c a s e s t u d y : n u m b e r  t w o

Bluewater Shopping Complex

The Task

Having won the contract to provide an internal GSM system for One 2 One at the Bluewater Shopping Complex (some 17million sq ft of shopping malls) our client was not able to design a suitable fibre delivery system. With approximately 8 weeks to opening Lythgoes were approached for assistance and the existing design audited by our design team. From carrying out the audit and studying the existing site drawings it was obvious a site survey was required. A survey was undertaken, and sufficient data gathered to start some preliminary design work.

The survey revealed the difficulties in design being experienced by our client. Faced with only 5dB of power, the designers were struggling to keep connector losses within limits. It became apparent the system could not be designed economically using then available fibre termination equipment and an innovative approach to the installation was required.

The Solution

Calling on our experience and innovative abilities, we were able to design a system that not only

afforded total diversity and redundant capacity, but also a system that reduced splicing and connectorisation to a minimum. Working to a maximum power budget of only 3dB, the design proved to be a complete success. The only splices on the system are those to pigtails, and in view of the installation time available, the design also kept the number of cables installed to an absolute minimum, many antennas being served from each of 3 terminal points on the ring feeder cable.

The client had specified that armoured cable be used throughout, and in order to achieve the necessary bending radii, Pirelli were called upon to manufacture a bespoke cable having 12 fibres per tube, thus reducing the bending radii to suit the cable tray installation.

Suitable splice enclosures for the antenna locations were designed in house by Lythgoes, and a terminal wall box that would allow for ‘break-out’ splicing from the feeder cable of only those fibres requiring termination at that particular location was sourced.

Solutions now had to be found for delivering the armoured cable to the roof of the complex and for fleeting the cable along the cable trays.

Once all the information had been collated, the design was finalised and submitted to the client. The design was approved and Lythgoes were asked to submit a price for the installation work.

Working with KJR Cables, an acceptable quotation was approved and all materials ordered. A method statement and Health and Safety file was prepared and accepted at first submission by Bovis Lend Lease, the principal contractor for the site. Installation began 20 days before the complex was to be opened and work was completed on 3rd April, three days before the official opening.