Bidirectional Leaky-Wave Antenna Based on Dielectric Image Line for Remote Vital Sign Detection at mm-Wave Frequencies

Abstract

A bidirectional leaky wave antenna (LWA) with beam scanning capabilities was developed based on the dielectric image line for single-tone continuous-wave Doppler radar (DR) for remote vital sign monitoring (RVSM) in a dynamic environment. It consists of a conductor-backed copper dielectric image line with two of the same dielectric layers mounted on top of each other for performance improvement. A RO6010 substrate with high permeability is used for the top two layers. The bottom layer is a RT/duroid 5880 low permittivity substrate stacked on top of the copper DIL to prevent higher order modes from being excited in the DIL channel. The dominant mode of the DIL is perturbed by making holes periodically in the DIL, and fast-wave space harmonics are generated. The scanning range of the proposed antenna through the broadside is 70.19 • (−42.49 • to 27.7 • ) with an impedance bandwidth of 15 GHz (50-65 GHz), an optimum gain in the fast wave area ranging from 15.5 dBi to 19.79 dBi and an efficiency of 83.8% at 57.5 GHz. Detailed RVSM tests have been performed with the proposed antenna system. It is shown that by adjusting the operating frequency from 50 GHz to 65 GHz, multiple targets' breathing rates (BR) and heart rates (HR) can be detected within 70 • of the angular range.INDEX TERMS Dielectric image line (DIL); doppler radar sensors; Frequency scanning; Leaky wave antenna; remote vital sign monitoring.

Multi-Layer Beam Scanning Leaky Wave Antenna for Remote Vital Signs Detection at 60 GHz

“…A very good agreement between the measured results and the predicted and simulated results has been achieved. This work is an improvement from the antennas already published in [16,17]. The reported antenna bandwidth, maximum gain, and beam scanning range in [16] are 3.78 GHz, 20.35 dBi, and 12 • , respectively, compared to 16 GHz, 24 dBi, and 30 • in this work.…”

“…Additionally, our proposed antenna operates with an enhanced realised gain of 24.3 dBi and radiation efficiency of 95.5% compared to relevant work from the literature. The achieved bandwidth of our work is more limited compared to [17], which is due to the well-known trade-off between gain and beam aperture, which explains the more limited range of our antenna compared to [17]. However, the obtained realised gain of our proposed design makes it suitable not only for RVSM but for a number of other applications as well, such as 5G communications and IoT.…”

“…The reported antenna bandwidth, maximum gain, and beam scanning range in [16] are 3.78 GHz, 20.35 dBi, and 12 • , respectively, compared to 16 GHz, 24 dBi, and 30 • in this work. The dielectric image line antenna of [17] has a maximum gain of 19 dBi as compared to 24dBi gain of the proposed multi-layer LWA. Due to this high gain, the multiplayer LWA in this work has more advantages in terms of distance applications, such as radar, and many IoT applications.…”

CEEMDAN-ICA-Based Radar Monitoring of Adjacent Multi-Target Vital Signs

“…In order to separate targets in the same range cell, it is necessary to estimate the angleof-arrival (AOA) of different targets. This technique can be further divided into hardwarebased methods [7][8][9][10][11][12][13] and software-based methods [14][15][16][17]. Hardware-based methods obtain non-contact vital signs information by designing the radar hardware structure.…”

“…Nosrati et al developed a 2.4 GHz dual-beam phased array continuous wave multi-input multi-output (MIMO) radar, which use phase shifters for controlling the phase of each receiving channel [13]. In [12], Mingle et al designed a bidirectional leaky wave antenna (LWA) with beam scanning.…”