Testimony Flashcards
What 3 facts identify “general area” of phone upheld by multiple courts?
- Lat/Long-precise location of the cell site
- Direction-of the antenna
- Best signal-Antenna selected because it had the best signal
What is the anatomy of a cell tower?
A cell tower consists of sectors, antennas and radio transceivers.
What is a sector?
Most cell towers have antennas grouped into three distinct directions. Each group of antennas and the associated radios is called a sector.
What is an azimuth?
The direction an antenna/sector faces.
Why is the “closest” cell tower is not always “best” in regards to best signal?
- Terrain & obstructions
- Other cell sites/antennas
What defines “general location”?
-In the vicinity of the cell tower
-On the side the antenna faces (or very close to the antenna)
List the acceptable “theory of granulization
- Identifying the physical location of the cell site
- Identifying the specific antenna used
- Identifying the antenna direction
US V Jones
Maps showing cell tower locations and sector was acceptable. Graphics that might be mistaken as coverage areas were changed.
What are call detail records (CDRs)?
They are records maintained by the phone company of the voice calls, text messages, and data sessions related to a cellular device. They include date, time, who is talking to whom in terms of phone numbers, duration, and the cell site and sector (or side of the tower) used in making those connections.
What are cell tower lists?
They are lists provided by the cell phone companies which identify the locations of their cell sites by address and latitude and longitude and the direction each sector on that tower is facing.
What do you do with these records when you’re doing your analysis?
-Examine the call detail records to determine the times and connections that were made to the network either via voice calls, text messages or data sessions which are pertinent to the investigation.
-Identify the cell site locations and the sector’s direction used during pertinent connections and place on a map along with addresses associated with the case such as the crime scene.
-I use mapping software along with manually mapping records my hand.
-With this information I can determine where the general location a specific phone was located, during connections to the network.
Do the cellular service providers concern themselves with the accuracy of their networks and call detail records?
Yes, the cellular networks must maintain accurate records for their customer’s voice, text, data sessions for several reasons such as network operations, evaluating network performance and to be able to determine the cell site and sector used by a phone calling 911 as mandated by the FCC.
In most cases, has there been other evidence in the cases which supports the cellular location information?
Yes, often the cases I work have other evidence which supports the cellular information such as witness statements, GPS devices, and license plate cameras.
When you learn that a cell phone has engaged a certain tower’s sector, is there any way to know EXACTLY where that cell phone was located?
Can’t say EXACTLY where the phone was, for example at a specific address or intersection, but it can provide a general area of the cell phone.
What is a cell site
A physical location that is comprised of the equipment needed to receive and transmit radio signals for cellular voice and data transmissions.
