Wireless communication technology-LPWA communication technology
LPWAN (Low Power Wide Area Network):
Low-power wide-area network, designed for IoT applications with low bandwidth, low power consumption, long distance, and large number of connections. Just as the short-range wireless network includes WIFI, Bluetooth, ZigBee and other technologies. LPWA also contains multiple technologies, such as LoRa, Sigfox, Weightles and NB-IoT. Since it is a "wide area" network, it will inevitably involve network operations. Therefore, the LPWA network is generally deployed by a telecommunications operator or a specialized IoT operator. Since the basic connection of the LPWA network is basically "things", it is usually also called a "private network for the Internet of Things".
Features of LPWA:
① "Long-distance communication"
② "Low-rate data transmission"
③ "Low power consumption"
From the characteristics of LPWAN, we can find that if the Internet of Things is targeted for long-distance transmission, the amount of communication data is small, and battery-powered long-term operation is required. Devices can use this protocol. Most IoT applications usually only need to transmit a small amount of data. For example, sensors in enterprise workshops only generate data when devices are abnormal. These devices generally consume very little power and can work for a long time with battery power.
Therefore, LPWA is most suitable for two types of Internet of Things applications:
one is a fixed-location, relatively dense-density scenario, such as a smart water meter in a building, storage management, or other equipment data collection system. Although cellular networks have been used in these areas, The signal penetration problem has always been its shortcomings;
another type , long-distance, battery-powered applications, such as smart parking, asset tracking and geological hydrology monitoring, etc., cellular networks can be applied, but can not solve the problem of high power consumption.
①LPWA-SigFox :
Sigfox deploys a low-power wide area network (LPWA) globally to provide Internet of Things (IoT) connection services. User equipment integrates RF modules or chips that support the Sigfox protocol. After the connection service is activated, you can connect to the Sigfox network.
- The user equipment sends a Sigfox protocol data packet with application information. The nearby Sigfox base station is responsible for receiving and transmitting the data packet back to the Sigfox cloud server. The Sigfox cloud then distributes the data packet to the corresponding client server, which is analyzed and processed by the client server. Application information to realize wireless connection from client device to server.
- The SigFox network utilizes ultra-narrowband UNB technology, the transmission power consumption level is very low, and it can still maintain a stable data connection. The SigFox wireless link uses the unlicensed ISM radio frequency band. The frequency differs according to national regulations. 868MHz is widely used in Europe and 915MHz in the United States.
SigFox network technology uses ultra-narrow band modulation technology. A single base station can achieve the transmission of network messages up to 1,000 kilometers, and each base station allows up to 1 million Internet of Things (IoT) device terminals.
Attract IoT connectivity through free frequency bands, low-power devices and simplified network architecture.
② LPWA-LoRa:
LoRa is the abbreviation of "Long Range", maintained and managed by the LoRa Alliance, and is a technology that implements network data communication based on the physical layer. It supports two-way data transmission and conforms to a series of open source standards. The specific solution for its network implementation is called LoRaWAN, which was developed by Semtech and supported by IBM. Lora can be applied to automatic meter reading, smart home and building automation, wireless early warning and security systems, industrial monitoring and control, and remote irrigation systems.
LoRa uses unlicensed spectrum to support services. LoRa is an ultra-long-distance wireless transmission scheme based on spread spectrum technology. This changes the previous compromise between transmission distance and power consumption, providing users with a simple system that can achieve long distance, long battery life, and large capacity, and then expand the sensor network. At present, LoRa mainly operates in the global free frequency band.
③LPWA-NB-IoT:
NB-IoT is a narrow-band Internet of Things based on cellular, which is built on a cellular network and consumes only about 180KHz of bandwidth. It can be directly deployed on GSM network, UMTS network or LTE network to reduce deployment cost and achieve smooth upgrade.
NB-IoT focuses on the low-power and wide-coverage Internet of Things market, and is an emerging technology that can be widely used worldwide. It has the characteristics of wide coverage, multiple connections, low speed, low cost, low power consumption and excellent architecture.
At the same time, according to the R14 version of 3GPP, NB-IoT can support base station positioning, and can support mobility scenarios within 80 km / h. The advantages of NB-IoT, such as low power consumption, wide coverage, low cost, and large capacity, can be widely used in a variety of vertical industries, such as remote meter reading, asset tracking, smart parking, and smart agriculture.
④LPWA-eMTC:
eMTC is the wireless Internet of Things solution proposed by Ericsson. eMTC has designed the soft characteristics of the wireless IoT network based on LTE access technology, mainly for low-speed, deep coverage, low power consumption, large-connected IoT application scenarios.
Compared with NB-IoT, the eMTC rate is higher, up to 1Mbps, but the coverage is smaller, the power consumption is larger, and the capacity is also smaller. In addition, eMTC provides certain voice communication capabilities.
⑤LPWA-eLTE-IoT
Huawei eLTE-IoT solution is a narrowband wireless IoT solution based on the 3GPP standard specially developed for the industry IoT market. eLTE-IoT is based on the unlicensed ISM spectrum below 1GHz, uses flexible and easy-to-deploy lightweight devices, and supports standard IoT protocols to connect with the enterprise's existing application platform. Meter reading, smart parking, industrial sensor monitoring and other services provide network support.
