Interference Alignment Using Lattice Constellation and Beamforming
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Solution Overview
Problem
Existing interference alignment methods in multi-channel communication systems face challenges in achieving optimal performance due to the requirement that all interference signals must be aligned in the same direction, which reduces the signal-to-noise ratio and makes it difficult to implement effectively, especially in systems with more than two users.
Innovation Solution
The method combines lattice construction and beamforming techniques for interference alignment, where precoding vectors and receive vectors are determined to align interference signals in a manner that forms a lattice constellation pattern at the receiver, effectively canceling interference and maintaining signal strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If interference signals are aligned in the same direction at the receiver, then interference alignment is achieved, but the signal-to-noise ratio of desired signals becomes lower
Solution Approach 1:
The patent segments the interference alignment approach into two distinct methods: lattice construction method for aligning interference signals in multi-dimensional space, and beamforming method for directional interference suppression. This segmentation allows each method to address specific aspects of interference management without compromising signal quality.
Solution Approach 2:
The patent extends interference alignment from traditional two-dimensional spatial alignment to multi-dimensional alignment by incorporating lattice construction in complex signal space. This dimensionality expansion allows interference signals to be aligned in directions orthogonal to desired signals, preventing signal-to-noise ratio degradation.
2Reliability
If interference alignment is implemented using lattice construction method, then interference signals form a lattice constellation pattern, but it is difficult to implement in interference channels with more than two users
Solution Approach 1:
The patent develops a universal interference alignment framework that combines lattice construction and beamforming methods, making the system adaptable to interference channels with any number of users. The beamforming component provides directional interference suppression that works effectively in multi-user scenarios where pure lattice construction becomes computationally intractable.
Solution Approach 2:
The patent introduces dynamic adaptation between lattice construction and beamforming methods based on channel conditions and user configuration. The system dynamically adjusts the proportion and combination of these two methods to optimize performance for the current operational context, enabling scalability from two-user to multi-user interference channels.
3Object-generated harmful factors
If interference signals are aligned close to desired signals in space direction, then interference can be canceled at the receiver, but the power of desired signals becomes smaller
Solution Approach 1:
The patent employs beamforming as a counterweight mechanism that creates directional interference suppression while preserving desired signal power. The beamforming vectors are designed to null interference directions without attenuating the directions of desired signals, effectively counterbalancing the power loss that would occur with conventional interference alignment.
Data Source
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AI summary
The present invention provides an interference alignment method and device and a multi-channel communication system. The method includes: obtaining channel matrix in a multi-channel communication system; determining a first desired signal and a second desired signal of the multi-channel communication system according to the channel matrix; obtaining precoding vectors and receive vectors, so that at a receiver corresponding to the first desired signal, after a first receive signal is filtered by a receive vector corresponding to the first desired signal, a signal formed by superposing interference signals included therein has a feature of a lattice constellation pattern, and that at a receiver corresponding to the second desired signal, after a second receive signal is filtered by a receive vector corresponding to the second desired signal, interference signals included therein are canceled, where the first receive signal and the second receive signal are transmit signals sent to the corresponding receivers after precoding processing is performed at transmitters by using corresponding precoding vectors. Embodiments of the present invention may improve the system performance in interference alignment.