A Versatile Spectrum Shaping Scheme for Communicating Beyond Notches in Multi-Drop Interfaces”

This paper proposes a signal shaping technique to increase the data rate of high-speed SerDes communication systems over multi-drop bus interfaces. This scenario creates a channel with deep notches in its spectrum, and therefore the effective data rate in conventional systems is directly affected by the frequency of the notch. Our method uses a special temporal coding scheme such that the input data stream has a notch at the same frequency as the notch in the channel. In this way, channel notch does not fully deteriorate the incoming data sequence and therefore the receiver can successfully decode the transmitted data stream. Using this approach, the communication rate over a channel with notch located at fnotch can be increased from fb < 2 fnotch (conventional NRZ), to fb = M fnotch (M >= 2).