Patent ID: 8269665

Claim:
A radar system, comprising: a beam direction controller: a transmitter for transmitting subpulses at nominal frequencies F with modulation which is capable of resulting in an actual average frequency different from frequencies F; a monopulse receiver for receiving signals from a target, and for generating rho (ρ) signals, each of which rho signals is a real component of one of eight complex monopulse ratios, four of which represent a Δα angle and the other four of which represent a Δβ angle; a polynomial processor coupled to said receiver, for producing uncorrected cosine differences of angular offsets of a target from a commanded beam pointing direction or angle cosines cos(α 0 +δα)−cos α 0 cos(β 0 +δβ)−cos β 0 ; a multiplicative correction processor for multiplying said uncorrected cosine differences by a factor including (a) a frequency at which a polynomial is determined and (b) an actual average frequency of a particular subpulse, to thereby generate multiplied cosine differences for each subpulse; a summing correction processor coupled to said multiplicative correction processor for adding to said multiplied cosine differences a correction term for compensating for apparent movement of the target arising in a particular direction from beam movement at each subpulse, to thereby generate a plurality of multiplicatively and additively compensated angles or angle cosine difference signals; and an averaging arrangement coupled to said summing correction processor for averaging said angles or angle cosine difference signals over all subpulses of a pulse to thereby produce averaged angular difference signals representative of a location of the target, wherein ρ=a real component of one of eight complex monopulse ratios; Δα=difference of half-antenna outputs corresponding to an α direction; Δβ=difference of half-antenna outputs corresponding to a β direction; α 0 =direction angle measured from a positive X axis to a beam direction line; β 0 =direction anile measured from a positive Z axis to the beam direction line; δα=departure angle from beam direction angle α 0 ; and δβ=departure angle from beam direction angle β 0 .