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PRF is crucial for systems and devices that measure distance. Radar; Laser range finder; Sonar; Different PRF allow systems to perform very different functions. A radar system uses a radio frequency electromagnetic signal reflected from a target to determine information about that target. PRF is required for radar operation. This is the rate at ...
A pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity.
When the PRF of the "jamming" radar is very similar to "our" radar, those apparent distances may be very slow-changing, just like real targets. By using stagger, a radar designer can force the "jamming" to jump around erratically in apparent range, inhibiting integration and reducing or even suppressing its impact on true target detection.
The first advantage the ASR-11 offers is the use of a low peak-power, solid state transmitter with pulse compression technology, replacing the ASR-9's high peak-power, short pulse power system. This gives the radar the ability to provide the same amount of energy to a target at long range while making the radar less sensitive at shorter ranges.
Each individual PRF has blind ranges, where the transmitter pulse occurs at the same time as the target reflection signal arrives back at the radar. Each individual PRF has blind velocities where the velocity of the aircraft will appear stationary. This causes scalloping, where the radar can be blind for some combinations of speed and distance.
Because of the low pulse repetition frequency (PRF) of most coherent pulsed radars, which maximizes the coverage in range, the amount of Doppler processing is limited. The Doppler processor can only process velocities up to ± 1 / 2 the PRF of the radar. This is not a problem for weather radars.
An ATC ground station consists of two radar systems and their associated support components. The most prominent component is the PSR. It is also referred to as skin paint radar because it shows not synthetic or alpha-numeric target symbols, but bright (or colored) blips or areas on the radar screen produced by the RF energy reflections from the target's "skin."
Scalloping happens in a two PRF detection scenario when target velocity produces a blind velocity for one PRF while the target is at the blind range of the other PRF. The blind velocity for a specific pulse repetition frequency (PRF) is an integer multiple of the following, which causes the signal to have zero doppler.