A Simple Method for Transmission with Reduced Crosstalk and Echo

Abstract

The special ZXtalk method for completely degenerate interconnections (CDI) is capable of providing reduced echo and crosstalk in multiconductor interconnections, using few circuit elements. The paper defines the method and provides a design example showing how the termination circuits can be simplified. The paper also introduces a new type of MIMO amplifier, and explains why it is particularly suitable for the transmitting circuits used in the example. The number of circuit elements required by the ZXtalk method for CDI is finally shown to be proportional to the number of transmission channels.

DSP-based multimode signaling for FEXT reduction in multi-Gbps links

“…The digital implementation of the encoder was proposed in [12], however there are practical issues with either of the two suggested methods. If the signals to be sent from the transmitter are in analog form, the digital processing block would have to perform sampling and processing at a Nyquist rate in order to preserve the signal shape.…”

“…For a completely degenerate multiconductor transmission line system (e.g. stripline), an implementation using analog circuits was suggested in [9]. The complexity of such a system for non-degenerate channels (e.g.…”

Echo-Free and Crosstalk-Free Transmission in Particular Interconnections

“…Table I tells us that, in this case: -for voltage-mode signaling, the TX circuits perform nontrivial linear combinations determined by while the RX circuits only use trivial linear combinations; -for current-mode signaling, the RX circuits perform nontrivial linear combinations determined by while the TX circuits only use trivial linear combinations. Nowadays, we know that a multiple-input and multiple-output (MIMO) series-series feedback amplifier (MIMO-SSFA) [8], [9] can be used to perform such non-trivial linear combinations with a good accuracy in a wide band. It was for instance shown that a MIMO-SSFA may provide enhanced transmission up to using 8 GHz bipolar transistors.…”

MIMO Series–Series Feedback Amplifiers

“…The MIMO-SSFA is used as a transmitting circuit in the interconnection scheme shown in Fig. 3, in which the special ZXtalk method for completely degenerate interconnections [2] [7, § IX] is implemented with a matched termination at both ends. Such a scheme is applicable to simultaneous bi-directional signaling with reduced echo and crosstalk.…”

“…Section III provides design equations. Section IV explains the design of a 4-input and 4-output MIMO-SSFA used as a transmitting circuit for a multiconductor interconnection [2]. Section V shows additional capabilities of the MIMO-SSFA.…”