Journals / Celal Bayar Üniversitesi Fen Bilimleri Dergisi / 2026 / Cilt: 22 Sayı: 1

Enhancing OFDM Channel Estimation Accuracy with CNN-LSTM Hybrid Architectures

Sekou J. Massalay(MANISA CELAL BAYAR UNIVERSITY)0009-0002-3372-4411
İlhan Baştürk(MANISA CELAL BAYAR UNIVERSITY)0000-0003-1869-6010
Yücel Koçyiğit(MANISA CELAL BAYAR UNIVERSITY)0000-0003-1785-198X
Pages
86–94
Publication Date
2026-03-30
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

The results confirm that the hybrid architecture provides a scalable and reliable solution for future wireless systems including sixth-generation (6G) networks, vehicular communications, and satellite applications where both adaptability and robustness are essential.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:Accurate channel estimation remains a fundamental challenge for next-generation orthogonal frequency-division multiplexing (OFDM) systems, especially in environments with high mobility, sparse pilot allocation, and time-varying multipath fading.
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Key Findings & Data:This study introduces a pilot-grid-aware hybrid deep learning model that integrates Convolutional Neural Networks (CNNs) for spatial feature extraction with Long Short-Term Memory (LSTM) networks for temporal sequence modeling.
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Conclusion & Impact:The results confirm that the hybrid architecture provides a scalable and reliable solution for future wireless systems including sixth-generation (6G) networks, vehicular communications, and satellite applications where both adaptability and robustness are essential.
🔬Design:Modeling & Simulation
📍Scope:Comprehensive Sample
⚙️Variables:Channel Estimation · Deep Learning · Hybrid CNN-LSTM

Abstract

Accurate channel estimation remains a fundamental challenge for next-generation orthogonal frequency-division multiplexing (OFDM) systems, especially in environments with high mobility, sparse pilot allocation, and time-varying multipath fading. Traditional pilot-based methods, such as Least Squares (LS) and Minimum Mean Square Error (MMSE), are easy to implement but suffer from noise sensitivity, high computational costs, and a reliance on prior channel statistics. Recently, deep learning techniques have shown promising results; yet many do not fully capture the joint spatial and temporal characteristics of wireless channels or overlook realistic pilot-grid structures. This study introduces a pilot-grid-aware hybrid deep learning model that integrates Convolutional Neural Networks (CNNs) for spatial feature extraction with Long Short-Term Memory (LSTM) networks for temporal sequence modeling. The model is trained using the Root Mean Square Propagation (RMSprop) optimizer, selected for its robustness in adapting learning rates and effectively capturing dependencies across both spatial and temporal dimensions. Benchmark evaluations against conventional estimators and theoretical limits under different modulation formats demonstrate that the proposed model consistently achieves a lower estimation error and bit error rate across a wide range of signal-to-noise ratios. The results confirm that the hybrid architecture provides a scalable and reliable solution for future wireless systems including sixth-generation (6G) networks, vehicular communications, and satellite applications where both adaptability and robustness are essential.

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Cite This Article

Massalay, S. J., Baştürk, İ., Koçyiğit, Y. (2026). Enhancing OFDM Channel Estimation Accuracy with CNN-LSTM Hybrid Architectures. Celal Bayar Üniversitesi Fen Bilimleri Dergisi, Cilt: 22 Sayı: 1, 86–94. https://doi.org/10.18466/cbayarfbe.1773106

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