Sparsity-adaptive equalization for mmWave MU-MIMO
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Millimeter wave (mmWave) massive MU-MIMO systems face challenges in reducing hardware complexity and power consumption due to high propagation losses and the need for fine-grained beamforming, especially with all-digital architectures, which often result in performance degradation and increased preprocessing complexity.
Innovation Solution
A sparsity-adaptive equalization system, known as SPADE, that adaptively disables multiplier circuits based on threshold values for the input signals and weighting values, reducing the number of multiplications required for spatial equalization and thereby lowering power consumption and implementation complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If all-digital architectures with low-resolution data converters are used, then spectral efficiency is improved and RF circuitry is simplified, but baseband processing complexity and power consumption increase
Solution Approach 1:
The patent extracts and exploits the sparsity property inherent in mmWave channels to separate significant multiplications from negligible ones. By identifying and removing redundant multiplications (those involving near-zero channel coefficients), the system reduces baseband processing complexity while preserving spectral efficiency benefits.
Solution Approach 2:
The patent changes the processing parameter from fixed full-precision multiplication to adaptive sparsity-aware multiplication. By dynamically adjusting the number of multiplications based on channel sparsity characteristics, the system reduces computational complexity while maintaining performance.
2Reliability
If the number of base station antennas is increased for fine-grained beamforming, then propagation losses are compensated, but hardware complexity increases
Solution Approach 1:
The patent extracts only the essential multiplications needed for effective beamforming by identifying non-negligible channel coefficients. This reduces the number of active multiplier circuits while maintaining the beamforming capability needed to compensate for propagation losses.
Solution Approach 2:
The patent applies different processing quality to different antenna elements based on their channel coefficient magnitudes. High-priority multiplications involve significant coefficients, while low-priority ones involve near-zero coefficients that can be skipped, creating local quality differentiation in processing.
3Reliability
If conventional equalization algorithms are used, then equalization performance is maintained, but power consumption increases due to excessive multiplications
Solution Approach 1:
The patent extracts and eliminates redundant multiplications by detecting near-zero channel coefficients. This reduces the number of active multiplier circuits and associated power consumption while preserving equalization performance through the remaining essential multiplications.
Solution Approach 2:
The patent applies partial action by performing only the necessary multiplications rather than all possible multiplications. By executing a subset of multiplications (those with significant coefficients) and skipping others (those with near-zero coefficients), the system reduces power consumption while maintaining adequate equalization performance.
Data Source
AI summary
A wireless communication system can include an antenna and an equalization system. The antenna can be configured to wirelessly receive a data signal from a user equipment (UE). The equalization system can be configured to compensate for distortion incurred by the data signal during propagation. The equalization system can include a set of multiplier circuits. Each multiplier circuit can include a first input, a second input, a multiplier device, and a management circuit. The first input can receive a first input signal that corresponds to the data signal. The second input can receive a second input signal that corresponds to a weighting value assigned to a channel associated with the antenna. The multiplier device can be enabled or disabled. When enabled, the multiplier device can be configured to perform a multiplication operation on the first input signal and the second input signal. When disabled, the multiplier circuit may not perform the multiplication operation. The management circuit can be configured to selectively disable or enable the multiplier device based on the first input signal and/or the second input signal, thereby reducing an effective number of multiplications and offering power savings.