Structure of Deep Neural Networks with a Priori Information in Wireless Tasks

--Deep neural networks (DNNs) have been employed for designing wireless networks in many aspects, such as transceiver optimization, resource allocation, and information prediction. Existing works either use fully-connected DNN or the DNNs with specific structures that are designed in other domains. In this paper, we show that a priori information widely existed in wireless tasks is permutation invariant. For these tasks, we propose a DNN with special structure, where the weight matrices between layers of the DNN only consist of two smaller sub-matrices. By such way of parameter sharing, the number of model parameters reduces, giving rise to low sample and computational complexity for training a DNN. We take predictive resource allocation as an example to show how the designed DNN can be applied for learning the optimal policy with unsupervised learning. Simulations results validate our analysis and show dramatic gain of the proposed structure in terms of reducing training complexity. I NTRODUCTION Deep neural networks (DNNs) have been introduced to design wireless networks recently in various aspects, ranging from signal detection and channel estimation [1], multi-cell coordinated beamforming [2], inter-cell interference management [3], resource allocation [4]-[7], traffic load prediction [8], and uplink/downlink channel calibration [9], etc.