A device for enhancing extinction ratio, optical transmitter, optical receiver, and optical module

Abstract

The invention discloses a device for enhancing extinction ratio, an optical transmitter, an optical receiver and an optical module, which relate to the field of communication and can enhance the extinction ratio. The apparatus includes: a device composed of a material having a saturable absorption effect for passing an optical signal.

Description

technical field [0001] The invention relates to the communication field, in particular to a device for enhancing the extinction ratio, an optical transmitter, an optical receiver, and an optical module. Background technique [0002] With the continuous increase of users' demand for bandwidth and the maturity of optical fiber communication technology with huge bandwidth capacity, the optical fiber access network has become a strong competitor of the next generation broadband access network, especially the passive optical network (PON, Passive Optical Network) The system is more competitive. [0003] As the demand for access bandwidth increases, the transceiver rate of optical modules in the PON system will also continue to increase. However, for a PON system with a high modulation rate, even within a transmission distance of 20km, there will be an obvious dispersion penalty, which will lead to a serious decrease in system receiving sensitivity and serious degradation in tran...

AI Technical Summary

Problems solved by technology

For optical access modules with a modulation rate of 10G and above, EML can obviously solve the problem of signal distortion caused by dispersion, but the cost of EML is high, and it introduces a large insertion loss (6-8dB). High consumption

[0005] In order to reduce the cost, it is hoped to use a direct modulated laser DML (Direct Modulated Laser) with simple structure, easy implementation and low cost. DML modulates the output of the semiconductor laser by changing the injection current, but the modulation current will cause changes in the refractive index of the active layer. As a result, the phase of the light is modulated, and there is a large frequency chirp phenomenon, which leads to the use of DML only in the case of a low extinction ratio, but this will lead to a decrease in the sensitivity of the DML, and the extinction ratio is not within the range of the extinction ratio defined by the agreement. Inside

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