## Eye diagrams for raised cosine filtered data

#### The effect of changing a on the time domain response of the data signal is readily seen from the eye diagram. As a is reduced, the eye opening dramatically narrows, requiring the accuracy of symbol timing to be even more exact. Additionally, it can be seen that the ‘overshoot’ of the pulse caused by the filtering is greater for small a, increasing the peak to mean ratio of the energy in the data signal, and hence the peak signal handling requirement of the modulator and demodulator circuits.

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