Precoder and Decoder Co-Designs for Radar and Communication Spectrum Sharing

Abstract

The coexistence of radar and communication systems is necessary to facilitate new wireless systems and services due to the shortage of the useful radio spectrum. Moreover, changes in spectrum regulation will be introduced in which the spectrum is allocated in larger chunks and different radio systems need to share the spectrum. For example, 5G NR, LTE and Wi-Fi systems have to share the spectrum with S-band radars. Managing interference is a key task in coexistence scenarios. Cognitive radio and radar technologies facilitate using the spectrum in a flexible manner and sharing channel awareness between the two subsystems. In this paper, we propose a nullspace-based joint precoder–decoder design for coexisting multicarrier radar and multiuser multicarrier communication systems. The maximizing signal interference noise ratio (max-SINR) criterion and interference alignment (IA) constraints are employed in finding the precoder and decoder. By taking advantage of IA theory, a maximum degree of freedom upper bound for the K+1-radar-communication-user interference channel can be achieved. Our simulation studies demonstrate that interference can be practically fully canceled in both communication and radar systems. This leads to improved detection performance in radar and a higher rate in communication subsystems. A significant performance gain over a nullspace-based precoder-only design is also obtained.

Evaluating RF Hardware Characteristics for Automotive JCRS Systems Based on PMCW-CDMA at 77GHz

“…Moreover, studies to expand the current model to a multiuser system are ongoing. In this context, precoder-coder design to maximize the signal interference noise ratio like Cui et al [82], power allocation like in [83] are also discussed. Besides, we extend the analysis of hardware impairments, the same as Adler et al [49] proposed.…”

QoS-Aware Precoder Optimization for Radar Sensing and Multiuser Communications Under Per-Antenna Power Constraints

“…Generally speaking, the research on ISAC has been conducted in two main directions, i.e., the coexistence of radar and communication (CRC) and dual functional radarcommunication (DFRC). CRC focuses on efficient management of the mutual interference between radar sensing and wireless communications [6], [7] and it dates back to 1960s [8]. To maximize the efficiency of coexistence, the CRC time allocation was studied in [9].…”