Communication modulation signal recognition based on the deep multi-hop neural network.

• The multi-hop connection rate improve the transmission efficiency of the signal features learned by the multi-hop network. • The receptive field extension scope determines how many extracted features in each layer are used for the final results. • In the experiment, the diverse signal lengths are contrasted and analyzed by the public and real signal dataset. Automatic modulation classification (AMC) is one of the core technologies in non-cooperative communication. In the complex wireless environment, it is not easy to quickly and accurately recognize the modulation styles of signals by conventional methods. The deep learning method (DLM) can deal with the problem and achieve good effects. In conventional DLMs, the length of input data is fixed. However, the signal length in communication is changing, which may not make full use of the DLMs' input signal information to improve the recognition accuracy. In this paper, the deep multi-hop convolutional neural network (CNN) is employed to learn the time-domain signal features with different lengths. The proposed network includes the multi-hop connection rate and the receptive field extension scope to dispose of the limitation. The experiment shows that the proposed network can achieve better recognition results under the sparse multi-hop network structure. The reception field extension scope is also conducive to further improve the recognition effects. Finally, the proposed network has shorter training time and smaller parameters, which is more convenient for training the network and deploying in the existing communication system. [ABSTRACT FROM AUTHOR]