# A Novel Battery-Supplied AFE EEG Circuit Capable of Muscle Movement Artifact Suppression
## 1 Introduction
### Problem Statement and Structure of the Present Study  
The central idea of this study arises from the observation that there is currently a shortage of EEG circuits in the recent literature that can simultaneously monitor the theta, alpha, and beta brain wave frequency bands while the user is engaged in usage protocols that involve intense compound muscle movements. As an objective, this study aims to develop a mobile and cost-effective EEG circuit that can accurately acquire the brain signal during usage protocols that require the effective handling of muscle artifacts. The proposed system is powered by a battery, uses simple sub-circuits, and incorporates filters to handle muscle artifacts. The system can potentially be used for neurofeedback training and telec-controlling devices using Brain-Computer Interfaces (BCIs). For the purposes of accurate design and reproducibility of this study, a realistic electronic model of the human brain and body is created to simulate the effects of electromagnetic interference (EMI) from the external environment. The present manuscript is organized as follows:
* Section 1 (Introduction) highlights the medical importance of acquiring an EEG signal and its role in patient monitoring. It also discusses the sub-bands of frequencies into which the EEG signal is classified and introduces the challenges that noise brings to an acquired EEG signal.
* Section 2 (Related Works in EEG Circuit Design Analog Front-End Architectures) discusses design specifications for medical- and research-grade EEG circuits. The selected case studies are elaborated with respect to the comparative analysis of various architectures of EEG AFE.
* Section 3 (Materials and Methods: Novel Proposed EEG Analog Front-End Circuit System) puts forth a novel methodology for simulating and evaluating the novel EEG AFE circuitry design against practical cases using MATLAB R2023a.
* Section 4 (Simulation and Results: Comprehensive Analysis) is presented with the objective of comparing the theoretical values with the simulated values in a real-world scenario for the given circuit design, EEG-B3V3S7C1. The circuit's performance is simulated in two of the commonest EEG measurement scenarios: the 50 Hz and 60 Hz power grid environments that exist outside the shielded lab conditions.
* Section 5 (Discussion) discusses the practical implications, potential limitations, and future perspectives of the proposed EEG circuit design.
* Section 6 (Conclusions) summarizes the entire article.  
The authors, along with this work, provide an extended Supplementary Materials file with two sections \"SA\" and \"SB\" to this manuscript. Those sections contain information that is important mostly for a reader who is a novice to the field and needs more context and clarification in order to follow the flow of ideas in the main text. See Supplementary Materials \"SA\" for more details:  
* for each wave and its implications at Table SA1.
* for each noise source and their corresponding frequency ranges at Table SA2.
* of the various components involved in EEG circuits, along with their respective functions at Table SA3.
* of the various technical distinctions in design specifications between medical-grade and research-grade EEG circuits at Table SA4.