ATP-3-09-02 Field Artillery Survey Download
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Global Positioning System Application and Systems 16 February 2016 ATP 3-09.02 9-9 Humidity range. 0 to 100 percent. Display heater. When enabled, turns on at -20 °C. ALTITUDE 9-30. DAGR altitude ranges: Operating altitude range. -400 to +9,100 meters (-1312 to +29,848 feet) mean sea level (maximum rate of change for operation is -100 meters [328 feet] per second). Storage altitude range. -400 to +15,000 meters (-1312 to +49, 200 feet). DUST AND WATER 9-31. The DAGR is sealed against dust and water to a depth of 1 meter (3 feet) for 20 minutes. ELECTRONIC WARFARE 9-32. When loaded with crypto keys, the DAGR provides accurate PVT in a spoofing environment; including fast direct-Y acquisition and area navigation functions. No operator action is necessary to initiate anti-jamming. SPOOFING AND ANTI-SPOOFING CAUTION To enable DAGR operation during spoofing, the receiver must be loaded with current crypto keys. L-band radio transmissions may interfere with DAGR operations. 9-33. Hostile parties may attempt to imitate (spoof) GPS satellite signals to cause errors in navigation and position information. The DAGR employs crypto keys to protect against these attempts. Other than loading crypto keys, no other operator action is necessary to initiate anti-spoofing. Some signals generated by the satellites are encrypted to deny certain users the reception of those signals. This is called antispoofing (A- S). Entering crypto keys allows the DAGR to receive those signals, when available. A selective availability antispoofing module (SAASM) is used for advanced security as well as code types course/acquisition (C/A), precise (P), and encrypted Y code. When operating the DAGR in a secure environment, valid crypto keys are loaded into the receiver for protection from intentionally degraded (spoofing) satellite signals. To improve operation when spoofing occurs, ensure current crypto keys are loaded. CAUTION Accidental jamming may occur when operating the DAGR near a tank, dense foliage, or a source of high power electronic emissions. Move away from these sources and verify operation. DETECTION OF JAMMING 9-34. The DAGR provides multiple methods of detecting jamming as follows: Jammer finder page of the application submenu—The L1 and L2 frequencies are monitored for signal jamming noise. The direction of the jamming signal is determined by signal strength. The signal azimuth and the DAGR present position are stored as an EW waypoint. Multiple EW waypoints are used to calculate the jammer signal source position. Channel status page of the satellite submenu—Individual satellite data for active channels is viewed using the channel status page of the satellite submenu. The J/I (jamming or interference)