arXiv AI By Hee-Yang Jung, Dong-Hee Paek, Woo-Jin Jung, Seung-Hyun Kong

Frequency Estimation Based on SNR-adaptive Frequency Estimator Under Wide SNR Range

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The paper introduces SAFE, an SNR‑adaptive frequency estimator that combines a time‑frequency image neural network (TFINet) to enhance weak tone components at low SNR with an SNR‑based frequency selector (SFS) that chooses the appropriate estimator for each tone. SAFE achieves a 13.00% false negative rate across –10 dB to 0 dB SNR, improving over state‑of‑the‑art methods by 13.04% and reducing nearest‑neighbor RMSE by 56.67%. Real‑world experiments confirm its robustness in cluttered environments.

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