Short Frame OFDM for Sensor Networks: Time Synchronization and Channel Estimation Design

This paper focuses on the design of a low-latency and low-power OFDM communication system where devices send frames consisting of a reduced number of symbols (one OFDM symbol), with a reduced number of carriers. We study the design of the OFDM receiver blocks in terms of time synchronization and channel estimation. Furthermore, we adapt these OFDM techniques to the case of short frame transmissions in order to meet the requirements of a low-latency and low-power sensor network. Then, we analyse the performance of our solutions and we show that our design allows the system to work close to the theoretical limits. We investigate the impact of the number of pilots on time synchronization performance, and we show the advantage of adding a memory to the channel estimation block.