A digital down conversion of WB radar based on intersection of spectrum

A new wideband digital down conversion (WB-DDC) method based on intersection of frequency spectrum is proposed. In this method, the input wideband signal is split into several subbands by analysis filter bank and each of these subbands with explicit meanings can be processed independently. The outputs of useful subbands are combined by synthesis filter bank to get the complex baseband signal. That means subband operation becomes possible and great flexible comparing with the traditional structure. Moreover, the new method is computationally more efficient than the traditional method. The methods of designing filter bank and the perfect reconstruction condition are analyzed. The influence of the prototype filter to reconstruction is indicated by simulation. The simulation results show that the presented method is of good performance.