Noise Cancellation Technique Research Articles

Digital Noise-Cancellation Circuit Implementation Using Proposed Algorithm and Karnaugh Map in a MASH 2-1 Delta-Sigma Modulator

This paper presents the implementation of two digital noise-cancellation circuits (DNCCs) using a proposed algorithm and a Karnaugh map for a [Formula: see text] multistage noise-shaping (MASH) delta-sigma modulator (DSM). The MASH architecture inherits a superior signal-to-noise-and-distortion ratio (SNDR) with the aid of an efficient noise-cancellation technique either in the analogue or digital domain. The key motivation of this study was to design an area-efficient DNCC. The first approach employed a proposed algorithm (Algorithm-based DNCC) to implement the DNCC and to construct a delay block with an inverter and transmission gate. The second approach involved a Karnaugh map (K-map DNCC) and a delay block with a pair of D flip-flops. A maximum simulated signal-to-noise ratio of 135[Formula: see text]dB was completed with optimal analogue scaling coefficients for the proposed [Formula: see text] MASH DSM with DNCC. The simulated SNDRs of the Algorithm-based DNCC and K-map DNCC were 91.04[Formula: see text]dB and 91.16[Formula: see text]dB, respectively. Measured results show that the SNDR of the Algorithm-based DNCC, the SNDR of the K-map DNCC, power consumption and core area are approximately 58.7[Formula: see text]dB, 62.1[Formula: see text]dB, 0.26[Formula: see text][Formula: see text]W and 2275[Formula: see text][Formula: see text]m2, respectively, for the designed DNCCs with an operating frequency of 10.24[Formula: see text]MHz and supply voltage of 1.8[Formula: see text]V. The transistor counts of the Algorithm-based DNCC are 74 transistors, while they are 106 transistors for the K-map DNCC. The proposed Algorithm-based DNCC saves 32 transistors and approximately reduces its chip area to 69.8% of the K-map DNCC.

Foetus Heartbeat Extraction

Fetal Electrocardiogram Extraction from Mother's Womb is the subject of this report, which includes a thorough examination and implementation. The Fetal ECG is made up of various thoracic and abdominal ECG signals from a pregnant lady. For estimating corrupted signals due to additive noise or interference, the Adaptive Noise Cancellation Technique is used. These algorithms are used to update the weights of an adaptive filter in the Adaptive Noise Cancellation system: The algorithms Least Mean Square, Normalized Least Mean Square, and Leaky Least Mean Square are utilized. This method can be used in both single-input, single-output (SISO), and multiple-input, single-output (MISO) systems (MISO). When compared to the LMS and LLMS algorithms, the NLMS algorithm performs better in both systems.

Enhancing Doubly Fed Induction Generator Low-Voltage Ride-through Capability Using Dynamic Voltage Restorer with Adaptive Noise Cancellation Technique

Some of the major challenges facing micro-grids (MGs) during their connection with the utility grid are maintaining power system stability and reliability. One term that is frequently discussed in literature is the low-voltage ride-through (LVRT) capability, as it is required by the utility grid to maintain its proper operation and system stability. Furthermore, due to their inherent advantages, doubly fed induction generators (DFIGs) have been widely installed on many wind farms. However, grid voltage dips and distortion have a negative impact on the operation of the DFIG. A dynamic voltage restorer (DVR) is a commonly used device that can enhance the LVRT capability of DFIG compared to shunt capacitors and static synchronous compensator (STATCOM). DVR implements a series compensation during fault conditions by injecting the proper voltage at the point of common coupling (PCC) in order to preserve stable terminal voltage. In this paper, we propose a DVR control method based on the adaptive noise cancelation (ANC) technique to compensate for both voltage variation and harmonic mitigation at DFIG terminals. Additionally, we propose an online control of the DC side voltage of the DVR using pulse width modulation (PWM) rectifier to reduce both the size of the storage element and the solid-state switches of the DVR, aiming to reduce its overall cost. A thorough analysis of the operation and response of the proposed DVR is performed using MATLAB/SIMULINK under different operating conditions of the grid. The simulation results verify the superiority and robustness of the proposed technique to enhance the LVRT capability of the DFIG during system transients and faults.

A Wideband Low-Power RF-to-BB Current-Reuse Receiver Using an Active Inductor and 1 /f Noise-Cancellation for L-Band Applications

A low-power and wideband RF-to-baseband (BB) current-reuse receiver (CRR) front-end utilizing both a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1/f$ </tex-math></inline-formula> noise cancellation (NC) technique and an active inductor (AI) is proposed tuned to operate from 1 GHz to 1.7 GHz for L-Band applications, including those that require high modulation bandwidths. The CRR front-end employs a single supply and shares the bias current of the low noise transconductance amplifier (LNTA) with the BB circuits to reduce the power consumption. To minimize the losses of the radio frequency (RF) signal right before down-conversion, a high impedance AI circuit isolates the mixer input from the CRR output node. The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1/f$ </tex-math></inline-formula> NC circuit suppresses the low frequency noise of the LNTA that leaks to the output. A common-gate LNTA with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mathrm {g_{m}}$ </tex-math></inline-formula> -boosting, along with a single-to-differential LC-balun are used to enhance the input matching, conversion gain and noise figure (NF). The proposed receiver is fabricated in a TSMC 130 nm CMOS process and occupies an active area of 0.54mm2. The input matching (S11) is below −10 dB from 1 GHz to 1.7 GHz. At a local-oscilator (LO) frequency of 1.3 GHz, intermediate-frequency (IF) of 10 MHz and default current settings, the CRR achieves a conversion gain of 41.5 dB, a double-sideband (DSB) NF of 6.5 dB, and an IIP3 of −28.2 dBm while consuming 1.66 mA from a 1.2 V supply.

A Novel Technique of Noise Cancellation based on Stationary Bionic Wavelet Transform and WATV: Application for ECG Denoising

In this paper, is proposed a novel technique of Electrocardiogram (ECG) denoising. It is based on the application of Wavelet/Total-Variation (WATV) denoising approach in the domain of the Stationary Bionic Wavelet Transform (SBWT). It consists firstly in applying the SBWT to the noisy ECG signal for obtaining two noisy coefficients namedwtb1 and wtb2 which are respectively details and approximation coefficients. For estimating the level of noise altering the signal, namedσ, we use wtb1. This noise is an additive Gaussian white noise. The thresholding ofwtb1 is secondly performed employing the soft thresholding and a denoised coefficient wtd1 is obtained. This thresholding requires the use of a certain threshold, thr which is computed using σ. Thedenoising ofwtb2 is performed using WATV denoising method and we obtain a denoised coefficient, wtd2. This WATV denoising method also uses σ. The denoised ECG signal is finally obtained by applying the inverse of SBWT (SBWT-1) to wtd1 and wtd2. The proposed technique performance is justified by the results obtained from the computations of Signal to Noise Ratio (SNR), Minimum Square Error (MSE), Mean Absolute Error (MAE), Peak-SNR (PSNR) and Cross-Correlation (CC).

A Fractional-N Digital MDLL With Background Two-Point DTC Calibration

This article presents a fractional- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$N$ </tex-math></inline-formula> digital multiplying delay-locked loop (MDLL) that employs a digital-to-time converter (DTC) to control the reference injection for the fractional- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$N$ </tex-math></inline-formula> operation. The presented MDLL features a background two-point DTC calibration that simultaneously corrects the DTC gain and offset errors to achieve a low-jitter and low-spur architecture. The DTC errors are sensed using an embedded time-to-digital converter (TDC) and extracted in the digital domain for reduced implementation overhead. A new TDC dithering and dither noise cancellation technique is used to improve the estimation accuracy of the DTC errors at the presence of TDC quantization error and differential nonlinearity (DNL). In addition, the adaptive dither noise cancellation scheme uses a comb filter to decouple the dither noise and DTC error estimations, allowing the two schemes to operate simultaneously. The proof-of-concept MDLL prototype fabricated in 65-nm CMOS achieves −60-dBc fractional spur and 1.67-ps rms jitter at around 20-MHz offset. With the proposed calibration scheme, a >25-dB spur reduction in reference and fractional spurs is demonstrated.

A Wideband Noise and Harmonic Distortion Canceling Low-Noise Amplifier for High-Frequency Ultrasound Transducers.

This paper presents a wideband low-noise amplifier (LNA) front-end with noise and distortion cancellation for high-frequency ultrasound transducers. The LNA employs a resistive shunt-feedback structure with a feedforward noise-canceling technique to accomplish both wideband impedance matching and low noise performance. A complementary CMOS topology was also developed to cancel out the second-order harmonic distortion and enhance the amplifier linearity. A high-frequency ultrasound (HFUS) and photoacoustic (PA) imaging front-end, including the proposed LNA and a variable gain amplifier (VGA), was designed and fabricated in a 180 nm CMOS process. At 80 MHz, the front-end achieves an input-referred noise density of 1.36 nV/sqrt (Hz), an input return loss (S11) of better than −16 dB, a voltage gain of 37 dB, and a total harmonic distortion (THD) of −55 dBc while dissipating a power of 37 mW, leading to a noise efficiency factor (NEF) of 2.66.

A 13.8-ENOB Fully Dynamic Third-Order Noise-Shaping SAR ADC in a Single-Amplifier EF-CIFF Structure With Hardware-Reusing kT/C Noise Cancellation

To design noise-shaping successive approximation register (NS-SAR) analog-to-digital converters (ADCs) with high resolution and good power efficiency, two key bottlenecks need to be addressed. One is to realize a high-order loop filter with low circuit overhead, and the other is to mitigate the thermal noise. This article presents an NS-SAR ADC that synergistically addresses both challenges. To achieve high-order efficiency, it proposes an innovative error feedback-cascaded integrator feedforward (EF-CIFF) structure that realizes third-order noise shaping using only a single amplifier. It combines the merits of both structures, showing improved robustness, and is free of dc offset concern. On reducing the kT/C noise, this work features a sampling kT/C noise cancellation (SNC) technique that reuses the native hardware of the EF-CIFF structure. An open-loop self-quenching floating-inverter dynamic amplifier (FIDA) is used to support all amplification with low noise and power. Prototyped in 65-nm CMOS, this work achieves 84.8-dB signal-to-noise-distortion ratio (SNDR) with 625-kHz bandwidth (BW) (OSR = 8) and 119 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{W}$ </tex-math></inline-formula> , leading to 182-dB Schreier Figure of Merit (FoM). It uses only 0.8-pF input capacitance, which is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$5\times $ </tex-math></inline-formula> smaller than prior NS-SAR ADCs with similar oversampling ratio (OSR) and SNDR.

Frequency-Locked Loops in Electrical Power and Energy Systems: Equivalent or Different to Phase-Locked Loops?

In the electrical power and energy (EPE) area, the traditional concept in designing the synchronization system of power converters is using the phase-locked loop (PLL) concept. An alternative way is using the frequency-locked loop (FLL) concept, which is also known as the adaptive notch filter, adaptive noise cancelation technique, gradient descent estimator, adaptive observer, D-estimation method, and transformation angle detector, among others names. Along with the increased popularity and application of FLLs in EPE systems, the misconception about this design concept is growing. To be more exact, most EPE research communities introduce FLLs as synchronization systems of different properties compared to PLLs. This article aims to explain the main reasons behind this misconception and contribute to dispelling it.

Sensing and Cancellation Circuits for Mitigating EMI-Related Common Mode Noise in High-Speed PAM-4 Transmitter

The common mode (CM) current in differential circuits generates CM noise which radiates in the environment and causes electromagnetic interference (EMI) with electronic devices in proximity. This noise is generated due to imbalance in the charging and discharging paths of the driver circuit and asymmetric equalization. A systematic study of how asymmetric equalizer increase the CM noise is still lacking. Few active on-chip solutions are proposed for wireline transmitters up to 20-Gbps speed. However, these solution does not suppress CM noise by the equalizer and they could not support four-level pulse amplitude modulation (PAM-4) optical transmitters. This paper analyzes two potential sources of EMI-related CM noise, the common mode logic (CML) driver and feed forward equalization (FFE) circuit, and presents a novel on-chip active circuit technique for automatic CM noise cancellation in high-speed PAM-4 transmitter. This solution provides the benefits of small size and low cost by eliminating the need for discrete components to suppress EMI. The post-layout simulation demonstrates that the CM noise cancellation circuit (CMNC) efficiently mitigate the EMI by suppressing the CM noise up to 90% and consumes 5 mW, with core area of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$17 \mu m \times 9 \mu m$ </tex-math></inline-formula> .

A Scalable Readout IC Based on Wideband Noise Cancelling for Full-Rate Scanning of High-Density Microelectrode Arrays.

This paper presents a highly scalable readout IC for high-density microelectrode arrays (MEAs). Although the recent development of large-scale high-density MEAs provides opportunities to achieve sub-cellular neural recording over a wide network area, it is challenging to implement the readout IC that can operate with such MEAs. The requirement of high-speed recording in large-scale arrays induces wideband-noise folding, which makes it challenging to achieve a good noise performance for high-fidelity neural recording. Moreover, for the wideband readout, the major noise contributor changes from the readout circuit to the cell-electrode interface. In this paper, we first show why the interface noise becomes the dominant noise source and elucidate its component that contributes the most: sealing resistance. Then, we propose a new readout circuit structure, which can effectively cancel the wideband interface noise. As a result, the signal-to-noise ratio of input neural spike signals is improved dramatically in all cell-attachment or sealing conditions. Particularly, it is shown that under weakly sealed conditions, the spikes can be detected only when the proposed wideband noise cancellation technique is applied.

A Wideband Sub-㎓ Receiver Front-end Supporting High Sensitivity and Selectivity Mode

A low noise and highly linear wideband RF front-end circuit for sub-㎓ Internet of Things (IoT) applications is proposed. The proposed frontend is composed of a broadband single-ended LNA, a wideband differential LNA employing thermal noise cancellation technique, and an in-phase and quadrature (I/Q) linearized harmonic rejection mixer (HRM). Depending on the interference environment, the proposed front-end supports two operation modes having high sensitivity and selectivity performance by enabling or disabling the first building block of the single-ended LNA. At high sensitivity mode, the frontend shows a voltage gain (A<SUB>v</SUB>) of greater than 38 ㏈, a noise figure (NF) of less than 2.1 ㏈, an input-referred third-order intercept point (IIP3) of greater than -23 ㏈m, and an input-referred second-order intercept point (IIP2) of greater than +15 ㏈m in the sub-㎓ frequency band. Concerning for high selectivity mode, it achieves an Av of greater than 22.5 ㏈, a NF of less than 4.7 ㏈, an IIP3 of greater than – 6.8 ㏈m, and an IIP2 of greater than +50 ㏈m over the same operating frequency range.

High-Precision Time-Frequency Signal Simultaneous Transfer System via a WDM-Based Fiber Link

In this paper, we demonstrate a wavelength division multiplexing (WDM)-based system for simultaneously delivering ultra-stable optical frequency reference, 10 GHz microwave frequency reference, and a one pulse per second (1 PPS) time signal via a 50 km fiber network. For each signal, a unique noise cancellation technique is used to maintain their precision. After being compensated, the transfer frequency instability in terms of the overlapping Allan deviation (OADEV) for the optical frequency achieves 2 × 10−17/s and scales down to 2 × 10−20/10,000 s, which for the 10 GHz microwave reference, approaches 4 × 10−15/s and decreases to 1.4 × 10−17/10,000 s, and the time uncertainty of the 1 PPS time signal along the system is 2.08 ps. In this scheme, specific channels of WDM are, respectively, occupied for different signals to avoid the possible crosstalk interference effect between the transmitted reference signals. To estimate the performance of the above scheme, which is also demonstrated in this 50 km link independent of these signals, the results are similar to that in the case of simultaneous delivery. This work shows that the WDM-based system is a promising method for building a nationwide time and frequency fiber transfer system with a communication optical network.

Adaptive Phase Noise Cancellation Technique for Fiber-Optic Interferometric Sensors

The optical source phase noise is one of the main factors influencing the noise performance of fiber-optic interferometric measurement systems. The phase noise is directly proportional to the optical path length difference of the interferometer and wavelength instability of the optical source. Conventional phase noise suppression techniques involve the use of highly stable optical sources and reduction of path length differences of sensing interferometers. However, such methods are not always appropriate for all interferometric configurations. Alternative phase noise suppression techniques suggest the use of an auxiliary reference interferometer for independent measurements of the phase noise. In this case, the phase noise signal can be directly subtracted from the sensor signal. But equal path length differences are required for all interferometers in the measurement system. In this paper, an adaptive phase noise cancellation technique for fiber-optic interferometric sensors is presented. The proposed technique is based on the real-time evaluation of optical path length differences for all interferometers in the measurement system. This approach doesn't require identical path length differences and takes into account their variations caused by environmental conditions. Thus, the optical source phase noise can be independently measured by the reference interferometer and subtracted from the sensor signal with the required attenuation. The results of experimental investigations of the proposed technique for two types of interferometric schemes are presented. It is shown that the proposed technique demonstrates the phase noise reduction up to 30 dB in the frequency range up to 500 Hz.

Low Power Inductorless LNA using Noise Cancellation Technique for UWB Applications

This paper deals with the performance analysis of low power (LP) Low noise amplifier (LNA) for Ultra wide band (UWB) applications. The proposed inductorless LNA has two stages, one is complementary common gate (CCG) stage and the other one is body biased common source stage (BBCS). In CCG stage current reused techniques is used to reduce the power consumption and to provide broad band impedance matching in UWB band. Apart from this, CCG stage is also used to reduce the noise of BBCS stage using noise cancellation technique. BBCS stage is used to provide high and flat gain. Biasing voltage is optimized through body voltage. The proposed LNA was successfully simulated in 45-nm CMOS technology. All the simulations have been done for a range of frequency 3GHz to 8GHz in cadence virtuoso. The proposed LNA achieved a peak power gain (S21) of 17.1dB and −16.4dB S11, at frequency 4.1GHz. The bandwidth of proposed LNA is 3.7GHz −5.5 GHz, −9.9dBm IIP3with minimum NF is 1.1dB. The proposed LNA consumes a power of 3.6mW with supply voltage 1V.

A 0.061-mm² 1–11-GHz Noise-Canceling Low-Noise Amplifier Employing Active Feedforward With Simultaneous Current and Noise Reduction

This article proposes a novel wideband common-gate (CG) common-source (CS) low-noise amplifier (LNA) with active feedforward for simultaneous current and noise reduction. By employing an active feedforward stage in the main path, the current dissipation and the thermal noise are effectively suppressed, while the noise and distortion cancelation properties of CG-CS topology are preserved. Moreover, no extra noise is introduced since the additional g <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> -boost amplifier follows the same noise-canceling (NC) principle as the CG amplifier, and its noise can be fully canceled at the output theoretically. Thus, the proposed LNA benefits from the g <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> -boosting and NC technique simultaneously to obtain a good tradeoff between gain, noise figure (NF), and power consumption. Fabricated in standard 40-nm CMOS technology, the measured results show the proposed LNA exhibits a peak gain of 17 dB, NF of 3.5-5.5 dB from 1 to 11 GHz and an IIP3 of -2.8 dBm at 6 GHz. It consumes 9 mW from a 1.2-V supply and occupies a very compact die area of 0.061 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .

Auxiliary Feed-Forward Noise Cancellation Techniques for a Generic Type-II Ring Oscillator Phase Locked Loop

This brief presents an auxiliary feed-forward noise cancellation (AFFNC) technique that can be applied to a generic Type-II ring oscillator (RO) PLL. The AFFNC technique uses a stand alone sub-sampling phase detector (SSPD) embedded into an alignment loop to extract and cancel noise from the RO output. Along with AFFNC, which uses one reference edge for noise extraction, a Double Sampled AFFNC (DS-AFFNC) which utilizes both the rising and falling edge of the reference for noise extraction is also presented. By using both the reference edges, higher cancellation bandwidth is achieved in DS-AFFNC. The phase-domain model developed for AFFNC and DS-AFFNC show a 2.9x and 3.9x integrated jitter reduction respectively.

Music Source Separation Using ASPP Based on Coupled U-Net Model

Noise has established itself as one of the factors that interfere with modern human life, and various noise canceling techniques have been studied to prevent noise. While the old era's noise-canceling technique focused on the physical soundproofing technique, multiple studies have been conducted on the active noise canceling technique that removes only the activated noise in the current era. Active noise canceling (ANC) or digital noise-canceling technology is based on the sound source separation method. This leads to sound source separation technology, which refers to the technology to separate individual sound signals from mixture sounds. Most of the source separation technologies focus on improving speech, not noise reduction. This technology makes it possible to obtain desired sound information more accurately and further improves noise-canceling technology by eliminating unwanted sound information. To provide deeper capability and more enhanced sound separation than the existing structure, we are focused on coupled U-Net model and Atrous spatial pyramid pooling technique (ASPP). This paper presents the music source separation method that combined Coupled U-Net structure with Atrous spatial pyramid pooling technique. To prove the proposed source separation method, we compared GNSDR, GSIR, and GSAR using MIR-1K, a data set that can evaluate the performance of the music source separation. Performance results show that the proposed source separation method overcame other methods' disadvantages and strengthened the feature map.

A 4.8-dB NF, 440-μW Bluetooth Receiver Front-End With a Cascode Noise Canceling LNTA

An ultralow power (ULP) low-noise receiver front-end for the BLE application is presented in this letter. The tradeoff between noise and power consumption is mitigated by employing a transformer-based passive $g_{m}$ -boosting common-gate low noise transconductance amplifier (LNTA). Local-positive feedback (LPF) and feedforward (FF) noise cancellation techniques are combined in the LNTA to further lower noise. After the passive mixer, a TIA implements complex filtering with a moderate conversion gain. The receiver front-end, fabricated in TSMC 28-nm process, consumes only $440~\mu \text{W}$ under 0.9-V supply with a minimum noise figure of 4.8 dB.

Detection and Characterization of Physical Activity and Psychological Stress from Wristband Data

Wearable devices continuously measure multiple physiological variables to inform users of health and behavior indicators. The computed health indicators must rely on informative signals obtained by processing the raw physiological variables with powerful noise- and artifacts-filtering algorithms. In this study, we aimed to elucidate the effects of signal processing techniques on the accuracy of detecting and discriminating physical activity (PA) and acute psychological stress (APS) using physiological measurements (blood volume pulse, heart rate, skin temperature, galvanic skin response, and accelerometer) collected from a wristband. Data from 207 experiments involving 24 subjects were used to develop signal processing, feature extraction, and machine learning (ML) algorithms that can detect and discriminate PA and APS when they occur individually or concurrently, classify different types of PA and APS, and estimate energy expenditure (EE). Training data were used to generate feature variables from the physiological variables and develop ML models (naïve Bayes, decision tree, k-nearest neighbor, linear discriminant, ensemble learning, and support vector machine). Results from an independent labeled testing data set demonstrate that PA was detected and classified with an accuracy of 99.3%, and APS was detected and classified with an accuracy of 92.7%, whereas the simultaneous occurrences of both PA and APS were detected and classified with an accuracy of 89.9% (relative to actual class labels), and EE was estimated with a low mean absolute error of 0.02 metabolic equivalent of task (MET).The data filtering and adaptive noise cancellation techniques used to mitigate the effects of noise and artifacts on the classification results increased the detection and discrimination accuracy by 0.7% and 3.0% for PA and APS, respectively, and by 18% for EE estimation. The results demonstrate the physiological measurements from wristband devices are susceptible to noise and artifacts, and elucidate the effects of signal processing and feature extraction on the accuracy of detection, classification, and estimation of PA and APS.