The Changing Face of CCTV Design

Corporate acquisitions, IT convergence and systems integration have added new challenges to surveillance system infrastructure, so cabling and transmission options are evolving to stop system hubs from turning into disaster areas.

In a crisis situation, first responders can use wireless video infrastructures to send and receive live streaming video and mission-critical data simultaneously from their vehicles and in command centers. Wireless video infrastructures can also be used by corporations or educational facilities that may have deployed surveillance cameras at multiple sites throughout a city.

Wireless infrastructures work through receivers and transmitters that are mounted on buildings, water towers and other high structures to permit optimal communication between receivers and transmitters. Today, wireless infrastructures are capable of transmitting video surveillance images beyond 50 miles to recording and monitoring equipment.

There are two main types of wireless infrastructures.
• Point to point (PtP). This is a wireless infrastructure that uses only one transmitter and receiver. Point-to-point infrastructure is perfect for a single-camera scenario or a grouping of several cameras from a single location tied through a network.
• Point to multipoint (PtMP). Point to multipoint uses multiple transmitters and receivers. This type of infrastructure is perfect for large-scale video surveillance systems that have a deployment of cameras in multiple locations either mobile or stationary.

Fiber-optic Infrastructures
Fiber-optic video surveillance infrastructures are perfect solutions for camera installations that exceed the distance limitations of coaxial and UTP cabling. These systems use either multimode or single-mode fibers to transport video images and control data from cameras to recording and monitoring equipment. Fiber infrastructures use various multiplexing electronic devices to convert video and data signals into optical signals at the camera site or in wiring closets. The video and data signals are then reconverted back to either 75-ohm (traditional) or 100-ohm (digital/IP) signals in the security head end for connection to recording and monitoring equipment.

Long-haul fiber solutions are very popular with transportation departments. Many highway and tollway authorities use fiber solutions to monitor traffic through video cameras. These solutions are perfect for customers who have large LANs and WANs.

UTP Infrastructures
UTP infrastructures are beginning to emerge and become a major support infrastructure in the physical security industry. These infrastructures are ideal for supporting both legacy analog systems and digital/IP-based video surveillance technologies if properly designed to data transport standards.

There are many ways to use UTP infrastructures to support IP-based technologies.

Today, there is a small group of customers that use their current data network infrastructure to support IP cameras and various other IP-based technologies such as network monitoring equipment. Basically, the new IP-based devices act as any other node or workstation on your network. They fit right into an existing Ethernet network by simply plugging into an open port. Usually, a new horizontal run of cabling will need to be run so cameras can be placed high on a wall or in a ceiling. Such cameras should be powered locally.

Data networks can also be used to support existing analog technologies through the use of video baluns that convert 75-ohm analog video signals to 100-ohm video signals for distribution across an existing data network. The major drawback of putting IP cameras on an existing UTP network is the amount of bandwidth consumed by IP cameras. A parallel network is recommended to segment the bandwidth requirements of the video surveillance network from the data network.

Another type of UTP replacement technology being installed today replaces the coaxial cable with a pair of UTP cables. This reduces the installed cost but doesn't support Ethernet-based IP devices such as cameras or servers, which require high-performance four-pair UTP cables that meet industry standards such as TIA/EIA-568B.

Closed circuit twisted pair (CCTP), addresses the standard's requirements for data capabilities. CCTP, by Anixter, is a new method of transporting video, data and power signals over unshielded twisted pair (UTP). CCTP was designed to provide a video surveillance infrastructure that can address current technology cost effectively, while supporting migration to rapidly evolving IP-based surveillance systems.