Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation（CFNCC...Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation（CFNCC） scheme based on multi-user detection for the multiple unicast transmission is proposed.Theoretic analysis and simulation results demonstrate that,compared with the conventional cooperation（CC） scheme and network-coded cooperation（NCC） scheme,CFNCC would obtain higher network throughput and consumes less time slots.Moreover,a further investigation is made for the symbol error probability（SEP） performance of CFNCC scheme,and SEPs of CFNCC scheme are compared with those of NCC scheme in various scenarios for different signal to noise ratio（SNR） values.展开更多
Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework ...Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework with parallel interference cancellation, a supervision decision algorithm based on pre-decision of probabilistic data association (PDA) and hard decision is proposed. The detection performance is analyzed and simulation is implemented to show that the supervision decision algorithm improves the detection performance effectively.展开更多
Continuous and stable tracking of the ground maneuvering target is a challenging problem due to the complex terrain and high clutter. A collaborative tracking method of the multisensor network is presented for the gro...Continuous and stable tracking of the ground maneuvering target is a challenging problem due to the complex terrain and high clutter. A collaborative tracking method of the multisensor network is presented for the ground maneuvering target in the presence of the detection blind zone(DBZ). First, the sensor scheduling process is modeled within the partially observable Markov decision process(POMDP) framework. To evaluate the target tracking accuracy of the sensor, the Fisher information is applied to constructing the reward function. The key of the proposed scheduling method is forecasting and early decisionmaking. Thus, an approximate method based on unscented sampling is presented to estimate the target state and the multi-step scheduling reward over the prediction time horizon. Moreover, the problem is converted into a nonlinear optimization problem, and a fast search algorithm is given to solve the sensor scheduling scheme quickly. Simulation results demonstrate the proposed nonmyopic scheduling method(Non-MSM) has a better target tracking accuracy compared with traditional methods.展开更多
针对户外导盲场景中道路目标检测存在的复杂背景干扰及关键语义信息需求,当前目标检测算法在道路目标检测中表现出较低的准确性以及容易出现漏检的问题,为此提出一种基于YOLOv8n的道路目标检测算法OD-YOLO。基于FasterNet和SPPF构建主...针对户外导盲场景中道路目标检测存在的复杂背景干扰及关键语义信息需求,当前目标检测算法在道路目标检测中表现出较低的准确性以及容易出现漏检的问题,为此提出一种基于YOLOv8n的道路目标检测算法OD-YOLO。基于FasterNet和SPPF构建主干网络;使用FasterNet以增强特征提取能力,在SPPF模块中引入可分离大核注意力机制(large separable kernel attention,LSKA)以提高算法对道路目标整体的感知能力。提出一种新的C2f模块GAC2f,在减小模型计算量的同时提高其特征捕获能力,同时通过使用多样分支模块(diverse branch block,DBB)中结构重参数化思想优化GAC2f,在不损失模型性能的前提下,融合多种特征信息以显著提高模型精度,另一方面使用卷积门控线性单元(convolutional gated linear unit,Convolutional GLU)改进LarK中的大核卷积以优化GAC2f,使模型能够捕获更多上下文信息。提出一种轻量级非对称检测头PADH,在提高模型性能的同时减少参数量,并使用PIoUv2改进原有的损失函数,通过基于层自适应稀疏度的量级剪枝(layer-adaptive sparsity for the magnitude-based pruning,LAMP)操作进一步优化算法模型。实验结果表明,在公共人行道路目标数据集WOTR上,OD-YOLO与YOLOv8n相比,经过剪枝后模型参数量同为3×10^(6),但mAP@0.5、mAP@0.5:0.95分别提升3.4和4.1个百分点,证明算法OD-YOLO在面向户外导盲场景的道路目标检测中可以达到预期的效果。展开更多
基金supported by the National Natural Science Foundation of China(6104000561001126+5 种基金61271262)the China Postdoctoral Science Foundation Funded Project(201104916382012T50789)the Natural Science Foundation of Shannxi Province of China(2011JQ8036)the Special Fund for Basic Scientific Research of Central Colleges (CHD2012ZD005)the Research Fund of Zhejiang University of Technology(20100244)
文摘Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation（CFNCC） scheme based on multi-user detection for the multiple unicast transmission is proposed.Theoretic analysis and simulation results demonstrate that,compared with the conventional cooperation（CC） scheme and network-coded cooperation（NCC） scheme,CFNCC would obtain higher network throughput and consumes less time slots.Moreover,a further investigation is made for the symbol error probability（SEP） performance of CFNCC scheme,and SEPs of CFNCC scheme are compared with those of NCC scheme in various scenarios for different signal to noise ratio（SNR） values.
文摘Multi-user detection (MUD) based on multirate transmission in code division multiple access (CDMA) system is discussed. Under the requirement of signal interference ratio (SIR) detection at base station and framework with parallel interference cancellation, a supervision decision algorithm based on pre-decision of probabilistic data association (PDA) and hard decision is proposed. The detection performance is analyzed and simulation is implemented to show that the supervision decision algorithm improves the detection performance effectively.
基金supported by the National Defense Pre-Research Foundation of China(0102015012600A2203)。
文摘Continuous and stable tracking of the ground maneuvering target is a challenging problem due to the complex terrain and high clutter. A collaborative tracking method of the multisensor network is presented for the ground maneuvering target in the presence of the detection blind zone(DBZ). First, the sensor scheduling process is modeled within the partially observable Markov decision process(POMDP) framework. To evaluate the target tracking accuracy of the sensor, the Fisher information is applied to constructing the reward function. The key of the proposed scheduling method is forecasting and early decisionmaking. Thus, an approximate method based on unscented sampling is presented to estimate the target state and the multi-step scheduling reward over the prediction time horizon. Moreover, the problem is converted into a nonlinear optimization problem, and a fast search algorithm is given to solve the sensor scheduling scheme quickly. Simulation results demonstrate the proposed nonmyopic scheduling method(Non-MSM) has a better target tracking accuracy compared with traditional methods.
文摘针对户外导盲场景中道路目标检测存在的复杂背景干扰及关键语义信息需求,当前目标检测算法在道路目标检测中表现出较低的准确性以及容易出现漏检的问题,为此提出一种基于YOLOv8n的道路目标检测算法OD-YOLO。基于FasterNet和SPPF构建主干网络;使用FasterNet以增强特征提取能力,在SPPF模块中引入可分离大核注意力机制(large separable kernel attention,LSKA)以提高算法对道路目标整体的感知能力。提出一种新的C2f模块GAC2f,在减小模型计算量的同时提高其特征捕获能力,同时通过使用多样分支模块(diverse branch block,DBB)中结构重参数化思想优化GAC2f,在不损失模型性能的前提下,融合多种特征信息以显著提高模型精度,另一方面使用卷积门控线性单元(convolutional gated linear unit,Convolutional GLU)改进LarK中的大核卷积以优化GAC2f,使模型能够捕获更多上下文信息。提出一种轻量级非对称检测头PADH,在提高模型性能的同时减少参数量,并使用PIoUv2改进原有的损失函数,通过基于层自适应稀疏度的量级剪枝(layer-adaptive sparsity for the magnitude-based pruning,LAMP)操作进一步优化算法模型。实验结果表明,在公共人行道路目标数据集WOTR上,OD-YOLO与YOLOv8n相比,经过剪枝后模型参数量同为3×10^(6),但mAP@0.5、mAP@0.5:0.95分别提升3.4和4.1个百分点,证明算法OD-YOLO在面向户外导盲场景的道路目标检测中可以达到预期的效果。
