Samsung Electronics Co., Ltd.

Hee-Chan Doh

Tae-Sung Park

Yun-Je Oh

Gil-Yong Park

Shin-Hee Won

Hyeon-Cheol Ki

Byung-Chang Kang

Jeong-Seok Choi

Chan-Youl Kim

Gil-Young Park

A bottom level detection device is disclosed for a burst mode optical receiver. The receiver includes a converter for converting a burst mode signal into a voltage signal and an automatic gain controller for automatically controlling a gain of the converter. The bottom level detection device detects a bottom level of an output signal from the converter and controls the automatic gain controller on the basis of the detected bottom level. The bottom level detection device includes an amplification circuit for receiving the output signal from the converter at its first input terminal and a fed-back output signal from the device at its second input terminal, respectively, and amplifying a difference between the received signals, a detector for detecting a bottom level of an output signal from the amplification circuit, and an output buffer. The detector includes an RC rectifier for receiving a power supply voltage, and a transistor having its emitter connected to an output terminal of the amplification circuit and its base and collector connected in common to the RC rectifier.

Bottom level detection device for burst mode optical receiver

A burst mode optical receiver is disclosed and includes a converter for converting a burst mode signal into a voltage signal, a bottom level detector for detecting a bottom level of an output signal from the converter, an automatic gain controller for automatically controlling the gain of the converter on the basis of the bottom level detected by the bottom level detector in order to maintain an amplitude of the output signal from the converter and generating a reset signal when the bottom level is lower than a predetermined reference value, and a power level detector for detecting a power level of the output signal from the converter and generating the reset signal and an LOS signal indicative of the presence of no input signal when the detected power level is lower than a predetermined reference value.

Burst mode optical receiver

A burst-mode optical receiver of a differential-output structure is disclosed. The burst-mode optical receiver includes a trans-impedance amplifier for converting currents indicating the burst-mode signals into voltage signals, a bottom-level detector for detecting the bottom level of signals outputted from the trans-impedance amplifier, an automatic gain controller for automatically adjusting a gain to prevent the output waveforms of the tran-simpedance amplifier from being distorted after receiving the bottom-level signals detected by the bottom-level detector, a top-level detector for detecting the top level of signals outputted from the trans-impedance amplifier, a pair of resistors for generating a signal-reference voltage from the bottom- and top-level voltages, one side of each resistor being connected to the bottom- and top-level detectors, respectively, and the other sides of each resistor being connected to each other, and a differential buffer for receiving outputs from the trans-impedance amplifier and the signal-reference voltage from the pair of resistors and for eliminating the offsets generated from the bottom- and top-level detectors in order to supply two differential outputs.

Burst-mode optical receiver of differential output structure

In an optical receiver having a pre-amplifier for converting a current signal outputted from an optical detector to a voltage signal, a signal level detecting device is provided to provide an LOS (loss of signal) signal and a reset signal from the output of the pre-amplifier. The signal level detecting device comprising: a capacitor for receiving the output from the pre-amplifier; first and second transistors each consisting of an emitter and a collector connected to the output of the pre-amplifier and a base connected to the collector; a third transistor having a collector connected to the collector of the first transistor and an emitter connected to the collector of the second transistor; and, a common emitter circuit with a pair of resistors connected, respectively, to the emitter and collector of the third transistor and capable of detecting the level of a signal inputted from the collector of the third transistor.

Signal level detecting device for a burst-mode optical receiver

An automatic-gain-control device in an optical receiver is provided and includes a pre-amplifier for converting a current signal outputted from an optical detector to a voltage signal and a bottom level detector for detecting the bottom level from the output of the pre-amplifier, the automatic-gain-control device comprising a bottom signal-level-determining section for analyzing the bottom level from the bottom level detector and outputting a signal denoting the presence of a signal and a reset signal for initialization at intervals between packets; and an automatic-gain-control signal generating section for providing an automatic-gain-control signal by showing the presence of a signal, the automatic-gain-control-signal-generating section including a first transistor which turns on according to a signal from the bottom signal-level-determining section and a second transistor which is connected to a capacitor for charging or discharging a voltage applied by the first transistor, and the drain voltage of which becomes low when the capacitor is charged but becomes high when the capacitor is discharged.

Automatic gain control device for a burst-mode optical receiver

An automatic threshold control device for a burst mode optical receiver is disclosed. The receiver includes a converter that converts a burst mode signal into a voltage signal and an automatic gain controller for automatically controlling a gain of the converter, independently generating a reset signal and applying it to the automatic threshold control device. The automatic threshold control device is adapted to detect a voltage level of an output signal from the converter. The device includes a peak detector that detects a peak level of the output signal from the converter in response to the reset signal, a bottom level detector that detects a bottom level of the output signal from the converter in response to the reset signal, a pair of resistors having their one sides connected respectively to the peak detector and bottom level detector and their other sides connected to each other, the resistors generating a reference voltage on the basis of voltages of the peak level and bottom level, and a capacitor for storing the reference voltage.

Automatic threshold control device for burst mode optical receiver

A receiver in an optical network with a bit rate detection circuit for automatically detecting input signal data bit rates to automatically adjust the frequency of a voltage controlled oscillator in the receiver is disclosed. The receiver has a data rate detection and frequency adjustment circuit which automatically detects the data rate of an input signal and automatically adjusts the frequency of the VCO in the receiver in accordance with the data rate of the input signal. The data rate detection and frequency adjustment circuit detects the data rate of the input signal by converting the input signal into a DC voltage value that varies with respect to the data rate of the input signal.

Bit rate detection circuit and algorithm for optical networks

Disclosed is a bit rate discrimination device that accurately discriminates a bit rate regardless of variations in the operating temperature. A photoelectric converter converts an input optical signal into an electric signal, and a bit rate detector detects a bit rate of the optical signal from the electric signal and outputs a discrimination signal indicating the bit rate. A DC amplifier outputs a bit rate detection signal by amplifying the discrimination signal, and a temperature detector detects the operating temperature of the DC amplifier and outputs a temperature signal indicating the detected operating temperature. A variation amplifier outputs a temperature compensation signal by amplifying the voltage level difference between the temperature signal and a predetermined reference signal, so as to cancel variations in an output voltage of the DC amplifier according to the operating temperature. A voltage adder outputs a temperature-compensated bit rate detection signal by combining the bit rate detection signal with the temperature compensation signal. A bit rate discriminator determines the bit rate of the input optical signal depending on the voltage level of the temperature-compensated bit rate detection signal.

Growing community of inventors

Suwon-shi, South Korea

Hee-Chan Doh