Counter Surveillance Systems
Hardware and software for Law Enforcement, Government & State Security Organisations
• GSM network anomaly survey
• GSM interception detection
• Legal and evidential support
Mobile phones have become part of daily life for billions of subscribers worldwide. The
mobile phone companies construct networks such that subscribers are provided with
the best reception and most complete cellular coverage possible. The most obvious
evidence of this is the increasing number of masts (BTS, Base Station Transceivers)
appearing alongside our road and rail networks and anywhere the mobile service is
It is important to have a knowledge of the footprint of cells associated with each mast
for the following reasons
• Mapping of the known BTS and cells is vital preparatory material for any
surveillance exercise which relies on mobile subscriber location or interception.
• Knowledge of the known and official BTS and cells will lead to rapid detection of
any new BTS and/or cells some of which may be unofficial. Many GSM
interception devices present themselves as a temporary unofficial components in
Delma provides both equipment and services for the accurate mapping of mobile
network BTS and cells and the detection and exposure of anomalies. These are
invaluable tools in counter surveillance.
Cell Site Surveys The mapping process involves the following
The process of surveying the mobile phone • Measurement of RF transmission levels at
infrastructure is designed to produce an accurate various points within the area of interest.
mapping of the reception footprint of a particular The higher the number of points the more
BTS (Base Transceiver Station). All BTS have one accurate the cell footprint will be known
or more cells associated with them and cells can • GPS readings taken simultaneously with
be of a variety of shapes. each set of transmission level readings.
• Off air identification of the MNC (Mobile
Although intended to be of a regular geometric Network Code i.e the service provider),
shape the reception footprint of cells may be LAC (Location Area Code) and Cell ID (Cell
modified by the presence of buildings, structures identity) of the cell being mapped.
and topographical features. • Off air identification of the frequency of
transmissions (e.g. 900, 1800 or
The antenna utilised for the transmission and 2100MHz)
reception of the RF based mobile phone service • Processing of the data into a database
can give rise to anomalies. It is vital to know and digital mapping system to provide a
how these anomalies influence the reception graphical representation of the cell and its
footprint of a given cell. supporting data.
• Comparison with historical data to
The accurate mapping of a single BTS and its determine changes.
associated cells is often referred to as a Cell Site
Cell coverage footprints can be of different shapes and sizes depending on the type and location of
Survey equipment and systems:
Cell Seekertm System I & II
Delma provides two levels of Cell Survey
In Cell Seeker System I the hardware comprises
a portable PDA loaded with software which
handles the taking of RF transmission readings,
cell data and GPS coordinates. The second part
of the system is a laptop based mapping
application which is responsible for download,
storage, mapping and reporting of the collected
The features of this system are:
• The PDA is highly portable and can be
taken into the most inaccessible of areas
for the taking of readings.
• The PDA has an in-built camera for the
capture of possible additional PDA in survey mode
• The PDA can act as a mobile phone
allowing data to be sent by SMS to the
• The PDA can access any 2G, 2.5G or 3G
• The PDA has in-built GPS (System II)
• The laptop may be vehicle based or office
based depending on tactical requirement
• The laptop is Windows based providing
the user with a variety of mapping options
(e.g. Mapinfo, Google Maps etc)
• The laptop has extensive storage
capabilities but can also be networked to
the organisation’s server network.
• The PDA and laptop can connect to each
other via BlueTooth or WiFi or direct cable
• Surveying can be carried out simply and PDA in survey mode with menu options
• In continuous mode the PDA will display
the presence of an Interceptor switch on.
Cell Seekertm Laptop System
In Cell Seeker System II the emphasis is on high
speed gathering of cell data from large numbers
of cells from a moving vehicle.
The hardware comprises a vehicle based laptop
fitted with multiple mobile network reception
units, a GPS receiver and roof mounted
The laptop is loaded with software capable of
rapid multi-network sampling for RF transmission
readings, cell data and GPS coordinates for each
set of readings.
The features of this system are:
• All networks are handled simultaneously
• Large geographical areas can be covered
• The PDA described in System I above can
be used by surveyors on foot to cover
areas inaccessible to the vehicle. SMS,
• The laptop combines the data capture and
• Data can be gathered at high speed (e,g
for Motorway cell mapping)
Cell Seeker back office system and counter surveillance purposes
enforcement evidencial purposes or security
Data collected from Cell Seeker systems, GSM mission purposes
interceptors and other devices may be securely • Reporting
and efficiently uploaded to the Cell Seeker back
office system. A full suite of storage and analysis
programs provide access to then following
• Storage of Base Transceiver Station (BTS)
data Storage of Cell information and BTS
• Auto upload of survey data with creation
of cell and BTS records as appropriate
• Screening and analysis of survey data
• Mapping of specific survey or mission data
to provide cell footprints for surveillance
The presence of a GSM surveillance device can be quickly detected through rapid comparison of cell
footprints with the “norm”. The example below shows the effect on the normal cell profile along a
particular route caused by the presence of a parked surveillance vehicle housing active GSM
interception equipment. The interception zone is marked in black. In this case the range of
interception was low.
Example Cell route profile showing anomaly due to an active GSM surveillance
Cell Survey Services
Delma employs experienced consultants who can be deployed with the required equipment to
perform training, independent cell mapping services in support of qualifying organisations.
Professionally prepared training material, reports, presentations and other supporting material are
provided as part of the service. The same consultants are available for advice and legal work.
For information contact: Email: firstname.lastname@example.org
Telephone: +44 1962 735859 Fax: +44 1962 735890
In writing to: Delma MSS Ltd., Newhouse Farm, Northington, Alresford, Hampshire SO24 9UB