In the summer of 2006, Phoenix police were looking for two serial criminals who were terrorizing the city. One criminal was suspected of up to 38 drive-by shootings, and the other was suspected of a series of sexual assaults and murders. As part of the investigation into the crime spree, Phoenix Police received emergency funding for a video surveillance system to cover a five-square-mile area.

Police turned to the Avrio Group, Salisbury , Md. The Avrio Group responded by deploying a system of 30 remote cameras with video transmission over a wireless mesh network. Using the city's fiber network, the video is backhauled to a central command center. The command center uses video management software from OnSSI , Suffern , N.Y. , to display the cameras on multiple, large plasma displays.

Detective Chris Jenson with the Phoenix Police Department is thrilled with the performance and mobility of the system. According to Jenson the system was deployed in less than three weeks and individual cameras and mesh nodes can be relocated as needed for other investigations.

This mobility was accomplished by deploying Avrio's self-contained Rapid Deployment Pole Cam system. The Pole Cam includes a network camera; Firetide radio node and power supply in a NEMA rated enclosure.

Mark Jules, President of Business Development, Avrio , said Phoenix joined a rapidly growing list of municipalities, airports and seaports that have deployed wireless video.

Why wireless?

The primary advantage of wireless outdoors is to avoid expensive and labor-intensive trenching, digging and cabling.

A wireless infrastructure can also extend the range of a data network. While Category 5 Ethernet is limited to lengths of 100 meters, traditional wireless mesh can extend to lengths greater than 500 meters between nodes.

Another advantage is mobility. Both cameras and the client workstations that receive the streamed video feeds have a degree of mobility.

Wireless Spectrum for Public Safety

Wireless networks are typically deployed using 802.11 (Wi-Fi) standards for radio transmission and reception. 802.11 works over the license-free 2.4GHz (802.11b/g) and 5.0GHz band (802.11a).

The unlicensed 2.4/5.0 GHz spectrum may not be well-suited for public safety applications like fire, police and emergency medical services. It can be congested by countless private and commercial Wi-Fi hotspots operating in the area.