Patent classifications
H04B10/693
OPTICAL RECEIVING DEVICE
An optical receiving device includes a conversion module, a signal generation module and a control module. The conversion module performs photoelectric conversion and amplification on an optical signal to generate a photocurrent, the signal generation module provides a gain signal, performs transimpedance and amplification on the photocurrent according to an input signal indicating a preset output voltage swing to generate a voltage signal, and generates a measurement signal indicating an average optical power associated with the optical signal according to the photocurrent, the control module outputs a control signal which is variable to adjust a gain of the conversion module, so that a dynamic range of the conversion module changes as the gain of the conversion module itself changes.
OPTICAL RECEPTION DEVICE, STATION-SIDE DEVICE, PON SYSTEM, PREAMPLIFIER, OPTICAL RECEPTION METHOD, AND METHOD FOR SUPPRESSING OUTPUT INVERSION OF INTEGRATOR
An optical reception device includes: a light receiving element; an amplifier which receives and amplifies a current based on an input current from the light receiving element; a direct-current adjustment circuit which removes an offset current included in the input current; an alternating-current adjustment circuit which causes a part of the input current to flow therein; and a controller which controls the direct-current adjustment circuit and the alternating-current adjustment circuit. The controller includes an integrator configured to integrate an output of the amplifier and output a resultant output to two electric paths of a positive phase and a negative phase, and an inversion suppression circuit configured to operate so as to inject a current to the positive phase and extract a current from the negative phase when a negative phase potential of an output of the integrator is higher than a positive phase potential thereof.
OPTICAL RECEIVER
An optical receiver is disclosed, including an optoelectronic detector, a transimpedance amplification (TIA) circuit, a single-ended-to-differential converter, an I/O interface, and a controller. The optoelectronic detector, having bandwidth lower than required system transmission bandwidth, converts an optical signal into a current signal. The TIA circuit compensate gain for the received current signal based on a received control signal, to obtain a voltage signal, where a frequency response value of the current signal within first bandwidth is greater than that within the bandwidth of the optoelectronic detector, and any frequency in the first bandwidth is not lower than an upper cut-off frequency of the optoelectronic detector. The single-ended-to-differential converter converts the voltage signal into a differential voltage signal. The I/O interface outputs the differential voltage signal. The controller generates the control signal based on the differential voltage signal. The optical receiver disclosed can reduce costs while ensuring signal quality.
RECEIVER OPTICAL SUB-ASSEMBLY, BI-DIRECTIONAL OPTICAL SUB-ASSEMBLY, OPTICAL MODULE, AND OPTICAL NETWORK DEVICE
This application provides a receiver optical sub-assembly, a bi-directional optical sub-assembly, and an optical network device to improve anti-electromagnetic crosstalk performance of the receiver optical sub-assembly. The receiver optical sub-assembly includes: a photodiode, a trans-impedance amplifier, and a first filter component. The photodiode is configured to convert an optical signal into an electrical signal, a positive electrode of the photodiode is connected to an input terminal of the trans-impedance amplifier, and a negative electrode of the photodiode is configured to connect to a power supply. The trans-impedance amplifier is configured to amplify the electrical signal output by the photodiode, a power terminal of the trans-impedance amplifier is configured to connect to a power supply, and a first ground terminal of the trans-impedance amplifier is configured to connect to an external ground.
Analog front-end
Examples described herein relate to an analog front-end (AFE). The AFE includes a trans-impedance amplifier to receive an input current and generate a pair of the differential voltage signals based on the input current and a reference current. Further, the AFE includes a dynamic voltage slicer to receive the differential voltage signals at input terminals and supply digital voltages at output terminals. The dynamic voltage slicer includes a preamplifier to generate a pair of intermediate voltages based on the differential voltage signals sampled at a predetermined frequency. The dynamic voltage slicer also includes a voltage latch circuit coupled to the preamplifier, wherein the voltage latch circuit is to regenerate a pair of digital voltages based on the pair of the intermediate voltages. Moreover, the AFE includes a logic latch coupled to the dynamic voltage slicer to provide digital output states based on the pair of the digital voltages.
OPTO-ELECTRONIC ASSEMBLIES
An assembly of electronic components for reception of data using an optical fibre wherein said assembly comprises: a photodiode; a first amplifier coupled to said photodiode; a second amplifier, whose electrical behaviour is substantially identical to an electrical behaviour of said first amplifier; an impedance network comprising at least two electronic components coupled between an input of said second amplifier and a reference terminal, wherein those at least two electronic components comprise at least two impedance elements, one impedance element being capacitive and another being resistive or inductive, and wherein said at least two electronic components are adjustable under electronic control to adjust the impedance presented by said impedance network; and circuitry for creating a signal formed from a subtraction of outputs of the first and second amplifiers.
Optical receiver
An optical receiver is disclosed, including an optoelectronic detector, a transimpedance amplification (TIA) circuit, a single-ended-to-differential converter, an I/O interface, and a controller. The optoelectronic detector, having bandwidth lower than required system transmission bandwidth, converts an optical signal into a current signal. The TIA circuit compensate gain for the received current signal based on a received control signal, to obtain a voltage signal, where a frequency response value of the current signal within first bandwidth is greater than that within the bandwidth of the optoelectronic detector, and any frequency in the first bandwidth is not lower than an upper cut-off frequency of the optoelectronic detector. The single-ended-to-differential converter converts the voltage signal into a differential voltage signal. The I/O interface outputs the differential voltage signal. The controller generates the control signal based on the differential voltage signal. The optical receiver disclosed can reduce costs while ensuring signal quality.
Transimpedance amplifiers
The application describes a transimpedance amplifier circuit having a first circuit branch extending between first and second supply nodes. An input NMOS transistor is located in the first circuit branch, with its drain terminal coupled to the first supply node via a load resistor, its source terminal coupled to the second supply node and its gate terminal coupled to an input node for receiving an input signal. The circuit includes a PMOS transistor having its source terminal coupled to a third supply node, its drain terminal coupled to the first circuit branch, at a node in a part of the first circuit branch extending from the drain terminal of the input transistor to the load resistor, and its gate terminal coupled to the input node. A drain current of the PMOS transistor contributes a proportion but not all of a drain current for input NMOS transistor.
Reception device
A reception device includes a measurement unit that measures a first number of times for which a first phase and a first reverse phase based on a differential signal obtained by amplifying a signal based on noise intersect with each other, the first reverse phase being a reverse phase of the first phase, an oscillator that transmits a first signal, a comparison unit that compares the first number of times with a predetermined first reference value, and a signal output unit that outputs a second signal indicating that an optical signal has been received when the first number of times and the first reference value coincide with each other. The measurement unit resets the first number of times when the first signal is received.
Transimpedance amplifier for converting electrical currents to voltages
The disclosure provides an improved transimpedance amplifier (TIA) that can operate at a higher bandwidth and lower noise compared to conventional TIAs. The TIA employs a data path with both feedback impedance and feedback capacitance for improved performance. The feedback impedance includes at least two resistors in series and at least one shunt capacitor, coupled between the at least two resistors, that helps to extend the circuit bandwidth and improve SNR at the same time. The capacitance value of the shunt capacitor can be selected based on both the bandwidth and noise. In one example, the TIA includes: (1) a biasing path, and (2) a data path, coupled to the biasing path, including multiple inverter stages and at least one feedback capacitance coupled across an even number of the multiple inverter stages. An optical receiver and a circuit having the TIA are also disclosed.