Joint Radar and Communication: A Survey

Joint radar and communication(JRC)technology has become important for civil and military applications for decades.This paper introduces the concepts,characteristics and advantages of JRC technology,presenting the typical applications that have benefited from JRC technology currently and in the future.This paper explores the state-of-the-art of JRC in the levels of coexistence,cooperation,co-design and collaboration.Compared to previous surveys,this paper reviews the entire trends that drive the development of radar sensing and wireless communication using JRC.Specifically,we explore an open research issue on radar and communication operating with mutual benefits based on collaboration,which represents the fourth stage of JRC evolution.This paper provides useful perspectives for future researches of JRC technology.

Dual-Use Signal Design for Radar and Communication via Joint Orthogonal Signal and Phase Modulation

This paper proposes a new information modulation resorting to orthogonal signal and its phase for dual-function radar communication(DFRC)systems.Focusing on the standardized linear frequency modulation(LFM)signal by additional phase,a bank of signals enjoying satisfactory autocorrelation and cross-correlation characteristics,are generated.Then,these signals map the different information as well as their phases are also modulated to increase the communication bit rate,thus yielding a series of dual-use signals.Finally,the radar detection and communication performance of dual-use signals are also provided through numerical simulation and half-physical platform verification,confirming the effectiveness of the designed signals compared with the existing design strategy.

A Brief Introduction on Joint Radar and Communication Systems

Joint radar and communication(JRC)technology is gradually becoming an essential approach to alleviating spectral congestion.Radar and communications systems were designed with common spectral and hardware resources to reduce size,improve performance,reduce cost,and decongest the spectrum.Various approaches have been proposed to achieve the coexistence of radar and communication systems.This paper mainly focuses on the research directions of radar communication coexistence(RCC)and dual-function radar communication systems(DFRC)in JRC technology.We summarize and analyze the existing research problems in the JRC era.According to the characteristics and advantages of JRC technology,we highlight several potentials in military and commercial applications.

Joint Modulations of Electromagnetic Waves and Digital Signals on a Single Metasurface Platform to Reach Programmable Wireless Communications

In current wireless communication and electronic systems,digital signals and electromagnetic(EM)radiation are processed by different modules.Here,we propose a mechanism to fuse the modulation of digital signals and the manipulation of EM radiation on a single programmable metasurface(PM).The PM consists of massive subwavelength-scale digital coding elements.A set of digital states of all elements forms simultaneous digital information roles for modulation and the wave-control sequence code of the PM.By designing digital coding sequences in the spatial and temporal domains,the digital information and farfield patterns of the PM can be programmed simultaneously and instantly in desired ways.For the experimental demonstration of the mechanism,we present a programmable wireless communication system.The same system can realize transmissions of digital information in single-channel modes with beamsteerable capability and multichannel modes with multiple independent information.The measured results show the excellent performance of the programmable system.This work provides excellent prospects for applications in fifth-or sixth-generation wireless communications and modern intelligent platforms for unmanned aircrafts and vehicles.

基于FBMC信号的低截获雷达通信一体化波形设计

针对正交频分复用(OFDM)雷达通信一体化波形方案中循环前缀引起的弱回波掩盖问题和敌方战场低截获概率问题,该文提出了基于滤波器组的多载波偏移正交幅度调制(FBMC-OQAM)的低截获雷达通信一体化波形设计方案。分别构建FBMC雷达通信一体化波形与目标检测概率、通信信道容量之间的数学模型,在保证一定系统雷达与通信性能的条件约束下,设计最小化系统总发射功率联合优化问题,优化各个子载波发射功率分配方案。该算法利用测量值和信道状态信息,对下一个脉冲的发射波形参数进行优化设计,实现自适应传输。此外,从平均模糊函数角度分析了FBMC作为雷达信号的可行性和优势。仿真结果表明,与等功率分配方案相比,该文提出的功率分配方案可有效降低一体化系统总发射功率,从而实现低截获性能,并且FBMC波形可有效降低循环前缀引起的距离旁瓣,提高雷达分辨率与信息速率。

一种基于OFDM-chirp的雷达通信一体化波形设计与处理方法

雷达通信一体化波形设计是近年来的研究热点。有学者提出利用正交频分复用(OFDM)信号的奇偶载波分别调制雷达与通信功能来实现一体化。但OFDM通信系统一般采用循环前缀(CP)来避免多径效应带来的载波间干扰(ICI)和符号间干扰(ISI),这会降低能量利用率,并会形成虚假目标,影响雷达性能;此外,传统的OFDM一体化信号对多普勒比较敏感,微小的多普勒频偏也会带来正交性能的严重下降。该文在此基础上提出了一种新的波形设计和处理方法。该方法利用空白保护间隔替代循环前缀,可以在对抗多径效应的同时避免出现由于循环前缀引入的虚假目标,有效防止载波间干扰和符号间干扰。在信号处理方法上,该文提出利用雷达发射信号的先验信息进行信道估计与补偿多普勒频偏的方法。与传统方法相比,该文方法降低了系统在导频与训练序列等资源上的开销,提升了能量利用率和频谱效率,并且改善了峰值旁瓣比(PSLR)、积分旁瓣比(ISLR)和通信误码率(BER)等指标。仿真实验验证了该文方法的有效性。