Abstract: A system for manned or unmanned flying bodies detects covered or hidden targets on the ground by using relatively "longwave" radar radiation for immediately attacking such ground targets, which may be covered by trees for example, but located on a strip of ground extending with a given width below the flight path of the flying body travelling in low altitude flight. Four radar receiver antennas are equally spaced from each other along the wings of the flying body and one transmitter antenna is located between two pairs of receiver antennas. The receiver signals are submitted by a fast Fourier transformation for providing a wavefront reconstruction. The so transformed, received signals are then evaluated in accordance with the known SAR principle directly as the signals are received and transformed by correlation with expected signal functions, so-called reference function, for producing a control signal for the direct or indirect discharge of a weapon.

Abstract: In a method and an apparatus for radar surveillance a multilobe antenna is commonly used for transmission as well as reception and distributes the power (P) to be radiated in several (n) simultaneous and uniform radiation lobes (L1-L7 ) which are swept across a zone to be surveyed.The antenna properties are maintained invariant while each signal transmitted or received by the antenna is coded by allocating a particular code element ({e.sub.i }.sub.1.sup.n) to each lobe (L1-L7 ). Each code element ({e.sub.i }.sub.1.sup.n) is fixed for forming, when the lobes (L1-L7) sweep, the received signals into a reception sequence ({S.sub.R .nu.)}.sub.1.sup.n) of elements ({.sigma..sub.o c.sub..nu. }.sub.1.sup.n) having predetermined mutual relations. The reception sequence is correlated by means of a correlation sequence of elements ({c.sub..nu..sup.* }.sub.1.sup.n) which are proportional to the conjugated elements of the reception sequence.

Abstract: A target track data correlating decision in a multisensor system which decides whether the tracking data and observation data sent from a plurality of sensor sites are ones on the same target or different targets on the basis of the data. The correlation decision is implemented in a method and apparatus in such a manner that the likelihood ratios of parameters of the target track data are calculated and compared to decide whether the target is the same or not in accordance with a density distribution of each parameter of the data.

Abstract: In side-lobe cancelling equipment direct jammer signals appearing in an auxiliary antenna channel are better correlated with reflected jammer signals in a main antenna channel by splitting the signal in the auxiliary channel into two parts, one of which is directly correlated with direct jammer signals in the main channel and the other is passed through a delay line to alter its timing to match the timing of the reflected jammer signals in the main channel.

Abstract: A radar correcting system has features for providing a corrected radar receiver reflection to a Doppler process unit. The corrected receiver pulse accounts for variances in phase, amplitude and frequency of the transmit pulses. The system has a phase detector that detects the phase difference between a stable oscillator and the transmit signal, providing a complex video or real and imaginary outputs. An operator that will normalize the transmit pulse is determined. The operator is applied to the reflections received by the receiver antenna to remove from the reflections any vagaries due to varieties in the transmit pulses. The data proceeding to the processor deals only with the objects causing the radar reflection.

Abstract: A pulse radar apparatus is provided with a first receiver (4) connected to a directional antenna (3) and a second receiver (13) connected to an omnidirectional antenna (12). The receivers (4, 13) are suitable for reception and processing of long-duration and short-duration radar signals respectively, whereby at least the long-duration signals are frequency-modulated and subjected to pulse compression. The radar apparatus is further provided with a side-lobe blanking circuit (20) and switching means (25, 26).