Differential Relay Cooperative Communication Method Using Quadrature Amplitude Modulation

Abstract

The present invention provides a differential relay cooperative communication method using quadrature amplitude modulation, which mainly solves the problem of poor bit error rate performance under high-order modulation in the prior art. The implementation steps are: (1) Compare the signal-to-noise ratio of the relay link, and select the one with the highest signal-to-noise ratio from multiple relay nodes as the best relay node; (2) The source node first constellates the transmitted information. Mapping and differential modulation, and then send the differentially modulated output signal to the destination node and the best relay node; (3) The best relay node first performs differential demodulation and differential modulation on the received signal, and then converts the differentially modulated The output signal is forwarded to the destination node; (4) The destination node first performs differential demodulation on the transmitted signal of the source node and the transmitted signal of the optimal relay node, and then performs maximum ratio combining on the output signals of the differential demodulation, and finally performs the maximum ratio combination on the maximum Constellation inverse mapping is performed on the combined output signal to obtain the source information. The invention can improve the bit error rate performance of the cooperative communication system.

Description

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AI Technical Summary

Benefits of technology

This patented technique allows two nodes (receiving devices) with different types of wireless networks to communicate effectively together even if they are located far from each other or have poor radio reception capabilities due to factors like obstructions caused during construction work on buildings nearby). By combining these techniques, this new network becomes better at transmitting signals over long distances compared to traditional methods such as DSSS/RDS where multiple copies were sent simultaneously through separate channels.

Problems solved by technology

Technologies like CoMP (Coordinated Multi Point) allow devices called relays collaboratively transmit signals while sharing resource blocks within an area covered by another device called base station. These techniques aimed towards enhancing spatial reuse capacity and reducing interference from nearby sources. While these technologies provide technical benefits they also require coordination among different types of users' access points: radio interfaces, Wireless Access Groups (WAG), etc., making them challenging to achieve even better signal reception capabilities than current methods due to limitations associated with available space division duplex mode operation.

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