Transformations providing for detection invariance with changes in the spectral parameters of low-frequency noise

It is proposed that preliminary transformation of signal and noise can be used to improve detection quality; the detection invariance is increased with respect to the parameters of low-frequency noise (e.g., deep underwater noise, and terrestrial electric and magnetic fields in the ULF range). The concept of the total invariance of a transformer is introduced. It is shown that the responses of a correlometer with Laguerre orthogonal filters and a correlometer with preliminary filtering by a CLR circuit differ by invariance with respect to LF noise. The invariance of these transformers is assessed along with the output SNR.