TRANSMISSION

Although there are some limitations to its usage, microwave technology has certainly broadened the scope of security installations. According to Keith Simpson, president and chief executive officer at Simpson Security Systems, an increasing number of jobs they are handling involve microwaves to move both data and video signals, including those from pan-tilt-zoom cameras. The key limitation with microwaves, said Simpson, is the need for line of sight between transmitters. As a result, equipment is often mounted on towers, which can be up to several hundred feet tall. Microwaves are primarily used as an open-area solution, he said, or when transmitting video among multiple sites. In addition, said Simpson, the microwave transmitter is not contained in the camera, which allows the use of analog cameras or digital ones with analog or digital transmitters as well as the addition of an illuminator. “You can go up to 20 miles, depending on the line of sight,” explained Simpson. Although the cost is still higher than a typical surveillance camera set up - about double, he said - it’s still cheaper than trenching cable, which can be prohibitive and maybe even impossible given the setting. Another consideration with microwaves is ensuring that the frequencies used won’t interfere with other frequencies in use. Proximity to airports and hospitals requires special licensing, he added. Still, Simpson said microwave usage for security purposes has been on the upswing since he began doing these types of installations five years ago. Customers with existing surveillance systems can add this technology, he said, as well as having it work for new installations. Simpson said his learning curve has dealt primarily with obtaining the proper line of sight between towers. Lasers are now employed to determine this, he said. Because of its increased use, Simpson said he expects manufacturers will continue to look for ways to improve systems, bringing all the components together in a single unit.