Optical fiber wireless transmission system

Abstract

The invention relates to an optical fiber wireless transmission system. The optical fiber wireless transmission system comprises a central station and a base station connected with the central station by an optical fiber link; the central station comprises a single-mode laser of a single-longitudinal-mode optical carrier wave for generating designated wavelengths, a radio frequency sine wave signal source for generating low-frequency radio frequency signals, a Mach-Zehnder modulator for modulating optical carrier waves, a direct-current bias voltage source for providing bias voltage for the Mach-Zehnder modulator, and a light intensity modulator; output ends of the single-mode laser and the radio frequency sine wave signal source are connected with an input end of the Mach-Zehnder modulator; the bias voltage of the Mach-Zehnder modulator is the half-wave voltage of the Mach-Zehnder modulator, the output signal of the Mach-Zehnder modulator is a zero-step and four-step sideband, and the output end of the Mach-Zehnder modulator is connected with the input end of the light intensity modulator; the input end of the light intensity modulator is also connected with a data signal source; an output signal of the light intensity modulator is output to the base station by the optical fiber link. The invention can generate a sideband mold with the frequency difference greater than a local oscillation signal by eight times, and a low-frequency local oscillation signal can be utilized for generating high-frequency millimeter waves.

Description

technical field [0001] The present invention relates to the field of wireless transmission, and more particularly, to an optical fiber wireless transmission system. Background technique [0002] With the rapid development of Internet services and interactive multimedia services such as IP TV (IPTV) and Video on Demand (VOD) and the popularization of modern 3G wireless Internet access, major breakthroughs have been made in wireless communication technology in recent years, and traditional broadband wireless access methods have become Can not meet the growing demand for broadband services. Optical fiber wireless communication (RoF, radio-over-fiber) has the characteristics of making full use of the huge bandwidth resources of optical fiber to reduce costs, and combining with the flexibility of wireless communication technology, it integrates wireless network and optical network into one that can increase the capacity of the access network. , and can reduce the operating cost ...

AI Technical Summary

Problems solved by technology

For the traditional double-frequency optical millimeter-wave generation method, if high-frequency millimeter-waves are to be generated, a high-frequency local oscillation signal source is required, thus increasing the cost of the optical fiber wireless communication system

Images