A low-noise block converter (LNB, for low-noise block, or sometimes LNC, for low-noise converter) is used in communications satellite (usually broadcast satellite) reception. The LNB is usually fixed on or in the satellite dish, for the reasons outlined below.

Universal LNB

A universal LNB can receive both polarizations and the full range of frequencies in the satellite Ku or C band. Some models can receive both polarizations simultaneously through two different connectors, and others are switch able or fully adjustable in their polarization.

Here is an example of Universal LNB specifications:

• LO: 9.75 / 10.6 GHz.
• Freq: 10.7–12.75 GHz.
• NF: 0.7 dB.
• Polarization: Linear

Standard North America Ku-band LNB

By covering a smaller frequency range a LNB with a better noise figure can be produced. Pay TV operators can also supply a single fixed polarization LNBF to save a small amount of expense.

Here is an example of a Standard Linear LNB:

• Local oscillator: 10.75 GHz
• Frequency: 11.7-12.2 GHz
• Noise Figure: 0.5 dB
• Polarization: Linear

North America DBS LNB

Here is an example of an LNB used for DBS:

• Local oscillator: 11.25 GHz
• Frequency: 12.2-12.7 GHz
• Noise figure: 0.7 dB
• Polarization: Circular

C-band LNB

Here is an example of a North American C-band LNB:

• Local oscillator: 5.15 GHz
• Frequency: 3.6-4.2 GHz
• Noise figure: ranges from 15 to 100 kelvins (uses Kelvin ratings as opposed to dB rating).
• Polarization: Linear

Dual/Quad LNB's

Two or Four LNB's in one unit to enable use of multiple receivers on one Dish.

Monobloc LNB's

a unit consisting of two LNB's designed to receive satellites spaced close together. For example in parts of Europe Monoblocs designed to receive the Hotbird (13E) and Astra 1 (19E) satellites are popular because they enable reception of both satellites on a single dish without requiring an expensive and noisy rotator.