## 1 Introduction  
With the exponential growth in the use of electronic equipment, spectrum resources are becoming increasingly scarce. As important frequency systems, radar and communication each occupy a large part of the spectrum resources and continue to penetrate into the traditional spectrum range of the other party. Therefore, the relationship between radar and communication systems, namely the frequency band sharing between the two, has attracted widespread attention [1]. The joint radar communication system (JRCS) is not only conducive to reducing the occupation of the spectrum and improving the utilization efficiency of spectrum resources, but also conducive to the reduction in sensor volume and the simplification of signal processing through the full cooperation between the two functions. In recent years, such joint systems have been widely used in both military and civilian applications [2, 3]. The core implementation of JRCS has two main research directions. One is to multiplex two independent signals in the time domain, frequency domain, space domain, and code domain under the premise that the two systems do not interfere with each other [4, 5, 6]. References [7, 8, 9, 10, 11, 12, 13] cover the latest waveform multiplexing technology and scheme in recent years. In contrast, another research direction is to use a single spectrum shared transmission signal for simultaneous radar detection and data communication, that is, dual-functional radar communication (DFRC) [14]. Generally, in the former, it is difficult to eliminate mutual interference between signals, so the joint system cannot significantly improve spectral efficiency. The difficulty of the latter research lies in balancing the performance indicators of radar and communication systems so that the resolution of radar is increased and the communication performance metrics such as bit error rate (BER) are also improved. At present, the development of beyond 5G (B5G) communication systems is in full swing. However, at B5G frequencies, orthogonal frequency division multiplexing (OFDM) is challenged by several effects, pushing alternative modulation formats [15]. As a candidate waveform for 5G communication, the filter bank multicarrier (FBMC) waveform is shaped by a well-designed prototype filter [16] to make the sidelobe of the frequency domain subcarrier extremely low, thereby reducing the inter-carrier interference (ICI), relaxing the requirements of inter-carrier synchronization, and ensuring its better performance in synthetic aperture radar (SAR) and communication integrated channels [17]. At the same time, FBMC does not use the cyclic prefix (CP) to combat inter-symbol interference (ISI) and ICI, improving spectral efficiency and avoiding false target imaging. In modern national defense development, to achieve self-security and ensure that own weapons work well, combat equipment usually uses multiple electronic countermeasures (ECMs), including stand-off supported jamming (SSJ) and self-defense jamming (SDJ). Various types of ECM jamming have been developed, classified as either suppressive or deceptive jamming [18; 19]. Multi-false-target jamming is commonly used to generate deceptive jamming. The ECM system senses incoming radar signals and simulates the target echo to generate replicas capable of confusing radar, hindering the identification of true and false targets [20; 21]. Joint communication and jamming guarantees the unity of the joint system, namely complete communication with friendly own targets while jamming enemy radar or communication equipment. The joint system's main challenge is designing a common waveform that improves the system's communication performance while maintaining its jamming capabilities or increases the jamming performance of the system while maintaining its communication capability. However, few studies have explored the technology of joint communication jamming.