Patent Number: 6,310,575

Title: Method for the detection especially of small sea targets

Abstract: A method for the detection of a target by a radar in the presence of noise, the detection being performed on M antenna rotations, comprises at least: a first step for the estimation of the Doppler frequency (f) of the target; a detection step, the target being detected if an associated variable Z is greater than or equal to a predetermined threshold S, the variable Z being defined according to the following relationship: ##EQU1## D.sub.t being the time domain [-t.sub.0, t.sub.0 ], t.sub.0 being fixed as a function of the possible errors of framing of the signals from rotation to rotation; D being the frequency domain .left brkt-bot.f.sub.d -f.sub.0, f.sub.d +f.sub.0.right brkt-bot., f.sub.0 fixed as a function of the possible errors of estimation of the Doppler frequency; z being the signal at the analyzed antenna rotation referenced "0", at the analyzed range gate references "0"; z.sub.i.sup.k being the signal obtained by tracking at the rotation i of the signal z, in taking account of the tracking error in any, i.e., offset by k range gates with respect to the estimated range gate; C.sub.z,.sub.z.sub..sub.f .sub..sup.k (t,f,G)being the Cohen transform of the signals z and z.sub.i.sup.k with a kernel G, computed at the time t and the frequency f; C.sub.z.sub..sub.i .sub..sup.k, .sub.z.sub..sub.j .sub..sup.l (t,f,G) being the Cohen transform of the signals z.sub.i.sup.k and z.sub.j.sup.l of the kernel G, computed at the time t and at the frequency f; 2N.sub.d +1 being the number of range gates taken into account, according to the tracking error if any; N(i, k, j, 1) being a standardization.

Inventors: Chabah; Myriam (Brest, FR), Marchalot; Gabriel (Brest, FR), Quellec; Jean-Michel (Ploumoguer, FR)

Assignee: Thomson-CSF

International Classification: G01S 7/292 (20060101); G01S 13/00 (20060101); G01S 13/524 (20060101); G01S 013/52 ()

Expiration Date: 10/30/2018