Towards Low Cost, High Speed Data Sampling Module for Multifunctional Real-Time UWB Radar

There is a need for the development of a low cost, low jitter, fast processing hardware for various ultrawideband (UWB) radar applications, such as dynamic real-time imaging and micro-Doppler human motion detection with high range resolution. Achieving such high range resolution is typically limited by the availability of low cost gigahertz sampling speed electronics. In order to achieve dynamic real-time imaging, a fast refresh rate and high-speed processing are essential, but they are typically very expensive and difficult to obtain. To circumvent the need for these very expensive processors, an equivalent time sampling method has been successfully applied to implement a compact data acquisition module with a low cost solution. The developed integrated compact module supports dual sampling channels with a maximal 100 giga-samples per second (GSPS) equivalent time sampling rate and relatively low jitter. The equivalent time sampling technique achieves a relatively high effective capture rate, however, this is at a cost of complicated timing control logic and sampled data reconstruction. The developed module includes a novel, robust, efficient, low-jitter data preprocessing scheme implemented in field-programmable gate arrays (FPGAs), and a faster back projection method based on look-up table for real-time 2D imaging. In the work presented here, the design details of the newly developed system as well as its performance are discussed. Various examples of utilizing the developed radar for real-time high resolution target imaging and micro-Doppler detection are also presented.