Non-linear filter demodulator for carrier frequency offset correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solutions for carrier frequency offset (CFO) estimation in low-power wireless sensor and actor networks (LP-WSAN) are complex, leading to increased power consumption and latency, and often require separate coarse-grain and fine-grain estimation processes.
Innovation Solution
A wireless device with a non-linear filter demodulator and signal parameter acquisition unit that jointly performs coarse-grain CFO estimation and correction, reducing latency and power consumption, and optionally includes fine-grain estimation for more sensitive applications, allowing for adaptive performance configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If existing complex algorithms are used for CFO estimation, then measurement precision is improved, but use of energy increases and loss of time increases
Solution Approach 1:
The patent merges CFO estimation with the demodulation process by integrating a CFO estimator within the non-linear filter demodulator. This allows simultaneous execution of demodulation and CFO estimation using shared computational resources and received signal data, eliminating the need for separate complex estimation algorithms and reducing overall power consumption while maintaining precision.
Solution Approach 2:
The non-linear filter demodulator is designed to perform multiple functions: it simultaneously executes demodulation and CFO estimation. By making the demodulator universal, the system avoids dedicating separate high-power processing units solely for CFO estimation, thereby reducing energy usage while preserving measurement precision through the same sophisticated filtering mechanisms.
2Measurement precision
If existing complex algorithms are used for CFO estimation, then measurement precision is improved, but loss of time increases
Solution Approach 1:
By combining CFO estimation with demodulation in a single integrated process, the patent eliminates sequential execution delays. The CFO estimator operates concurrently with the demodulator using the same input signal and computational pipeline, significantly reducing latency while maintaining estimation precision through the robust non-linear filtering approach.
3Measurement precision
If separate coarse-grain and fine-grain estimation processes are used, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent merges both coarse-grain and fine-grain estimation functionalities into a single integrated CFO estimator within the non-linear filter demodulator. The estimator automatically adapts its operation based on signal conditions, performing both levels of estimation simultaneously or sequentially as needed, thereby achieving high precision without requiring separate independent processing blocks or complex external control logic.
Data Source
AI summary
A wireless device, and corresponding method, having a receiver configured to receive a signal having in-phase and quadrature components; a non-linear filter demodulator configured to translate noncoherently the in-phase and quadrature components into phase and frequency domain signals, and to estimate and correct carrier frequency offset; a coherence signal parameter acquisition unit is configured to estimate and correct at least one correct coherence signal parameter based on the in-phase and quadrature components and the phase or frequency domain signal; and a symbol detector is configured to detect information in the phase or frequency domain signal. If optimal coherent information detection is desired, the at least one signal parameter is not only carrier phase offset and carrier timing offset, but also phase frequency offset, wherein the estimation and correction of the carrier frequency offset performed by the signal parameter acquisition unit is more precise than that performed by the non-linear filter demodulator. In such a case the detector is configured to detect information in the phase domain signal.