CW Doppler Radar Block Diagram: A simple CW Doppler Radar Block Diagram, such as the one shown in Figure 16-14, sends out continuous sine waves rather than pulses. It uses the Doppler effect to detect the frequency change caused by a moving target and displays this as a relative velocity. Since transmission here is continuous, …
Phased Array Radars: Phased Array Radars – Introduction With some notable exceptions, the vast majority of radars have to cover an area in searching and/or tracking, rather than always being pointed in the same direction. This implies that the antenna will have to move some limited beam movement can be produced by multiple feeds or …
Frequency Modulated Continuous Wave Radar: The greatest limitation of Doppler radar, i.e., its inability to measure range, may be overcome if the transmitted carrier is Frequency Modulated Continuous Wave Radar. If this is done, it should be possible to eliminate the main difficulty with CW radar in this respect, namely, its inability to distinguish one …
Radar Beacons: A Radar Beacons is a small radar set consisting of a receiver, a separate transmitter and an antenna which is often omnidirectional. When another radar transmits a coded set of pulses at the beacon, i.e., interrogates it, the beacon responds by sending back its specific pulse code. The pulses from the beacon, or …
Moving Target Indicator Radar Block Diagram: Basically, the Moving Target Indicator Radar Block Diagram compares a set of received echoes with those received during the previous sweep. Those echoes whose phase has remained constant are then cancelled out. This applies to echoes due to stationary objects, but those due to moving targets do show a …
Doppler Effect in Radar: The apparent frequency of electromagnetic or sound waves depends on the relative radial motion of the source and the observer. If source and observer are moving away from each other, the apparent frequency will decrease, while if they are moving toward each other, the apparent frequency will increase. This was postulated …
Pulsed Radar Systems: A Pulsed Radar Systems is generally required to perform one of two tasks: It must either search for targets or else track them once they have been acquired. Sometimes the same radar performs both functions, whereas in other installations separate radars are used. Within each broad group, further subdivisions are possible, depending …
Display Methods in Radar System: The output of a radar receiver may be displayed in any of a number of ways, the following three being the most common Display Methods in Radar System are: Deflection Modulation of a cathode-ray-tube screen as in the A scope, Intensity Modulation of a CRT as in the Plan-Position Indicator (PPI) …
Antenna Tracking System: Having acquired a target through a scanning method as just described, it may then be necessary to locate it very accurately, perhaps in order to bring weapons to bear upon it. Having an antenna with a narrow, pencil-shaped beam helps in this regard, but the accuracy of even this type of Antenna …
Antenna Scanning Methods: Radar antennas are often made to scan a given area of the surrounding space, but the actual scanning pattern depends on the application. Figure 16-6 shows some typical Antenna Scanning Methods. The first of these is the simplest but has the disadvantage of scanning in the horizontal plane only. However, there are …