Beam Pattern Design in Phased MIMO Radars for Known Target Locations

Multiple Input Multiple Output (MIMO) radars are the new generation of array radars that employ orthogonal waveforms as their probing signals. Despite several advantages, this strategy results in losing coherent processing gain. Many efforts have been made to overcome this weak point by modifying the correlation of transmit signals. Recently, a new phased MIMO radar has been proposed that partitions the transmitting array into a number of sub arrays, and allocates a waveform to each of them that is orthogonal to the waveforms transmitted by other sub arrays. In this radar, designing the weight vectors of each sub array provides a means of forming the desired beam pattern. This paper proposes a method for selecting weights based on conventional beam forming to maximize power around targets of interest and considers the results of this signal design on the receiving end by implementing four parameter estimation algorithms. Unlike the method used for MIMO radars, in this procedure both transmitted power from antennas and distribution of power among targets can be controlled and the desired beam pattern is obtained with less calculation and less orthogonal waveforms. The method is also extended to the planner array.