Power Harvesting Efficiency Research Articles

Deep adversarial learning models for distribution patterns of piezoelectric plate energy harvesting

This paper presents a novel approach utilizing piezoelectric plate structures with random electrode distribution patterns for energy harvesting applications across various vibration modes. For the first time, leveraging electromechanical Finite Element Analysis (eFEA) and data extraction techniques, we investigate the integration of conditional Generative Adversarial Networks (cGAN)-based dynamic models for this purpose. The cGAN offers an effective technique for generating realistic synthetic data conditioned on input parameters, thereby enabling the creation of diverse and representative datasets for training energy harvesting systems. The integration of eFEA with cGAN opens up new possibilities for optimizing the design and performance of piezoelectric energy harvesters across various applications. Specifically, we explore four distinct cGAN models-based mechanics of energy harvesters by deploying distribution patterns. These models include training data generated by stacking simultaneously mode images, utilizing separate cGAN models for each mode, labeling images by mode, and concatenating all mode images into one. Our study focuses on assessing the effectiveness of these models in minimizing loss in cGAN-based power generation and predicting Structural Similarity Index Measure (SSIM) values, and more importantly, identifying the predicted data point outputs from the generated pixel image extractions. By analyzing the generated data from numerical model and its application in deep learning, we aim to enhance the understanding of the effects of distribution patterns and image processing techniques for optimal power generation and the effectiveness of piezoelectric energy harvesting systems across different vibration modes. The studies explore how different distribution patterns affect the power harvesting efficiency and frequency bandwidth, utilizing the generated datasets.

Global MPPT controllers for enhancing dynamic performance of photovoltaic systems under partial shading condition

This research focuses on the development and evaluation of global maximum power point tracking MPPT controllers for enhancing the dynamic performance of Photovoltaic (PV) systems under partial shading conditions. Three different controllers, namely Proportional-Integral (PI), Fractional-Order PI (FOPI), and Fuzzy Logic Controllers (FLC), are studied in conjunction with a modified Incremental Conductance (IC) and Fractional Open-Circuit Voltage (FOCV) algorithms. The proposed controllers with a novel optimization algorithm called Atom Search Optimization Algorithm (ASOA) are compared with classical control. The objective is to investigate the effectiveness of the global MPPT controllers in achieving higher tracking accuracy, faster convergence, and improved stability under varying shading conditions. The study involves extensive simulations using a representative PV system model subjected to different shading scenarios. The results demonstrate that the proposed global MPPT controllers with the ASOA algorithm, when integrated with the modified MPPT algorithms, outperform the classical control techniques in terms of dynamic performance and response to partial shading conditions. The suggested ASOA-based fuzzy IC MPPT controllers can reach the MPP more quickly with a shorter settling time and a better tracking response. Furthermore, with a reduced settling time of about 1.9 % and an average power harvesting efficiency of over 97.9 %, ASOA-based fuzzy IC MPPT controllers offer the best harvesting characteristics. The controller exhibits superior tracking accuracy and stability, mitigating the effects of shading-induced multiple peaks in the P-V curve.

Microwave power harvesting using resonator-coupled double quantum dot photodiode

We demonstrate a microwave power-to-electrical energy conversion in a resonator-coupled double quantum dot. The system, operated as a photodiode, converts individual microwave photons to electrons tunneling through the double dot, resulting in an electrical current flowing against the applied voltage bias at input powers down to 1 fW. The device attains a maximum power harvesting efficiency of 2%, with the photon-to-electron conversion efficiency reaching 12% in the single-photon absorption regime. We find that the power conversion depends on thermal effects showing that thermodynamics plays a crucial role in the single-photon energy conversion. Published by the American Physical Society 2024

Engineering quantum criticality for quantum dot power harvesting

Abstract Coupling quantum-dot circuits to microwave photons allows one to study the photon-assisted quantum transport. Here, we revisit this typical circuit quantum electrodynamical setup by introducing the Kerr nonlinearity of photons. By exploiting a quantum critical behavior, we propose a powerful scheme to control the power harvesting efficiency in the microwave regime, where the driven-dissipative optical system acts as an energy pump. It drives electron transport against a load in quantum-dot circuit. The energy transfer and consequently the harvesting efficiency is enhanced near the critical point. As the critical point moves towards to low input power, the high efficiency within experimental parameters is achieved. Our results complement fundamental studies of photon-to-electron conversion at the nanoscale, and provide practical guidance for the design of integrated photoelectric device by the quantum criticality.

The performance investigation of flow-induced motion energy-harvesting by applying time-varying stiffness in the dynamic ocean environment

Ocean water exhibits periodic motion both temporally and spatially. However, no time-varying mechanism has been studied for harvesting energy from dynamic ocean. This paper presents an enhanced mechanism for harvesting the energy of ocean flows by applying time-varying stiffness adaptation in dynamic ocean environments, resulting in superior performance. By conducting numerical simulations and experiments, this study investigates the motion response and energy harvesting characteristics of a single oscillating cylinder equipped with time-varying stiffness. The research focuses on examining its behavior in both uniform flow and shear flow conditions, and presents several noteworthy findings. First, in comparison to impulse and trapezoid patterns, the sin-patterned time-varying stiffness demonstrates superior energy harvesting performance in both uniform flow and time-varying flow conditions. Second, the frequency of the sin-patterned time-varying stiffness is a critical parameter that influences the energy harvesting performance. Setting the sin-patterned time-varying stiffness frequency to ωv = 0.75ωn (natural frequency of constant stiffness) yields optimal performance under both uniform and time-varying flow conditions. At ωv = 0.75ωn, the energy-harvesting power can be increased by more than 30 times compared to the case of constant stiffness. Simultaneously, the oscillator's motion frequency experiences a reduction of over 40%. It is within this frequency range that the energy-harvesting power is maximized across the entire frequency spectrum. Third, as the frequency of sin-patterned time-varying stiffness increases, there is a decrease in both the energy harvesting power and efficiency. At a frequency of ωv/ωn* = 1.5, the advantage over the constant stiffness oscillator becomes negligible. Fourth, the energy harvesting performance of time-varying stiffness is superior in a time-varying flow condition compared to a uniform flow condition. The maximum energy harvesting power is achieved at ωv/ωn* = 0.75 in the time-varying flow condition, surpassing the corresponding value in the uniform flow condition. Fifth, the phase-shift resonance between the shedding frequency and the frequency of time-varying stiffness significantly enhances the energy harvesting performance of the time-varying stiffness oscillator. The optimal time-varying frequency is determined to have a phase difference of 0.15ωn. Sixth, the power harvesting efficiency can be improved by up to 1.5 times on average using the time-varying stiffness mechanism (sin-patterned, 10% additional power required) compared to state-of-the-art technologies employing constant stiffness. Finally, matching the form and dominant frequency of the excitation force with those of the time-varying stiffness can greatly improve the energy harvesting power and motion amplitude of the oscillator. This paper explores a performance-based approach to energy harvesting in dynamic ocean environments by applying sin-patterned time-varying stiffness with ωv = 0.75ωn.

Analysis and Design of RF Energy-Harvesting Systems With Impedance-Aware Rectifier Sizing

Because of the interaction between the internal blocks of an RF energy harvesting (RFEH) system, sizing a rectifier only for high power conversion efficiency (PCE) is insufficient for improving global power harvesting efficiency (PHE). This brief analyzes and sizes the rectifier by taking its input and output impedances into account with a two-port model that combines the rectifier AC and DC characteristics. The AC characteristic in this model is used for impedance-aware rectifier sizing. We target a low input-impedance rectifier for better impedance matching between the receiver antenna and the rectifier. The DC characteristic describes the rectifier power loss allocation and estimates its maximum power point. A proposed parasitic-aware matching network sizing methodology predicts the PHE is finally limited by Ohmic loss in the matching network at a low incident power level. For overcoming this limitation, this brief also analyzes the impact of multiple rectifier stages on RFEH with a high peak-to-average power ratio (high-PAPR) incident waveform for improving the PHE. We design an RFEH prototype with a sized 28nm CMOS two-stage cross-coupled rectifier. Measurement results show sensitivity as low as −28.3 dBm with a peak PHE of 31.1% at −16.5 dBm 2.45-GHz high-PAPR incident power. It has sufficient high output impedance to prevent reverse leakage without the need for an additional self-gating circuit.

A 30% Efficient High-Output Voltage Fully Integrated Self-Biased Gate RF Rectifier Topology for Neural Implants

This paper presents a fully integrated RF energy harvester (EH) with 30% end-to-end power harvesting efficiency (PHE) and supports high output voltage operation, up to 9.3V, with a 1.07 GHz input and under the electrode model for neural applications. The EH is composed of a novel 10-stage self-biased gate (SBG) rectifier with an on-chip matching network. The SBG topology elevates the gate-bias of transistors in a non-linear manner to enable higher conductivity. The design also achieves >20% PHE range of 12-dB. The design was fabricated in 65 nm CMOS technology and occupies an area of 0.0732-mm2 with on-chip matching network. In addition to standalone EH characterization measurement results, animal tissue stimulation test was performed to evaluate its performance in a realistic neural implant application.

A novel vibration energy harvesting system integrated with an inertial pendulum for zero-energy sensor applications in freight trains

With the development of the global economy, the demand for freight trains continues to rise, and the safety and maintenance of freight trains are essential. Therefore, sensors used for onboard monitoring of freight trains are vital components. However, the lack of onboard energy sources on freight trains makes the self-powering of sensors an urgent problem. In this paper, a novel renewable vibration energy harvesting system (VEHS) has been designed to provide electricity to sensors in freight train monitoring systems. The proposed VEHS mainly consists of three components: an energy input module, a motion transformation module, and an energy conversion module. The energy input module is composed of an inertial pendulum and a mass block. The movement transformation module integrates a novel and compact mechanical rectifier mechanism. The energy conversion module includes generators and energy storage devices. The wheel-rail coupled vibration is transformed into mechanical reciprocating rotation via the energy input module, and then into unidirectional mechanical rotation via the motion transformation module. Finally, the energy conversion module converts that mechanical energy of unidirectional rotation into electrical energy, and stores this micro-energy in a capacitor after rectification and boosting. Based on multi-body dynamics software and Simulink, a dynamic model was established to evaluate the vibration response of the system under different axle load and speed. Experiments revealed that the peak output power and energy harvesting efficiency of the VEHS were 1.04 W and 68.29 %, respectively. The RMS value of output power reaches 102.4 mW. In addition, this paper studies the application of the proposed VEHS to the China-Europe Express train. The results show that the system can be used to self-supply energy for freight train monitoring systems.

A review of recent advances in metaheuristic maximum power point tracking algorithms for solar photovoltaic systems under the partial-shading conditions

Several maximum power point (MPP) tracking algorithms for solar power or photovoltaic (PV) systems concerning partial-shading conditions have been studied and reviewed using conventional or advanced methods. The standard MPPT algorithms for partial-shading conditions are: (i) conventional; (ii) mathematics-based; (iii) artificial intelligence; (iv) metaheuristic. The main problems of the conventional methods are poor power harvesting and low efficiency due to many local maximum appearances and difficulty in determining the global maximum tracking. This paper presents MPPT algorithms for partial-shading conditions, mainly metaheuristics algorithms. Firstly, the four classification algorithms will be reviewed. Secondly, an in-depth review of the metaheuristic algorithms is presented. Remarkably, 40 metaheuristic algorithms are classified into four classes for a more detailed discussion; physics-based, biology-based, sociology-based, and human behavior-based are presented and evaluated comprehensively. Furthermore, the performance comparison of the 40 metaheuristic algorithms in terms of complexity level, converter type, sensor requirement, steady-state oscillation, tracking capability, cost, and grid connection are synthesized. Generally, readers can choose the most appropriate algorithms according to application necessities and system conditions. This study can be considered a valuable reference for in-depth works on current related issues.

Analysis on the power and bandwidth improvement of a frequency-tuning optimized SECE circuit

Efforts have been recently devoted to improving the performance of the piezoelectric energy harvesters (PEHs) from the electrical side, in both power harvesting efficiency and operating frequency bandwidth. The frequency-tuning concept for synchronous electric charge extraction (SECE) circuit is a feasible solution by simultaneously adjusting the energy extraction phase and the voltage reversal ratio, especially for highly coupled PEHs. However, in-depth analysis on the influence of the two tuning parameters on the electromechanical system is still not provided. In this paper, the frequency-tuning strategy has been introduced to the optimized SECE (OSECE) circuit in which the two-parameters tuning strategy can be realized more conveniently in comparison with the SECE circuit due to the common ground. Detailed analysis on the frequency-tuning OSECE technique reveals how the energy extraction phase and the voltage reversal ratio affect the system characteristics respectively. Moreover, special consideration is focused on the circuit quality factor which is shown to be a critical factor for determining the tuning parameters. Comparative studies have been performed between the proposed frequency-tuning OSECE (FT-OSECE), the frequency-tuning SECE (FT-SECE), the frequency tunable SECE (only varying the extraction ratio), phase-shift SECE (only varying the extraction phase), conventional SECE and OSECE. Good agreement between the theoretical and experimental results confirms the accuracy of the proposed model and FT-OSECE shows similar performance to FT-SECE with the aforementioned advantages of circuit implementations.

Solar energy harvesting efficiency of nano-antennas

The radiation efficiency of nano-antennas is a key parameter in the emerging field of IR and optical energy harvesting. This parameter is the first factor in the total efficiency product by which nano-antennas are able to convert incident light into useful energy. This efficiency is investigated in terms of the metal used as conductor and the dimensions of the nano-antenna. The results set upper bounds for any possible process transforming light into electrical energy. These upper bounds are the equivalent of the theoretical upper bounds for the efficiency of conventional solar cells. Silver shows the highest efficiencies, both in free space and on top of a glass (SiO2) substrate, with radiation efficiencies near or slightly above 90%, and a total solar power harvesting efficiency of about 60–70%. This is considerably higher than conventional solar cells. It is found that fine-tuning of the dipole dimensions is crucial to optimize the efficiency. & 2012 Elsevier Ltd. All rights reserved.

Solar energy harvesting efficiency of nano-antennas

The radiation efficiency of nano-antennas is a key parameter in the emerging field of IR and optical energy harvesting. This parameter is the first factor in the total efficiency product by which nano-antennas are able to convert incident light into useful energy. This efficiency is investigated in terms of the metal used as conductor and the dimensions of the nano-antenna. The results set upper bounds for any possible process transforming light into electrical energy. These upper bounds are the equivalent of the theoretical upper bounds for the efficiency of conventional solar cells. Silver shows the highest efficiencies, both in free space and on top of a glass (SiO2) substrate, with radiation efficiencies near or slightly above 90%, and a total solar power harvesting efficiency of about 60–70%. This is considerably higher than conventional solar cells. It is found that fine-tuning of the dipole dimensions is crucial to optimize the efficiency. & 2012 Elsevier Ltd. All rights reserved.

Efficiency of mono-stable piezoelectric Duffing energy harvester in the secondary resonances by averaging method. Part 1: Sub-harmonic resonance

The smart structures with the harmonic nonlinear vibration are used widely to broaden the frequency range of vibrations energy harvesting. In the paper, the potential of harvesting vibratory energy via a mono-stable Duffing energy harvester subjected to sub-harmonic excitation is investigated. The averaging method is used to derive the approximate solutions of the electromechanical linkage management equation system. The output voltage, power and energy harvesting efficiency of the harvester are investigated.

Scaling laws of electromagnetic and piezoelectric seismic vibration energy harvesters built from discrete components

This paper presents a theoretical study on the scaling laws of electromagnetic and piezoelectric seismic vibration energy harvesters, which are assembled from discrete components. The scaling laws are therefore derived for the so called meso-scale range, which is typical of devices built from distinct elements. Isotropic scaling is considered for both harvesters such that the shape of the components and of the whole transducers do not change with scaling. The scaling analyses are restricted to the case of linearly elastic seismic transducers subject to tonal ambient vibrations at their fundamental natural frequency, where the energy harvesting is particularly effective. Both resistive-reactive and resistive optimal electric harvesting loads are considered. The study is based on equivalent formulations for the response and power harvesting of the two transducers, which employ the so called electromagnetic and piezoelectric power transduction factors, Πcm2 and Πpe2. The scaling laws of the transduction coefficients and electrical and mechanical parameters for the two transducers are first provided. A comprehensive comparative scaling analysis is then presented for the harvested power, for the power harvesting efficiency and for the stroke of the two harvesters. Particular attention is dedicated to the scaling laws for the dissipative effects in the two harvesters, that is the Couette air losses and eddy currents losses that develop in the electromagnetic harvester and the material, air and dielectric losses that arise in the piezoelectric harvester. The scaling laws emerged from the study, are thoroughly examined and interpreted with respect to equivalent mechanical effects produced by the harvesting loads.

A DFT study on functionalization of acrolein on Ni-doped (ZnO)6 nanocluster in dye-sensitized solar cells

In this work, the functionalization of Acrolein on the Nickel-doped Zn6O6 (A-NiZn5O6) nanocluster with different adsorption configurations (C, M1 & M2) as the π conjugated bridging in dye-sensitized solar cells (DSSC) compared with the anchoring group [6,6] - phenyl-C61-butyric acid methyl ester (PCBM) have been investigated through (DFT/TD-DFT)) calculations by Gaussian 09 program. The interaction between the NiZn5O6 and the Acrolein has been explored through three functional groups are = O Carbonyl group (C), –CH Methyl group (M1), and –CH2 Methylene group (M2) of the Acrolein. The nature of the interaction between the Acrolein and NiZn5O6 has been exhaustively studied in terms of energy gap (Eg), global reactivity descriptors, molecular geometries, adsorption energy, the density of states, Mulliken atomic charges, molecular electrostatic potential, and the UV-Vis spectra for each adsorption site. The frontier molecular orbital analysis study indicated that all dyes could give a suitable electron vaccination from the LUMO orbital of A-NiZn5O6 to the HOMO orbital of PCBM. The adsorption process significantly improved the incident photon to the current conversion potency of the A-NiZn5O6. The determination of density functional theory calculations revealed that the C site of A-NiZn5O6 material was faced with a lower chemical hardness and energy gap (Eg) as well as a higher electron accepting power and light harvesting efficiency compared to other sites.

Analysis, Modeling, and Design of a 2.45-GHz RF Energy Harvester for SWIPT IoT Smart Sensors

Simultaneous wireless information and power transfer (SWIPT) is a flexible and cheap way to supply Internet-of-Things (IoT) smart sensors avoiding battery replacement. In this paper, we analyze, model, and design a 2.45-GHz RF energy harvesting (RFEH) system based on a discrete-component matching network (MN), a custom 65-nm CMOS cross-coupled rectifier, and an off-the-shelf storage-charging power management unit (PMU), which regulates the rectifier output voltage with maximum power point tracking (MPPT). We propose a reverse global analysis to model the RFEH. It allows an accurate prediction of the power harvesting efficiency (PHE) to directly size the MN and select the RFEH MPPT regulation ratio, at different incident RF power levels. We perform parasitic-aware RFEH design to take advantage of printed circuit board (PCB)/package capacitive parasitics at the rectifier input for optimizing the $\pi $ -MN with the help of the proposed RFEH modeling results. We show that this parasitic capacitance introduces a maximum bound on the real impedance at the rectifier input to ensure good impedance matching in practice. MPPT is used to help reach this target real impedance at given incident RF power, as the rectifier equivalent input impedance is a function of both its input and output voltages. Measurement results show a sensitivity as low as −17.1 dBm with a peak PHE of 48.3% at −3-dBm incident RF power. Global modeling, simulation, and measurement results demonstrate that the PHE is limited by PCB/package parasitic capacitance and that PCB/packaging technology improvement to reduce parasitic capacitance by 150 fF could boost the PHE up to 45% for a low incident RF power level of −10 dBm.

Numerical modeling and analysis of self-powered synchronous switching circuit for the study of transient charging behavior of a vibration energy harvester

Enhancement of power harvesting efficiency in piezoelectric energy harvesters through a non-linear electronic interfacing circuit is a well-established research area with potentially significant implications on piezoelectric energy harvesting efficiency. Among various types of synchronous switching circuits available in the literature, a self-powered electronic breaker is widely studied. Nonetheless, due to the interdisciplinary nature of this field, many of the currently available analyses tend to overlook and/or simplify certain aspects of this dynamical system. As a result, a comprehensive model of the system that considers accurate coupling effect of the interfacing and storage circuitry, as well as detailed analysis of the system during transient capacitor charging and energy harvesting operation is still missing. This paper thus aims at the problem of modeling a piezoelectric energy harvester with an Synchronized Switch Harvesting on Inductor (SSHI) circuit and a self-powered electronic breaker. A semi-analytic numerical model is proposed that is able to accurately simulate the operation of the system during transient process of charging an external storage device. Experiment validation confirms the accuracy of the proposed model considering the exact electromechanical coupling effect and transient charging dynamics with SSHI circuit and the model’s performance in estimating system transient behavior. Furthermore, a systematic parametric study is performed in order to analyze the effects of different system components on the energy harvesting efficiency during transient operation.

New type of motion trajectory for increasing the power extraction efficiency of flapping wing devices

Flapping wing devices represent a new type of renewable energy extraction technology that has the advantageous characteristics of simple structure, strong adaptability to surroundings, and little impact on the environment. This study numerically investigates the effects of vertical and elliptical airfoil trajectories on the power extraction efficiency of a flapping airfoil device using a transient numerical method based on the overset grid technique. The results are employed to propose a novel reversed-D airfoil trajectory that represents a composite of an elliptical trajectory in the first half of the motion cycle and a standard vertical trajectory in the second half of the motion cycle. The results show that for the elliptical trajectory, when the length of the half-axis in the vertical direction is fixed, the total power harvesting efficiency decreases with the increase of the horizontal half-axis length. In a certain frequency range, the decreased orders of the power extraction ability of the flapping wing are the upstream half-cycle elliptical trajectory, the vertical linear and the downstream half-cycle elliptical trajectory. Based on this understanding, we propose a new type of reversed-D motion trajectory. The power extraction efficiency of flapping wing devices operating in the reversed-D trajectory are investigated using both single and double airfoil designs. The results show that the power extraction efficiency of the single airfoil design moving along the reversed-D trajectory is greater than that obtained for the single airfoil moving along the standard vertical reciprocating trajectory within a specific range of frequency, and the increase is due mainly to an increase in the heave force. The power extraction efficiency of each airfoil in the double airfoil model moving along the reversed-D trajectory is less than that of a single airfoil moving along the vertical trajectory. However, the overall average power extraction efficiency is greater than that of a single airfoil moving along the vertical trajectory, and this increased efficiency is obtained over a larger frequency range than that of a single airfoil moving along the reversed-D trajectory. In addition, the increased efficiency of the double airfoil model is greater in the low frequency region. The proposed reversed-D trajectory facilitates the flexible arrangement of multiple airfoils in a flapping wing design. As such, the proposed reversed-D trajectory provides a promising new methodology for designing flapping wing devices with high power extraction efficiencies.

A study of harvested power and energy harvesting efficiency using frequency response analyses of power variables

Abstract Frequency response analysis of field variables such as force, displacement/velocity, voltage was conducted in the previous work to study harvesting vibration energy under the base excitation of the random and sinusoidal signals. This paper proposes a unique method for conducting frequency response analysis on power variables under a new unified theoretical framework to determine the time averaged harvested power or energy harvesting efficiency under the excitation of the random and sinusoidal signals. The uniqueness of the method is to directly measure and calculate the time averaged output power and efficiency for piezoelectric and electromagnetic vibration energy harvesters under different excitations regardless of the dimensions or sizes of the vibration energy harvesters. This paper has studied the frequency responses of power variables and their mean/dc values and illustrated the relationships of the mean/dc values with the mean harvested power or energy harvesting efficiency.

A battery-less BLE smart sensor for room occupancy tracking supplied by 2.45-GHz wireless power transfer

Wireless power transfer (WPT) has emerged as a solution for supplying smart sensors for long-term battery-less deployment. Because the amount of power harvested by the smart sensor is limited due to WPT path loss, the optimization objective is twofold: achieving ultra-low-power operation for the sensing task and improving the harvesting efficiency even at low incident power. In this paper, we focus on the use case of a Bluetooth LE-connected motion detection system supplied by 2.45-GHz RF power. The full system (RF energy harvester, power management, sensor transducer and interface, control, data processing and wireless transmission) is implemented using low-power off-the-shelf components. In the sensing sub-system, ultra-low-power operation is achieved by the duty-cycling of the sensor interface and by an event-driven scheme for communication. In the harvesting sub-system, the design of the matching network and rectifier, combined with maximum power point tracking (MPPT), is optimized for increasing the power harvesting efficiency (PHE) at low incident power. Measurements show a total reduction in the power consumption for the sensing sub-system by a factor 20. When using custom WPT waveform with high peak-to-average power ratio, the RF energy harvester is functional with an incident RF power starting from −20 dBm. The smart sensor is able to perform its motion-detection task with an incident power as low as −17.3 dBm.