rf-star rf-al42uh module is a wireless serial port pass-through module developed based on asr6501 chip(uart), using the standard lora wan protocol, supports the development of standard gateway communication. 3.3v ttl level output. workfrequency of 433 mhz. compared with traditional rf technology, lora spread spectrum technology has concentrated power density and strong anti-interference abilitythe characteristics of high density and longer transmission distance. to meet the needs of battery power supply, suitable for ultra-low power networking applications.