Systems and Methods for Transferring Single-Ended Burst Signal Onto Differential Lines, Especially for Use in Burst-Mode Receiver

Abstract

Systems and methods for transferring incoming single-ended burst signals of which at least one characteristic varies widely from burst to burst onto a pair of differential lines. The systems comprise an input for receiving an incoming burst signal, a signal adaptation block for adapting said widely varying characteristic and a single-ended-to-differential converter. In a first aspect a reset signal for resetting a settings determination block, which controls the signal adaptation block, is sent backwards over the differential lines, preferably using a common-mode signal. In a second aspect, a status freezing mechanism is employed for freezing the settings of the settings determination block after the end of the preamble of an incoming burst.

Description

FIELD OF THE INVENTION[0001]The invention relates to systems and methods for transferring incoming single-ended burst signals of which at least one characteristic varies widely from burst to burst onto a pair of differential lines. The systems and methods of the invention can for example be used in an optical receiver in optical fiber networks, especially if these networks require burst-mode transmission, in particular passive optical networks, for instance gigabit passive optical networks.BACKGROUND OF THE INVENTION[0002]Burst-mode transimpedance amplifiers (B-TIA), intended for use in the optical line termination (OLT) of gigabit passive optical networks (GPON), are preferably compliant to the ITU-T G.984.2 standard.[0003]Burst-mode TIA must handle the upstream burst-mode transmission with the property that the signals arriving at the OLT consist of a rapid sequence of bursts with widely varying amplitudes from burst to burst.[0004]Furthermore, to support the ITU-T G.984.2 class B...

AI Technical Summary

Benefits of technology

Enables fast and accurate gain optimization at the start of each burst, extending the dynamic range and integrating the transimpedance amplifier into standard packages without additional pins, ensuring efficient burst-mode operation with widely varying amplitudes.

Problems solved by technology

A major problem in the development of a TIA front-end for a GPON system is the fact that after each burst, a reset signal is needed to prepare the receiver circuitry for a next burst.

When the guard time between bursts can be shorter than the maximum number of consecutive identical digits in a burst, it is not possible to detect the guard time between bursts.

This makes it difficult to integrate a TIA for GPON applications into the industry standard 5-pins TO-can package.

However, if one wants an additional RSSI (Received Signal Strength Indication) pin, the same problem remains, i.e. additional pins are needed on the TO-can package.

When the guard time between bursts can be shorter than the maximum number of consecutive identical digits in a burst, it is not possible to automatically detect the guard time between bursts.

In that case prior-art variable-gain burst-mode transimpedance amplifiers require a reset signal to be provided externally, with the packaging problems as described before.

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