Abstract:
Orthogonal Time Frequency Space (OTFS) is a two-dimensional modulation technique designed in the delay-Doppler (DD) domain. Each symbol experiences a sparse channel with ...Show MoreMetadata
Abstract:
Orthogonal Time Frequency Space (OTFS) is a two-dimensional modulation technique designed in the delay-Doppler (DD) domain. Each symbol experiences a sparse channel with low variability in the DD domain rather than the time-varying multi-path channel in conventional orthogonal frequency division multiplexing systems. In practical applications, fractional Doppler shifts is unavoidable due to the limited frame duration. Channel dispersion caused by fractional Doppler shifts makes the channel estimation more difficult and causes data aliasing. In this paper, we propose an adaptive scheme to reduce fractional Doppler shifts. Doppler shift compensation is performed on time-domain signals and the number of time-domain symbols is changed to approximate the quantized Doppler shifts integers. With the proposed adaptive scheme, the overhead of the reference signal can be significantly reduced with the fractional Doppler shifts eliminated. Simulation results show that block error rate performance is not degraded and system throughput is improved with the proposed scheme.
Date of Conference: 26-29 March 2023
Date Added to IEEE Xplore: 12 May 2023
ISBN Information: