LINC Transmitter -> Output Combiner - RF Cafe Forums

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gregoryb
Post subject: LINC Transmitter -> Output Combiner Posted: Thu Jul 19, 2007 8:56 am

Captain

Joined: Sun Mar 06, 2005 8:02 am
Posts: 6
Hi,

I was reading about the LINC transmitter topology, in which a varying-envelope signal is converted into two constant envelope signals that can be amplified using two nonlinear amplifiers, and then combined to the orignal, but amplified signal.

I read in several places that this method is not commonly used due to the lack of appropriate combiner for the output signals. Why is that? What is the requirement for such a combiner, that a regular passive combiner (i.e. wilkinson), does not fulfil?

Thanks,
Gregory

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IR
Post subject: Posted: Mon Jul 23, 2007 1:10 pm

Site Admin

Joined: Mon Jun 27, 2005 2:02 pm
Posts: 373
Location: Germany
LINC transmitter toplology is mainly used for wideband modulation schemes such as OFDM and WCDMA. It is required that the combiner will be wideband. Wilkinson combiners/splitters are everything but wideband, therefore, they can't be used in LINC transmitters.

Posted 11/12/2012