# Shielding Grounding Optimization Method for Spaceborne Multi-Cable
## 1 Introduction  
The limited space inside a spacecraft payload, the complex connection relationships between the electronics systems, the large number of cables, and the different sizes and frequencies of the signals transmitted by each cable make the cable signals and related signals vulnerable to interference. Remote sensing is being developed to enable immediate and early prediction [1]. The surface anomaly signals are often weak [2] and are more easily obscured by interference between cables, making the system unable to achieve effective detection; a significant reduction in the impact of signal interference between load cables has become the focus of remote sensing developmental research [3]. To reduce interference, the cable is usually wrapped in a metal shield. The grounding method employed for the shield greatly influences the shielding effect; a shield with an inappropriate grounding method will not exhibit effective shielding and may even increase  
inner shielding, the induced current of the cable was reduced to about 5% [6]. [PERSON]'s research showed that a poor shield grounding state could reduce the shielding performance by more than 30 dB [7]. Therefore, choosing the best cable shield grounding state is important for improving the shielding effect, reducing the interference received by the cable, and increasing the electromagnetic compatibility of aerospace electronics systems. However, the current studies on cable shielding and grounding have the following limitations. Firstly, most of the existing studies on shielding effects under different shielding grounding conditions have focused on instances where the number of cables is small, and there is usually only one cable that is subjected to interference and one interfering cable [8; 9]. The research on interference between multiple cables is often limited to theoretical calculations and modeling simulations, lacking experimental verification [10; 11]. Secondly, the existing studies usually derive and solve the transfer impedance or shielding efficiency of the cable shield using an electromagnetic field analytical formula, which is complicated [12; 13]. In practice, it is difficult to accurately describe the coupling relationship between so many cables using electromagnetic field analysis. Although some researchers [14] have simply analyzed the mechanism by which the shield protects against an electromagnetic field by using the parasitic inductance and parasitic capacitance from the topological structure of the circuit, and also proposed measures to suppress interference, they are limited to a single cable, and the circuit topology of the coupling relationship between multiple cables becomes very difficult to describe. Thirdly, standard test methods, such as the injection method [15] and triaxial test method, are generally used for experimental verification in existing studies [16; 17], which makes it difficult to build cost-effective experimental platforms. Moreover, these standard testing methods explore the transfer impedance of a single shield; therefore, it is difficult to measure the shielding efficiency when multiple cables interact. In addition, the number of grounding states of the cable shield exponentially increases with the number of cables, and it is very time-consuming to test all the grounding states one by one. In summary, there is no method for determining the optimal grounding state for multiple cable shielding. In this study, the shield grounding optimization of a spaceborne multi-cable was studied. The paper is organized as follows. The Section 1 is the Introduction. The Section 2 introduces the overall process of the grounding optimization method for a spaceborne multi-cable shield and explains each step of the method, respectively. Additionally, this work is compared with related work to illustrate the advantages and disadvantages of the proposed methods.