Types of Satellite Dishes

Although every satellite dish shares the same basic purpose, gathering and focusing a signal, they come in several distinct designs. The differences are mostly about where the reflector sits relative to the LNB and how the curve is shaped. Knowing the types helps you recognize what you are looking at and understand why the LNB arm points where it does.

Prime focus dishes

A prime focus dish is the classic deep, symmetrical bowl. The reflector is a full, circular section of a parabola, and the LNB sits dead center, directly in front of the dish, held out on arms or a tripod at the focal point. Because the feed sits in the middle of the beam, it and its supports cast a small shadow on the reflector, slightly reducing efficiency. Prime focus designs are common in large C-band dishes, where the size makes that small loss unimportant. The large sizes involved are discussed in satellite dish sizes.

Offset dishes

The offset dish is what most homes use. Rather than a full parabola, the reflector is a slice taken from the side of one, so its focal point sits below and in front of the bowl rather than at the center. This is why the LNB arm on a home dish appears to point up at the bowl from below, and why the dish looks like it is tilted more steeply than it is actually aimed. The advantage is that the LNB and arm sit out of the signal path, so they cast no shadow, making offset dishes efficient at small sizes. They also shed rain and snow better because they stand more vertically, which is a large part of why they became the standard for home installations.

Flat-panel and phased-array dishes

Not every "dish" is curved. Flat-panel antennas use a grid of small elements behind a flat face to achieve the same focusing effect electronically rather than with a reflector's shape. Some can even steer their aim without physically moving, which suits vehicles, boats, and low-orbit internet systems that must track satellites across the sky. These appear in many portable and marine products and in newer internet dishes, covered in Starlink and modern internet dishes.

Motorized and multi-satellite dishes

Any of the reflector types above can be mounted on a motor so the dish can swing across the arc of satellites and receive from several orbital positions in turn. Others use special multi-feed LNBs to catch two or three nearby satellites at once without moving. These setups are more complex to install and align, relying on a motor or a specialized multi-feed LNB rather than a plain fixed bracket.

Why the shape affects installation

The type of dish you have changes how you aim it, which trips up people who assume all dishes point the way they appear to. An offset dish is the classic example: because its focal point sits below the bowl, the reflector looks as though it is aimed at the ground or low on the horizon even when it is correctly locked onto a satellite high in the sky. Trying to "correct" that tilt by hand is a common mistake that only loses the signal. Prime focus dishes, by contrast, point roughly where they look. Knowing your dish type before you start adjusting saves a great deal of frustration, which is why our guide to dish direction treats the offset angle as a distinct step.

Which type do you have?

For the overwhelming majority of homes the answer is an offset dish, chosen for its efficiency at small sizes and its good weather-shedding shape. Larger and more specialized needs bring in the other types. Whatever the shape, the underlying job never changes, and the components inside are the same ones described in the parts of a satellite dish.

← Back to Basics & How It Works