A good approximation of pulse compression degradation due to adaptive cancellation

An exact expression for the perturbed sidelobe level of a compressed pulse that has been preprocessed through an adaptive canceler was derived by the author (see ibid., vol.27, no.2, p.331-42, 1991). This exact expression requires computer assistance in order to be evaluated. A rule of thumb expression is derived which is a good approximation to the exact expression. This same approximation can be used to derive a good approximation for the canceler noise power level which is induced by having a desired signal present in the canceler weight calculation. An expression for the number of independent samples necessary to equalize the signal-induced power with the quiescent interference level is derived