LNA Design for satellite receiver - RF Cafe Forums

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Jan

Post subject: LNA Design for satellite receiver

Posted: Sun May 15, 2005 3:05 pm

Lieutenant

Joined: Sun May 15, 2005 2:46 pm
Posts: 1

Can anyone tell me how it is possible to build a low noise amplifier with a gain of more than 50 dB and a noise figure less than 1 dB? Most LNB's of a satellite receiver have such good characteristics but most commercial IC's and MMIC's are far away from that.

Guest

Post subject:

Posted: Thu May 19, 2005 2:50 pm

The overall noise figure is dominated by the first stage in the design. You could cascade several amps and rig up a high gain low noise amp yourself. Only the first stage would have to be low noise, the rest don't have to.

Guest

Post subject:

Posted: Sat May 28, 2005 2:24 pm

what frequencies are we talking about?

Posted 11/12/2012

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