【1】Xin Fan, Yue Wang, Yan Huo, Zhi Tian. Communication-efficient Federated Learning Through 1-Bit Compressive Sensing and Analog Aggregation[C] //2021 IEEE International Conference on Communications (IEEE ICC 2021) . IEEE, 2021: 1-6 （清华B类，CCF C类，北交大A类）

Abstract:

This paper studies communication-efficient federated learning (FL) over the air, which is based on 1-bit compressive sensing (CS) and analog aggregation transmissions. To analyze the impact of these two communication efficiency oriented technologies on FL, we derive a closed-form expression for the expected convergence rate of the FL algorithm. Our theoretical result implies that the communication efficiency comes at the expense of the performance degradation due to the aggregation errors caused by sparsification, dimension reduction, quantization, signal reconstruction and noise. Then, we formulate a joint optimization problem to mitigate the impact of these aggregation errors on FL by an optimal scheduling and power scaling policy. An enumerated method is proposed to solve this non-convex problem, which is optimal but becomes computationally infeasible as the number of devices increases. Hence, we further propose a suboptimal solution based on the alternating direction method of multiplier to reduce the complexity when applied in large-scale networks. Simulation results show that our proposed 1-bit CS based FL over the air achieves comparable performance to the ideal case where conventional FL without compression and quantification is applied over error-free aggregation, at much reduced communication overhead and transmission latency.

【2】Xin Fan, Yue Wang, Guangkai Li, Yan Huo, Zhi Tian. Hybrid Uplink-Downlink NOMA for Secure Coordinated Multi-Point Networks[C] //2021 IEEE International Conference on Communications (IEEE ICC 2021),1-6. IEEE, 2021: 1-6 （清华B类，CCF C类，北交大A类）

Abstract:

In this paper, we propose a novel hybrid uplink-downlink non-orthogonal multiple access scheme (HUD-NOMA) for coordinated multi-point (CoMP) networks. By using NOMA technology and network coding for effective interference control, the proposed HUD-NOMA scheme improves the transmission rate of edge users. Although there is a slight decrease in signal reception reliability to the users with strong received signals, the sum rate of the whole system is increased. Since the intended interferences are effectively manageable by the legitimate users, the HUD-NOMA scheme is resistant to eavesdroppers. Then, by using a stochastic geometry approach, we further analyze the secrecy outage probability (SOP) of the CoMP network applying the proposed HUD-NOMA. Numerical results verify that our scheme outperforms the existing method in terms of higher transmission rates and lower SOP.