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When you use a RRC filter you add extra symbols at the end of your generated data because of the delay of the filter. When the data passes through the filter it gets up-sampled and the delay is introduced. However, the delay also introduces some zero, or near zero, valued parts to the signal, see figure. My doubt was, at the moment of sending the signal, are this parts also sent? Or you only take the non zero value parts?
That depends. But typically, yes, you'll flush out your transmit signal; that basically "costs" nearly nothing, but makes sure your spectral mask stays clean.
At the receiver, this part still contributes to the amplitude of the matched filter output for the last couple of symbols, so, albeit not contributing very much, omitting it would just introduce an error to these symbols.
