Analysis of SX1280 chip lora module's ability to resist WIFI strong interference electromagnetic environment
The LoRa module of the SX1280 chip has great advantages in intersecting with traditional modulation methods in the case of WIFI interference. The use of the LoRa physical layer provides us with some potential additional performance benefits compared to traditional modulation techniques for coexistence and provides additional immunity to in-band and in-channel interference. The specific advantages of the lora module are as follows: 1. Spread spectrum: LoRa is a spread spectrum modulation technology. A coding gain can be obtained through spread spectrum modulation, because the signal can be received with a negative signal-to-noise ratio. At the same time, in the absence of interference, this is equivalent to reception in noise, and in the presence of co-channel interference, this is equivalent to the ability to receive the desired signal power which is weaker than the interfering signal. 2. Low bandwidth: Reducing bandwidth has two benefits. First, the lower bandwidth reduces the influence of adjacent signals, making it less likely to fall victim to interference. If we compare the bandwidth of a LoRa signal to a wider band Wi-Fi signal, we see that even a wide LoRa signal occupies only a small fraction of a Wi-Fi channel. This brings us to a second benefit. The power of the Wi-Fi signal is distributed over the entire Wi-Fi channel. Therefore, the energy seen in the narrower part of this channel will be a fraction of this energy. Simply put, even in the case of co-channel interference, we are only exposed to a fraction of the signal power means we receive a fraction of the Wi-Fi signal power. 3. Forward Error Correction and Interleaving Technology: Another advantage of the LoRa modem is the availability of FEC (Forward Error Correction) and interleaving technology. Forward error correction allows redundancy to be introduced into the message, allowing modification and restoration of damaged finite bits. Even FEC sequential bit errors (i.e. adjacent corrupted bits) are the most difficult to correct. For this reason, the interleaving technique is employed. It's a technique of reallocating information in a packet so that after reconstruction, errors are less likely to come from adjacent bits. 4. Partial symbol loss immunity: In addition to all the previously mentioned benefits of the LoRa physical layer, it is also worth noting that we can lose up to half of a LoRa symbol before losing the data within the symbol. In the case of interference immunity, this gives us enormous immunity to interference (over 100 dB in some cases). High-power pulsed interferometers can be tolerated if they occupy less than 50% of the LORA symbol duration. It is worth mentioning that the E28-2G4M12S wireless module launched by Chengdu Ebyte Electronic Technology Co., Ltd., this lora module is a wireless module developed based on Semtech's SX1280 chip. The LoRa module has 2.4G spread spectrum communication (equivalent to 2.4G of SX1278 G version), the communication distance is better than that of the Zigbee module, and the power consumption is about 1/4 of the power consumption of the Zigbee module. The maximum power is 12.5dBm. The lora module comes with an impedance-matched PCB antenna, and the transmission distance can reach 3 kilometers. It has excellent performance and is worth choosing. E28-2G4M12S is a 2.4GHz RF transceiver module designed and produced by Ebyte, with long communication distance: it has extremely low current consumption in low power consumption mode. This module is a small-volume patch type (pin spacing 1. 27mm), and the module comes with a high-performance PCB onboard antenna and IPEX interface. This series adopts 52MHz industrial-grade high-precision low-temperature drift active product vibration: to ensure its industrial characteristics and its stable performance. Using Semtech's SX1280 radio frequency chip, this chip contains a variety of physical layers and a variety of modulation methods, such as LoRa, FLRC, GFSK. The special modulation and processing methods greatly increase the transmission distance of LoRa and FLRC modulation: it is a high-performance IoT wireless transceiver, and compatible with Bluetooth protocol. Excellent low power consumption performance, on-chip DC-DC and Time-of-flight make this chip powerful and can be used in smart home, security system, location tracking, wireless ranging, wearable devices, smart bracelets and health management, etc. . The SX1280 chip supports RSSI, and users can realize in-depth secondary development according to their needs: The SX1280 chip also integrates time of flight, which is suitable for ranging functions.