PMC: Parallel multi-protocol communication to heterogeneous IoT radios within a single WiFi channel

The exponentially increasing number of Internet of things (IoT) devices introduces spectrum crisis to the widely used industrial, scientific, and medical (ISM) frequency band. Since IoT devices use heterogeneous radios with different bandwidths (e.g., 20 MHz for WiFi and 2 MHz for ZigBee), traditional interference avoidance methods, such as time-division multiple access (TDMA) and carrier-sense multiple access (CSMA), have very low spectrum utilization. This is because TDMA and CSMA allocate the packets at time domain, without considering the bandwidth difference of different IoT radios. To address this issue, we propose PMC, a novel communication system that enables parallel multi-protocol communication to heterogeneous IoT radios (i.e., WiFi and ZigBee) within a single WiFi channel. Our extensive evaluations show that PMC achieves the throughput of up to 121.02 kbit/s and 319.76 Mbit/s for parallel communication to ZigBee and WiFi, respectively. Compared with TDMA and CSMA, the spectrum utilization of PMC is increased by 2.3 and 1.8 times, respectively.