## 1 Introduction  
As promising candidates for Beyond 5G (B5G) and 6G communication systems [1], LEO satellites, which can be applied in communications, remote sensing, navigation, and other fields [2, 3], have attracted extensive attention in military and civilian fields due to their wide communication coverage and long transmission distances. With the explosive growth of wireless services, future wireless communication systems are expected to provide higher capacity and transmission rates. LEO satellite systems have been proposed to provide broadband access in unserved areas, especially in scenarios where ground network deployment is economically impractical [4, 5, 6]. However, some criminals have exploited the excellent characteristics of LEO satellites to engage in illegal activities, such as unauthorized broadcasting of events in large stadiums or illegal disclosure of information in military restricted areas. Unauthorized ships often generate extensive jamming to overwhelm satellite signals. These actions result in significant economic losses and pose serious security threats [7]. Therefore, preventing unauthorized actions and the illegal use of LEO satellites has become a crucial issue in the field of communication security. In terms of electronic countermeasures, existing jamming techniques mainly consist of blanket jamming and deception jamming [8; 9]. Blanket jamming is relatively easy to implement but may affect the communication ability of one's own equipment, which is not an issue with deception jamming [10; 11]. Deception jamming is mainly divided into repeater deception jamming and generative deception jamming [12; 13; 14]. Generative deception jamming primarily targets signals with known formats [15], the operational environment needed for which is lacking in LEO satellite communication. Repeater deception jamming involves adding time delays to various satellite signals before forwarding them. However, achieving precise synchronization is challenging in LEO satellite communication due to the fast movement of satellites [16]. Therefore, optimizing communication jamming for LEO satellites has become an important research direction. Existing jamming optimization methods mainly focus on a single domain. However, due to the frequent network switching in LEO satellite networks, single-domain jamming optimization methods cannot meet the needs of LEO satellite communication jamming. Therefore, finding a real-time multi-domain communication jamming optimization method with a high success rate is urgently needed in the field of LEO satellite countermeasures. To address these issues, this study extensively studies the composition of LEO satellite communication systems and the time-frequency characteristics of communication signals. Combining the channel model of a LEO satellite and the spatial parameters of jammers, a LEO satellite downlink distributed jamming optimization method using a non-dominated sorting genetic algorithm is proposed. The main innovations of this study are as follows:  
1. This study proposes a distributed jamming cooperative control model. Distributed jammers determine the specific orientation of visible satellites through intercepting LEO satellite signals, exchange information with surrounding distributed jammers, continuously update and adjust their positions in real time, and achieve continuous switching for different LEO satellites with high speeds. 2. This study utilizes the third-generation non-dominated sorting genetic algorithm for multi-objective optimization, optimizing jamming signals in the power, time, and frequency domains to maintain solution set diversity; improve optimization efficiency; avoid the algorithm falling into local optima; and jam the downlink of LEO satellites. 3. This study constructs a jamming experimental comparison platform and implements it as hardware.