An Innovative Architecture for a Non-Ideal Parallel Sub-Sampling Wireless Receiver

Abstract

The main bottleneck in broadband reconflgurable (or software-defined) radio systems is the fast analog-to-digital converters (ADC) required to capture the entire system band. Such ADCs are typically costly, consume a lot of power, and have non-ideal transfer characteristics, as well as a limited spurious-free dynamic range (SFDR). This cost problem is compounded in multi-antenna and MIMO (multiple input, multiple output) systems where the entire RF chain, including the ADC, must be replicated for every receiving antenna. This paper presents an architecture where each ADC in a MIMO transceiver is replaced by several slower and less expensive ADCs, effectively partitioning the sampling problem. Furthermore, the combining of the subsampled information streams is done in a dynamically adaptive fashion, in conjonction with the standard space-time processing performed in MIMO systems. Among the many potential advantages of this arrangement, the ability to track and compensate for sample clock jitter is emphasized in this paper.