Many fundamental issues for UWB ultra-high speed systems in 5G new spectrum and collision avoidance radar (CAR) which present and feature spectrum are still largely open. In this paper, distortion analysis of UWB multi-Gbps signals in multi-bands, from 1GHz to 90GHz, across microstrip technology, is investigated with one dimensional and two dimensional distributions in time and frequency domains. Some useful guidelines for selection of appropriate laminates in any 5G and CAR applications are extracted. The results of time, frequency and TFD show that there are many differences between propagation of commercial UWB short pulse and mm-wave modulated UWB short pulses across different laminates. Also, Wigner-Ville TFD shows many interesting information about this kind of signal. To verify these analyses, and considering other practical problems, like input transitions, an UWB multi-Gbps branch line coupler in 20-30GHz frequency bandwidth is designed, fabricated and analyzed using UWB Gaussian modulated signal. The experimental results of the fabricated hybrid show the average of -18dB of input matching and -20dB of isolation of isolated ports and the average of -4.6dB of coupling between input-output ports, including input-output transitions. Also, the experimental results show that this fabricated hybrid can handle a periodic Gaussian modulated signal up to 5Gbps which is a valuable result to use in many applications in 5G and CAR systems.

UWB, mm-wave, 5G, ultra short pulse, time frequency distribution, UWB coupler.