Passive optical network and its optical network unit optical module

Abstract

The invention discloses a passive optical network and an optical module of an optical network unit of the passive optical network. The optical module comprises a laser emitting unit; and the laser emitting unit comprises a laser device and a drive circuit of the laser device, and a temperature compensation circuit. The drive circuit is used for receiving an electric signal transmitted by an ONU (Optical Network Unit) system, and driving the laser device to emit laser according to the received electric signal; and the temperature compensation circuit is used for regulating the temperature regulation voltage output to a TEC built in the laser device, according to the variation of the resistance value of a thermoelectric couple built in the laser device. With the temperature compensation circuit, the central wavelength of the laser emitted by the laser device is protected from being influenced by the temperature and generating lager offset, and the stability of the central wavelength of the emitted laser is ensured, so that the frequency interval of uplink optical signal transmitting of different ONU optical modules can be smaller, and the bandwidth of the optical network in uplink direction is improved.

Description

Technical field [0001] The invention relates to optical fiber communication technology, in particular to a passive optical network and its optical network unit optical module. Background technique [0002] In such figure 1 In the passive optical network shown, the OLT (Optical Line Terminator, optical line terminal) is usually set in the central office of the access network system of the optical fiber communication system, and the OLT is responsible for converting the electrical signal data in the switch into optical signal data and sending it out , And receive the optical signal from the outside, convert it into an electrical signal and send it to the switch. OLT is connected to ONU (optical net unit, optical network unit) optical module through ODN (optical net unit). The ONU optical module is usually installed at the central office, that is, the user’s end or the building; Splitter is a "splitter" generally with 2N evenly divided If the light intensity of the input port is 1,...

AI Technical Summary

Problems solved by technology

However, the current WDM PON technology is only limited wavelength multiplexing based on CWDM (full-wave 16 wavelengths, generally only 4 wavelengths in the 1320 band are used), even if DWDM technology is introduced, it is limited by the externally modulated laser Due to the limitations of spectral width and wavelength temperature drift, the channel spacing is only controlled at 200GHz intervals (45 channels in C-band)

[0006] Therefore, the existing optical network cannot provide sufficient upstream channel bandwidth to meet the growing business needs

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