Microwave sensors have recently been introduced as high-temporal resolution sensors, which could be used in the contactless monitoring of artery pulsation and breathing. However, accurate and efficient signal processing methods are still required. In this paper, the matrix pencil method (MPM), as an efficient method with good frequency resolution, is applied to back-reflected microwave signals to extract vital signs. It is shown that decomposing of the signal to its damping exponentials fulfilled by MPM gives the opportunity to separate signals, e.g., breathing and heartbeat, with high precision. A publicly online dataset (GUARDIAN), obtained by a continuous wave microwave sensor, is applied to evaluate the performance of MPM. Two methods of bandpass filtering (BPF) and variational mode decomposition (VMD) are also implemented. In addition to the GUARDIAN dataset, these methods are also applied to signals acquired by an ultra-wideband (UWB) sensor. It is concluded that when the vital sign is sufficiently strong and pure, all methods, e.g., MPM, VMD, and BPF, are appropriate for vital sign monitoring. However, in noisy cases, MPM has better performance. Therefore, for non-contact microwave vital sign monitoring, which is usually subject to noisy situations, MPM is a powerful method.

Recent low power implant to off‐body communication systems uses both medical implant communication services (MICS) and industrial, scientific, and medical (ISM) frequency bands. In these systems, MICS band and ISM band (2.45 GHz) are dedicated for data transmission and wake‐up signal, respectively. This dual band operation which incredibly extends the life time of battery forces designers to use dual band antennas in both implant and off‐body sides. In this study, a dual band implant electrically coupled loop antenna is proposed. This antenna as dual of planar inverted‐F antenna is a magnetic antenna with inherently low near zone electric field and therefore produces low specific absorption rate (SAR) inside the body. The antenna is miniaturised using a lumped capacitor. In spite of small size of 5 × 5 × 3 mm3, the simulated 1 g average SAR is smaller than reported dual band implant antennas in both frequency bands and makes the proposed antenna a good candidate for implant applications.

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