In an FMCW radar system, the velocity of obstacles relative to the radar couples a Doppler frequency shift into the return signal which causes an error in the range measurement. It is known to use a radar signal having a frequency ramp that both increases and decreases to distinguish the range of an obstacle from its velocity but when multiple obstacles are present this is not practical. By using a measure of velocity from a succesion of return signals, which of the radar output signals from the...

A radar encoder comprising a delta modulation circuit which receives analog adar video data from a radar and then converts the data to digitized NRZL video data. The radar encoder also has an encoder circuit which receives the digitized NRZL video data as well as a trigger pulse signal and analog synchro signals from the radar. The synchro signals are provided to a Synchro-to-Digital Converter which converts the synchro signals to sixteen digital synchro data bits which are then latched into the...

A radar system having a transmitter for transmitting a series of radio frequency (RF) pulses with sequential, incrementally changing carrier frequencies. A receiver receives energy from multiple scattering points of an object reflecting such transmitted RF pulses. The received energy from each one of such scattering points includes a series of radio frequency (RF) pulses corresponding to the transmitted pulses delayed in time, .tau., from the transmitted pulses an amount proportional to the rang...

The invention relates to a radar apparatus (1, 2, 3) provided with a doppler filterbank (4) and fast thresholds (5.i), for writing per pulse a range-doppler matrix in range-doppler memory (6) and the background level in background memory (7). By unfolding the range-doppler matrices and combining the unfolded range-doppler matrices for all the pulses in a burst in combination means (10), an incoherent combination of the pulses is obtained before an actual detection takes place. This cluster befor...

In a transmission mode, one repetition transmission pulse generated by a transmitter is divided into a plurality of subpulses having different frequencies by a variable distributor. The subpulses are assigned to a plurality of elevation angle directions by phase shifters, and the assigned subpulses are transmitted from an antenna device. In a reception mode, the reflected signals of the subpulses transmitted in the range of the plurality of elevation or inclination angles are captured from this ...

A radar apparatus provided with a transmitting unit, antenna unit and a receiver unit. The transmitting unit transmits pulses having a modulation for enabling pulse compression on reception. As an ECCM feature, the radar apparatus is further provided with a blanking circuit. The blanking circuit includes two filters, one filter being responsive to the first half of the transmitting pulse only and the other filter being responsive to the second half of the transmitting pulse only. Blanking occurs...

There is provided a radar apparatus wherein a local signal having a coherent sine wave is modulated to generate a composite signal of two signals modulated by different modulation functions. The composite signal is transmitted as a transmission signal, and a reception signal associated with the transmitted signal is separated into two signal components modulated by the different modulation functions. A difference between the two signal components is found, thereby removing a reflection signal fr...

Radar apparatus provided with a transmit generator and antenna means for the transmission of comparatively long, linearly frequency-modulated transmitter pulses. Echo signals are received by antenna means and a heterodyne signal is generated in mixer stage. Propagation time differences for different echo pulses are compensated by means of a dispersive delay element incorporated in the radar receiver. Distortion of the echo pulses in the dispersive delay element is corrected on the basis of a Fre...

A radar reflector including a first and a second radar corner. The radar corners are formed by an essentially rectangular first flat plate and a second and a third essentially flat plate arranged perpendicular to the first plate at two perpendicular edges of the first plate and to meet the two edges of the first plate. The second and the third plates of the first radar corner are arranged to meet two different perpendicular edges of the first plate than the second and third plate of the second r...

Radar reflector structure is disclosed including a plurality of reflector elements which in use are arranged in a non-planar configuration, the reflector elements include a thin flexible member extending between adjacent reflector elements substantially at or below the surface of the elements, the thin flexible member thereby providing a flexible hinge between the elements.