# Optimization Scheme for Modulation of Data Transmission Module in Endoscopic Capsule
## 1 Introduction
Previous studies have shown that DCSK can significantly improve performance in highly dynamic and noisy environments, such as those found in in-body channels. [PERSON]. [33] explored DCSK for body area networks (BANs) and demonstrated that this modulation scheme effectively mitigates the effects of fading and interference in in-body communication environments, ensuring reliable data transmission under adverse conditions. Furthermore, the challenges posed by highly dynamic channels are discussed, and a DCSK-based solution that performs well in fluctuating channel conditions is proposed, enhancing the communication quality and robustness [34]. In summary, DCSK offers several advantages for in-body communication systems, including resilience to channel impairments, low power consumption, and enhanced security features. These benefits make it a highly suitable candidate for the future of body-centric medical and healthcare networks. The contributions of this paper are shown as follows:  
(1) This paper first introduces the model of the in-body channel environment, as well as the channel environment model of WBANs, including the establishment of relevant models and the setting of parameters. Based on the characteristics of the in-body channel environment and the demand for transmission efficiency, a Multi-level Index Position M-ary Differential Chaos Shift Keying (MIP-MDCSK) scheme is designed. This scheme improves the transmission rate by combining index position with MDCSK, where part of the transmission bits are realized by index position and the other part is implemented by the MDCSK modulation itself. The principle of its implementation is discussed in detail. (2) The energy efficiency (EE), spectral efficiency (SE), and complexity of the proposed scheme are derived and calculated. A comparison with other related schemes shows that the proposed approach achieves a significant improvement in both energy efficiency and spectral efficiency, albeit with a slight increase in complexity. Specifically, the trade-off between complexity and performance is carefully examined, and it is found that by sacrificing a small amount of computational complexity, the scheme offers considerable gains in both energy and spectral efficiency. (3) Simulations were conducted to compare the performance of the proposed scheme in the in-body channel environment within WBANs. The results show that the scheme demonstrates excellent bit error rate (BER) performance in the in-body channel environment. This indicates that the proposed scheme is well-suited for in-body environments. Additionally, the varying BER performance in the environments can be used to infer information about the current channel conditions, such as the specific type of channel environment and the position of the body. This provides a potential method for adaptive communication systems to dynamically adjust to environmental changes. Section 2 introduced the channel model and presents the principle of the MIP-MDCSK scheme for impulsive noise in a channel. Section 3 computes EE, SE, and the complexity of MIP-MDCSK and compares them with corresponding schemes. Analysis of performances, simulation, and results are presented in Section 4, respectively. Section 5 concludes the paper.