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I am trying to figure out how timing recovery is used after equalization (or, being more correct, when the equalizer is in the timing recovery loop), having a T/2 fractional spaced equalizer and using the Gardner algorithm as timing error detector. The usual situation is to have the equalizer output at 1sample/symbol, by having downsampled, or combining the outputs of the even and odd filters. The latter is my case (case (a) in figure). But Gardner algorithm works at 2samples/symbol, so I wonder what I must do with the samples coming out from the even and odd filters. Must I multiplex the outputs of the two filters so I have a 2samples/symbol, as depicted in (b)?

(a)conventional situation, (b) equalization+time multiplex. + TED at 2 samples/symbol

Regards,

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Maybe that's a very late answer for that question, but anyway, let's answer about it for others who will read this post.

The idea of fractionally spaced equalizers is to upsampler the symbol by M time the sampling rate, and combining the output in order to choose the best sample. It means it will compare them one by one. I don't have more details because I'm still searching about that kind of equalizers

thanks

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