FM transmitter power consumption? - RF Cafe Forums

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Mr.Whatever
Post subject: FM transmitter power consumption? Posted: Thu Sep 28, 2006 8:56 am

Captain

Joined: Fri Apr 07, 2006 6:10 pm
Posts: 18
Hi all,

I'm really not that familiar with a design of an FM transmitter, but I wanted to know about its power consumption. Does the power consumption fluctuate depending on amplitude of the input signal or is it constant regardless if there is an input or not?

I'm assuming that the antenna impedance remains constant during its operation.

Thanks!

Top

IR
Post subject: Posted: Thu Sep 28, 2006 2:00 pm

Site Admin

Joined: Mon Jun 27, 2005 2:02 pm
Posts: 373
Location: Germany
Hello,

In FM modulation the frequency of the carrier changes as a function of the modulating signal (Data), therefore the output power remains constant and thus the power consumption. If there is no input signal, the modulator will still transmit in the same output power and in the carrier frequency (Without frequency deviation), so the power consumption will still remain the same.

Hope that this helps!

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- IR

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