  Standard noise radars, as well as noise-type radars such as quantum two-mode
squeezing radar, are characterized by a covariance matrix with a very specific
structure. This matrix has four independent parameters: the amplitude of the
received signal, the amplitude of the internal signal used for matched
filtering, the correlation between the two signals, and the relative phase
between them. In this paper, we derive estimators for these four parameters
using two techniques. The first is based on minimizing the Frobenius norm
between the structured covariance matrix and the sample covariance matrix; the
second is maximum likelihood parameter estimation. The two techniques yield the
same estimators. We then give probability density functions (PDFs) for all four
estimators. Because some of these PDFs are quite complicated, we also provide
approximate PDFs. Finally, we apply our results to the problem of target
detection and derive expressions for the receiver operating characteristic
curves of two different noise radar detectors.
