Wireless Device Phase Compensation Spatial Multiplexing
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Solution Overview
Problem
Conventional phase tracking circuits face efficiency losses and complexity when dealing with spatial-multiplexed pilot subcarriers in wireless communication systems, as they either reduce transmission efficiency by demultiplexing in time or frequency domains or require complex inverse matrix operations for phase compensation.
Innovation Solution
A wireless communication apparatus that generates a spatial-multiplex pilot subcarrier reference signal, extracts the spatial-multiplex pilot subcarrier from received signals, and compensates for phase differences using a phase compensating section comparing the reference signal with the extracted pilot subcarrier signal, allowing phase difference detection and compensation without dedicated demultiplexing circuits.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional phase tracking circuits demultiplex spatial-multiplexed pilot subcarriers in time or frequency domains, then phase compensation can be performed, but transmission efficiency is reduced
Solution Approach 1:
The invention extracts only the necessary pilot subcarrier components from the spatial-multiplexed signal without performing full demultiplexing operations. By selectively extracting pilot subcarriers and comparing them with reference signals, the system achieves phase compensation while avoiding the transmission efficiency loss associated with complete demultiplexing of spatial-multiplexed signals.
2Measurement precision
If conventional phase tracking circuits perform inverse matrix operations for phase compensation of spatial-multiplexed pilot subcarriers, then phase accuracy is improved, but device complexity increases
Solution Approach 1:
The invention creates a reference signal that is a copy of the expected pilot subcarrier signal, knowing in advance the structure and positioning of pilot subcarriers in spatial-multiplexed transmission. By comparing the received pilot subcarriers with this pre-prepared reference signal, the system achieves phase detection without requiring complex inverse matrix operations or dedicated demultiplexing circuits.
3Productivity
If spatial-multiplexing transmission is used to increase communication capacity, then data transmission rate is improved, but phase rotation due to residual carrier frequency difference and phase noise becomes more significant
Solution Approach 1:
The invention implements a feedback mechanism where the phase difference detected from pilot subcarriers is used to generate phase compensation values, which are then applied to correct the received signals. This closed-loop approach continuously monitors and corrects phase rotation caused by residual carrier frequency differences and phase noise, maintaining phase stability in spatial-multiplexing transmission systems.
Data Source
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AI summary
A wireless communication device (1) comprises a spatially-multiplexed PSC extracting section (8) for extracting a spatially multiplexed known pilot subcarrier signal (S5) from the received multicarrier-modulated signal, a reference signal generating section (7) for generating a reference signal (S4) of the spatially-multiplexed pilot subcarrier signal, and a phase compensating section (9) for compensating the phase difference of the received signal (S1) according to the pilot subcarrier signal (S5) extracted by the spatially-multiplexed pilot subcarrier extracting section (8) and the reference signal (S4). Therefore, even if a pilot subcarrier signal is spatiallymultiplexed and transmitted, phase difference detection and phase compensation can be performed by a simple constitution.