Cascade array structures

The complexity of calculating the weights for an adaptive antenna array is reduced. The advantages of cascaded adaptive arrays are discussed. General formulas for the cascade optimum cascade weights, SINR (signal-to-interference-noise ratio), and gain are developed. These formulas are applied to a five-element array treated as two-, three-, and four-element subarrays. The following are advantages of a cascade approach: (1) processor complexity is lowered, and a time-division-multiplexed (TDM) processor is possible; (2) only one subarray needs to be adapted per stage; and (3) the number of inputs in each subarray is limited, and therefore higher complexity algorithms are possible