Iterative Interference Cancellation for Time Reversal Division Multiple Access

Abstract

Time reversal (TR) has been proposed as a competitive precoding strategy for low-complexity devices relying on ultra-wideband waveforms, as it shifts the signal processing complexity to the transmitter side. This transmit precoding paradigm can address the need for low-power, low-complexity receivers, which is particularly important for the Internet of Things. Due to its spatio-temporal focusing property, TR has also been used to design multiple access schemes for multi-user scenarios. However, with timedivision multiple access, the signals received by users suffer from a significant level of inter-symbol interference and inter-user interference, which often requires additional processing at the receiver side. This paper proposes an iterative TR scheme that aims to reduce the level of interference, while keeping the processing complexity only at the transmitter side. The performance of this protocol is evaluated using analytical derivations. Its superiority over conventional TRDMA is demonstrated through simulations and experimental measurements.INDEX TERMS Time reversal precoder, iterative processing, multiple access, ultra-wideband, precoding.

6G: Technology Evolution in Future Wireless Networks

“…The scheme allows simultaneous transmission from a multi-transmitting antenna. A competitive precoding technique based on the time reversal phenomenon for devices with low complexity dependent on the ultra-wideband waveforms has been proposed in [161]. The scheme targets the reduction of the interference level while balancing the complexity of the processing from the transmitter side.…”