Unique measurement and modeling of total phase noise in wideband receiver

摘要

RF receivers are common in many modern electronic systems such as wideband beamforming and radar systems. Typically a receiver consists of an analog front-end followed by a digitizer. Note that improvement of analog circuits has proven difficult, and the overall receiver performance is usually limited by the analog front-end. Therefore, achieving low-distortion reception is highly desired, especially for wideband receivers. Among all performance degradation contributors, phase noise and jitter are especially troublesome since they cause random errors which are difficult to compensate. Each individual RF device contributes to phase noise, while the analog to digital converter (ADC) tends to effect time jitter. To quantify the system performance, it is desired to know the accumulated effect of individual phase noise sources and jitter. Under linear channel assumption, the total effect of all phase noise and jitter contributions along a channel can be represented by an accumulated phase noise at the ADC's output, called total phase noise. This paper focuses on measuring and modeling the total phase noise relying on unique optimization approaches. In contrast to traditional phase noise measurement that typically relies on hardware, a digital approach is proposed and developed. In particular, a measurement-based phase noise model is created. A modified spectrum fitting technique based on optimization is proposed and examined. It is confirmed that the total phase noise satisfies wide sense stationary (WSS) Gaussian process model.