An Advanced GNU Radio Receiver of IEEE 802.15.4 OQPSK Physical Layer

In this article, we present an advanced coherent receiver for the IEEE 802.15.4 offset quadrature phase-shift keying (OQPSK) physical layer and provide an open-source implementation in the GNU Radio framework. Simulation and field test results show that the proposed receiver achieves about 11-dB power gain over an existing GNU Radio receiver, which treats OQPSK as minimum-shift-keying (MSK) for low-complexity processing. While suitable modules can be added to the MSK-based receiver for performance enhancement, the proposed receiver still maintains a 6-dB power gain. The proposed coherent receiver is attractive for IoT applications where a powerful software-defined-radio (SDR)-based gateway is deployed to interact with various sensors.