The Impact of Using Digital Filter and Analog Filter on Surface Electromyography Signal

Many accident cases result in humans having to going a surgery to save them, then performing muscle therapy to help the patient’s recovery after going through the post-surgery. The purpose of this therapy is the patient’s body to its normal state. Exoskeleton is an additonal clothing-like tool that aims to both protect and increase the wearer's abilities. Meanwhile electromyography (EMG) is a technique to evaluate and record the electrical activity produced by skeletal muscles. The purpose of this study was to analyze the differences in using of analog and digital filters on EMG, as well as the effect on the exoskeleton simulation. The method used in the main design consists of the myoware module, notch circuit, low pass filter, arduino uno, DAC module, teraterm software, and matlab. The intercepted signal was taken from the biceps using a disposable electrode (AG/AGCL.). The EMG signal tapped by the myoware module then is continued to another circuit, then was recorded on the Teraterm software, and analyzed in MATLAB. The voltage value on the analog filter is 1.541 Volt during relaxation and 2.086 Volt during contraction, while the digital filter that has passed through the DAC has a value of 41.8 mVolt during relaxation and 269.1 mVolt during contraction. The results of this study obtained that digital and analog filter values ​​have an average difference of 5 to 30. The conclusion of this research is that the tool can detect changes in the use of analog and digital filters. Therefore, in the future research, development can be made to compare other types of digital filters along with replacement to wireless systems. The benefit or purpose of this research is as a simulation of exoskeleton skeletal motion and to see the difference between the use of digital and analog filters.

Implementation of an Inductorless 5th Order Band-Pass Filter

This paper demonstrates the design and implementation of an inductorless analog band-pass filter (BPF). Band-pass filters are widely used in communication systems, wireless transceivers and audio systems, they only pass signals within a desired frequency range. The principles mentioned in this article can be generalized to design any analog filter regardless of its order, approximation and prototype. The design procedure can be broken down into three main parts, first of all, a passive low-pass filter (LPF) is implemented, then the passive LPF is converted into a passive BPF. Finally, the passive BPF is transformed into an active BPF by adding operational amplifiers. The active BPF is then modified into two different topologies, the first in which the inductors are replaced with simulated- inductors (gyrators), while in the second topology, less operational amplifiers are used. <br>

Implementation of an Inductorless 5th Order Band-Pass Filter

This paper demonstrates the design and implementation of an inductorless analog band-pass filter (BPF). Band-pass filters are widely used in communication systems, wireless transceivers and audio systems, they only pass signals within a desired frequency range. The principles mentioned in this article can be generalized to design any analog filter regardless of its order, approximation and prototype. The design procedure can be broken down into three main parts, first of all, a passive low-pass filter (LPF) is implemented, then the passive LPF is converted into a passive BPF. Finally, the passive BPF is transformed into an active BPF by adding operational amplifiers. The active BPF is then modified into two different topologies, the first in which the inductors are replaced with simulated- inductors (gyrators), while in the second topology, less operational amplifiers are used. <br>

Control-Bounded Analog-to-Digital Conversion

A control-bounded analog-to-digital converter consists of a linear analog system that is subject to digital control, and a digital filter that estimates the analog input signal from the digital control signals. Such converters have many commonalities with delta–sigma converters, but they can use more general analog filters. The paper describes the operating principle, gives a transfer function analysis, and describes the digital filtering. In addition, the paper discusses two examples of such architectures. The first example is a cascade structure reminiscent of, but simpler than, a high-order MASH converter. The second example combines two attractive properties that have so far been considered incompatible. Its nominal conversion noise (assuming ideal components) essentially equals that of the first example. However, its analog filter is a fully connected network to which the input signal is fed in parallel, which potentially makes it more robust against nonidealities.

A 28 nm CMOS 100 MHz 67 dB-Dynamic-Range 968 µW Flipped-Source-Follower Analog Filter

This paper presents a fourth-order continuous-time analog filter based on the cascade of two flipped-source-follower (FSF) biquadratic (biquad) cells. The FSF biquad adopts two interacting loops (the first due to the classic source-follower, and the second to the additional gain path) which lower the impedances of all circuit nodes with relevant benefits in terms of noise power reduction and linearity enhancement. The presented device was integrated in 28 nm CMOS and featured 100 MHz −3 dB bandwidth with 67 dB Dynamic-Range. Input IP3 was 12 dBm at 10 and 11 MHz input tone frequencies. Total power consumption was 0.968 mW (0.484 mW per cell). Hence, the filter performed one of the highest figures-of-merit (160.7 dBJ-1) compared with analog state-of-the-art filters.

Analog Filters Design for Improving Precision in Proton Sound Detectors

This paper analyzes how to improve the precision of ionoacoustic proton range verification by optimizing the analog signal processing stages with particular emphasis on analog filters. The ionoacoustic technique allows one to spatially detect the proton beam penetration depth/range in a water absorber, with interesting possible applications in real-time beam monitoring during hadron therapy treatments. The state of the art uses nonoptimized detectors that have low signal quality and thus require a higher total dose, which is not compatible with clinical applications. For these reasons, a comprehensive analysis of acoustic signal bandwidth, signal-to-noise-ratio and noise power/bandwidth will be presented. The correlation between these signal-quality parameters with maximum achievable proton range measurement precision will be discussed. In particular, the use of an optimized analog filter allows one to decrease the dose required to achieve a given precision by as much as 98.4% compared to a nonoptimized filter approach.