Time filter

Source Type

Wuhan Telecommunication Devices Co. | Date: 2013-05-22

Provided is a working point controlling device and method for applying MZ modulator, which includes: a light modulator; a transimpedance amplifier, transmits current outputted by PD of the modulator into voltage signal; a low-noise amplifier, detects low-frequency signal and amplifies the signal, in order to improve the signal/noise ratio; a high Q band-pass filter, detects error signal and amplifies the signal, in order to improve the signal/noise ratio; a first power level conditioning, performs power level condition on error signal of phase, in order that signal output meets A/D input rang; a micro processor, generates low-frequency signal and finishes software synchronization detection wave and ratio integration PI adjusting algorithm; a second power level conditioning, finishes D/A output voltage condition, in order that D/A output is able to meet direct current offset whole controlling range power voltage range of the light modulator. Applying present invention, the problems, that the hardware controlling circuit of current MZ modulator offset point is complex and controlling accuracy is not high, can be resolved.

Wuhan Telecommunication Devices Co. | Date: 2012-07-16

Disclosed is a portable downloader comprising a pen-shaped housing and a circuit board provided inside of the pen-shaped housing. Provided at one end of the circuit board is a micro-universal serial bus (MUSB) port. Connected to the circuit board are a ground wire and two data wires. Each data wire is connected to a probe at the other end. Provided at the end of the pen-shaped housing corresponding to the MUSB port is a socket. Provided at the other end are two position-fixing holes. The two probes penetrate the position-fixing holes. The MUSB port connects to a computer universal serial bus (USB) port through a USB-MUSB computer extension wire. The portable downloader uses USB power supply with no need for an external power supply, and supports hot plug. The downloader uses the two probes as the C2 port, and is convenient to transmit data to C2 slave devices. The downloader is of a pen-shaped packaging, and is therefore easy to carry.

Wuhan Telecommunication Devices Co. | Date: 2010-02-04

A side-coupling optical fiber assembly comprises a first substrate (

Wuhan Telecommunication Devices Co. | Date: 2012-12-17

An in-application upgrade method is used for optical module firmware not breaking a service. A storage area for internal programs of an optical module is divided into two areas which are respectively used for storing upgrade and application programs, and is divided into an area for backing up an interrupt vector table of a Boot program. An upper computer is in communication with the optical module. The interrupt vector table is switched, and the jump between the Boot program and the application program is achieved. The method includes extracting the contents of firmware, entering a download mode and updating the firmware. The original firmware is erased, and new firmware is written. An application mode is entered, the upper computer sending an exit command from the download mode. The upgrade program exits and a new application program is executed. The optical module operates normally without interruption.

Wuhan Telecommunication Devices Co. | Date: 2013-12-26

Provided are a silica-on-silicon-based hybrid integrated optoelectronic chip and a manufacturing method therefor. The hybrid integrated optoelectronic chip comprises a silicon substrate (

Discover hidden collaborations