installation cost and service cost. If we want to realize the scale of application field, we must reduce the deployment cost.

　　

　　What is the focus of NB-IoT in vertical application field?

　　

　　NB-IoT technology can meet the requirements of low-rate services with low power consumption, long standby, deep coverage and large capacity, and is more suitable for static services, low sensitivity to time delay, discontinuous movement and real-time data transmission. 1. Autonomous anomaly reporting business types: such as smoke alarm detectors, abnormal equipment operation, etc. The uplink data volume is extremely small (on the order of ten bytes), and the cycle is mostly in years and months. 2. Business types of autonomous periodic reporting: such as remote meter reading of public utilities and environmental monitoring, etc. The uplink data volume is small (on the order of 100 bytes), and the cycle is mostly in days and hours. 3. Service type of remote control instruction:

　　

　　For example, if the equipment is turned on/off remotely, and the equipment triggers to send an uplink report, the downlink data amount is very small (on the order of ten bytes), and the cycle is mostly in days and hours. 4. Software remote update service type: such as software patch/update, and the uplink and downlink need a large amount of data (kilobyte level), and the cycle is mostly in days and hours.

　　1. List of questions and alliance answers for operators to deploy NB-IoTIn order to achieve the goal, Wireless Module Turn cocoon into butterfly, constantly polish product quality, improve business ability, and finally have a place in the market. https://www.hkulike.com/

　　

　　How is the network architecture of NB-IoT composed?

　　

　　Building vertical industry application of Internet of Things based on NB-IoT technology will tend to be simpler and the division of labor will be clearer.

　　

　　How do domestic and foreign operators divide the frequency bands of NB-IoT?

　　

　　Most operators in the world use the 900MHz frequency band to deploy NB-IoT, and some operators deploy it in the 800MHz frequency band. China Unicom’s NB-IoT is deployed in 900MHz and 1800MHz frequency bands, and only 900MHz can be tested at present. In order to build the NB-IoT Internet of Things, China Mobile will obtain the FDD license and allow the existing 900MHz and 1800MHz frequency bands to be re-cultivated. China Telecom’s NB-IoT is deployed in the 800MHz band, with a frequency of only 5MHz.

　　

　　NB-IoT network deployment schedule?

　　

　　In 2016, China Unicom launched NB-IoT field-scale networking tests based on 900MHz and 1800MHz in seven cities (Beijing, Shanghai, Guangzhou, Shenzhen, Fuzhou, Changsha and Yinchuan), as well as more than six business application demonstrations. In 2018, the commercial deployment of NB-IoT will be fully promoted nationwide. China Mobile plans to start the commercialization of NB-IoT in 2017. China Telecom plans to deploy NB-IoT network in the first half of 2017. Huawei and six operators (China Unicom, China Mobile, Vodafone, Emirates Telecom, Telefonica and Italia Telecom) set up six NB-IoT open laboratories around the world, focusing on NB-IoT business innovation, industry development, interoperability testing and product compatibility verification. ZTE and China Mobile completed the technical verification demonstration of NB-IoT protocol in the laboratory of China Mobile’s 5G Joint Innovation Center.

　　

　　Can non-operators deploy NB-IoT networks?

　　

　　The answer is no.

　　

　　Does NB-IoT need real-name registration system?

　　

　　All needs, tracked to the responsible subject.

　　

　　Does NB-IoT all adopt eSIM?

　　

　　The product features of NB-IoT are that it can work without installation and configuration, and it can be directly connected to the network by booting, and it supports functions such as automatic equipment registration and air upgrade. SIM card and eSIM will coexist for a long time, and operators refuse the soft SIM mode.

　　

　　What is the operator’s plan to quit the 2G/3G network?

　　

　　China Unicom may gradually close its 2G network in 2018, and in some places it may close its 3G network. Japan’s mobile operators have all shut down 2G networks, and AT&T in the United States, Telstra and Optus in Australia have announced plans to shut down 2G networks. Telenor plans to close its 3G network in Norway in 2020, followed by its 2G network in 2025. Some operators consider that there are more than 100 million GPRS IOT terminals and low-end GSM mobile phones for a long time, and the cost of GSM is lower than that of LTE for a long time because of its low complexity and no patent fees. Therefore, most operators will maintain the GSM frequency band to continue their operations for a long time.

　　

　　Do operators support NB-IoT roaming?

　　

　　The answer is no.

　　

　　How can operators ensure the stability of NB-IoT network?

　　

　　NB-IoT is directly deployed in GSM, UMTS or LTE networks, which can be reused with existing network base stations to reduce deployment costs and achieve smooth upgrade. However, the use of a separate 180KHz frequency band does not occupy the voice and data bandwidth of existing networks, ensuring that traditional services and future Internet of Things services can be carried out stably and reliably at the same time.

　　

　　The control and bearer of NB-IoT are separated, with signaling on the control plane and data on the bearer plane. If it is a low-rate service, it goes directly to the control plane, and no dedicated bearer is established, which omits the signaling process of establishing a link between NAS and the core network and shortens the wake-up recovery delay. NB-IoT is an operational telecommunications network. This is the key to distinguish NB-IoT from GPRS, LoRa, SigFox and other technologies.

　　

　　How can operators make use of NB-IoT network to make profits?

　　

　　Operators’ existing areas such as QoS service quality assurance, network security, telecom-level billing and big data services continue to maintain their industry advantages. NB-IoT network allows operators to strengthen their business service capabilities in the field of Internet of Things, including cloud service provision, mass customer management, real-name authentication of Internet of Things, system general contracting integration, and high-end customized services for large customers.

　　

　　Price issues related to NB-IoT?

　　

　　Operator’s charges: one is based on flow and the other is based on message, and the trend will be lower than the price of GPRS cost chip: lower than the price of 2G main chip, with a reasonable expected price of $1. Module price: lower than the price of GPRS module, with a reasonable expected price of $2. Terminal price: pricing maintenance cost according to actual function: far lower than the existing network maintenance cost subsidy policy: operators will provide larger operating subsidies in the early stage.

　　

　　2. List of questions and answers about NB-IoT technology.

　　

　　Will NB-IoT standard support TDD LTE?

　　

　　At present, FDD LTE system supports NB-IoT technology, while TDD LTE system does not support NB-IoT technology. The physical layer design of NB-IoT mostly follows LTE system technology, such as SC-FDMA for uplink and OFDM for downlink. The design of high-level protocol follows LTE protocol, and its function is enhanced according to its small data packet, low power consumption and large connection characteristics. The core network is connected based on S1 interface, which supports independent deployment and upgrade deployment.

　　

　　Does NB-IoT support base station positioning?

　　

　　R13 does not support base station location, but the operator network can do private solutions, such as location based on cell ID, which will not affect the terminal, and only need the network to increase the location server and contact with the base station. R14 plans to enhance positioning, supporting E-CID, UTDOA or OTDOA, and the operator’s desired positioning accuracy target is within 50 meters.

　　

　　Considering the terminal complexity, UTDOA is better, because it has little influence on the terminal, and in the case of enhanced coverage (basement 164dB), UTDOA (uplink) power consumption is lower; If coverage enhancement is not needed in most scenarios, OTDOA (downlink) will be better from the perspective of network capacity.

　　

　　What are the deployment methods of NB-IoT?

　　

　　NB-IoT supports three different deployment modes, namely independent deployment, guard band deployment and in-band deployment. Independent deployment: A separate frequency band can be used, which is suitable for re-cultivation in GSM frequency band. Guard band deployment: The marginal useless frequency band in LTE system can be utilized. In-band deployment: Any resource block in the middle of LTE carrier can be utilized.

　　

　　What modulation and demodulation technology does NB-IoT use?

　　

　　OFDMA is used for downlink, and the subcarrier spacing is 15kHz. The uplink adopts SC-FDMA, single-tone: 3.75kHz/15kHz, and multi-tone: 15kHz. Only need to support half duplex, with a separate synchronization signal. The terminal supports the indication of Single-tone and Multi-tone capabilities. The MAC/RLC/PDCP/RRC layer processing is based on the existing LTE processes and protocols, and the physical layer is optimized.

　　

　　What are the number of connected users and active users of NB-IoT base station?

　　

　　NB-IoT has 50-100 times the uplink capacity improvement compared with 2G/3G/4G, and NB-IoT can provide 50-100 times the access number compared with the existing wireless technology under the same base station. Under the frequency of 200KHz, according to the simulation test data, a single base station cell can support 50,000 NB-IoT terminals to access.

　　

　　What is the coverage of NB-IoT base station?

　　

　　NB-IoT has a gain of 20dB higher than that of LTE and GPRS base stations, and it is expected to cover underground garages, basements, underground pipelines and other places where signals are difficult to reach. According to the simulation test data, in the independent deployment mode, the coverage capacity of NB-IoT can reach 164dB, and the in-band deployment and guard band deployment need to be simulated and tested.

　　

　　What is the uplink and downlink transmission rate of NB-IoT?

　　

　　NB-IoT RF bandwidth is 200kHz. Downlink rate: greater than 160kbps and less than 250kbps. Uplink rate: greater than 160kbps and less than 250 kbps (multi-tone)/200 kbps (single-tone).

　　

　　Does NB-IoT support retransmission mechanism?

　　

　　NB-IoT adopts retransmission (up to 200 times) and low-order modulation to enhance coverage.

　　

　　Does NB-IoT support voice?

　　

　　NB-IoT supports Push to Talk without coverage enhancement. In the scenario of enhanced coverage of 20dB, only similar voicemails can be supported. NB-IoT does not support VoLTE, which requires too high delay, and the high-level protocol stack needs QoS guarantee, which will increase the cost.

　　

　　Why does the chip of NB-IoT consume low power?

　　

　　The energy consumed by a device is related to the amount or rate of data, and the size of data packets sent per unit time determines the size of power consumption. NB-IoT introduces eDRX power saving technology and PSM power saving mode, which further reduces power consumption and prolongs battery life. NB-IoT can keep devices online all the time, but it can save power by reducing unnecessary signaling and not accepting paging information when in PSM state.

　　

　　In PSM mode, the terminal is still registered in the network, but the signaling is unreachable, which makes the terminal stay in deep sleep for a longer time to save electricity. EDRX power saving technology further prolongs the sleep period of the terminal in idle mode, reduces unnecessary startup of the receiving unit, and greatly improves the downlink accessibility compared with PSM.

　　

　　Does NB-IoT sleep wake-up mode affect battery life?

　　

　　At present, the working time given by NB-IoT is based on simulation data, without considering the battery itself and environmental factors, such as self-discharge and aging of the battery, high and low temperature environmental impact, etc. In actual use, it is necessary to comprehensively evaluate the power supply time of the battery according to the actual situation. NB-IoT adopts the power-saving scheme of sleep wake-up. When the battery is awakened during sleep, it will receive instantaneous strong current, which will greatly affect the battery life. The application of meter reading usually adopts lithium thionyl chloride (Li/SOCl2) battery and super capacitor. Consumer electronics and others should be powered by li-polymer.

　　

　　Why are NB-IoT chips cheap?

　　

　　Low speed, low power consumption and low bandwidth bring low cost advantages. Low speed: it means that no large cache is needed, so the cache can be small and the DSP configuration is low; Low power consumption: it means that RF design requirements are low, and small PA can be realized; Low bandwidth: It means that there is no need for complicated equalization algorithm … These factors make the NB-IoT chip small, so the cost will be reduced.

　　

　　Taking a certain chip as an example, NB-IoT chip integrates BB, AP, Flash and battery management, and reserves the function of sensor set. The AP includes three ARM-M0 cores, and each M0 core is responsible for the application, security and communication functions respectively, which facilitates the function management and reduces the cost and power consumption.

　　

　　What is the range of NB-IoT to the device movement rate?

　　

　　NB-IoT is suitable for application scenarios with weak mobility support (such as intelligent meter reading, intelligent parking, etc.), while simplifying the complexity of the terminal and reducing the power consumption of the terminal. NB-IoT does not support mobility management in connected state, including related measurement, measurement report, handover, etc.

　　

　　What is the network delay of NB-IoT?

　　

　　NB-IoT allows a delay of about 10s, but it can support a lower delay, such as about 6s, in the environment of maximum coupling loss.

　　

　　3. Deployment of NB-IoT technology in various vertical application fields of the Internet of Things.

　　

　　What is the deployment cost of NB-IoT vertical application?

　　

　　The deployment cost of NB-IoT vertical application field includes hardware cost, network cost, installation cost and service cost. If we want to realize the scale of application field, we must reduce the deployment cost.

　　

　　What is the focus of NB-IoT in vertical application field?

　　

　　NB-IoT technology can meet the requirements of low-rate services with low power consumption, long standby, deep coverage and large capacity, and is more suitable for static services, low sensitivity to time delay, discontinuous movement and real-time data transmission. 1. Autonomous anomaly reporting business types: such as smoke alarm detectors, abnormal equipment operation, etc. The uplink data volume is extremely small (on the order of ten bytes), and the cycle is mostly in years and months. 2. Business types of autonomous periodic reporting: such as remote meter reading of public utilities and environmental monitoring, etc. The uplink data volume is small (on the order of 100 bytes), and the cycle is mostly in days and hours. 3. Service type of remote control instruction:

　　

　　For example, if the equipment is turned on/off remotely, and the equipment triggers to send an uplink report, the downlink data amount is very small (on the order of ten bytes), and the cycle is mostly in days and hours. 4. Software remote update service type: such as software patch/update, and the uplink and downlink need a large amount of data (kilobyte level), and the cycle is mostly in days and hours.

　　Application process of RTK radio network modeIn view of the actual needs of society, radio Module We need to change some original problems to better serve the society and benefit people. https://www.hkulike.com/

　　

　　1, instrument erection

　　

　　Complete the hardware erection and configuration of the reference station and mobile station, and build the hardware environment for the operation.

　　

　　2. New projects

　　

　　Create engineering, configure basic information such as parameters and coordinates, and complete the data foundation needed for the operation.

　　

　　3. Find the conversion parameters

　　

　　Match the plane coordinates required by the project with the default latitude and longitude coordinates, and directly obtain the required target reference frame coordinates in the operation. /4, single point correction

　　

　　Input the known plane coordinates of the measuring point and correct the parameter differences between different coordinate systems. (It can be skipped after parameter calculation, but it needs to be corrected every time the base station restarts.)

　　

　　4. Check the known points

　　

　　Measure at known points to confirm whether the parameter transformation between different coordinate systems is accurate and effective.

　　

　　5, measurement and lofting

　　

　　Carry out survey or lofting operations in the operation area to obtain the target results.

　　

　　6. Data export

　　

　　Export data from the notebook and copy it to the computer for office processing.

　　

　　Use process of RTK radio mode

　　

　　1, the erection of reference stations

　　

　　Load the battery and turn it on.

　　

　　Open the project star in the notebook and connect to the host through the Bluetooth Manager.

　　

　　Use “Host Settings” to set the host as “base station” and the host data link as “radio station”, set the corresponding radio channel, select the appropriate data format (such as RTCM32) in “Reference Station Settings”, and click “Start the base station” after obtaining the coordinates of the base station.

　　

　　When the data light flashes every second, it indicates that the reference station has been started successfully.

　　

　　2. Set up the mobile station

　　

　　Similar to the reference station, the host is set as “mobile station” and the host data link is set as “radio station”, and the radio channel corresponding to the reference station is set.

　　

　　When the data light of the mobile station flashes every second and reaches a fixed solution, it indicates that the mobile station is working normally.

　　

　　3. Parameter setting

　　

　　New Project: After the solution status is fixed, click “Project” and “New Project” and enter the project name.

　　

　　Antenna Height Setting: Click “Configuration” and “Engineering Settings” and enter the correct antenna height.

　　

　　Coordinate System Settings: Click Configure, Coordinate System Settings and Add, and enter the name of the parameter system (set at will). Select the ellipsoid name as required, and enter the actual local central meridian, and use the default values for other parameters.

　　

　　4. Find the conversion parameters

　　

　　Click “Measure” and “Point Measure” to collect the coordinate information of two known points A1 and A2 in turn.

　　

　　Click “Input”, “Calculation of Conversion Parameters” and “Add”, input the known plane coordinates of point A1, “OK” and “Select a point from the coordinate management library”, select the newly measured point A1, then complete the entry of point A2 in the same way, click “Save”, enter a user-defined file name, and click “Apply” after checking that the horizontal and elevation accuracy are correct, and then assign the parameter values to the current project.

　　

　　After the conversion is completed, the information of the third known point A3 is collected for verification.

　　

　　5, single point correction

　　

　　Every time the reference station is restarted, the mobile station should make a single point correction.

　　

　　Click “Input”, “Calibration Wizard” and “Reference Station Erected at Unknown Point” to erect the mobile station at a known control point. Enter the known plane coordinates and pole height of the mobile station, click “Calibration” and “OK” after the bubble is centered, and the calibration work is completed. After the calibration is completed, it should be checked at another known control point.

　　

　　6. Measure

　　

　　After completing the above steps, point measurement and lofting can be carried out.

　　

　　Application process of RTK radio network mode

　　

　　1, the erection of reference stations

　　

　　Insert the SIM card, load the battery, and start the machine.

　　

　　Open the project star in the notebook and connect to the host through the Bluetooth Manager.

　　

　　Use “Host Settings” to set the host as “base station” and the host data link as “network”.

　　

　　Set the network mode. Customize “Host Settings”, “Network Settings”, “Add” and “Name”, select EAGLE for “Mode”, GPGGA/CDMA for “Connection”, fill in cmnet for “APN”, enter the IP address and corresponding port, set the user name and password, and generally set the access point as the base station host body number to facilitate identification and prevent duplication. Click “OK” after setting.

　　

　　Select an appropriate data format (such as RTCM32) in “Reference Station Settings”, click “Start Base Station” after obtaining the coordinates of the base station, and when the data light flashes every second, it indicates that the reference station has been started successfully.

　　

　　2. Set up the mobile station

　　

　　In a way similar to the base station, set the host as a mobile station and the data link of the host as a network. According to the setting of the base station, select “NTRIP-UDS” as the Mode, enter the corresponding IP address, port, user name, password and access point, and click “OK” and “Connect” until the GPGGA data is successfully uploaded.

　　

　　When the data light of the mobile station flashes every second and reaches a fixed solution, it indicates that the mobile station is working normally.

　　

　　3. Parameter setting

　　

　　New Project: After the solution status is fixed, click “Project” and “New Project” and enter the project name.

　　

　　Antenna Height Setting: Click “Configuration” and “Engineering Settings” and enter the correct antenna height.

　　

　　Coordinate System Settings: Click Configure, Coordinate System Settings and Add, and enter the name of the parameter system (set at will). Select the ellipsoid name as required, and enter the actual local central meridian, and use the default values for other parameters.

　　

　　4. Find the conversion parameters

　　

　　Click “Measure” and “Point Measure” to collect the coordinate information of two known points A1 and A2 in turn.

　　

　　Click “Input”, “Calculation of Conversion Parameters” and “Add”, input the known plane coordinates of point A1, “OK” and “Select a point from the coordinate management library”, select the newly measured point A1, then complete the entry of point A2 in the same way, click “Save”, enter a user-defined file name, and click “Apply” after checking that the horizontal and elevation accuracy are correct, and then assign the parameter values to the current project.

　　

　　After the conversion is completed, the information of the third known point A3 is collected for verification.

　　

　　5, single point correction

　　

　　Every time the reference station is restarted, the mobile station should make a single point correction.

　　

　　Click “Input”, “Calibration Wizard” and “Reference Station Erected at Unknown Point” to erect the mobile station at a known control point. Enter the known plane coordinates and pole height of the mobile station, click “Calibration” and “OK” after the bubble is centered, and the calibration work is completed. After the calibration is completed, it should be checked at another known control point.

　　

　　6. Measure

　　

　　After completing the above steps, RTK radio station can carry out point measurement and lofting.

　　1. List of questions and alliance answers for operators to deploy NB-IoTIn the past ten years, radio Module Defeated many competitors, courageously advanced in the struggle, and polished many good products for customers. https://www.hkulike.com/

　　

　　How is the network architecture of NB-IoT composed?

　　

　　Building vertical industry application of Internet of Things based on NB-IoT technology will tend to be simpler and the division of labor will be clearer.

　　

　　How do domestic and foreign operators divide the frequency bands of NB-IoT?

　　

　　Most operators in the world use the 900MHz frequency band to deploy NB-IoT, and some operators deploy it in the 800MHz frequency band. China Unicom’s NB-IoT is deployed in 900MHz and 1800MHz frequency bands, and only 900MHz can be tested at present. In order to build the NB-IoT Internet of Things, China Mobile will obtain the FDD license and allow the existing 900MHz and 1800MHz frequency bands to be re-cultivated. China Telecom’s NB-IoT is deployed in the 800MHz band, with a frequency of only 5MHz.

　　

　　NB-IoT network deployment schedule?

　　

　　In 2016, China Unicom launched NB-IoT field-scale networking tests based on 900MHz and 1800MHz in seven cities (Beijing, Shanghai, Guangzhou, Shenzhen, Fuzhou, Changsha and Yinchuan), as well as more than six business application demonstrations. In 2018, the commercial deployment of NB-IoT will be fully promoted nationwide. China Mobile plans to start the commercialization of NB-IoT in 2017. China Telecom plans to deploy NB-IoT network in the first half of 2017. Huawei and six operators (China Unicom, China Mobile, Vodafone, Emirates Telecom, Telefonica and Italia Telecom) set up six NB-IoT open laboratories around the world, focusing on NB-IoT business innovation, industry development, interoperability testing and product compatibility verification. ZTE and China Mobile completed the technical verification demonstration of NB-IoT protocol in the laboratory of China Mobile’s 5G Joint Innovation Center.

　　

　　Can non-operators deploy NB-IoT networks?

　　

　　The answer is no.

　　

　　Does NB-IoT need real-name registration system?

　　

　　All needs, tracked to the responsible subject.

　　

　　Does NB-IoT all adopt eSIM?

　　

　　The product features of NB-IoT are that it can work without installation and configuration, and it can be directly connected to the network by booting, and it supports functions such as automatic equipment registration and air upgrade. SIM card and eSIM will coexist for a long time, and operators refuse the soft SIM mode.

　　

　　What is the operator’s plan to quit the 2G/3G network?

　　

　　China Unicom may gradually close its 2G network in 2018, and in some places it may close its 3G network. Japan’s mobile operators have all shut down 2G networks, and AT&T in the United States, Telstra and Optus in Australia have announced plans to shut down 2G networks. Telenor plans to close its 3G network in Norway in 2020, followed by its 2G network in 2025. Some operators consider that there are more than 100 million GPRS IOT terminals and low-end GSM mobile phones for a long time, and the cost of GSM is lower than that of LTE for a long time because of its low complexity and no patent fees. Therefore, most operators will maintain the GSM frequency band to continue their operations for a long time.

　　

　　Do operators support NB-IoT roaming?

　　

　　The answer is no.

　　

　　How can operators ensure the stability of NB-IoT network?

　　

　　NB-IoT is directly deployed in GSM, UMTS or LTE networks, which can be reused with existing network base stations to reduce deployment costs and achieve smooth upgrade. However, the use of a separate 180KHz frequency band does not occupy the voice and data bandwidth of existing networks, ensuring that traditional services and future Internet of Things services can be carried out stably and reliably at the same time.

　　

　　The control and bearer of NB-IoT are separated, with signaling on the control plane and data on the bearer plane. If it is a low-rate service, it goes directly to the control plane, and no dedicated bearer is established, which omits the signaling process of establishing a link between NAS and the core network and shortens the wake-up recovery delay. NB-IoT is an operational telecommunications network. This is the key to distinguish NB-IoT from GPRS, LoRa, SigFox and other technologies.

　　

　　How can operators make use of NB-IoT network to make profits?

　　

　　Operators’ existing areas such as QoS service quality assurance, network security, telecom-level billing and big data services continue to maintain their industry advantages. NB-IoT network allows operators to strengthen their business service capabilities in the field of Internet of Things, including cloud service provision, mass customer management, real-name authentication of Internet of Things, system general contracting integration, and high-end customized services for large customers.

　　

　　Price issues related to NB-IoT?

　　

　　Operator’s charges: one is based on flow and the other is based on message, and the trend will be lower than the price of GPRS cost chip: lower than the price of 2G main chip, with a reasonable expected price of $1. Module price: lower than the price of GPRS module, with a reasonable expected price of $2. Terminal price: pricing maintenance cost according to actual function: far lower than the existing network maintenance cost subsidy policy: operators will provide larger operating subsidies in the early stage.

　　

　　2. List of questions and answers about NB-IoT technology.

　　

　　Will NB-IoT standard support TDD LTE?

　　

　　At present, FDD LTE system supports NB-IoT technology, while TDD LTE system does not support NB-IoT technology. The physical layer design of NB-IoT mostly follows LTE system technology, such as SC-FDMA for uplink and OFDM for downlink. The design of high-level protocol follows LTE protocol, and its function is enhanced according to its small data packet, low power consumption and large connection characteristics. The core network is connected based on S1 interface, which supports independent deployment and upgrade deployment.

　　

　　Does NB-IoT support base station positioning?

　　

　　R13 does not support base station location, but the operator network can do private solutions, such as location based on cell ID, which will not affect the terminal, and only need the network to increase the location server and contact with the base station. R14 plans to enhance positioning, supporting E-CID, UTDOA or OTDOA, and the operator’s desired positioning accuracy target is within 50 meters.

　　

　　Considering the terminal complexity, UTDOA is better, because it has little influence on the terminal, and in the case of enhanced coverage (basement 164dB), UTDOA (uplink) power consumption is lower; If coverage enhancement is not needed in most scenarios, OTDOA (downlink) will be better from the perspective of network capacity.

　　

　　What are the deployment methods of NB-IoT?

　　

　　NB-IoT supports three different deployment modes, namely independent deployment, guard band deployment and in-band deployment. Independent deployment: A separate frequency band can be used, which is suitable for re-cultivation in GSM frequency band. Guard band deployment: The marginal useless frequency band in LTE system can be utilized. In-band deployment: Any resource block in the middle of LTE carrier can be utilized.

　　

　　What modulation and demodulation technology does NB-IoT use?

　　

　　OFDMA is used for downlink, and the subcarrier spacing is 15kHz. The uplink adopts SC-FDMA, single-tone: 3.75kHz/15kHz, and multi-tone: 15kHz. Only need to support half duplex, with a separate synchronization signal. The terminal supports the indication of Single-tone and Multi-tone capabilities. The MAC/RLC/PDCP/RRC layer processing is based on the existing LTE processes and protocols, and the physical layer is optimized.

　　

　　What are the number of connected users and active users of NB-IoT base station?

　　

　　NB-IoT has 50-100 times the uplink capacity improvement compared with 2G/3G/4G, and NB-IoT can provide 50-100 times the access number compared with the existing wireless technology under the same base station. Under the frequency of 200KHz, according to the simulation test data, a single base station cell can support 50,000 NB-IoT terminals to access.

　　

　　What is the coverage of NB-IoT base station?

　　

　　NB-IoT has a gain of 20dB higher than that of LTE and GPRS base stations, and it is expected to cover underground garages, basements, underground pipelines and other places where signals are difficult to reach. According to the simulation test data, in the independent deployment mode, the coverage capacity of NB-IoT can reach 164dB, and the in-band deployment and guard band deployment need to be simulated and tested.

　　

　　What is the uplink and downlink transmission rate of NB-IoT?

　　

　　NB-IoT RF bandwidth is 200kHz. Downlink rate: greater than 160kbps and less than 250kbps. Uplink rate: greater than 160kbps and less than 250 kbps (multi-tone)/200 kbps (single-tone).

　　

　　Does NB-IoT support retransmission mechanism?

　　

　　NB-IoT adopts retransmission (up to 200 times) and low-order modulation to enhance coverage.

　　

　　Does NB-IoT support voice?

　　

　　NB-IoT supports Push to Talk without coverage enhancement. In the scenario of enhanced coverage of 20dB, only similar voicemails can be supported. NB-IoT does not support VoLTE, which requires too high delay, and the high-level protocol stack needs QoS guarantee, which will increase the cost.

　　

　　Why does the chip of NB-IoT consume low power?

　　

　　The energy consumed by a device is related to the amount or rate of data, and the size of data packets sent per unit time determines the size of power consumption. NB-IoT introduces eDRX power saving technology and PSM power saving mode, which further reduces power consumption and prolongs battery life. NB-IoT can keep devices online all the time, but it can save power by reducing unnecessary signaling and not accepting paging information when in PSM state.

　　

　　In PSM mode, the terminal is still registered in the network, but the signaling is unreachable, which makes the terminal stay in deep sleep for a longer time to save electricity. EDRX power saving technology further prolongs the sleep period of the terminal in idle mode, reduces unnecessary startup of the receiving unit, and greatly improves the downlink accessibility compared with PSM.

　　

　　Does NB-IoT sleep wake-up mode affect battery life?

　　

　　At present, the working time given by NB-IoT is based on simulation data, without considering the battery itself and environmental factors, such as self-discharge and aging of the battery, high and low temperature environmental impact, etc. In actual use, it is necessary to comprehensively evaluate the power supply time of the battery according to the actual situation. NB-IoT adopts the power-saving scheme of sleep wake-up. When the battery is awakened during sleep, it will receive instantaneous strong current, which will greatly affect the battery life. The application of meter reading usually adopts lithium thionyl chloride (Li/SOCl2) battery and super capacitor. Consumer electronics and others should be powered by li-polymer.

　　

　　Why are NB-IoT chips cheap?

　　

　　Low speed, low power consumption and low bandwidth bring low cost advantages. Low speed: it means that no large cache is needed, so the cache can be small and the DSP configuration is low; Low power consumption: it means that RF design requirements are low, and small PA can be realized; Low bandwidth: It means that there is no need for complicated equalization algorithm … These factors make the NB-IoT chip small, so the cost will be reduced.

　　

　　Taking a certain chip as an example, NB-IoT chip integrates BB, AP, Flash and battery management, and reserves the function of sensor set. The AP includes three ARM-M0 cores, and each M0 core is responsible for the application, security and communication functions respectively, which facilitates the function management and reduces the cost and power consumption.

　　

　　What is the range of NB-IoT to the device movement rate?

　　

　　NB-IoT is suitable for application scenarios with weak mobility support (such as intelligent meter reading, intelligent parking, etc.), while simplifying the complexity of the terminal and reducing the power consumption of the terminal. NB-IoT does not support mobility management in connected state, including related measurement, measurement report, handover, etc.

　　

　　What is the network delay of NB-IoT?

　　

　　NB-IoT allows a delay of about 10s, but it can support a lower delay, such as about 6s, in the environment of maximum coupling loss.

　　

　　3. Deployment of NB-IoT technology in various vertical application fields of the Internet of Things.

　　

　　What is the deployment cost of NB-IoT vertical application?

　　

　　The deployment cost of NB-IoT vertical application field includes hardware cost, network cost, installation cost and service cost. If we want to realize the scale of application field, we must reduce the deployment cost.

　　

　　What is the focus of NB-IoT in vertical application field?

　　

　　NB-IoT technology can meet the requirements of low-rate services with low power consumption, long standby, deep coverage and large capacity, and is more suitable for static services, low sensitivity to time delay, discontinuous movement and real-time data transmission. 1. Autonomous anomaly reporting business types: such as smoke alarm detectors, abnormal equipment operation, etc. The uplink data volume is extremely small (on the order of ten bytes), and the cycle is mostly in years and months. 2. Business types of autonomous periodic reporting: such as remote meter reading of public utilities and environmental monitoring, etc. The uplink data volume is small (on the order of 100 bytes), and the cycle is mostly in days and hours. 3. Service type of remote control instruction:

　　

　　For example, if the equipment is turned on/off remotely, and the equipment triggers to send an uplink report, the downlink data amount is very small (on the order of ten bytes), and the cycle is mostly in days and hours. 4. Software remote update service type: such as software patch/update, and the uplink and downlink need a large amount of data (kilobyte level), and the cycle is mostly in days and hours.

　　Application process of RTK radio network modewith RF Module For example, if it continues to develop, it will definitely become the benchmark of the industry and play an important role in leading the market. https://www.hkulike.com/

　　

　　1, instrument erection

　　

　　Complete the hardware erection and configuration of the reference station and mobile station, and build the hardware environment for the operation.

　　

　　2. New projects

　　

　　Create engineering, configure basic information such as parameters and coordinates, and complete the data foundation needed for the operation.

　　

　　3. Find the conversion parameters

　　

　　Match the plane coordinates required by the project with the default latitude and longitude coordinates, and directly obtain the required target reference frame coordinates in the operation. /4, single point correction

　　

　　Input the known plane coordinates of the measuring point and correct the parameter differences between different coordinate systems. (It can be skipped after parameter calculation, but it needs to be corrected every time the base station restarts.)

　　

　　4. Check the known points

　　

　　Measure at known points to confirm whether the parameter transformation between different coordinate systems is accurate and effective.

　　

　　5, measurement and lofting

　　

　　Carry out survey or lofting operations in the operation area to obtain the target results.

　　

　　6. Data export

　　

　　Export data from the notebook and copy it to the computer for office processing.

　　

　　Use process of RTK radio mode

　　

　　1, the erection of reference stations

　　

　　Load the battery and turn it on.

　　

　　Open the project star in the notebook and connect to the host through the Bluetooth Manager.

　　

　　Use “Host Settings” to set the host as “base station” and the host data link as “radio station”, set the corresponding radio channel, select the appropriate data format (such as RTCM32) in “Reference Station Settings”, and click “Start the base station” after obtaining the coordinates of the base station.

　　

　　When the data light flashes every second, it indicates that the reference station has been started successfully.

　　

　　2. Set up the mobile station

　　

　　Similar to the reference station, the host is set as “mobile station” and the host data link is set as “radio station”, and the radio channel corresponding to the reference station is set.

　　

　　When the data light of the mobile station flashes every second and reaches a fixed solution, it indicates that the mobile station is working normally.

　　

　　3. Parameter setting

　　

　　New Project: After the solution status is fixed, click “Project” and “New Project” and enter the project name.

　　

　　Antenna Height Setting: Click “Configuration” and “Engineering Settings” and enter the correct antenna height.

　　

　　Coordinate System Settings: Click Configure, Coordinate System Settings and Add, and enter the name of the parameter system (set at will). Select the ellipsoid name as required, and enter the actual local central meridian, and use the default values for other parameters.

　　

　　4. Find the conversion parameters

　　

　　Click “Measure” and “Point Measure” to collect the coordinate information of two known points A1 and A2 in turn.

　　

　　Click “Input”, “Calculation of Conversion Parameters” and “Add”, input the known plane coordinates of point A1, “OK” and “Select a point from the coordinate management library”, select the newly measured point A1, then complete the entry of point A2 in the same way, click “Save”, enter a user-defined file name, and click “Apply” after checking that the horizontal and elevation accuracy are correct, and then assign the parameter values to the current project.

　　

　　After the conversion is completed, the information of the third known point A3 is collected for verification.

　　

　　5, single point correction

　　

　　Every time the reference station is restarted, the mobile station should make a single point correction.

　　

　　Click “Input”, “Calibration Wizard” and “Reference Station Erected at Unknown Point” to erect the mobile station at a known control point. Enter the known plane coordinates and pole height of the mobile station, click “Calibration” and “OK” after the bubble is centered, and the calibration work is completed. After the calibration is completed, it should be checked at another known control point.

　　

　　6. Measure

　　

　　After completing the above steps, point measurement and lofting can be carried out.

　　

　　Application process of RTK radio network mode

　　

　　1, the erection of reference stations

　　

　　Insert the SIM card, load the battery, and start the machine.

　　

　　Open the project star in the notebook and connect to the host through the Bluetooth Manager.

　　

　　Use “Host Settings” to set the host as “base station” and the host data link as “network”.

　　

　　Set the network mode. Customize “Host Settings”, “Network Settings”, “Add” and “Name”, select EAGLE for “Mode”, GPGGA/CDMA for “Connection”, fill in cmnet for “APN”, enter the IP address and corresponding port, set the user name and password, and generally set the access point as the base station host body number to facilitate identification and prevent duplication. Click “OK” after setting.

　　

　　Select an appropriate data format (such as RTCM32) in “Reference Station Settings”, click “Start Base Station” after obtaining the coordinates of the base station, and when the data light flashes every second, it indicates that the reference station has been started successfully.

　　

　　2. Set up the mobile station

　　

　　In a way similar to the base station, set the host as a mobile station and the data link of the host as a network. According to the setting of the base station, select “NTRIP-UDS” as the Mode, enter the corresponding IP address, port, user name, password and access point, and click “OK” and “Connect” until the GPGGA data is successfully uploaded.

　　

　　When the data light of the mobile station flashes every second and reaches a fixed solution, it indicates that the mobile station is working normally.

　　

　　3. Parameter setting

　　

　　New Project: After the solution status is fixed, click “Project” and “New Project” and enter the project name.

　　

　　Antenna Height Setting: Click “Configuration” and “Engineering Settings” and enter the correct antenna height.

　　

　　Coordinate System Settings: Click Configure, Coordinate System Settings and Add, and enter the name of the parameter system (set at will). Select the ellipsoid name as required, and enter the actual local central meridian, and use the default values for other parameters.

　　

　　4. Find the conversion parameters

　　

　　Click “Measure” and “Point Measure” to collect the coordinate information of two known points A1 and A2 in turn.

　　

　　Click “Input”, “Calculation of Conversion Parameters” and “Add”, input the known plane coordinates of point A1, “OK” and “Select a point from the coordinate management library”, select the newly measured point A1, then complete the entry of point A2 in the same way, click “Save”, enter a user-defined file name, and click “Apply” after checking that the horizontal and elevation accuracy are correct, and then assign the parameter values to the current project.

　　

　　After the conversion is completed, the information of the third known point A3 is collected for verification.

　　

　　5, single point correction

　　

　　Every time the reference station is restarted, the mobile station should make a single point correction.

　　

　　Click “Input”, “Calibration Wizard” and “Reference Station Erected at Unknown Point” to erect the mobile station at a known control point. Enter the known plane coordinates and pole height of the mobile station, click “Calibration” and “OK” after the bubble is centered, and the calibration work is completed. After the calibration is completed, it should be checked at another known control point.

　　

　　6. Measure

　　

　　After completing the above steps, RTK radio station can carry out point measurement and lofting.

　　1. Wireless networkingIn order to open the market, radio Module Constantly improve the ability of business development and create an extraordinary brand image for it. https://www.hkulike.com/

　　

　　Networking requirements: networking in a wireless way in a local area network to realize resource sharing among devices.

　　

　　Networking mode: wireless access points are placed in the center of local area network, and wireless network cards are installed on internet devices.

　　

　　2. Mesh connection

　　

　　Wireless mesh network is a pure wireless network system, and the APS in the network can be directly connected with each other through wireless channels.

　　

　　3. Regional-oriented mobile Internet service

　　

　　Networking requirements: provide mobile Internet service for mobile devices in this area in a large range.

　　

　　Networking mode: base stations are selected in the area, and wireless access points are placed at each base station to form multiple overlapping cells to cover the area to be networked. If the wireless ad hoc network module is installed on the mobile device, you can enjoy the mobile networking service within this range.

　　

　　4. Point to point connection

　　

　　 Wireless connection between single computer and computer network

　　

　　Networking requirements: realize wireless connection between remote computers and computer network center.

　　

　　Networking mode: install a wireless access point external directional antenna in the computer network center, and install a wireless network card external directional antenna on a single machine opposite to the network center.

　　

　　 Wireless connection between computer networks

　　

　　Networking requirements: realize wireless connection between remote computer network and computer network center.

　　

　　Networking mode: install a wireless access point external directional antenna in the computer network center, and install a wireless access point external directional antenna in the remote computer network opposite to the network center.

　　

　　5. Point to multipoint connection

　　

　　 Multi-point connection with different frequencies

　　

　　Networking requirements: There are three wired networks: A, B and C. A is the central network, and it is necessary to realize the wireless connection between A network and B network and C network respectively.

　　

　　Networking mode: a wireless bridge external directional antenna is installed in network A, and a wireless bridge external directional antenna is installed in network B opposite to network A; Another wireless bridge external directional antenna is installed on the A network, and another wireless bridge external directional antenna is installed on the C network, which is opposite to the second directional antenna of the A network.

　　

　　 Co-frequency multi-point connection

　　

　　Networking requirements: There are four wired networks: A, B, C and D. A is the central network, and it is necessary to realize the wireless connection between A network and B network, C network and D network respectively.

　　

　　Networking mode: A wireless bridge external omni-directional antenna is installed on the A network, and a wireless bridge external directional antenna is installed on the B network, the C network and the D network respectively, which is opposite to the A network, and the A network is connected with the B, C and D networks at the same frequency.

　　

　　6. Relay connection

　　

　　 Connection across obstacles

　　

　　Networking requirements: wireless networking should be realized between the two networks, but there are obstacles between the geographical locations of the two networks, and there is no visible path required for microwave transmission.

　　

　　Networking mode: By establishing a relay center, find a location where two networks can be seen at the same time and set up a relay point, so that the two networks can establish a connection through relay.

　　

　　 Long distance connection

　　

　　Networking requirements: wireless networking should be realized between two networks, but the distance between the two networks exceeds the maximum communication distance that can be achieved by point-to-point connection.

　　

　　Networking mode: establish a relay point between two networks, so that the two networks can establish a connection through relay.

　　

　　Wireless mesh network can form a broadband wireless communication network covering the city, provide wireless VOIP and mobile broadband multimedia communication services, and also provide metropolitan broadband wireless mobile access services for users in certain industries.