Introduction

Tyco Integrated Systems have implemented a video surveillance system on the M6, M42 and M5 motorways around Birmingham, known as the Birmingham Digital Ring. The system links Motorway transmission stations at Ray Hall, Bromsgrove, Umberslade and Coleshill with the Police Control Office at Perry Barr. Thus providing a mechanism for delivering a complete real time view of the traffic flow around the West Midlands utilising uncompressed high quality video transmission technology. This method of transmission is an efficient, cost effective way of connection and control across a surveillance network.
 

Features

• Each transmission station on the ring is linked to the PCO
• Each transmission station has matrices to switch cameras onto the digital ring or pictures off to engineer’s positions or cross-boundary connections
• Digital video recording is provided for each camera
• 2 bi-directional channels provide redundancy for switching pictures
• 10 Ethernet connections around the ring provide a fast reliable communications medium for retrieving DVR data
• Two transmission stations are equipped with an engineers position to allow maintenance to take place
• A Video Routing Manager operates at the control office to switch both the video matrices and backbone transmission circuits

 Currently more than 280 cameras are installed around the Birmingham Digital Ring. The system provides for future expansion and has the capacity to cope with more than 700 inputs. From each camera site along the motorway, fibre transmission equipment carries the picture to the nearest transmission station on the digital ring. At each transmission station the local cameras are presented to a video matrix and a number of digital video recorders (DVR’s).  These are used to record all of the cameras which feed into the local transmission station matrix. 

A video routing manager at Perry Barr provides control of both the matrices and digital transmission backbone. Data channels are carried in opposite directions around the ring so that if a fibre breaks, there will be an alternative route for selection of video.

The digital backbone comprises of a series of sophisticated, state of the art transmission hubs equipped with video input and output cards and a number of data cards. There are a total of 8 hubs used for the digital ring, 4 hubs which transmit in the clockwise direction and 4 hubs which transmit in the anti-clockwise direction. This provides a total of 80 video channels, 40 data circuits and 10 Ethernet circuits around the digital ring providing a fast and comprehensive coverage, 24 hours a day, 365 days a year.

The data circuits are used for a number of different purposes including the control of the fibre chassis themselves, matrix control, anemometer data, control panel hi-ways (for the engineer’s positions), V26 audio (camera control) and cross-boundary data (TV Network Protocol).

Customer Benefits

A key benefit is; if a fibre is unavailable, the system will allow the selection of video signals via an alternative route. A fault reporting system advises the maintenance engineer of the problem.

The transmission stations at Coleshill and Ray Hall are each equipped with an engineer’s position to allow maintenance functions to be carried out. Each engineer’s position is equipped with a control panel and a video monitor, to which any camera can be routed to make fault finding quicker and easier. 

This system has the flexibility to not only be installed on motorways but also in a variety of environments, within many surveillance applications.