Broadband radio frequency modulation circuit of laser

Abstract

The invention relates to the field of an optical communication technology and provides a broadband radio frequency modulation circuit of a laser. The circuit comprises a peaking inductor, a depletion type FET (field effect transistor) geminate transistor, a broadband impedance matching circuit, a broadband Bias-T circuit, an impedance transmission line and a matching resistor. In the technical scheme, as the broadband impedance matching circuit is used, the impedance matching can be flexibly reduced, thus realizing non-loss transmission of a radio frequency signal, achieving the high-efficiency modulation of the laser within a frequency range from 0.45GHz to 10GHz, and well meeting the requirement of an RoF (radio-over-fiber) system on transparent transmission of radio frequency bands of GSM (Global System For Mobile Communication), WCDMA (Wideband Code Division Multiple Access), 802.11a / b / g, WiMax, LTE and the like in the next-generation wireless communication system.

Description

technical field [0001] The invention relates to the technical field of optical fiber communication, in particular to a laser broadband radio frequency modulation circuit. Background technique [0002] In optical fiber communication systems, the small-signal impedance of the active region of the semiconductor laser is very small when it is working normally, and can usually be ignored. However, as the operating frequency of the radio over fiber (RoF, Radio over Fiber) communication system increases to the microwave or millimeter wave band, for the direct modulation system, the laser modulation performance will be greatly affected by the parasitic parameters of the laser chip package and the transmission line parameters. Therefore, it is usually necessary to achieve impedance matching between the laser chip and the laser modulation circuit. [0003] The commonly used RF system impedance is mostly 50Ω. In order to reduce the reflection coefficient of the laser modulation circui...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the shortcomings of the prior art, the present invention provides a laser broadband radio frequency modulation circuit in order to solve the problem of low laser modulation efficiency in the prior art

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