Coherent Ladar Angle Estimation Error Analysis

摘要

In this paper we developed the basic theory governing the performance of angle measurements in a quad-cell based coherent ladar. Performance was shown to depend on many factors. Key factors include the signal CNRs, the discriminator slope, which is maximized (β≈D/λ) for diffraction limited sensors, and the degree of power estimate correlation. The latter depends upon the CNR, target size and position, and BPLO configuration. It was shown that angle errors agree with first order models if the two bi-cell power estimates are uncorrelated but that the errors can be much smaller if they are highly correlated. A ladar signal simulator was developed to synthesize stochastic heterodyne signals. This signal simulator was used to corroborate the theory developed herein and as a source of synthetic signals for a ladar tracker simulator. The track simulator was used to demonstrate closed-loop angle/angle/range/Doppler tracking.