An impulse radio duty-cycled radar with ultra-wideband VCO using frequency hopping technique

Abstract

This paper presents a pulse-based radar with ultra-wideband voltage controlled oscillator for vital-sign application. A series of digital-assisted duty-cycled probing pulses with frequency hopping technique is proposed to mitigate unwanted narrowband interferences, thereby increasing overall system signal-to-noise ratio and then enabling high resolution detection. The RF generator is utilized by an on-chip VCO with the characteristic of wide-band response by digitally switching loaded capacitor array for frequency hopping. The conventional ultra-wideband channel is further divided into several sub-channels for vital-sign sensing. An impulse radio Doppler radar is implemented and integrated with the digital-assisted oscillator to detect physiological information.