Pre-Distortion of Power Amplifiers MAX2010

[Shahnaz93]

Hi
I use Max2010 for correction in DVB-T Power Amplifier, but I am not getting any improvement above 4 dB.
Anyone can guide how to get optimum performance using Max2010?

 

[G4BCH]

The MAX2010 is an open loop predistorter the IMD improvement you get depends on how well the expansion curves match the compression curves of your amplifier. From what I remember it would match a class B amplifier reasonably well, but could not cope with a Doherty amplifier. I've only tried to use this IC once and after a lot of fiddling managed about 6dB improvement but it did not stay stable over temperature, which could be corected, or the bandwidth of the amplifier, which could not.
From your other thread, the SC1894 was much better, but only for wideband signals, it's not much good for multicarrier amplifiers with narrowband TDMA signals.

 

[Shahnaz93]

Thanks for your reply.Is the SC1894 suitable for DVB-T class AB amplifier with 8MHz bandwidth?

 

[G4BCH]

It should be OK, it claims an input bandwidth of around 75MHz, but that bandwidth has to contain the intermods you want to supress without significant distortion.
In your other thread cariban replied to say that he had used it sucessfully. I tried it on a wideband signal a few MHz wide IIRC and it seemed to work OK for that, but I didn't look at it in detail.