Non-Orthogonal Multiple Access Transmission Mode Selection
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Solution Overview
Problem
Current 5G communication systems face challenges in achieving high channel capacity and efficient signal transmission, particularly in multi-antenna environments with varying signal-to-interference and noise ratios, where existing research has not effectively utilized diversity gain and power allocation methods to improve performance for terminals with different channel conditions.
Innovation Solution
The proposed solution involves determining the optimal transmission mode among multiple modes based on channel information from terminals, using a combination of diversity and multiplexing schemes in a non-orthogonal multiple access (NOMA) system, where power allocation is adjusted to maximize channel capacity, and signals are transmitted using space-time block coding and superposition coding techniques.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional orthogonal multiple access is used, then interference between terminals is reduced, but channel capacity and spectral efficiency are limited
Solution Approach 1:
The patent changes the orthogonality parameter of multiple access from orthogonal to non-orthogonal, allowing terminals to share the same time-frequency resources. This parameter change enables higher channel capacity and spectral efficiency while managing interference through power domain separation and successive interference cancellation techniques
Solution Approach 2:
The patent introduces a new dimension for resource separation by moving from spatial orthogonality to power domain separation. Terminals are separated not by orthogonal resources but by different power levels, enabling multiple access in the power dimension while maintaining resource efficiency
2Reliability
If power allocation is increased to improve signal quality for cell boundary terminals, then bit error rate performance improves, but overall system power efficiency deteriorates
Solution Approach 1:
The patent applies different power allocation strategies to different terminals based on their channel conditions. Cell boundary terminals receive higher power allocation to improve their bit error rate performance, while terminals with better channel conditions receive lower power, optimizing overall power efficiency through localized quality adjustment
Solution Approach 2:
The power allocation is dynamically adjusted based on real-time channel state information and terminal locations. The system continuously adapts power distribution to maintain reliable communication for cell boundary terminals while minimizing overall power consumption through successive interference cancellation and adaptive modulation
3Reliability
If diversity schemes are applied to all terminals, then reliability improves, but system complexity and overhead increase
Solution Approach 1:
The patent applies diversity schemes selectively to terminals based on their channel conditions and locations. Cell boundary terminals with poor channel conditions receive diversity treatment to improve reliability, while terminals with good channel conditions use simpler transmission modes, reducing overall system complexity
Solution Approach 2:
Instead of applying diversity schemes to all terminals, the patent applies them partially only to terminals that benefit most from diversity gain. This partial action approach maintains reliability for vulnerable terminals while avoiding unnecessary complexity in the overall system
Data Source
AI summary
The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4th-Generation (4G) communication system such as Long Term Evolution (LTE). According to various embodiments in the present disclosure, an operating method of a base station in a wireless communication system may include determining a transmission mode of the greatest channel capacity among a plurality of transmission modes based on first channel information of a first terminal and second channel information of a second terminal, and transmitting a transmit signal generated based on the determined transmission mode to the first terminal and the second terminal. The first transmission mode of the plurality of the transmission modes may be a transmission mode for applying a diversity scheme to a first signal for the first terminal, applying a multiplexing scheme to a second signal for the second terminal, and transmitting the transmit signal comprising the first signal and the second signal in a non-orthogonal multiple access (NOMA) scheme.