Most medical instruments invented to measure human heart activities, such as electrocardiograms (ECGs), rely on contact electrodes. This causes discomfort and limits application scenarios. Remote acquisition of μV-level bioelectrical cardiac signals through ECG measurement is theoretically challenging. Based the analysis magnetic resonance imaging volume change hearts, we found that a single radar sensor can be used remotely detect Doppler cardiogram (DCG) at distance up 1 m, by retrieving...

Cardiogram is one of the most important factors for health assessment. As a new expression cardiograms, Doppler cardiograms (DCGs) detected remotely via radar sensor (DRS) provide rich details heart motion. However, existing techniques measurement DCG requires that subject holds his/her breath to avoid disturbance caused by respiration. To realize accurate detection DCGs in presence respiration, high-linearity <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML"...

In view of the differences and limitations cognitive abilities both sides network security attack defense, current defense decision-making methods using game theory are mostly based on assumption that participants completely rational, which is difficult to apply actual scenarios, resulting in poor practicality decision-making. order better fit with scenario imperfect rational games, we evolutionary describe evolution process games under rationality, extend static analysis traditional into a...

Personal devices such as smartphones and tablets are rapidly becoming personal communication, information, control centers. Apart from multitouch screens, human gestures considered a new interactive human-smart device interface. In this work, we propose noncontact solution to implement hand gesture recognitions for smart devices. It is based on continuous wave, time-division-multiplexing (TDM), single-input multiple-output (SIMO) Doppler radar sensor that can be realized by slightly...

A simple zinc salt additive strategy to improve the quality of CdS and Sb 2 S 3 films for photovoltaic application.

An eclipse attack is a common method used to the blockchain network layer; however, detecting attacks challenging, and performance of existing methods inadequate due uneven sample distribution, incomplete definition discriminating features, weak feature perception. Thus, this paper proposes an traffic detection based in custom combination features deep learning. To describe behavior characteristics more accurately, attribute there levels are defined with method. Here, downstream described...

Robust contactless Doppler cardiogram (DCG) detection in practical scenarios encounters challenges arising from radar hardware performance limitations and signal processing effectiveness. In this work, through an analysis of IQ mismatch signals, we proposed a novel vectors analytic demodulation (VAD) method, which employing the original to generate four basis vector linearly obtain target's differential displacement signal. Simulation experiments confirm efficacy VAD algorithm achieving...

Traffic speed forecasting is one of the important issues in intelligent transportation system, which related to traffic management planning. The existing studies tend use single models forecast speed, and cannot completely extract complex information sequence. This research proposes a new hybrid model based on reinforcement learning for accurate speed. contains LSTM network GRU as predictors in-depth mining characteristics data uses integrate results two predictors, combining advantages...

Doppler radar uses phase demodulation to extract the target displacement motion contained in of echo signal. The performance is vulnerable additive Gauss noise. Especially when signal-to-noise ratio (SNR) extremely low scenarios long-range or subtle sensing, it may be impossible correct information. In this article, a method with high robustness against noise proposed for accurate reconstruction. Mathematical derivations are performed analyze effect on demodulation, and shows that influence...

Radar interferometry is widely used for detecting versatile displacement motions. The conventional techniques motion extraction depend on the quadrature <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$I/ Q$ </tex-math></inline-formula> signals, and proper calibration of signals a necessary step to ensure accurate detection. However, process architecture inevitably add up system complexity. In this article,...

To date, 3-D radar imaging of moving objects in a multipath coordinate space close to antennas remains technical challenge. In this work, we demonstrate the implementation such motion based on continuous-wave, multiple-input multiple-output (MIMO) Doppler sensor (DRS). Working with time-division-multiplex (TDM) scheme, portable, cost-effective DRS is bistatic system one transmitting and receiving channels, radio frequency (RF) switch each channel toggling between two antennas. Assisted by...

As a prognostic indicator in heart failure patients, Cheyne-Stokes respiration (CSR) occurs both day and night. However, current methods for CSR detection still have limitations convenience long-term monitoring. This paper presents wireless biomedical millimeter-wave radar as potential technique assisting monitoring by detecting CSR. With the placed at bedside, it can offer cardiopulmonary recordings of patients around clock, excelling sensitivity, noncontact detection, constant Clinical...

This paper proposes a novel sensing system for noninvasive and continuous estimation of blood pressure (BP), which is based on custom designed wearable 120 GHz Doppler radar sensor. With signals detected from brachial artery at the elbow, moving trajectory pulses can be accurately demodulated with micrometer accuracy, thus reflective pulse transit time (RPTT) obtained prediction model to estimate pressure. Clinical trials have been launched invasive as reference. The experimental results...

A novel radar sensing system for non-contact and continuous detection of heart sound is proposed in this paper, which a custom designed 120 GHz interferometric radar. The moving trajectory the pulses can be accurately demodulated based on signals, thus sounds reconstructed. Experiments have been carried out with electrocardiogram (ECG) phonocardiogram (PCG) as reference. results show pulse signatures to an accuracy micrometer level detected by sensor, reconstructed visually acoustically...

In this work, we proposed and verified that a noncontact measurement to the human cardiogram could be implemented based on inner connection between bioelectrical signals control diastole systole of hearts volume change atriums ventricles taking place at surface skin. A K-band, board-integrated, highly linear sensitive Doppler radar sensor was designed detected such weak motions. Experimental results showed by linearly retrieving information from scattered skin, can measured. While...

As the most important organ of human body, heart has many measures and indicators to assess cardiac function in clinic. Ventricular systolic time intervals (STIs) are major relevance providing crucial information regarding cardiovascular state. However, existing measurement technologies costly, complicated operate, also require contact sensors. Based on model principle Doppler cardiogram (DCG), differential DCG (D-DCG) quadratic D-DCG (QD-DCG) carry aortic pressure (AP) by which STIs can be...

Every year many newborns will have apnea which easily leads to a lower level of oxygen saturation i.e. hypoxia. Traditional methods for monitoring usually involve skin contact, so they might cause discomfort or even damage the infants. In this paper, noncontact infant cardiopulmonary technique aiming at prompt detection is proposed based on K-band continuous-wave biomedical radar sensor system, custom designed be DC-coupled with an adaptive digital tuning function. Since chest motions...

A feature-based filtering algorithm is proposed to solve the difficult problem of indoor human body positioning. The based on multiple-input multiple-output (MIMO) frequency-modulated continuous wave (FMCW) radar, including noise floor removal in time domain, adaptive mean cancellation frequency and non-coherent accumulation for all virtual array elements. As different postures body, such as standing posture, sitting lying movement, etc., raw radar data processed remove obtain an enhanced...