Pulse radar apparatus

Claim 1

A pulse radar apparatus comprising: (a) a coherent transmitting and receiving unit including a transmitter and a transmitting antenna for the transmissison of radar pulses, a vertical array of N receiving antennas and N receivers connected thereto for the reception of echo signals and the processing thereof in each of the receivers into two orthogonally phase-detected and digitized video signal components i r and q r , where r=0, 1, 2, . . . , N-1; (b) a beamformer including N output channels (k) representing respective receiving beam patterns covering specific elevation intervals, where k=0, . . . , N-1, each output channel being adapted to derive from said components (i r and q r ) the orthogonal components (I k and Q k ) of a moving-target video signal P k originating from the respective receiving beam pattern; (c) a buffer and switching means electrically connected to the beamformer for selectively passing the orthogonal components (I k and Q k ) of each output channel of the beamformer; and (d) computing means electrically connected to the buffer and switching means; characterized in that: (1) the buffer and switching means is adapted to select two adjoining output channels (n and n+1) having orthogonal components (I n , Q n and I n+1 , Q n+1 ) of moving-target video signals P n and P n+1 with the maxium available amplitudes, and (2) the computing means comprises a pseudo-monopulse computing unit for determining from the selected components of P n , P n+1 the deviation in elevation Δα with respect to an elevation value α, which is the bisecting angle between the main beam directions α n and α n+1 of the receiving beam patterns n and n+1, by using the relationship: ##EQU12## where C is a constant.