Carrier Frequency Offset Compensation in Wireless Receivers
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Solution Overview
Problem
Conventional methods for estimating and compensating carrier frequency offset (CFO) in wireless communication systems are inadequate, particularly in systems like IEEE 802.15.4q standards, as they fail to accurately compensate CFO within the required range, leading to suboptimal demodulation and synchronization.
Innovation Solution
A method that involves receiving discrete time samples, obtaining a sample vector by dividing sliding vectors into sub-blocks and calculating correlation coefficients, selecting the CFO with the greatest compensation coefficient, and compensating the CFO using tentative estimates and compensation coefficients, expanding the CFO range to meet IEEE 802.15.4q standards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional CFO estimation methods are used, then the system operates within limited CFO range, but it fails to meet IEEE 802.15.4q standards requiring broader compensation range (-250 kHz to +250 kHz)
Solution Approach 1:
The patent divides the received signal into multiple non-overlapping blocks and processes each block separately to generate multiple CFO estimates. This segmentation allows the system to handle broader CFO ranges by combining results from multiple segments, while maintaining accuracy through correlation-based selection of the best estimate.
Solution Approach 2:
The patent implements a feedback mechanism where multiple tentative CFO estimates are generated, each associated with a compensation coefficient indicating its reliability. The system selects the estimate with the greatest compensation coefficient, using this feedback information to ensure accurate CFO compensation across the extended range.
2Adaptability or versatility
If multiple tentative CFO estimates are generated and processed, then broader CFO range is covered, but computational complexity increases
Solution Approach 1:
By dividing the signal into blocks and processing them independently, the patent generates multiple CFO estimates that can cover a broader range. The segmentation approach allows parallel processing of different blocks, managing computational complexity while expanding the compensation range.
Solution Approach 2:
The patent changes the parameter of signal block size and number of segments to optimize the balance between coverage range and computational complexity. By adjusting these parameters, the system can adapt to different CFO scenarios while maintaining manageable processing requirements.
Data Source
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AI summary
A method to compensate a carrier frequency offset (CFO) in a receiver is disclosed. The method includes receiving discrete time samples, obtaining a sample vector from the received discrete time samples, obtaining tentative CFO estimates based on the sample vector, selecting a CFO having a greatest compensation coefficient from the tentative CFO estimates, and compensating the CFO in the received discrete time samples.