A ΔΣ IR-UWB radar with sub-mm ranging capability for human body monitoring systems

This paper describes a ΔΣ modulation based ranging method for the IR-UWB radar system. To relax the phase resolution requirement of the delay line in the receiver, two coarse timing boundaries of the delay line are used to form a bilevel quantizer which can be the part of a 1-bit ΔΣ oversampling TDC. Also, a digital phase rotator circuit is designed to provide an unlimited phase capture range. Simulation results show that the proposed ΔΣ IR-UWB radar can achieve sub-mm ranging resolution with good matching assumed.