How to VSAT work?

How VSAT Work

i. The size of a VSAT antenna varies. The feedhorne directs the transmitted power towards the antenna dish or collects the received power from it.

ii. It consists of an array of microwave passive components. Antenna size is used to describe the ability of the antenna to amplify the signal strength.

iii. The Radio Frequency Terminal (RFT) is mounted on the antenna frame and interconnected to the feed-horn (outdoor electronics) includes Low Noise Amplifiers (LNA) and down-converters for amplification and down conversion of the received signal respectively .

iv. LNAs are designed to minimize the noise added to the signal during this first stage of the converter as the noise performance of this stage determines the overall noise performance of the converter unit. The noise temperature is the parameter used to describe the performance of an LNA.

v. Up- converters and High Powered Amplifiers (HPA) are also part of the RFT and are used for up converting and amplifying the signal before transmitting to the feed-horn. The Up/Down converters convert frequencies between intermediate frequency (IF level 70 MHz) and radio frequency.

vi. Extended C band, the down converter receives the signal at 4.500 to 4.800 GHz and the up converter converts it to 6.725 to 7.025 GHz. The HPA ratings for VSATs range between 1 to 40 watts.

vii. The Outdoor Unit (ODU) is connected through a low-loss coaxial cable to the indoor unit (IDU). The typical limit of an (Inter Facility Link) IFL cable is about 500 feet. The IDU consists of modulators that superimpose the user traffic signal on a carrier signal. This is then sent to the RFT for up conversion, amplification and transmission.

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