The SX127x platform incorporates LoRa (long range) spread spectrum technology in addition to the traditional GFSK modulation. Spread spectrum technology has been used in other applications for a number of years but has not been available until today as a low-cost solution suitable for sensor networks.
Using the LoRa technology, the SX127x family achieves a range of more than 15 km in a suburban environment and 2 km to 5 km in a dense urban environment while operating under US, EU, Chinese and Japanese regulatory limits. Most deployed systems for metering, security or industrial automation are limited in range to 1-2 km in a suburban environment. The additional range provided by LoRa eliminates the need for repeaters in these applications, significantly simplifying the system design and lowering the total cost of deployment.
The SX1276 covers all the major sub-GHz frequency bands while the SX1277 is a cost-optimised version targeted at applications that support data rates from 5 kbps to 40 kbps such as security systems. The SX1278 is optimised for the rapidly growing smart meter market in China using the 470-510MHz band.
All devices deliver over 100 dB of blocking immunity to out-of-band interfering signals, which is a 15 dB advantage over competing devices. Additionally, the SX127x family has a 25 dB improvement over FSK devices for rejecting in-band interfering signals. This makes the device especially effective in industrial, scientific and medical (ISM)-band applications such as security and metering because it provides immunity from sub-GHz frequency 4G/LTE signals. This immunity, combined with the SX127xX’s highly linear RF front-end, makes it the most reliable and robust solution for operating in the presence of strong interfering signals.