Performance of OFDMA resource scheduling in joint mobile radio and radar networks

In this paper, we study the impact of time-frequency resource scheduling on the performance of an orthogonal frequency-division multiplexing (OFDM)-based radar receiver for joint mobile radio and radar networks. Our results illustrate how the sparse distribution of resources in the time-frequency grid, as used for orthogonal frequency-division multiple access (OFDMA), affects the cost function of a maximum-likelihood estimator. Based on our results, we provide a simple set of rules for the design of resource scheduling schemes in joint networks. Furthermore, we reveal that radar sensing with OFDM can benefit from multiple algorithms and procedures already employed in mobile communication standards, such as synchronization and error correction.

I. Introduction

Recently the research interest in joint wireless communication and radar sensing is starting to grow, mainly motivated by the dual-use of spectral resources. A comprehensive survey of the topic with various approaches is presented in [1], which also outlines the possibility to perform radar sensing and communication with a joint waveform. One such concept is described in [2], in which the communication and radar systems are displaced in such a way that the radar system also receives the communications transmissions. Another concept, called cooperative passive coherent location (CPCL), is presented in [3], which builds on the idea to reuse transmissions of wireless communication systems to perform simultaneous communication and radar sensing at the receivers. The radar sensing is performed using the same waveform and even the same spectral resources that are simultaneously utilized for communication. This way, both domains would cooperate on the usage of spectral resources, effectively creating a joint mobile radio and radar network, in which the mobile radio is the enabler for radar sensing, information sharing, and medium access control. As the radar sensing is performed by the communication receivers, transmitters and receivers are not co-located and the sensing becomes similar to passive radar. While most of the publications in the area of joint wireless communication and radar sensing focus on full-duplex monostatic radar sensing setups, recent publications have also demonstrated feasibility in passive bistatic setups [4], [5].