Figure 3.1 shows a number of base stations (three in this figure) that are deployed every several km that provide ‘coverage’ over a full service area such as a city. To provide coverage an initial theoretical design is shown in Figure 3.2 where the coverage is provided by adjacent hexagons albeit of different areas to provide contiguous coverage. Each base station usually has a number of cell sites7 that use different frequencies and transmit in different directions from the base station and the pattern of hexagons is to assure the required ‘frequency re-use’ pattern to make best use of the available spectrum.
Radio transmission knowledge including propagation, radio system design and antenna principles
Telecommunications network engineering including call management and
charging principles And the areas of experience required are:
The specifics of cellular mobile engineering including radio network planning and design
Basic telecommunications network switching
It should be noted that experience of cellular radio network planning, design and practice including the radio systems elements, propagation and the capabilities of computer coverage prediction tools is a very specialised area.
5. Discussion of Cell Site Evidence Used in Australia
In mid July 2008 one of the authors contacted all Australian Directors of Public Prosecutions asking about their practice in the use of cell site information from mobile phone call charge records. The response from the various jurisdictions is summarised in Attachment 1.
Criminal Law Conference
Paper by Reg Coutts1 and Hugh Selby2