Cell Site Analysis is a technique used to determine which cells a mobile telephone is likely to connect to given the features and behaviour of the mobile network at a particular geographical point or region of interest. A forensic cell site expert can correlate this information to the call data records provided by the mobile networks to determine possible locations of a mobile phone at the time of past connections.
The geographical area that a cell covers is determined by a combination of factors including the cell type, cell orientation, transmission power, the arrangement of other cells, network usage and the physical features of the locality. These cell characteristics are variable over time and therefore must be considered as part of a cell site analysis.
Some police forces use intelligence analysts to produce cell site mapping and/or conduct Radio Frequency Propagation Surveys (RFPS) as statements of fact. Due to the complexity of cell site analysis, however, these facts may not tell the whole story. For example, the Prosecution usually seek to demonstrate the cell site usage is consistent with their case, but this is rarely to the exclusion of other possibilities. It is important to consider the defendant’s account of their movements against the cell usage to assess which account, if either, is more likely given the cell site usage pattern.
Using specialist surveying equipment, the police conduct readings on 2G (GSM), 3G (UMTS), 4G (LTE) and, in some cases, 5G technologies on all UK and Ireland mobile telephone networks. They can take static readings inside or outside a location of interest or conduct drive surveys. We can review this data and also offer paper-study exercises where appropriate, which include analysis of the path profile from the cells in question to the target area to assess the impact of physical obstructions which may impede the signal.
Cell Site Experts at Keith Borer Consultants can provide guidance for securing the necessary information from network providers, as well as advising you on the possibilities which could be investigated. These can be of benefit in differentiating between the alternate accounts of events. We aim to provide easy to use mapping, an interpretation of the evidence and, more importantly, what it means for your case.
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