Method of processing the sum and difference signals of a radar of the monopulse type for estimating the parasite phase introduced between these signals by the ultrahigh frequency formation circuits of the sum and difference channels

Claim 1

A method of processing the sum Σ and difference Δ signals, in azimuth: Σ a , Δ a and in elevation: Σ e , Δ e , of a radar of the monopulse type, for estimating the parasite phase Ψ introduced between these signals by the ultrahigh frequency formation circuits of the sum and difference channels, comprising: in calculating for each measurement made by the radar at least one case for the expressions S and D: first case: ##EQU14## for estimating the azimuth parasite phase Ψ a ; second case: ##EQU15## for estimating the elevational parasite phase Ψ e ; third case: ##EQU16## for estimating the differential parasite phase δΨ=Ψ a -Ψ e , respectively, (where the symbol * designates the complex conjugate quantity), it being understood that the radar wave emitted is polarized circularly and that the azimuth and elevation monopulse receivers receive respectively only one of the circular polarization types: right hand or left hand; in calculating the expression [S(k+1)-S(k-1)]D*(k) it being understood that the radar antenna sweeps during time in azimuth in the first case and in the second case, in elevation in the second case and that k-1, k, k+1 designate three successive times such that the difference S(k+1) (θ)-s.sub.(k-1) (θ) is of the same sign as d.sub.(k) (θ), where S.sub.(k+1) (θ) and s.sub.(k-1) (θ) respectively designate the gain of the sum channel at angle θ, in azimuth in the first case and in the third case, in elevation in the second case, respectively at times k+1 and k-1, and where d.sub.(k) (θ) designates the gain of the difference channel at angle θ and at time k, in the azimuth in the first and third cases, in elevation in the second case; in calculating the mean value of the result of the preceding expression for several successive times corresponding to several measurements successively made by the radar, which allows an expression of the form e j Ψ. a where Ψ is the parasite phase sought and "a" a real number of given absolute value and sign.

Claim 2

A method of processing the sum Σ and difference Δ signals, in azimuth: Σ a , Δ a and in elevation: Σ e , Δ e , of a radar of the monopulse type, for estimating the parasite phase Ψ introduced between these signals by the ultrahigh frequency formation circuits of the sum and difference channels, comprising: in calculating for each measurement made by the radar at least one case for the expressions S and D: first case: ##EQU14## for estimating the azimuth parasite phase Ψ a ; second case: ##EQU15## for estimating the elevational parasite phase Ψ e ; third case: ##EQU16## for estimating the differential parasite phase δΨ=Ψ a -Ψ e , respectively, (where the symbol * designates the complex conjugate quantity), it being understood that the radar wave emitted is polarized circularly and that the azimuth and elevation monopulse receivers receive respectively only one of the circular polarization types: right hand or left hand; in calculating the expression [S(k+1)-S(k-1)]D*(k) it being understood that the radar antenna sweeps during time in azimuth in the first case and in the second case, in elevation in the second case and that k-1, k, k+1 designate three successive times such that the difference S(k+1) (θ)-s.sub.(k-1) (θ) is of the same sign as d.sub.(k) (θ), where S.sub.(k+1) (θ) and s.sub.(k-1) (θ) respectively designate the gain of the sum channel at angle θ, in azimuth in the first case and in the third case, in elevation in the second case, respectively at times k+1 and k-1, and where d.sub.(k) (θ) designates the gain of the difference channel at angle θ and at time k, in the azimuth in the first and third cases, in elevation in the second case; in calculating the mean value of the result of the preceding expression for several successive times corresponding to several measurements successively made by the radar, which allows an expression of the form e j Ψ. a where Ψ is the parasite phase sought and "a" a real number of given absolute value and sign.