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Through-the-Wall Sensors (TTWS) for Law Enforcement: Test & Evaluation (Version 1.2)

NCJ Number
Date Published
March 2014
123 pages
This report presents the procedures and results of the testing and evaluation of commercially available through-the-wall sensors (TTWS) conducted by the National Institute of Justice (NIJ) Sensors and Surveillance Center of Excellence, along with a NIJ-sponsored TTWS prototype with standoff (SO) detection capabilities.
The four devices tested and evaluated on performance and usability were the Range-R by L-3 Communications; Xaver 100 by Camero-Tech Ltd.; Xaver 400 by Camero-Tech Ltd.; and the AKELA Standoff Through-wall Imaging Radar (ASTR) by AKELA (NIJ prototype). Overall, each device displayed strengths and weaknesses in different areas of evaluation. The Range-R and the Xaver 100 were the smallest and easiest to handle during storage, transport, and use. During "Against the Wall" (ATW) testing, in which the tested device was placed directly against a barrier, the Xaver 400 was superior at target detection; and the ASTR (NIJ prototype) was superior when setting up the device at a distance from the barrier (SO); however, the ASTIR was the only SO device tested. There were six key observations. First, larger devices tend to have more antennas and better signal processing capabilities, which improve detecting and locating targets. Second, smaller devices are more easily stored, transported, and used with a minimum of encumbrance to the operator. Third, the Xaver 400 had the best overall percent detection of the ATW devices; but is the largest and heaviest of the ATW devices; the Range-R and the Xaver 100 are more easily stored, transported, and handled. Fourth, the ASTIR is a prototype device and is the largest and most encumbering of the devices tested. Each device has strengths and weaknesses between detection, operation, and supporting activities, such as repositioning the device at the scene. Testing was done using seven different types of barrier (wall) materials. 68 tables, 50 figures, and 10 references

Date Published: March 1, 2014