Portable Low-Power Fully Digital Radio-Frequency Direct-Transceiving See-Through-Wall Radar

A see-through-wall (STW) radar system based on a direct digital-logic radio-frequency (RF) pulse generator and an equivalent-time direct RF-sampling receiver chipset is proposed. Both the transmitter and the receiver of the radar system are both operated in the digital domain, considerably simplifying the design complexity and the difficulty of signal processing. In terms of data processing, we replace the conventional analog-domain mixing (self-mixing) and digital-domain mixing (self-mixing) modes by taking the absolute value to down convert the signal to the baseband. Thus, the mixer and the local oscillator are removed, which significantly reduces the power consumption while simplifying the signal processing. To verify the effectiveness of the proposed method, a relevant radar chipset was designed in Taiwan Semiconductor Manufacturing Company (TSMC) 65nm process. The prototype radar has a maximum transmission power of 17 dBm and a maximum equivalent sampling rate of 20 GS/s. The detection distance of the STW radar is 8 m with 30.0 cm thick wall, while the respiratory rate of the stationary life is measured through the wall.