LNB stands for low-noise block down converter, is the receiving device mounted on satellite dishes used for satellite TV reception, which collects the radio waves from the dish. Also called a low-noise block, LNC (for low-noise converter), or even LND (for low-noise down converter), the device is sometimes wrongly called an LNA (low-noise amplifier).
The LNB is a combination of low-noise amplifier, frequency mixer, local oscillator and IF amplifier. It receives the microwave signal from the satellite collected by the dish, amplifies it, and downconverts the block of frequencies to a lower block of intermediate frequencies (IF). This downconversion allows the signal to be carried to the indoor satellite TV receiver using relatively cheap coaxial cable; if the signal remained at its original microwave frequency it would require an expensive and impractical waveguide line.
Input Frequency | 1).Low Band:10.70 GHz -11.70GHz 2).High Band:11.70 GHz -12.75GH |
Output Frequency | 1).Low Band:950-1950MHz 2).High Band:1100-2150MHz |
L.O. Frequency | 1).Low Band:9.75GHz(1MHz@25℃) 2).High Band:10.6 GHz(1MHz@25℃) |
L.O. Stability | 1).Low Band:±1MHz(-40℃to+70℃) 2).High Band: ±1MHz(-40℃to+70℃) |
Noise Figure | 0.3 dB |
Conversion Gain | ≥65dB |
Gain Flatness | ≤+/-2dB |
Input VSWR | 2.5:1(max) |
Output VSWR | 2.0:1(max) |
Output Connector | F-female Connector |
Output Impedance | 75Ω |
Cross Polar Isolation | 20dB(min) |
Supply Voltage | 1)Ca:11.5-14.0v(Vertical Polarization) 13VDCType 2)Cb:16.0-19.0v(Horizontal Polarization)18VDCType |
Direct Current | 150mA |
Control Signals | 1).Low Band:Ca or Cb(see below) 2).High Band:Cc or Cb(see below) 3)Cc:continues 22KHz |
Operating Temperature | -40℃to+70℃ |
Storage Temperature | -40℃to+80℃ |
Relative Humidity | 0%-95% |
Phase Noise | 1)-50dBc/Hz@1kHz(max) 2) -75dBc/Hz@10kHz(max) 3) -95dBc/Hz@100kHz(max) |
Image Rejection | 45 dB (min) |