Drive Testing in Cellular Analysis: Why Multi-Platform Capability Sets PCA Apart
- Kevin Horan
- 2 days ago
- 5 min read
A Case Study from United States v. Morgan (D.C. Cir. 2022)
By Kevin R. Horan, Precision Cellular Analysis (PCA)
Introduction
Cellular analysis plays a crucial role in modern litigation. Attorneys often rely on Call Detail Records (CDRs) and tower information to reconstruct where a device was likely located. But these records only tell part of the story.
CDRs reveal what tower the phone used.They do not explain why the connection occurred.
To understand that critical “why,” experts must measure the actual radio-frequency (RF) environment, and the only reliable method is drive testing.
Precision Cellular Analysis (PCA) is one of the few private cellular analysis firms in the country with multi-platform drive-testing capability. We have access to two separate RF-measurement systems—one based on active SIM-driven handset testing, the other based on SDR passive scanning. Depending on the case, PCA may use one system, the other, or both when enhanced validation is required.
This article explains why drive testing matters, how each platform works, and how PCA’s methodology was validated in United States v. Morgan (D.C. Cir. 2022).
What Drive Testing Measures
Drive testing involves physically traveling the relevant area with specialized RF-measurement equipment to collect:
Real signal-strength values
Sector dominance and tower-selection behavior
Neighbor-list relationships
Terrain and environmental impacts
Competing tower/sector coverage
GPS-synchronized RF logs
This data provides essential context missing from CDRs.
Drive testing addresses questions such as:
Was the tower in the CDRs the strongest, best quality signal at that spot?
Would a handset normally select a different sector?
Were buildings, terrain, or clutter influencing tower choice?
Do the CDRs match real-world RF conditions?
PCA’s Multi-Platform Drive-Testing Capability
PCA has access to two complementary, purpose-built RF measurement systems:
1. SIM-Based Handset Testing (Active Testing)
This platform uses a functioning device with a live SIM cards to measure:
Actual call, text, and data behavior
Real tower-selection and handoff patterns
Connection timing and RF conditions as experienced by a normal device
It answers:“What would the phone actually have done from this location?”
2. SDR-Based RF Scanning (Passive Network Measurement)
This system uses a software-defined radio (SDR) to:
Passively scan all tower broadcasts
Map coverage footprints
Identify dominant vs. fringe sectors
Measure competing or overlapping signals
It answers:“What is the full RF environment around this scene?”
Why Having Both Platforms Matters
Most private experts use only one system, if any.
PCA can choose the most appropriate platform or use both for redundancy. With our tools, PCA can:
Use the right tool for each case
Some cases require actual handset behavior; others require broad RF mapping.
Obtain the fullest possible RF picture
One system shows how towers behave.The other shows how phones behave.
Offer optional redundancy when the stakes demand it
High-profile criminal cases, wrongful-death litigation, complex insurance matters, or known Daubert challenges benefit from dual-platform validation.
Reduce vulnerability in cross-examination
Two independent sources of measurement data create a stronger, more defensible foundation for expert testimony.
This capability helped PCA’s methodology withstand intense scrutiny in federal court.
Case Study: United States v. Morgan (D.C. Cir. 2022)
PCA’s Expert Testimony Survived Rule 702 and Daubert Challenges
In United States v. Morgan, I served as the drive-testing and RF expert.
The defense challenged the validity of drive testing under Rule 702 and Daubert.
Both the district court and the D.C. Circuit upheld the methodology.
Key Findings:
1. Drive testing is a long-established, engineering-validated technique
The Court recognized that carriers and industry engineers rely on drive testing every day.
2. The method is testable, repeatable, and peer-reviewed
Real RF measurements are empirical and can be independently verified.
3. Critiques go to weight, not admissibility
Questions about route length or scope do not undermine scientific reliability.
4. Drive testing clarified tower-selection behavior for the jury
RF measurements helped explain why certain tower connections were likely or unlikely.
Morgan remains one of the strongest modern federal validations of drive testing as reliable scientific evidence — and the courts examined and upheld the methods I used in that case.
PCA’s Drive-Testing Workflow
1. Preparation
Review CDRs and carrier maps
Identify key towers and sectors
Analyze terrain and clutter
Choose appropriate drive-testing platform(s)
2. Field Testing
Active SIM-based handset testing
Passive SDR-based RF scanning
Optional dual-platform redundancy
Measurements collected during a drive test are logged with precise GPS coordinates and timestamps, allowing each RF observation to be mapped accurately.
3. Post-Processing
Analyze RF measurements
Compare to CDR patterns
Validate tower-selection behavior
Produce clear maps, charts, and courtroom-ready exhibits
When Attorneys Should Request Drive Testing
Drive testing is often requested in criminal and civil matters including wrongful death investigations, corporate employee location disputes, accident reconstruction, domestic relation issues (divorce, custody, etc.). Here are the top three reasons to ask for a drive test:
1. To validate (or challenge) whether the tower shown in the CDRs is the most likely tower at the location.
2. To confirm coverage limitations, behavior anomalies, terrain issues or competing towers that could alter the interpretation of CDRs
3. To determine whether two competing locations can be distinguished by tower coverage.
The last example is one of the more frequent applications of drive testing. What happens when two locations appear to fall under the same cell site, creating uncertainty? The argument becomes the same tower covers both locations, and the records cannot distinguish between them.
How drive testing resolves this:
A drive test can empirically determine:
Which tower or sector actually dominates each location
Whether the two locations share the same coverage footprint
Whether a device at Location A would normally connect to the same tower as Location B
Whether the CDRs are more consistent with one location and less consistent with the other
Whether terrain, clutter, or RF interference creates different coverage conditions despite proximity
Drive testing provides the ground truth needed to separate two locations that appear similar on paper but behave very differently in real RF conditions. Drive testing is simple to explain to juries, directly challenges assumptions made by investigators and provides objective measurements instead of speculation.
Conclusion
Drive testing is the single most powerful method for validating or challenging interpretations of cellular records. As courts demand greater scientific rigor, measurement-based analysis—not speculation—will define the future of cellular analysis.
With access to both SIM-based handset testing and SDR-based scanning systems, PCA delivers an unmatched level of precision, flexibility, and defensibility. Combined with testimony validated in United States v. Morgan, PCA remains at the forefront of cellular analytical science.
If your case involves tower coverage, handset location, or disputed cellular evidence, PCA can help.
About the Author
Kevin R. Horan is the Co-Founder of Precision Cellular Analysis and a retired FBI Supervisory Special Agent. He has testified as an expert in federal, state, and civil courts across the country and is recognized for his work integrating investigative techniques with advanced cellular analysis. Kevin served as the drive-testing expert in United States v. Morgan (D.C. Cir. 2022), where the federal courts upheld the scientific reliability of his methodology under Rule 702 and Daubert.