Channel Sounding Waveforms Design for Asynchronous Multiuser MIMO Systems

TL;DR

This paper introduces a new waveform design for asynchronous multi-user MIMO systems, deriving models, proposing a chirp waveform, and analyzing capacity, with results showing optimality and equivalence under specific conditions.

Contribution

It provides a novel asynchronous MU-MIMO channel model, a chirp waveform design meeting resolution constraints, and capacity analysis showing equivalence with synchronous systems.

Findings

Chirp waveform achieves CRB in integer time offsets.

Channel capacity regions are equivalent under certain conditions.

Simulation confirms theoretical results.

Abstract

In this paper we provide three contributions to the field of channel sounding waveform design in asynchronous Multi-user (MU) MIMO systems. The first contribution is a derivation of the asynchronous MU-MIMO model and the conditions that the sounding waveform must meet to independently resolve all of the spatial channel responses. Next we propose a chirp waveform that meets the constraints and we show that the MSE of our system meets the Cramer-Rao Bound (CRB) when the time offset is an integer multiple of the sampling interval. Finally we demonstrate that the channel capacity region of the asynchronous system and synchronous system is equivalent under certain conditions. Simulation results are provided to illustrate the findings.