Software-Defined Radio-Based IEEE 802.15.4 SUN OFDM Evaluation Platform for Highly Mobile Environments

Next-generation Internet of Things (IoT) systems require faster data transmission, support for moving objects, and long-distance transmission when compared to the currently available IoT systems. The IEEE 802.15.4 smart utility network (SUN) orthogonal frequency-division multiplexing (OFDM) can satisfy these requirements. Mobile-communication-oriented receiver systems are typically used in urban environments for SUN OFDM. However, the evaluation depends on computer simulations and requires an experimental evaluation platform based on software-defined radio (SDR) that can modify transmitter-receiver functions. We present a platform for SUN OFDM that enables high-speed mobile communication. The proposed platform comprises a signal generator-based transmitter and an SDR-based receiver; the receiver baseband signal processing is performed by MATLAB. We also proposed signal processing functions that can receive the SUN OFDM packets even at speeds of tens of km/h. We applied a simplified universal time-domain windowed (UTW)-OFDM scheme to this platform to operate even at sub-1 GHz, where the spectrum mask is more limited. In the experimental evaluation, the required packet error rate for SUN OFDM was achieved in an 80 km/h multipath fading environment, and out-of-band emission can be suppressed by over 43 dB from the peak power while achieving performance equivalent to that without applying the simplified UTW.