Frequency-Time Division based Deep Learning for OFDM Channel Estimation

In this paper, we propose a frequency-time division network (FreqTimeNet) to improve the performance of deep learning (DL) based OFDM channel estimation. This FreqTimeNet is designed based on the orthogonality between the frequency domain and the time domain. In FreqTimeNet, the input signals are processed by parallel frequency blocks first and then go through parallel time blocks. Using 3rd Generation Partnership Project (3GPP) channel models, the mean square error (MSE) performance of FreqTimeNet under different scenarios is evaluated. A method for constructing mixed training data is proposed, which could address the generalization problem in DL. It is observed that FreqTimeNet outperforms other DL networks, with acceptable complexity.