Factors affecting radar range resolution EECS 725 Introduction to Radar Presented by Susobhan Das

Outline…… Introduction Range Resolution Factors related to Range Resolution Theory of Range Resolution Development Dependency on relative RCS factor Dependency on Location Deviation Conclusion Reference

Introduction Range Resolution c : Speed of light in air /vacuum medium τ : Pulse width B : Bandwidth of the pulse = 1/τ

Factors related to Range Resolution Probability of resolving two targets Difference in RCS of the targets SNR of the system Separation between targets Range resolution depends on Bandwidth of pulse SNR of the system RCS of the targets Apparent target location ( deviation from the actual location)

σ k RCS of the k th target (k=1,2) R k Range location of the respective target r range variable Half Power bandwidth = c/2B Gaussian profile of the pulse-compressed return signal from a single point target Assuming random phase difference between two targets and distributed on [-π, +π] The envelop of the over all signal Local minimum at Deviation of peaks from the local minimum Theory of Range Resolution Development Continue…

: exact location of peaks : exact location of minimum

For local minimum Without loss of generality, assume Where α<1 Dependency on relative RCS factor

: deviation from the true location : maximum allowable deviation relative to the target range W -n nth branch Lambert W function Dependency on Location Deviation

Conclusion Common definition of Range Resolution modified with unequal strength of targets Existence of local minimum between two peaks and limiting deviation of peaks from true target location

Reference 1.Hasan S. Mir, and Blair D. Carlson, “On the Definition of Radar Range Resolution for Targets of Greatly Differing RCS” ieee transactions on instrumentation and measurement, vol. 61, no. 3, March P.-R. Wu, “A criterion for radar resolution enhancement with Burg algorithm,” IEEE Trans. Aerosp. Electron. Syst., vol. 31, no. 3, pp. 897–915,Jul H. S. Mir and J. D. Wilkinson, “Radar target resolution probability in a noise- limited environment,” IEEE Trans. Aerosp. Electron. Syst., vol. 44, no. 3, pp. 1234–1239, Jul