Modified Microwave Sampling Beamformer for Fast Weighting Control and Image Rejection

A modified microwave sampling beamformer (MSBF) for fast weight control and image replica rejection is presented. In the MSBF, each element weight is modified by controlling the corresponding switch using a pulse train with adjusted pulse width and time delay. A new limit for the sampling frequency is obtained as a function of the signal bandwidth and the pulse train duration. The image replica is introduced and techniques to lower its effect or to reject it are proposed. The relation between the sampling frequency and the pulse train duration, the effect of the image replica, and the effectiveness of the rejection technique are verified by simulating the new structure in the time domain.