How Far Does a GPS Repeater Reach in a Hangar? Here’s What You Need to Know

If you’re installing a GPS repeater in an aircraft hangar, one question always comes up:

What’s the actual coverage range?

The honest answer is that a GPS repeater does not have a single fixed range. Its effective coverage depends on several factors, including hangar dimensions, antenna installation height, and the location of the aircraft’s GPS antenna.

What Affects GPS Repeater Range?

1. Power Limits (By Design)
   GPS repeaters are required to operate at very low power levels to prevent interference with outdoor GPS systems.In simple terms: they’re designed for short-range indoor use-not long-distance broadcasting.
2. Antenna Type – Choosing the Right One Matters
   The antenna you select has a major impact on coverage shape and reach:
   Omnidirectional antennas provide broad, even coverage with a shorter reach. They’re ideal for standard ceiling heights where most of the signal needs to propagate horizontally.
   Directional antennas focus the signal into a narrower beam with greater reach, making them well-suited for large hangars with high ceilings.
3. Hangar Construction
   Metal beams, walls, and-most importantly-the aircraft itself can weaken, block, or reflect GPS signals. Even small changes in layout or aircraft positioning can noticeably affect coverage.
4. Line of Sight
   GPS performs best with clear line-of-sight between the repeater antenna and the receiver. When the antenna can “see” the receiver, signal strength is maximized. If large structures, such as a fuselage, block that path, signal quality will degrade.

Typical Indoor Coverage (Realistic Expectations)

Most aviation-grade GPS repeaters typically provide:

• 15-20 m radius in small hangars with antennas installed at ground level or low mounting heights
• 20-30 m radius in mid-sized hangars where antennas are mounted higher, improving line-of-sight coverage
• Multiple repeaters for large hangars or complex spaces

Coverage is heavily influenced by physical obstructions. Large metal structures-such as aircraft fuselages, wings, engines, and ground support equipment-can create localized dead zones by blocking or reflecting signals. These areas are usually mitigated through strategic antenna placement or by adding supplemental repeaters.
Manufacturers generally quote 300-800 m² of coverage per repeater, depending on hangar layout, construction materials, antenna height, and overall line-of-sight conditions.

What This Means for Aircraft Maintenance

In real-world hangar operations:

• A single repeater typically covers the nose area for basic avionics checks.
• Full aircraft coverage usually requires two or three antennas.
• Many facilities perform isolation testing to ensure GPS signals do not leak outside the hangar.

How to Measure Your Actual Coverage

Verifying coverage is straightforward and only takes a few minutes:

1. Install the repeater and indoor antenna.
2. Use any GPS-enabled device (test equipment, smartphone, or avionics).
3. Start close to the antenna and confirm satellite lock.
4. Walk away slowly until the signal drops.
5. Repeat in all directions.

Your effective “radius” is the maximum distance at which you still achieve a stable satellite lock with usable signal-to-noise ratio (SNR).

Bottom Line

A GPS repeater’s range isn’t a fixed number-it’s shaped by your hangar and your installation choices.
That said, most environments support 15-30 meters of reliable indoor GPS coverage, with larger hangars requiring multiple repeaters for consistent performance.