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Looking Through Walls

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Date Published
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This document presents the specifications of a radar-based, through-the-wall surveillance system known as MARS (Motion and Ranging Sensor).


Through-the-wall surveillance enables law enforcement officers to determine the location of armed suspects and the number of potential adversaries in a building, as well as assess conditions for offensive operations. It can also support search-and-rescue operations in hostage situations and disasters. As one example of such surveillance, MARS' radar, which is capable of penetrating concrete and masonry, is an improved version of an earlier technology. MARS combines an enhanced two-dimensional, concrete-penetrating radar technology with three-dimensional imaging radar that can penetrate interior walls and map both fixed and moving objects. The two-dimensional technology detects movement while the three-dimensional imaging portrays depth or range. The MARS operator can display many different views of a scene on the computer screen, including a "birds-eye" view looking down on the scene, a side view that portrays the height of objects, and a three-dimensional image that maps objects from any point in the scene. Fifty modes of data display can enhance each of the basic display modes. Plans are underway to complement the custom software with commercially available software, so as to develop more readable displays. The sensor will also include data processing that can analyze motion, displaying only the radar returns that represent likely human movement. The improved MARS will weigh less than 35 pounds and fit into a briefcase. The user can set up the sensor and then move to another location for safety or a hidden surveillance.

Date Published: January 1, 2000