Specification of the ADC interface for an interference robust UWB impulse radio

In this paper, the Analog to Digital Converter interface of a pulse based UWB system operating in the presence of strong interferer is specified. The minimum number of quantization bits is determined for interfering signals caused either by in-band or out-of-band service signals and for different front-end realizations. While for an undisturbed UWB communication link 4 quantization bits are sufficient, up to 14 bits are necessary for an UWB short range communication distance from 3-15 meters for a `worst-case' interference scenario. Results show that a non-linear Analog to Digital Converter approach can significantly reduce the number of required bits from 14 to 8 bits. Fast Fourier Transformation processing methods have also been investigated in terms of processing load and influence on receiver sensitivity. We show that, with a moderate 32-points Fast Fourier Transformation resolution that enables simple serial processing, we can implement efficient interference notch filtering with negligible Bit Error Rate degradation of less than 0.5 dB at a Bit Error Rate of 10^-3.