Test setup and spurious replicas identification in time-quantized pseudorandom sampling-based ADC in SDR multistandard receiver

Abstract

Software defined radio (SDR) multistandard receiver is an enabling technology for radio evolution. The time-quantized pseudorandom sampling (TQ-PRS) is an advantageous processing for SDR multistandard receiver design. The TQ-PRS allows aliases attenuation leading to a relaxed receiver baseband stage. In this paper, the authors focus on experimental proof of concept of the TQ-PRS-based analog-to-digital converter (ADC). The spectrum analysis of the test results shows spurious replicas which are not present in simulation results. The presented investigations show that the spurious replicas are coming from a pseudorandom delay with the same periodicity as TQ-PRS clock. A solution based on sharing receiver channel selection filter for spurious attenuation is proposed.