Ultra-Wide Patch Antenna Array Design at 60 GHz Band for Remote Vital Sign Monitoring with Doppler Radar Principle

Abstract

In this paper, ultra-wide patch antenna arrays have been presented at 60 GHz band (57.24-65.88 GHz) with improved gain and beam-width capabilities for remote detection of respiration and heart beat rate of a person with Doppler radar principle. The antennas measured and simulation results showed close agreement. The breathing rate (BR) and heart rate (HR) of a 31-year-old man have been accurately detected from various distances ranging from 5 to 200 cm with both single-antenna and dual-antenna operations. In the case of single-antenna operation, the signal is transmitted and received with the same antenna, whereas in dualantenna operation, two identical antennas are employed, one for signal transmission and the other for reception. It has been found that in case of the single-antenna operation, the accuracy of the remote vital sign monitoring (RVSM) is good for short distance; however, in the case of the dual-antenna operations, the RVSM can be accurately carried out at relatively much longer distance. On the other hand, it has also been seen that the visual results are more obvious with higher gain antennas when the radar beam is confined just on the subject's body area.

Different Antenna Designs for Non-Contact Vital Signs Measurement: A Review

“…However, some drawbacks were identified. In [23], a test was performed to evaluate the system performance, using a single antenna or two separate antennas for TX and RX. Results showed that a single antenna has good accuracy in vital signs' detection, considering a short-range.…”

“…In [23], the authors carefully selected the microstrip type of antenna for their experiments. Apart from having an acceptable gain, microstrip antennas can also be embedded on chip devices, which reduces the total size of the system and use a low-cost fabrication process.…”

Remote Monitoring of Vital Signs in Diverse Non-Clinical and Clinical Scenarios Using Computer Vision Systems: A Review

“…The Doppler effect is an active noncontact method that can detect subtle chest movements due to cardiorespiratory activity. In this method, vital signs are extracted using a Doppler radar [19,20], or laser sensors [21] as well as digital signal processing (DSP) techniques [22] where the phase shift between the transmitted waves and the reflected received waves from a region of interest (ROI) are calculated. There are three types of Doppler-based methods-Doppler with electromagnetics [23,24], lasers [25,26], and ultrasonics [27][28][29].…”

Evaluation of gain enhancement in improved size microstrip antenna arrays for millimetre-wave applications

“…In the modern point to point wireless communications, it is very common to enhance the gain of microstrip antennas by constituting arrays of multiple patch elements due to the simplicity and cost effectiveness of this approach [1][2][3][4][5][6][7][8][9][10][11][12][13]. However, at microwave and lower frequencies (<30GHz) this technique is limited by the exceptionally large antenna size acquired for high gain (>20dBi) arrays [6].…”

“…However, at microwave and lower frequencies (<30GHz) this technique is limited by the exceptionally large antenna size acquired for high gain (>20dBi) arrays [6]. On the other hand, at mm-wave frequencies high gain MPAAs can fit within a small footprint due to the small form factor [7][8][9][10][11][12][13][14][15]. However, at mm-wave frequencies this approach is restricted by the declined antenna efficiency and gain due to the substantial power losses commenced by the extended feeding line network which is vital to deliver matched electrical signal to each of the radiating elements [1][2].…”