Bistatic Altimeter Concept

The proposed Bistatic Altimeter concept is intended to provide a low cost solution to improve the accuracy of existing munitions such as the Joint Advanced Standoff Strike Missile (JASSM), Small Diameter Bomb (SDB), and the Joint Direct Attack Munitions(JDAM). For GPS guided munitions, the GPS navigation error can be related to the weapon CEP. Examining the unclassified ORD threshold for the current GPS capability, the horizontal accuracy is 6.3m but the vertical accuracy is 13.6m. It is clear thatvertical dilution of precision (VDOP) dominates the GDOP and can result in higher CEP than predicted. The concept exploits radiation from existing national or commercial assets as the transmitter and utilizes a new antenna, algorithms, processor, andreceiver to provide precise altitude measurements of the munition. Central to the research and critical to the ultimate success of the program and ultimate implementation, is a system configured for ease of integration into the weapon system. The antennaperformance in the installed configuration will be central to success and is an important aspect of the research. The technique also has application to manned aircraft; military, commercial, and private air transportation. Low cost precision guidanceand low cost precise altimetry of munitions and aircraft. The technology will find many application in precise navigation and mapping and radar ranging.