Signal-adaptive and time-dependent analog-to-digital conversion rate in a ranging receiver

Abstract

An integrated circuit may include a ranging receiver that includes an analog-to-digital converter (ADC) having a time-variant sampling or data rate. Notably, the sampling rate may be increased when a return signal is detected by the ranging receiver. For example, the return signal may be detected using a matched filter (such as a correlation of the return signal and a target signal) and a comparator having a time-variant threshold. The time-variant threshold may be decreased as a function of time after a transmit signal is output in order to track the channel response, such as a decrease in the return signal amplitude for objects at larger ranges. Alternatively or additionally, the sampling rate may be increased based at least in part on a predefined function (such as a closed-form expression or a stepwise function, e.g., a stairstep function) after the transmit signal is output.