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Cell Site Analysis
Cell Site Analysis is the technique of placing a Mobile Phone at a particular geographical location and can be accurate to within a few metres. Some network operators produce Extended Call Data Records (ECDR’s), these records are stored by the network operators when the mobile makes or receives a call, SMS or using GPRS for Internet services, however these records are only retained for a limited length of time. ECDR’s highlight the particular mast (or cell site), which connected the mobile phone at a given time. Using these ECDR’s IntaForensics cell site experts can produce detailed reports to give the likely positioning and movements of a mobile phone.
Cell Site Analysis services are generally used by law enforcement agencies and defence legal teams with the purpose of ensuring that a suspect or defendant was in the general vicinity of the scene of the crime or not at the time of the incident.
Using data provided by the mobile network operators and radio test measurements of the cell masts, our expert witnesses, are able to determine the geographical area where the mobile phone has been used. Dependent upon the cell site the mobile phone was connected to at the time; the geographical location can differ greatly between distances of a few metres in a building or built up area to as much as 30km in very rural areas.
Comprehensive mobile coverage radio measurements can be carried out along a specific route or in a static location. These measure actual cell site coverage and take into account atmospheric conditions and other obstructions such as buildings. The gathered information is used as the basis for producing detailed coverage maps, where the coverage areas of individual cell sites can be shown.
The Lawful acquisition and disclosure of communications data for law enforcement agencies is governed by the Regulation of Investigatory Powers Act 2000 (RIPA). All Police forces must make a proportionate request for disclosure and would normally only provide information regarding a specific incident.
Most service providers will supply call data Defence counsel if the mobile phone has been registered in their client's name during the relevant period and if the records still exist. Such requests are dealt with in accordance with the provisions of the Data Protection Act 1998 (DPA). Otherwise Service providers will only provide information regarding calls made or received if a Court Order has been obtained.
For more information on Cell Site Analysis services from IntaForensics call us on 0845 009 2600.