ATP-3-09-12 Field Artillery Counterfire and Weapons Locating Radar Operations Download
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AN/TPQ-36 Weapons Locating Radar Systems Characteristics and Employment 26 October 2021 ATP 3-09.12 J-7 Note. The AN/TPQ-36 requires a minimum of 50 mils of track volume to track a round for long enough to achieve a solution. Figure J-3. Vertical scan Note: Track volume is determined by the difference between vertical scan and the height of screening crest in mils. J-34. There are two other major factors that affect the AN/TPQ-36s ability to detect, verify, and locate. These factors are aspect angle and speed of the object. The aspect angle is the angle measured from antenna to the target path of the object. The aspect angle must be greater than 1600 mils. This means the object must be traveling toward the antenna. Objects approaching at 1600 mils may not be detected by the WLR. J-35. The velocity of the object is a critical element. The velocity must be within the minimum and maximum velocity thresholds for all WLR systems. AN/TPQ-36 VELOCITY REQUIREMENTS J-36. Most mortar, artillery, and rockets have a velocity greater than 80m per second. The velocity requirements for the AN/TPQ-36 are that it tracks objects moving toward the WLR at ground surface speeds of at least 50m per second and no greater than 1500m per second. Tracks objects moving away from the radar at ground surface speeds no greater than 80m per second. AN/TPQ-36 RADAR BEAMS J-37. A radar beam is actually composed of four individual beams that comprise a track cluster. The track cluster is simply identified as a radar beam. J-38. Figure J-4 shows a cross section of a radar track beam used to track an object traveling through the detection area.