UWB Radar signal capture and analysis

As radar designers produce ever wider systems there comes a point where the digitizers found in high dynamic range measurement systems, such as spectrum analyzers are not fast enough to capture the instantaneous bandwidth of the signals they are measuring. This paper is intended to enable designers working with signals of more than a couple hundred megahertz of instantaneous bandwidth (BW) to understand the measurement capabilities offered in today´s high bandwidth, high sample rate oscilloscopes as they relate to modern radar signal capture and analysis. The discussion will include both the capture of the pulse characteristics as well as the chirp or coded information within the pulse. The techniques discussed, while framed around radar, are based in core acquisition and measurement technology building blocks making the discussion applicable to any ultra wideband technology. The paper will specifically discuss how to determine and control various aspects of dynamic range, capture time and signal fidelity through techniques of oversampling, filtering, under-sampling, memory segmentation and triggering.