A Dual-Function Radar Communication System Using Index Modulation

Abstract

Dual-function radar communication (DFRC) systems implement both sensing and communication using the same hardware. Such schemes are often more efficient in terms of size, power, and cost, over using distinct radar and communication systems. Since these functionalities share resources such as spectrum, power, and antennas, DFRC methods typically entail some degradation in both radar and communication performance. In this work we propose a DFRC scheme based on the carrier agile phased array radar (CAESAR), which combines frequency and spatial agility. The proposed DFRC system, referred to as multi-carrier agile joint radar communication (MAJoRCom), exploits the inherent spatial and spectral randomness of CAESAR to convey digital messages in the form of index modulation. The resulting communication scheme naturally coexists with the radar functionality, and thus does not come at the cost of reduced radar performance. We analyze the performance of MAJoRCom, quantifying its achievable bit rate. In addition, we develop a low complexity decoder and a codebook design approach, which simplify the recovery of the communicated bits. Our numerical results demonstrate that MAJoRCom is capable of achieving a bit rate which is comparable to utilizing independent communication modules without affecting the radar performance, and that our proposed low-complexity decoder allows the receiver to reliably recover the transmitted symbols with an affordable computational burden. arXiv:1909.04223v1 [eess.SP]

Bit Constrained Communication Receivers In Joint Radar Communications Systems

“…Let A Proj :=Ã Proj ⊗ IU . The corresponding digital matrixB Proj is then obtained by substituting A Proj into (9). Finally, the dynamic range γ is set via [18, App.…”

“…We focus here on a specific radar-oriented DFRC scheme, which combines IM and FMCW waveforms. Nonetheless, the same formulation used to design the proposed HAD receiver can be applied to a broader family of joint waveforms, including MAJoRCom [9], and OFDM waveforms [11]. To design the corresponding HAD receivers, one should properly formulate the received signal model and the relationship between the observed signal and the desired output.…”

“…The common DFRC setup considers systems acting as radar transceivers which communicate with some remote receiver. Consequently, the main focus in DFRC research is on the design of the dual-function system and waveforms applicable for both sensing and information transmission [6][7][8][9][10][11][12][13][14][15][16], often resulting in wideband radaroriented signaling which require high computational resources to reliably decode at the receiver side. In various prospective DFRC use cases, such as vehicle-to-infrastructure (V2I) communications, the receiver is a hardware-limited power-constrained device, e.g., a D. Ma, T. Huang and Y. Liu are with the Department of EE, Tsinghua University, Beijing, China (e-mail: mdy16@mails.tsinghua.edu.cn; {huangtianyao, yiminliu}@tsinghua.edu.cn).…”

Theoretical Analysis of Multi-Carrier Agile Phased Array Radar

“…CAESAR also achieves performance within a relatively small gap compared to the costly WMAR, while avoiding the hardware complexity associated with the usage of instantaneous wideband components. In addition, CAESAR can also exploit its spatial agility character, which is not present in FAR or WMAR, to realize a DFRC system, as discussed in our companion paper [20].…”

“…Furthermore, the combined randomization of frequency and antenna allocation can be exploited to realize a dual-function radar communication (DFRC) system [17]- [19] by embedding digital information into the selection of these parameters. We study the application of CAESAR as a DFRC system in a companion paper [20], and focus here on the radar and its performance.…”