Device-free indoor localization and tracking using commercial millimeter wave radars have attracted much interest lately due to their non-intrusive nature high spatial resolution. However, it is challenging achieve accuracy rich multipath reflection occlusion in environments. Static objects with non-negligible reflectance of mmWave signals interact moving human subjects generate time-varying ghosts shadow ghosts, which can be easily confused as real subjects. To characterize the complex...

This article presents a fully integrated 100-GHz continuous-wave Doppler radar transceiver with the double-sideband low-intermediate-frequency (IF) architecture for mechanical vibration and vital sign detection. Fabricated in 65-nm CMOS process, whole chip consumes 262 mW size of 0.9 mm $\times2.0$ mm. Instead utilizing fundamental voltage controlled oscillator (VCO) chip, push-push frequency doubler 50-GHz external source is adopted to drive transceiver. Under dedicated design on system...

A low-cost multilayer antenna-in-package solution, using the standard printed-circuit-board (PCB) process, is proposed for 60-GHz-phased array system. The design procedure focuses on overcoming fabrication restrictions and realizing a low-cost, broadband, compact reliable package solution. stack-up structure consists of three laminates two bondply layers, with which antenna element, vertical quasi-coaxial via transition, feedline, power, low-speed interfaces are realized. An aperture-coupled...

A broadband, low-cost, high-gain, multilayer differential antenna without air cavity is proposed for the 60-GHz phased array system. By using standard low-cost printed circuit board process, a element and 16-element prototype are implemented. To improve bandwidth gain, superstrate float rectangular ring designed. The can enhance vertical radiation, suppressing horizontal radiation reducing mutual coupling. Without any embedded cavity, robust against process variation, which verified in...

In this paper, we propose a new envelope detection (ED) method to reduce the analog-to-digital converters' (ADCs) sampling rate from 20 kHz Hz in double-sideband low-intermediate-frequency (IF) continuous-wave Doppler radar. Compared with conventional synchronous demodulation (SD) method, which typically consumes large amount of ADC resources, proposed ED can achieve same results on both mechanical vibration and human vital sign detection. Meanwhile, paper also describes detail hardware...

The single-parameter scaling hypothesis relating the average and variance of logarithm conductance is a pillar theory electronic transport. We use maximum-entropy ansatz to explore particle, or energy density $ln\mathcal{W}(x)$ at depth $x$ into random one-dimensional system. Single-parameter would be special case in which $x=L$ (the system length). find result, confirmed microwave measurements computer simulations, that independent $L$ equal $\ensuremath{-}x/\ensuremath{\ell}$, with...

Most existing RF-based vital sign monitoring systems either assume that a human subject is stationary or discard measurements when motion detected in order to output reliable respiration rates and heart rates. Such an assumption greatly limits the usability of these practice. Even during sleep, one can undergo various body states including turns involuntary twitches light motionlessness deep abnormal limb movements due sleep disorders such as restless legs syndrome. In this work, we develop...

Based on the double-sideband low intermediate-frequency (IF) architecture, a 100-GHz CMOS radar transceiver is realized for non-contact small mechanical vibration and biological vital sign detections. A 50-GHz push-push frequency doubler with off-chip VCO used to generate local oscillator (LO) signal transmitter (TX) receiver (RX). Injected by 40-mV 1-kHz sinusoidal IF carrier input, TX achieves relatively constant 4-dBm output power over 93- 105 GHz. Under -36-dBm RF input from 95 104 GHz,...

In the field of noncontact sensing, both continuous-wave (CW) Doppler radar and frequency-modulated CW (FMCW) have their own superiorities. A combination these two modes would be a suitable choice to accommodate various application scenarios. This article presents 60-GHz hybrid FMCW-Doppler transceiver fabricated in 65-nm CMOS process. An on-chip frequency quadrupler driven by 15-GHz external signal source is utilized for waveform generation. Based on operating modes, robust I/Q imbalance...

Caused by inappropriate allocation of the interstage power mismatches during broadband matching, boosted dynamic dc current frequency doubler (FD) would deteriorate efficiency. To tackle this issue, an efficiency-optimized matching strategy is proposed allocating all desired low-frequency ahead push-push (PP) pair, which not only keeps a output but also reduces and improves efficiency over entire operating bandwidth simultaneously. further enhance 2nd harmonic (HR2) power, fourth-order notch...

This letter presents a fully integrated 16-element phased-array transceiver (TRX) supporting dual-polarization multi-input multi-output (DP-MIMO). transmitting/receiving (T/R) switches are embedded for time division duplexing (TDD) operation. High-linearity bidirectional variable gain amplifiers (Bi-VGAs) and passive phase shifters (PSs) designed compact area low power consumption, respectively. Fabricated in 65-nm CMOS process, this TRX occupies an of 25.76 mm <inline-formula...

A 60-GHz joint radar–communication (JRC) transceiver is introduced in this letter. Benefiting from a reconfigurable dual-mode Gilbert cell, which could not only operate as an upconversion mixer for the baseband signal but also be configured amplifier LO signal, highly reused JRC architecture realized. In radar mode, instead of utilizing narrowband IF chirp modulation scheme, widely adopted previous systems, work, wideband generated directly chain applied both transmitting and direct RF...

This letter presents a frequency reconfigurable low-noise amplifier (LNA) for 5G 28-/39-GHz bands applications. In the proposed LNA, wideband input common-source is designed to cover both 28-and 39-GHz bands, and following two parallel switchable common-gate amplifiers are leveraged split RF signal into independent paths. Thus, output single-band could be optimized flexibly at each target operating band with area-efficient magnetic-capacitive coupling transformer-based matching networks,...

A <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$W$ </tex-math></inline-formula> -band integrated tapered array antenna with series feed is presented. To reduce the fabrication cost, designed on a single layer standard printed circuit board (PCB) process. In design, novel coplanar waveguide (CPW) feeding structure proposed to simplify network and by avoiding three-way power divider via Considering...

The requirement to detect weak physiology motion by Doppler radar arises new architectures utilizing low intermediate frequency (IF) achieve high signal-to-noise ratio (SNR). With the help of IF, significant information is modulated IF domain, promoting system's resistivity both noise impact and AC distortion. However, for simultaneously sampling outputs carrier would waste more analog digital converter (ADC) resources in a digitally assisted system. In this paper, we propose method envelope...

A 100-GHz continuous-wave (CW) Doppler radar transceiver is proposed for recognizing an adult bullfrog's unique respiratory pattern, which contains buccal and lung ventilations. With two horn antennas, the detection system working at 99 GHz set up, body vibration caused by motion burst detected. According to results detecting front side of bullfrog, ventilation shows a regular moving rhythm around 72 bpm under 23°C. By flank bullfrog from right direction, are successfully recognized based on...

This letter presents a three-stage 60-GHz phase-invariant variable gain low-noise amplifier (VG-LNA) with accurate tuning step and large range. A single-ended cascode is adopted as the first stage to integrate transmit/receive (T/R) switch achieve wideband input matching. Besides, interpolation techniques, by combining three different cells, stacked gain-boosting proposed realize wide-range dB-linear functions simultaneously, showing merits of low layout logic control complexity. Fabricated...

Fine-grained vital sign monitoring in emergency care is crucial for accurately assessing patient conditions, predicting disease progression, and formulating effective rescue plans. In non-hospital settings, limited equipment often necessitates manual observation of respiration heartbeat, which can lead to significant errors. Contactless using wireless signals offers a promising alternative. Unlike traditional systems that require stationary devices contactless sensing, handheld are more...

A frequency-modulated continuous-wave (FMCW) chirp generator serves as the pivotal building block for short-range 3D imaging radar systems, which have been widely utilized in medical and security applications. To enable quick precise scanning with sub-millisecond snapshot duration sub-centimeter depth resolution a 79GHz large-scale MIMO system, composes of hundreds TX/RX elements, FMCW must generate chirps about $1 \mu s$ operate $\gt15$ GHz bandwidth (BW), necessitating an ultra-fast slope...

Based on the phase evaluation method, frequency modulated continuous wave (FMCW) radar has been used for non-contact range tracking with a high accuracy. However, due to finite resolution, FMCW is still vulnerable target's adjacent clutters which would distort history. Especially, when are no longer stationary, common in biological heartbeat detection scenario, general stationary clutter removal methods may not work properly. In this paper, novel method proposed reduce vibrating by...