Abstract: An optical network system comprising an optical line terminal (OLT) and an optical network unit (ONU) coupled to the OLT and configured to communicate with the OLT via an optical signal. At least one of the OLT or the ONU comprises a closed-loop gain controlled transimpedance amplifier (TIA) comprising a first amplifier configured to receive an input signal, generate a main output signal by amplifying the input signal according to a gain factor of the first amplifier, and generate an auxiliary output proportional to the input signal, an average detector coupled to the first amplifier and configured to receive the auxiliary output, and determine an average of the input signal according to the auxiliary output, and a feedback loop coupled to the first amplifier and the average detector and configured to control the gain factor of the first amplifier according to the average of the input signal.

Abstract: An optical network system comprising an optical line terminal (OLT) and an optical network unit (ONU) coupled to the OLT and configured to communicate with the OLT via an optical signal. At least one of the OLT or the ONU comprises a closed-loop gain controlled transimpedance amplifier (TIA) comprising a first amplifier configured to receive an input signal, generate a main output signal by amplifying the input signal according to a gain factor of the first amplifier, and generate an auxiliary output proportional to the input signal, an average detector coupled to the first amplifier and configured to receive the auxiliary output, and determine an average of the input signal according to the auxiliary output, and a feedback loop coupled to the first amplifier and the average detector and configured to control the gain factor of the first amplifier according to the average of the input signal.

Abstract: The invention provides a linear burst mode receiver comprising a first amplifier connected to a photodiode adapted to detect an optical input burst signal, a second amplifier connected to said photodiode; and means for deriving the peak input current of the detected burst signal using said second amplifier. The invention further provides means for using the derived peak input current to adjust the gain of the first amplifier during the preamble of each burst, such that the output voltage swing of the first amplifier equals a given reference, independent of the strength of the optical input burst signal. The usage of the fast feed-forward automatic gain control mechanism solves the problems with gain switching and non-linearity prevalent in today's burst-mode receivers.

Abstract: The invention provides a linear burst mode receiver comprising a first amplifier connected to a photodiode adapted to detect an optical input burst signal, a second amplifier connected to said photodiode; and means for deriving the peak input current of the detected burst signal using said second amplifier. The invention further provides means for using the derived peak input current to adjust the gain of the first amplifier during the preamble of each burst, such that the output voltage swing of the first amplifier equals a given reference, independent of the strength of the optical input burst signal. The usage of the fast feed-forward automatic gain control mechanism solves the problems with gain switching and non-linearity prevalent in today's burst-mode receivers.

Abstract: The invention provides a variable gain amplifier system for use in a burst mode receiver, said system comprising an amplifier adapted to amplify a signal; a gain control module; a dc offset compensation module adapted to derive a compensation signal as a function of the amplifier gain. Compared to existing methods for dc offset compensation in variable gain amplifier, the system and method for dc offset compensation allows fast adjustment of rapidly changing dc offsets that occur in applications where the gain of the variable gain amplifier is adjusted rapidly.

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.

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.

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.

Abstract: The present invention is related to a circuit (1) for detecting activity in a burst-mode receiver. The circuit is arranged for receiving an input signal (2) comprising a preamble. The circuit comprises a differentiator (11) for detecting signal transitions in the input signal (2) whereby the preamble comprises information on operating said differentiator (11). In a preferred embodiment, the information is a time constant. The circuit further comprises an integrator (12) arranged for being fed with an output of the differentiator. The resulting signal is compared to a reference (16). If this reference is crossed, activity is detected. In an embodiment a front-end circuit is presented comprising next to a circuit for detecting activity, a reset circuit arranged for resetting the front-end circuit and a clock phase alignment circuit arranged for recovering the phase.