Abstract: Nyquist folded bandpass sampling receivers are disclosed that utilize wideband filters and modulated sampling clocks to identify received signals. In operation, multiple Nyquist zones are allowed to fold on top of each other during sampling. Because the RF sampling clock is modulated, separate frequency modulations can be induced within each Nyquist zone. The signals that are folded together from different Nyquist zones can then be identified and distinguished. In particular, when the Nyquist zones fold on top of each other, the different signals from different Nyquist zones can be separated and identified based on the fact that the added modulation is different for each Nyquist zone. Thus, by using one or more clock modulations to induce frequency modulations that are Nyquist zone dependent, multiple Nyquist zones can be aliased together while still allowing for signals from different Nyquist zones to be separated and identified. Other variations and implementations are also described.

Abstract: Nyquist folded bandpass sampling receivers are disclosed that utilize narrow band filters in parallel with wideband filters to enhance reception of ultra wideband (UWB) pulses. The addition of the narrow band filter facilitates the reception of ultra wideband signal pulses and, therefore, extends the Nyquist folding bandpass sampling receiver to allow improved processing of ultra wideband (UWB) pulses. RF sampling circuitry utilizing a modulated sampling clock signal can then better capture UWB pulse signals.

Abstract: An interpolation circuit (10) generates a plurality of intermediate amplitude values linearly related to two consecutive signal amplitude values using a system of adders and memory elements. A first stage (64) of the interpolation circuit calculates a one-half amplitude value; a second stage (66) calculates one-fourth and three-fourths amplitude values, and a third stage (68) calculates one-eighth, three-eighths, five-eighths, and seven-eighths amplitude values. A comparator (14) receives a threshold value (32) and compares each of the intermediate amplitude values to the threshold value. A decoder (16) generates a time of arrival adjustment value that is subtracted from a low resolution time of arrival to generate a high resolution time of arrival.