郭子钰老师四篇合作论文分别在IEEE Transactions on Circuits and Systems、IEEE Transactions on Intelligent Transportation Systems和IEEE Signal Processing Letters上发表

· 第一篇论文题为An Energy-Efficient BNN Accelerator With Two-Stage Value Prediction for Sparse-Edge Gesture Recognition，发表在IEEE Transactions on Circuits and Systems I: Regular Papers上。

论文摘要：In recent years, natural, flexible, and contactless vision-based gesture recognition has received significant attention in human-computer interaction. However, employing convolutional neural networks (CNNs) for RGB or RGB-D gestures can result in excessive power consumption and poor energy efficiency, making them unsuitable for embedded systems. In this paper, we propose a lightweight sparse binarized neural network (sBNN) model for edge gesture recognition that achieves an accuracy of 89.43%-99.92% on four open-source gesture datasets with ≤20.26 million operations (MOP) and ≤15.83 -Kilobytes (KB) parameters. We find high channel-level sparsity in the activation maps of sBNN when edge gestures are used as inputs. The sparse activation maps have multiple identical activation vectors called sparse activation vectors (SAV), which lead to highly repeated calculations. In order to avoid this issue, we propose a two-stage value prediction approach to skip these calculations, achieving a speedup of 1.03x-1.83x. Moreover, to reduce on- chip memory, the compression technique is applied to the sparse activation maps, providing a compression rate of 1.72x-3.45x. Finally, we implement an energy-efficient sparse BNN accelerator (SBA) on an embedded field-programmable gate array (FPGA). The experimental results show that our SBA has a latency of 26.3-46.8- μs , a power consumption of 0.807 W, and an energy efficiency of 536.22-952.70-GOPS/W at 50-MHz frequency. Our SBA offers lower latency, lower power consumption, and higher energy efficiency than previous state-of-the-art gesture recognition accelerators.

论文作者：Yongliang Zhang; Yitong Rong; Xuyang Duan; Zhen Yang; Qiang Li; Ziyu Guo; Xu Cheng; Xiaoyang Zeng; Jun Han

· 第二篇论文题为A RIS-Based Vehicle DOA Estimation Method With Integrated Sensing and Communication System，发表在IEEE Transactions on Intelligent Transportation Systems上。

论文摘要：With the development of intelligent transportation, growing attention has been received to integrated sensing and communication (ISAC) systems. In this paper, we formulate a novel passive sensing technique to obtain information on the vehicle’s direction of arrival (DOA) using reconfigurable intelligent surfaces (RIS). A novel estimation method is proposed in the scenario with a receiver using only one full-functional channel, where multiple measurements for the DOA estimation are achieved by controlling the reflection matrix (measurement matrix) in the RIS. Moreover, different from the existing estimation methods, we also consider the interference signals introduced by wireless communication in the ISAC system. Then, we propose a novel atomic norm-based method to remove the interference signals and reconstruct the sparse signal. Additionally, a novel Hankel-based multiple signal classification (MUSIC) method is formulated to obtain the DOA information after the interference removal. To reduce the interference signals more efficiently and improve the performance of the sparse reconstruction, we optimize the measurement matrix to improve the signal-to-interference-plus-noise ratio (SINR). Finally, the theoretical Cram’er-Rao lower bound (CRLB) is derived for the ISAC system on the vehicle DOA estimation. Simulation results show that the proposed method can achieve better performance in the DOA estimation, and the corresponding CRLB with different distributions of the sensing nodes are shown. The code for the proposed method is available online https://github.com/chenpengseu/PassiveDOA-ISAC-RIS.git.

论文作者：Zhimin Chen; Peng Chen; Ziyu Guo; Yudong Zhang; Xianbin Wang

· 第三篇论文题为Low-Cost Beamforming and DOA Estimation Based on One-Bit Reconfigurable Intelligent Surface，发表在IEEE Signal Processing Letters上。

论文摘要：In this work, we consider the Direction-of-Arrival (DOA) estimation problem in a low-cost architecture where only one antenna as the receiver is aided by a reconfigurable intelligent surface (RIS). We introduce the one-bit RIS as a signal reflector to enhance signal transmission in non-line-of-sight (NLOS) situations and substantially simplify the physical hardware for DOA estimation. We optimize the beamforming scheme called measurement matrix to focus the echo power on the receiver with the coarse localization information of the targets as the prior. A beamforming scheme based on the modified genetic algorithm is proposed to optimize the measurement matrix, guaranteeing restricted isometry property (RIP) and meeting single beamforming requirements. The DOA results are finely estimated by solving an atomic-norm based sparse reconstruction problem. Simulation results show that the proposed method outperforms the existing methods in the DOA estimation performance.

论文作者：Zihan Yang; Peng Chen; Ziyu Guo; Dahai Ni

· 第四篇论文题为Reconfigurable Intelligent Surface Aided Sparse DOA Estimation Method With Non-ULA，发表在IEEE Signal Processing Letters上。

论文摘要：The direction of arrival (DOA) estimation problem is addressed in this letter. A reconfigurable intelligent surface (RIS) aided system for the DOA estimation is proposed. Unlike traditional DOA estimation systems, a low-cost system with only one complete functional receiver is given by changing the phases of the reflected signals at the RIS elements to realize the multiple measurements. Moreover, an atomic norm-based method is proposed for the DOA estimation by exploiting the target sparsity in the spatial domain and solved by a semi-definite programming (SDP) method. Furthermore, the RIS elements can be any geometry array for practical consideration, so a transformation matrix is formulated and different from the conventional SDP method. Simulation results show that the proposed method can estimate the DOA more accurately than the existing methods in the non-uniform linear RIS array.

论文作者：Peng Chen; Zihan Yang; Zhimin Chen; Ziyu Guo