What Is GNSS Multipath?
Multipath occurs when GNSS signals reflect off surfaces (buildings, water, terrain) before reaching the receiver. The reflected signal travels a longer path, causing the receiver to measure an incorrect distance to the satellite. This degrades positioning accuracy by 1-10 meters or more.
How Multipath Affects Drone Operations
- Urban inspection: Reflections from building facades cause position jumps
- Bridge survey: Steel and concrete create complex multipath patterns
- Agricultural spraying: Reflections from terrain and crops at field edges
- Forest monitoring: Tree canopies scatter signals before they reach the receiver
How Septentrio APME+ Technology Works
APME+ (A Posteriori Multipath Estimation) is a post-correlation technique that models and removes multipath errors from GNSS measurements. Unlike traditional narrow correlator techniques that only reduce multipath impact, APME+ actively estimates and subtracts the error contribution. This delivers more accurate code and carrier phase measurements in multipath-rich environments.
APME+ Performance Results
- Reduces code multipath error by 60-80% in urban canyons
- Improves RTK fix rate near reflective surfaces by 30-50%
- Maintains carrier phase tracking through moderate multipath where competitors lose lock
- Works on all frequencies without additional hardware
Related GNSS Products
- HB21 GNSS Box Receiver — All-in-one RTK receiver with 4G LTE, heading, and data logging
- HB6 GNSS Box Receiver — Compact RTK receiver powered by Septentrio Mosaic X5
- EV322 GNSS Receiver — Lightweight RTK receiver for UAVs and autonomous systems
- AIM+ Anti-Jamming Technology — Military-grade interference and spoofing protection
Browse our full GNSS receiver collection for professional UAV applications.
Frequently Asked Questions
What accuracy can I expect from this GNSS solution?
Septentrio GNSS receivers deliver 0.6 cm + 0.5 ppm horizontal and 1.0 cm + 1 ppm vertical accuracy with RTK. The exact performance depends on satellite geometry, atmospheric conditions, and correction data quality.
Does this work with ArduPilot or PX4 flight controllers?
Yes. Septentrio receivers output SBF protocol which is natively supported by both ArduPilot (GPS_TYPE=9) and PX4 (GPS_TYPE=9). Simply connect the UART interface and configure the GPS parameter for plug-and-play operation.
Can I use this receiver without an RTK base station?
Yes. You can use NTRIP corrections via a cellular connection, or use Galileo HAS (free satellite-delivered corrections on supported modules). For post-processing, the receiver logs raw data for PPK processing.
How do I order or get technical support?
Contact our sales team at sales@uav-gnss.com for pricing and availability. Technical documentation, integration guides, and configuration tools are available through our website resources section.
