August EWJ 24 - Flipbook - Page 74
The Critical Role
of Cell Site Analysis
in Modern Criminal
Investigations
Cell site analysis has emerged as a pivotal technique in criminal investigations, offering
invaluable insights into the movements and communications of suspects.
A Senior Cell Site Analyst at IntaForensics, recently
presented a comprehensive CPD webinar highlighting the benefits and limitations of cell site analysis. This
article explores the key points from the presentation,
providing an expert overview for those interested in
the intricacies of this forensic communications
method.
Key Components of Cell Site Analysis
Our cell site expert explains that cell site analysis
typically involves three main components:
1. Call Data Record (CDR) Analysis: This involves examining patterns of usage, identifying the most frequently used cells, and determining common contacts
and the frequency of communication. This analysis
helps in understanding the routine and movements
of the device.
Understanding Cell Site Analysis
Cell site analysis involves the forensic examination of
mobile phone data to identify a geographic location
of a device at a specific time. This process leverages
Call Data Records (CDRs) provided by mobile network operators, which include details such as cell ID,
date, time, and duration of communications. When a
mobile device engages in activities like calls, texts, or
data sessions, these interactions are logged, enabling
analysts to consider the device's movements.
2. Cell Site Location Comparison: This step involves
comparing the locations of cell sites with known locations of interest in the investigation. It helps in establishing whether a device could have been in proximity
to significant locations at relevant times.
3. Radio Frequency Propagation Surveys (RF
Surveys): Conducting RF surveys involves measuring
the radio signal strength and coverage area of cell
sites. These surveys validate whether the cells appearing in CDRs provide service to the locations of interest. They are crucial in cases where precise geographic
validation is necessary.
The Basics of Mobile Communications
Mobile devices communicate via radio waves, which
transmit and receive signals to and from a network of
base stations, often referred to as cell towers or masts.
These masts support the radio antennas necessary for
facilitating mobile communications. The antennas are
typically positioned high up to minimise obstructions,
allowing signals to travel with fewer interruptions.
Much like beams of light from a lighthouse, radio
waves can be obstructed by physical barriers such as
buildings, hills, or dense foliage, affecting communication quality.
EXPERT WITNESS JOURNAL
These elements can be combined to build a robust
picture of a device's activity, although some cases
might not require a survey, relying instead on the
analyst's expertise to form an opinion based on
existing data.
Practical Applications and Case Studies
The theoretical understanding of cell site analysis is
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AUGUST 2024
