High-speed receiver architecture

摘要

A receiver (or transceiver) is selectable between a Gaussian mode and a non-Gaussian mode. In the non-Gaussian mode, a transformation block applies a non-linear transformation to signal samples to convert non-Gaussian noise in the signal samples to Gaussian or approximately Gaussian noise. In the Gaussian mode, the transformation block is bypassed. Samples are equalized using an equalizer configured to operate with a Gaussian or approximately Gaussian channel.

主权项

1. A transceiver for communication over a fiber, the transceiver comprising:
a host interface for receiving digital data, the received digital data in a host format; a laser driver port for generating an electrical signal modulated by the received digital data in electrical form, the electrical signal suitable for driving a laser driver; transmit path circuitry coupled between the host interface and the laser driver port; and receive path circuitry to receive an electrical signal representing an optical signal received from the fiber, and to provide the received electrical signal to the host interface, the receive path circuitry comprising:
an analog-to-digital converter that generates signal samples from the received electrical signal;a transformation block applying a nonlinear transformation to the signal samples to generate transformed samples, wherein the nonlinear transformation converts non-Gaussian noise in the signal samples to Gaussian or approximately Gaussian noise;a multiplexer to select between a first input and a second input depending on a mode of the receive path circuitry selectable between a Gaussian mode and a non-Gaussian mode, the first input coupled to receive untransformed samples from the analog-to-digital converter, the second input coupled to receive the transformed samples from the transformation block, the multiplexer selecting the first input when operating in the Gaussian mode, and the multiplexer selecting the second input when operating in the non-Gaussian mode;an equalizer configured to equalize the selected samples from the multiplexer, the equalizer configured to operate on a Gaussian or approximately Gaussian channel.