A method of bandwidth widening using multi direct digital synthesizer for SAR

Resolution of synthetic aperture radar is divided into two-dimensional space: Azimuth and range resolution. The range resolution is determined by the bandwidth of signal. Conventional synthetic aperture radar system uses multiplier to expand the bandwidth, however, the distortion in spectrum also are expanded. In this paper, the method for bandwidth widening using multi direct digital synthesizer blocks is designed and compared. We formulate signal parameters to widen bandwidth without multiplier. In addition, we confirm the wide bandwidth while maintaining minimal system clock. However, the number of blocks is not proportional to the signal quality. We derive the optimal number of blocks considering by the cost effectiveness and the signal quality.