Improved high-resolution direction-finding through use of homogeneous constraints

The authors present results that illustrate how incorporation of homogeneous linear constraints can improve the effectiveness of well-known high-resolution direction-finding methods. Results include: the demonstration that the resolution performance of MUSIC can be improved by incorporating suitable constraints; the use of constraints to clarify the relationship between the MUSIC and MinNorm algorithms, and to `explain´ the improved resolution threshold of MinNorm; and a procedure for constructing a reduced directional spectrum of minimum polynomial degree for common high-resolution techniques