Some will say that CellSite analysis is not an exact science. To some extent that statement is true, although it is ambiguous and a little misleading. Armed with equipment that provides reliable survey data and with a good understanding of the principals involved. Well structured procedures will lead to the same conclusions time after time. 3gforensics manufacture and supply such equipment and via its training partners, provide comprehensive training to ensure that users can draw valid conclusions from the data gathered.
A cell site typically consists of multiple transmitter receiver pairs, associated control equipment and antenna. Each set of transmitter receiver pairs will normally have a unique identity or CellID. Though more complex configurations can be employed, a typical cell site might consist of three transmitter receiver sets referred to as Base Stations, each with a unique CellID, each feeding an antenna.
Cell Site antenna can direct radio waves in a particular direction and by careful design, limit the spread of the radio waves, effectively limiting the range and area over which the base station is said to 'cover'. Such an area is referred to as a 'Sector' Normally each sector is served by a base station and since each base station has a unique identity 'CellId' the area of coverage, 'sector' can be referred to by the unique CellId.
A base station propagates radio waves into a defined area, referred to as a sector.
A three sector site.
Here we depict a base station site comprising of three base stations, propagating in three different directions.
Location Based Survey
To establish the base station transmitter receiver pair that is providing service to a specifcc location, it is necessary to survey that location with equipment that is capable of receeving and logging the signals propagated by all base stations on a the network of interest or even all networks that cover that site, regardless of the signal strength or quality of service offered by those base stations. Once that data has been collected, best serving cell calculations can be carried out to determine exactly which base stations a mobile would use if at that location.
Total Coverage Survey
A note on Csurv
Within this text reference has been made to 3gforensics CSurv. Nothing in this text is specific to CSurv and CSurv provides its users with no information that could not be obtained from other competent survey tools such as Qualcomm CAIT, Ericsson TEMS or Rohde and Schwartz. CSurv is simply the solution available form 3gforensics, designed form ground up to meet the needs of the forensic and law enforcement environment. It is low cost, easy to use, reliable and fully supported with training tailored to the needs of its user base. For more information.
CSurv is a comprehensive tool for recovering network data “off air” from the radio spectrum used for the provision of mobile communications services. The primary role of CSurv is to harvest accurate and real-time data from the networks providing mobile communications services, GSM, UMTS & WiFi. By decoding and understanding this data the CSurv operator is able to map the availability of mobile communications services in a highly accurate manor specific to a location of interest.
Primarily a forensic tool designed for digital investigators, CSurv gives its operator an insight into the coverage of networks, and the infrastructure that manages user traffic. Paired with internal GPS, and a mapping solution, CSurv enables the recording of location and network information for post survey scrutiny.
Described as ‘mapping the DNA of the network’, mobile communications network surveying allows a forensic examiner to understand a network’s vast and sophisticated radio frequency topography and therefore predict where voice or data connections may have been initiated, received, handed off and also the likelihood of these events taking place.
As network operator coverage maps are largely based on theoretical assumptions derived from equipment specifications, CSurv provides an actual and real-time view of the network, which is constantly altered by ever-changing environmental conditions.
Providing the ability to harvest data from the most common publicly accessible radio networks GSM, UMTS & WiFi CSurv is a most comprehensive, compact tool in the forensic examiners armoury.