Most of the time, video surveillance systems use hardwired solutions to transmit video and control signals—copper or fiber for traditional CCTV or standard network infrastructure for networked, digital systems. However, it’s worthwhile to consider using wireless video transmission under certain circumstances.

• If a long distance separates the camera location from the control site. In this situation, trenching and cable installation may be cost prohibitive, right of way may be unavailable, and a leased line may incur too many recurring expenses.
• If your cable route is limited. In historical buildings it may be virtually impossible to provide an affordable and workable cable route.
• If you need a flexible deployment. For museums or exhibition halls, cameras must periodically be relocated to suit changing needs.
• If you require covert installation. Small, battery-operated, wireless covert units can be deployed quickly and easily.
• If you need a mobile solution. Mobile cameras can improve incident response by allowing the incident command center to monitor first-responder activities and provide accurate assessment of the situation.

Transmission Capacities and Security
Analog. Virtually all wireless video surveillance transceivers operate in the unlicensed part of the radio spectrum. Under the provisions of FCC regulations (47CFR parts 15 and 18), the industrial, scientific and medical (ISM) bands are a part of the unlicensed radio spectrum set aside for anybody to use without a license. One can easily find analog wireless video transceivers operating in the 5.8GHz, 2.4 GHz and 900 MHz ISM bands. There are a few wireless video devices operating in the 1.2 GHz amateur band, and some lower-power, short-range consumer products operating in the UHF band.

These analog video transceivers do not offer any special measures to secure the transmitted video signal. The full-frame, real-time NTSC video signal is sent via either FM or AM modulation, and the transmitted signal is received with the right receiver. Since these wireless video links operate in the unlicensed public access band, it is extremely easy and affordable for criminals to put together a wireless video receiver with an external antenna and a signal booster to intercept the unencrypted video signals.