tailieunhanh - RADAR MODES

Typical Radar modes are listed below in the general functional category for which they were designed. Not all of these modes are applicable to all radars and certain radars have additional modes. | RADAR MODES Typical Radar modes are listed below in the general functional category for which they were designed. Not all of these modes are applicable to all radars and certain radars have additional modes. NAVIGATION Terrain avoidance - A mode in which the radar is set at a fixed depression angle and short range to continuously sweep the ground area directly in front of the aircraft in order to avoid mountains. This is particularly useful during flight into unfamiliar territory when clouds haze or darkness obscure visibility. Ground mapping - A mode in which the radar uses a variety of techniques to enhance ground features such as rivers mountains and roads. The mode is unlike air-to-air modes where ground return is rejected from the display. Precision velocity update Doppler navigation - A mode in which the radar again tracks ground features using Doppler techniques in order to precisely predict aircraft ground speed and direction of motion. Wind influences are taken into account such that the radar can also be used to update the aircraft inertial navigation system. FIGHTER MISSIONS Pulse search - Traditional pulse techniques are used to accurately determine range angle and speed of the target. Limitations are easy deception by enemy jamming and less range when compared to other modes. Velocity search - A high PRF Pulse Doppler waveform is used for long range detection primarily against nose aspect targets giving velocity and azimuth information. Although velocity search can work against tail-on targets the Doppler return is weaker consequently the maximum detection range is also much less. When the target is in the beam flying perpendicular to the fighter the closure Doppler is the same as ground return and target return is almost zero. Track While Scan TWS - A system that maintains an actual track on several aircraft while still searching for others. Since the radar is sharing it s computing time between targets the accuracy is less precise than for a single .