US Patent 7853149 Transmitter frequency peaking for optical fiber channels

Frequency peaking is used in the transmitter to improve link performance. In one example, frequency peaking improves the PIED or TWDP. The frequency peaking can result in pulse shapes that have more electrical energy in the receiver (and therefore higher received SNR) than uncompensated pulses. In addition, due to the response of typical fibers, boosting the high frequencies typically will flatten the received spectrum, which will improve the performance of the equalizer in an EDC receiver.