How GPS Receivers See Weak Signals by Combining Data
A method for improving GPS sensitivity by mathematically combining multiple, weak signal samples to extract navigation data that would otherwise be lost in noise.
Original patent title: “Method and apparatus for signal processing in a satellite positioning system”
A method for improving GPS sensitivity by mathematically combining multiple, weak signal samples to extract navigation data that would otherwise be lost in noise. Granted to SnapTrack Inc in 2004 with 89 claims and 76 forward citations.
Key facts
Coverage
What does this patent actually cover?
This patent describes a way to make GPS receivers work in difficult environments, such as indoors or in urban canyons where satellite signals are very faint. The receiver captures multiple versions of the same signal over time. Because these signals contain repetitive data, the receiver can mathematically combine or 'sum' these samples. To ensure the final result is as clear as possible, the system weights each sample based on its signal-to-noise ratio, effectively giving more importance to the cleaner data. This process allows the device to pull usable navigation information out of what would otherwise appear as random background noise.
The gap
What does this patent NOT cover?
- Does not cover GPS signal processing that relies solely on a single, instantaneous signal capture.
- Does not cover methods that do not involve weighting the samples based on the signal-to-noise ratio.
- Does not cover hardware-agnostic software that does not interact with satellite positioning system signals.
- Does not cover non-repetitive data streams that lack common information between signal samples.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The invention treats time-separated, weak signal samples as pieces of a puzzle that can be aligned and summed to boost the signal strength, rather than discarding them as interference.
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Assisted GPS (A-GPS) in smartphones
Indoor positioning systems
Wearable fitness trackers with GPS
Why it matters
The bigger picture
This technology was essential for the transition of GPS from specialized outdoor equipment to the standard feature found in every modern smartphone. By allowing devices to acquire a location fix in challenging conditions, it enabled the rise of mobile location-based services, ride-sharing apps, and personal navigation.
Filed
May 6, 1998
Granted
November 9, 2004
Market context
Who's building on this
Companies in this space
SnapTrack was acquired by Qualcomm, which integrated this technology into its baseband chipsets. Today, major semiconductor companies like Broadcom, MediaTek, and Apple continue to refine these signal-processing techniques to improve GPS accuracy in increasingly dense urban environments.
Market impact
This patent helped solve the 'cold start' and indoor sensitivity problems that plagued early GPS devices. It effectively enabled the mass-market adoption of location services by ensuring that mobile devices could maintain a reliable lock on satellites even when the signal was significantly degraded.
Claim 1 — Plain English
What this patent covers
This patent describes a way to make GPS receivers work in difficult environments, such as indoors or in urban canyons where satellite signals are very faint. The receiver captures multiple versions of the same signal over time. Because these signals contain repetitive data, the receiver can mathematically combine or 'sum' these samples. To ensure the final result is as clear as possible, the system weights each sample based on its signal-to-noise ratio, effectively giving more importance to the cleaner data. This process allows the device to pull usable navigation information out of what would otherwise appear as random background noise.
The clever bit
The invention treats time-separated, weak signal samples as pieces of a puzzle that can be aligned and summed to boost the signal strength, rather than discarding them as interference.
What it does not cover
- Does not cover GPS signal processing that relies solely on a single, instantaneous signal capture.
- Does not cover methods that do not involve weighting the samples based on the signal-to-noise ratio.
- Does not cover hardware-agnostic software that does not interact with satellite positioning system signals.
- Does not cover non-repetitive data streams that lack common information between signal samples.
Patent timeline
Application submitted to the patent office
Application published, typically 18 months after filing
Patent officially issued
PatentBrief Score
Impact Score
Moderate
Citation count
38/40
Highly cited
Claim breadth
20/20
Very broad protection
Recency
0/20
Older than 20 years
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$65K – $207K
Midpoint $130K · expired or expiring · industry ×1.5
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
The original legal language
Original claims
89 claims as filed with the patent office.
Concepts involved
Citations
Patent lineage
Cite this patent
Krasner, N. F. (2004). How GPS Receivers See Weak Signals by Combining Data (U.S. Patent No. 6,816,710). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/6816710/reusable-launch-vehicle-falcon-9-booster-landing
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does How GPS Receivers See Weak Signals by Combining Data cover?
A method for improving GPS sensitivity by mathematically combining multiple, weak signal samples to extract navigation data that would otherwise be lost in noise.
Who owns patent US 6816710?
SnapTrack Inc owns this patent, granted in 2004.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 6816710 cited by?
This patent has been cited by 76 later patents that build on its ideas.
What problem does this patent solve?
This technology was essential for the transition of GPS from specialized outdoor equipment to the standard feature found in every modern smartphone. By allowing devices to acquire a location fix in challenging conditions, it enabled the rise of mobile location-based services, ride-sharing apps, and personal navigation.
What does this patent NOT cover?
Does not cover GPS signal processing that relies solely on a single, instantaneous signal capture.
Patent monitoring