Why go wireless?

With heightened internal security issues facing many organisations, your customers’ demands for cost-effective and reliable CCTV surveillance in and around their large sites, such as power generating plants have never been higher.

The need for remote surveillance and central control of large multi-site operations is increasingly important to ensure a rapid, co-ordinated response in the event of an incident. Viewing multiple ‘analogue’ cameras in a central security control room from around a sprawling complex or industrial plant requires vast amounts of cable and equipment. IP-Video has established itself as a reliable, high-quality cost-efficient alternative technology for CCTV surveillance, replacing multiple runs of video cable with a single Ethernet connection. But when IP-Video is combined with the latest wireless broadband technology it provides an unbeatable solution for remote site monitoring.

IP-Video basics

Live CCTV images are digitised and transmitted over a network using the TCP/IP protocol – the standard for most IT networks and the protocol used by the Internet. Transmitter/receiver units, such as the VideoBridge 6000 from IndigoVision, perform this conversion and plug straight onto the IP network (Fig 1). Alternatively IP-Cameras can be used that combine the conversion hardware with a professional colour camera. The digital images can then be converted back to analogue signals for display on monitors and recording in the normal manner.

Alternatively, simple to use software can allow the viewing, control and recording of the live digital images, from multiple cameras, directly from the network. Anyone with the right access rights can view and control these images from any point on the network, or via the Internet.

IndigoVision’s VideoBridge technology uses multi-cast video transmission, that allows any user to view any number of cameras from any point on the network without increasing the bandwidth requirements of the network.

Installation costs drop

The benefits of IP-video include:

• Significant reduction of cabling and installation l costs associated with wired systems
• Excellent live video quality
• Fully scaleable – additional cameras can be added anywhere on the network without additional cabling
• Software solutions for video recording and retrieval
• IP-Video systems can be implemented without degradation to the overall performance of the IT network – they can be easily retrofitted to existing computer networks
• Cameras can be viewed and controlled from any point on the network

The transmitter/receiver units also provide a full duplex audio channel and a serial interface for control of the camera PTZ functions.

The Wireless Connection

Many people have broadband connections to the Internet and wireless networks installed in their homes, all of which have been possible because of the advances in broadband IP wireless technology. This technology is now available in high-specification products that provide reliable, secure IP wireless connections for industrial and commercial applications. One such product is Motorola’s CanopyTM System, which in its simplest form mimics a CAT5 Ethernet cable wirelessly – allowing transparent interconnection of IP enabled products.

The Canopy platform operates in the unlicensed frequency spectrum and incorporates a powerful modulation scheme that improves the quality of data delivery and mitigates interference from other systems. A single point-to-multipoint system can cover a range of up to ten miles, while a point-to-point system can deliver up to 35 miles (Fig 2).

Wireless IP-Video in Action

An energy company wanted to update their security surveillance both within and around the perimeter of a power generating plant. As the majority of locations were long distances from the main generating building, a traditional wired coaxial video system was cost prohibitive and impractical to implement. The decision was made to use real time digital video interfaced to specialist analogue cameras, including high-specification infrared cameras (Fig 3).

IndigoVision VideoBridge 6000 units were used to convert the analogue video signals from the cameras to a digital IP stream. The 6000 units were then connected to a Motorola Canopy system that transmitted the IP data wirelessly back to the company’s IP network within the main generating building. The connection between each VideoBridge 6000 unit and the systems were made using Canopy Subscriber modules. These modules were installed on the camera utility poles and at a remote security control room. This provided a connection to the wireless IP network for the security team’s suite of computers and monitoring equipment.

This enabled monitoring and control of CCTV cameras locally, as well as the cameras at a site over 200 miles away via a secure Internet connection.

Clear line of sight

Canopy access points were mounted on the roof of the main power plant building, allowing a clear line-of-sight between the access points and the individual subscriber modules around the site. One subscriber module located behind a hill required the use of a ‘wireless repeater’ to extend the communications path back to the access point (Fig 4).

Each subscriber module was connected to an outdoor enclosure that contained an uninterruptible power supply, ensuring CCTV coverage even when the power is down, an Ethernet switch, a VideoBridge 6000 unit, a heater and a lightning surge suppressor. This provided a self-contained CCTV surveillance point that was immune to the environment and could be fully controlled by the remote security team without using any interconnecting cable.

• Mobilcomm is a systems integrator for wireless video and data applications (www.mobilcomm.com)
• Motorola is a provider of wireless, broadband and automotive communica-tions technologies and embedded electronic products (www.canopywireless.com)
• IndigoVision is a manufacturer of IP Video solutions for the security market (www.indigovision.com)