Prediction of Adaptive Array Performance

A direct relationship between the conventional properties of an array and the array performance in an adaptive mode is given. Expressions are provided to obtain the output signal-to-interference-plus-noise ratio (SINR) of an adaptive array in terms of its conventinal pattern and the locations of the desired signal and jammers. These expressions permit one to evaluate the performance of an adaptive array without an exhaustive search for all possible scenarios and parametric values to ascertain that the required performance levels be met. In fact, one can predict the jammer locations for which the array will provide its best and worst performance by observing the conventional pattern. Several examples are provided to demonstrate the relationship between the conventional pattern and the adaptive array performance. The examples include both linear and planar arrays.     

A Decision Theoretic Approach to the Angular Resolution and Parameter Estimation Problem for Multiple Targets

The problem of multiple-target resolution and parameter estimation is formulated in a decision theoretic context. The estimation portion of the problem is explicitly solved and experimentally implemented. The results show that it is possible to obtain accurate parameter estimates for targets separated as close as a quarter of a 3-dB beamwidth. This resolution was obtained for reasonable SNR's and with a system that utilized only commercially available components.     

Optimum Frequencies for Aircraft Classification

The selection of the optimum features for aircraft classification from radar returns was studied. A constraint was imposed that a minimum number of simultaneous frequencies be used. The results indicate that a high reliability of classification is achievable with only two frequencies, and even a single frequency can provide over 95 percent reliability if both phase and amplitude at two orthogonal polarizations are used. The data set tested involved eight military aircraft whose sizes varied over a three-to-one range.