Cell Site Analysis

Cell site analysis can be used to determine the likely geographic area in which a mobile telephone was used when a call was made or received. Logs (known as Call Data Records or CDRs) are maintained by the telephone companies that record various information regarding a cell phone call, this information includes the location of the mast(s) used to service a call along with the antenna (this is the Cell ID), which can help determine the approximate direction from the mast of the telephone during the call. An examination of these records along with a cell site survey can be used to prove or disprove a particular alibi.

CDR's can be obtained by the police or by a solictor with a court order and armed with the information from these CDRs a survey of the area of interest is carried out using specially modified mobile handsets. The data obtained from this survey can then be used to determine whether a telephone call could have been made on a particular cell and if so to determine the range of possible locations that the call could be made from.

It is a common misunderstanding that Cell Site Analysis can be used to place a mobile phone at a given address, although it should be kept in mind that it is usually only possible to place a handset in a particular geographical area, in urban sites this could be anywhere from a few hundred yards to a few miles from the cell site mast. In the countryside a particular cell can cover many miles. However, cell site analysis can often be used with confidence to say that a telephone could not be located in a particular area. For instance a call that is made in close proximity to a telephone mast may be located with a large intervening metallic building blocking the signal from the mast, in this instance a site survey could show that as the phone moves behind the building the serving cell is switched to an alternate mast that could be much further away.

We have undertaken numerous high profile cell site analysis assignments, most recently we worked on the murder of Rhys Jones and the transatlantic bombing conspiracy.