Multi-dimensional Signal Encoding via Transpositional Modulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional signal modulation techniques are limited in data transmission capacity, as they operate primarily in two-dimensional constellations, which restricts the number of bits that can be represented and the data rate of signals.
Innovation Solution
The implementation of a multi-dimensional symbol constellation that incorporates transpositional modulation (TM) alongside traditional quadrature amplitude modulation (QAM), allowing for additional dimensions to carry information, thereby increasing data transmission rates and throughput.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If traditional two-dimensional QAM modulation is used, then the modulation scheme is simple and easy to implement, but the data transmission capacity is limited
Solution Approach 1:
The patent applies dimensionality change by extending the traditional two-dimensional QAM constellation to three or more dimensions. The third dimension is created using transpositional modulation (TM) which modulates a harmonic of the carrier signal. This allows data to be encoded across multiple dimensions (I, Q, and TM), significantly increasing the number of bits that can be represented per symbol while maintaining compatibility with existing two-dimensional demodulation systems.
2Productivity
If multi-dimensional constellation with TM signal is used, then the data rate increases significantly, but the signal processing complexity increases
Solution Approach 1:
The patent segments the modulation process into independent two-dimensional QAM modulation and transpositional modulation components. The QAM signal and TM signal are generated separately and then combined, allowing each component to be processed independently. This segmentation enables the system to achieve high data rates through multi-dimensional constellations while managing processing complexity by maintaining separate processing paths for each modulation type.
Solution Approach 2:
The patent creates a universal modulation scheme that can operate in multiple modes: traditional two-dimensional QAM for legacy compatibility, and extended multi-dimensional QAM-TM for high data rate applications. The system can adaptively select the appropriate constellation dimensionality based on channel conditions and receiver capabilities, providing multi-functionality that balances data rate requirements with processing complexity constraints.
Data Source
AI summary
Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for communicating signals using a multi-dimensional symbol constellation. In one example, a process for modulating a carrier signal includes the actions of mapping data to symbols of a multi-dimensional symbol constellation that includes at least three dimensions, each dimension of the constellation represented by a respective modulation signal. The dimensions of the constellation include first and second dimensions each of which are represented by respective in-phase modulation values and quadrature phase modulation values of a quadrature amplitude modulation (QAM) signal, and a third dimension represented by a transpositional modulation (TM) signal. The method further includes modulating a carrier signal with the TM signal and the QAM signal.