Low power baseband processor for IoT terminals with long range wireless communications

In this paper, we propose a new baseband architecture for Internet of Things (IoT) terminals that support long range communications such as those based on Orthogonal Frequency-Division Multiple Access (OFDMA) and spread spectrum technologies. We analyze the workload profiles of both systems and find that the frame detection unit has by far the highest computational load. Based on this analysis, we propose a simple architecture that uses only a scalar datapath. To optimize for low power consumption, we introduce application specific instructions that minimize register accesses and include address generation units for streamlined memory access. Preliminary synthesis results in 65nm node show that this architecture has an area of 0.204 μm2 and average energy consumption of 2.41 nJ/cycle when operated at 3MHz with supply voltage of 1.08 V.