Overhead 1090 Guides · Antenna
Which ADS-B antenna should you buy?
Updated October 2026
The small antenna that comes with a USB radio does pick up aircraft. After that, most of the gain comes from four things: an antenna made for 1090 MHz, height, a short cable and, sometimes, a filtered preamp at the antenna.
The stock antenna or one made for 1090 MHz
The little whip bundled with most USB radios covers a wide range of frequencies. It works on a windowsill and is a fine way to start. An antenna made for 1090 MHz is tuned to the one frequency ADS-B uses, and outdoor models are built to live on a mast.
The common types are a ground plane (one upright element with a few sloping ones below it), a collinear (a tall, thin tube, usually the outdoor choice) and ready-made ADS-B antennas, which are mostly collinears in a weatherproof case. A ground plane is also an easy first build: a quarter wavelength at 1090 MHz is about 6.9 cm (2.7 in), so it takes a coax connector and a few short pieces of stiff wire.
Height and clear sky
Signals at 1090 MHz travel in straight lines, so the antenna hears only what it can “see”. Walls, roofs, trees and hills each cut your range in their direction. Moving the antenna from a window to the attic, or from the attic to a mast above the roofline, usually does more than swapping the antenna itself. Episode 3 explains why.
Outdoors, keep the mast well clear of power lines and ground it as your local electrical code requires.
Keep the cable short
Coaxial cable loses signal along its length, and the loss climbs with frequency, so at 1090 MHz it adds up quickly. Use the shortest run you can, and low-loss cable if the run has to be long. Many people put the radio and the small computer in the attic, right under the antenna, and run a network cable down instead of a long coax.
When a filtered preamp helps
A preamp, or low-noise amplifier (LNA), boosts the signal before the cable can lose any of it. It helps most when the cable to the radio is long, and it belongs at the antenna end, not next to the radio.
Pick one with a 1090 MHz filter. Phone masts and other strong transmitters nearby can overload a USB radio, and an unfiltered amplifier boosts that interference too. Many preamps take power up the coax (a “bias tee”), so check how yours is powered. With a short cable and a quiet radio neighborhood, a preamp may add little; lowering the radio's gain can matter as much.
See the difference
Change one thing at a time, then leave it running for a day or two, because traffic varies with the time of day. Overhead 1090 shows how far your own receiver reaches: range rings on the live map and the farthest aircraft in your reports, on iPhone, iPad and Apple TV. If you're starting from scratch, Episode 2 covers the whole station and the PiAware guide shows how to connect the app.
Overhead 1090 Explains
- Ep. 1: What is ADS-B?
- Ep. 2: What does an ADS-B receiver hear?
- Ep. 3: How far can an ADS-B receiver hear?
- Ep. 4: What's a squawk code?
- Ep. 5: Who's flying that?
See every plane over your house on iPhone, iPad and Apple TV: Overhead 1090 on the App Store, one purchase, no subscription.