Imagine pursuing a suspected purse snatcher at a downtown political rally - you know he's out there somewhere, but where do you look? Fortunately, digital video technology has now progressed to the level that first responders are able to view and track suspects, even when buildings, walls, people and other barriers stand in the way.
This is made possible through the use of next-generation digital 
transmitters and handheld video receiver technology. The first digital video transmission system to the market, and still one of the most popular, is the Coded Orthogonal Frequency Division Multiplex (COFDM) technology implemented by Pacific Microwave Research, Inc (PMR) of Vista, California. COFDM is engineered to be used in urban and other high "noise" environments, created when signal transmissions (called "signal reflections") bounce off buildings, walls and other barriers.
PMR was formed in 1999 when its founders, Chris Durso and Dave Dirdo, set out to address problems with video transmission in the urban environment. The pair saw the need for video transmission products to be used by law enforcement for convert surveillance activities.
Video signal transmissions in urban environments had long been a problem for law enforcement and security personnel attempting to establish video surveillance for crowd control, suspect pursuit and criminal stake outs. The problem arises when the reflected signals bounce off buildings and other barriers, causing the receiver to pick up multiple transmissions. Adding to the confusion is the fact that the reflections are time delayed and can cancel out a direct signal, resulting in loss of the video image.
In 2001, Durso and Dirdo designed a system that operated in an urban or airborne setting that could benefit from the reflected signal interference with very little lag time. Unlike most wireless video transmission equipment, PMR's system using COFDM technology (now called the Tactical Video System) works best where there is plenty of signal reflection.
The San Diego Police Department (SDPD) had previously used PMR's equipment for a Fourth of July celebration in 2002. They were so impressed, that they turned to PMR again to help with crowd control during Super Bowl XXXVII in January 2003. The company lent the department three of their handheld receivers and a briefcase-sized receiver for use in the highly reflective downtown area. The operation was a success and shortly after the game, PMR received a letter from then-San Diego police chief, David Bejarano, personally thanking the company for their assistance during the event.
Shortly after the Super Bowl, PMR management went online to search for funding opportunities. Durso located the Center for Commercialization of Advanced Technology (CCAT) in April 2003 through the Regional Technology Alliance (now part of CONNECT).
The company was initially awarded a market study, but CCAT hadn't forgotten Durso's request for funding. Upon completion of the market study, the CCAT management team reviewed PMR's original application and was impressed enough to offer PMR $75,000 to develop the prototype of a small hands-free transmitter that could be worn on the body (now called the DT-200 Series).
In 2005, PMR tuned to CCAT again, this time to finance the next component of the Tactical Video System which was the prototype for a corresponding video receiver. The plan called for the ruggedized receivers to be used in emergency vehicles, robotic applications, portable tactical command centers and observation posts. CCAT awarded another $75,000 to develop the receiver within weeks of receiving PMR's Follow-On application.
The company's association with CCAT has offered PMR more than money - "There's a cachet to CCAT," said Durso. Durso continued to say that CCAT's contacts and influence had opened opportunities to the company that had been hard to get prior to his CCAT affiliation.
Defense contractors General Dynamics, Lockheed Martin and Northrup Grumman are using PMR's equipment for payloads on unmanned ground and aerial vehicles (robots and UAVs) engineered to perform digital video surveillance in Iraq, Afghanistan and other areas with military presence. PMR has signed other contracts submitted by federal law enforcement agencies that have requested confidentiality in order not to expose their surveillance methods.
In 2006, the SDPD has outfitted four departmental helicopters with PMR surveillance equipment. This equipment will provide officers on the ground with aerial views of dynamic situations such as large concerts, sporting events, unfolding criminal activity and other situations that require monitoring or crowd control.
For more information, please contact:
Tom Sheffer, CCAT Program Director
SDSU Research Foundation
E-mail: tsheffer@foundation.sdsu.edu
Phone: (619) 594-4135 / Fax: (619) 594-5774