Downlink and Uplink Cooperative Joint Communication and Sensing

TL;DR

This paper introduces a novel cooperative joint communication and sensing scheme that unifies downlink and uplink sensing, significantly improving estimation accuracy by leveraging channel reciprocity and fusion techniques.

Contribution

It proposes a unified MUSIC-based sensing scheme and a fusion method for downlink and uplink JCAS, enhancing sensing accuracy and target distinction.

Findings

Location and velocity estimation errors are about 20 dB lower than existing schemes.

The unified scheme accurately estimates AoA, range, and Doppler.

Simulation results validate the effectiveness of the proposed approach.

Abstract

Downlink (DL) and uplink (UL) joint communication and sensing (JCAS) technologies have been individually studied for realizing sensing using DL and UL communication signals, respectively. Since the spatial environment and JCAS channels in the consecutive DL and UL JCAS time slots are generally unchanged, DL and UL JCAS may be jointly designed to achieve better sensing performance. In this paper, we propose a novel DL and UL cooperative (DUC) JCAS scheme, including a unified multiple signal classification (MUSIC)-based JCAS sensing scheme for both DL and UL JCAS and a DUC JCAS fusion method. The unified MUSIC JCAS sensing scheme can accurately estimate AoA, range, and Doppler based on a unified MUSIC-based sensing module. The DUC JCAS fusion method can distinguish between the sensing results of the communication user and other dumb targets. Moreover, by exploiting the channel reciprocity, it can also improve the sensing and channel state information (CSI) estimation accuracy. Extensive simulation results validate the proposed DUC JCAS scheme. It is shown that the minimum location and velocity estimation mean square errors of the proposed DUC JCAS scheme are about 20 dB lower than those of the state-of-the-art separated DL and UL JCAS schemes.