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Standoff Through the Wall Imaging Sensor User Evaluation, FCC Certification and Performance Improvement

NCJ Number
Date Published
March 2013
36 pages
This report explains the technology and describes the development of an ultra-wide band radar technology that has the capability to produce an imaging sensor that can both map the internal structure of a building and locate persons inside the structure.
The imaging system was developed by AKELA, Inc., and is called ASTIR (AKELA Standoff Through-the-Wall Imaging Radar). The underlying technology of ASTIR is multiple antenna, continuous wave, frequency stepping radar in a portable case that can be positioned at a standoff distance of up to 98 feet from the target building. Radar information is processed in real time on a laptop computer to allow detection and tracking of stationary or moving individuals within a building. AKELA leveraged radar technology being developed for military platforms, adapting it to fulfill the needs of law enforcement (LE), and at the same time, navigating the technical constraints and requirements particular to Federal Communications Commission (FCC) approved operation in an urban environment. Initially, a prototype system that operated between 500 Mhz and 2000 Mhz was tested both in the laboratory and on a challenging structure with 26.7 cm-thick double-reinforced concrete walls and metallic clutter objects located within the building. Both stationary and moving individuals were detected and tracked within the building. It has also been demonstrated that the use of multiple systems can provide significant situational awareness information to LE in resolving detected persons within groups and individuals concealed behind metallic barriers. In order to satisfy FCC constraints, the AKELA prototype radar was modified to operate in the 2900 Mhz to 3600 Mhz band. In addition, AKELA requested a waiver for LE operation in emergency operations in this band; waiver approval was received; however, final FCC certification is required prior to sale for LE application for field evaluation and operational deployment. 23 figures and 3 references

Date Published: March 1, 2013