High-speed mobile wireless communication system based on FPGA

Abstract

The invention discloses a high-speed mobile wireless communication system based on an FPGA. Base stations are arranged along an optical fiber at preset intervals, a 2.5 G synchronous ring network is formed among the base stations, the 2.5 G synchronous ring network is connected with a monitoring center, and broadband communication is carried out between a mobile terminal and the base stations. Timing and carrier synchronization are realized between the mobile terminal and the base stations, the uplink rate and the downlink rate adopt an asymmetric mode capable of configuring uplink and downlink rate ratios, and the communication rate is automatically configured according to the number of the mobile terminals accessed to the base stations at the same time. The base stations and the adjacentbase stations coordinate to determine a communication mode of a downlink channel and an uplink channel, so that smooth switching of the mobile terminal between different base stations is realized. Both the base stations and the mobile terminal comprise modems. Through the technical scheme of the invention, the asymmetric rates of the upper and lower channels are realized, the base stations can automatically adjust the communication rate of each terminal according to the number of accessible terminals, and the seamless switching problem of the mobile terminal in the high-speed mobile communication process is solved.

Description

technical field [0001] The invention relates to the technical field of communication systems, in particular to an FPGA-based high-speed mobile wireless communication system. Background technique [0002] In recent years, with the rapid development of science, technology and economy, my country's transportation construction has developed rapidly. Therefore, more and more people choose high-speed rail or cars as travel methods, resulting in an increasing frequency of mobile terminals appearing in high-speed moving scenarios. Since the mobile terminal is in a state of high-speed movement, it will cause Doppler frequency shift, which makes it difficult to receive synchronously in the OFDM (Orthogonal Frequency Division Multiplexing) system, and cannot guarantee the quality of the communication link. [0003] At present, some scholars focus on using the redundant information of the cyclic prefix to achieve synchronization. Considering the defects of the cyclic prefix, a new timin...

AI Technical Summary

Problems solved by technology

Although the synchronization algorithm combined with pilot or preamble symbols can realize the synchronization of the OFDM system, it is mainly verified by the simulation system, and has not been tested in combination with specific hardware devices.

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