Base station transmission signal orthogonalizing method and system in OFDM access base station

Abstract

Orthogonal method of base station emitting signal in OFDMA system is disclosed, the emitting end includes: coding, interlacing and modulating the original information bit; the sub carrier with the same interval is distributed to a sub channel; and the channel is divided into area edge user channel and center area channel; information symbol modulated is mapped to corresponding sub carrier; two arts of channel are orthonormalized separately; for user of area edge, according to result of step b), the OFDMA symbol is divided into corresponding sections which are equal; every section is multiplied with corresponding orthonormalized sequence of the area; two parts of OFDMA symbol are added to form total OFDMA symbol; adding circulated prefixion to system; the base band signal is D / A transformed, then mapped and feedback by emitting antenna. The interference area and adjacent area of the invention can eliminate the interference in the same frequency efficiently and fully, so the communication quality of user in edge of area can be improved.

Description

technical field [0001] The present invention relates to the cellular communication system of Orthogonal Frequency Division Multiplexing (OFDM) technology, such as the third generation mobile communication system, WiMAX, WiBro system etc., particularly relate to the base station transmission signal in the Orthogonal Frequency Division Multiplexing Access (OFDMA) base station Orthogonalization method and system. Background technique [0002] As we all know, in an OFDMA-based cell system, under the premise that the frequency reuse coefficient is 1, each cell, especially the edge area of ​​each cell, will inevitably suffer co-frequency interference from adjacent cells. Therefore, not only the transmission rate of users at the edge of the cell is greatly limited, but also the throughput of the system will be significantly reduced. Therefore, adjacent cell interference is one of the most important factors affecting the performance of the cell system based on OFDM / OFDMA technology...

AI Technical Summary

Problems solved by technology

[0008] In various frequency and time resource scheduling methods, the frequency reuse coefficient cannot really reach 1 or approach 1;

[0009] In addition, for most algorithms, it is necessary to uniformly schedule and manage common frequency and time resources between base stations, which is quite difficult in engineering implementation;

[0010] The cell discrimination algorithm using spreading codes and scrambling codes artificially reduces the information transmission rate. The larger the spreading factor, the greater the reduction in information transmission rate;

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