A target tracking system and methods that can isolate and maintain stable track on a selected target in multiple-target environment. In multiple-target environments, the signal returns received at the sum and difference channels are composites of individual targets. By decomposing received signals into individual components, angle measurements to each target are computed, and consequently, a specified target is isolated and accurately tracked in a stable manner. The present invention provides for apparatus and methods that compute angle measurements to each individual airborne target in a multiple target environment. The composite return signals from a number of targets that are closely spaced in Doppler are decomposed into their individual components, and hence, tracking measurements to each target are obtained without interference from other targets. The present invention may be used to determine the angular position of individual airborne targets within a multiple target environment. The present invention exploits the phase relationship between the sum and difference channel outputs of a single Doppler filter and between the sum channel outputs of two adjacent Doppler filters to decompose composite signal returns of targets into their individual components. Consequently, an independent angle measurement for each target is obtained. In addition, the number of targets with distinct velocities may also be determined. Implementation of the present invention improves the performance of single target tracking in multiple-target environments. Since independent measurement to each target is obtained, accurate and stable track on any target is maintained.