In radio receivers,complete implementation of the software defined radio(SDR) concept is mainly limited by frontend.Based on bandpass sampling(BPS) theory,a flexible digital frontend(DFE) platform for SDR receiver is ...In radio receivers,complete implementation of the software defined radio(SDR) concept is mainly limited by frontend.Based on bandpass sampling(BPS) theory,a flexible digital frontend(DFE) platform for SDR receiver is designed.In order to increase the processing speed,Gigabit Ethernet was applied in the platform at speed of 5×10~8 bit/s.By appropriate design of interpolant according to the position of input RF signals,multi-band receiving can be realized in the platform with suppression more than 35 d B without changing hardware.展开更多
Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processin...Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processing. Such system can help accelerate research and development of future wireless network, especially in the case of cellular/Wi-Fi co-existing networks. This platform is based on the Intel general-purpose processor and the universal software radio peripheral(USRP) radio front end. The design including the physical layer implementations is purely software and is optimized for real-time signal processing on the general purpose processor. In the lab experiment, this platform supports baseband rate up to 700 Mbps with 2 transmitters in 80 MHz bandwidth. A cellular-Wi-Fi signaling interface between the Wi-Fi access point(AP) and the 5G core network is also developed and validated as an example for wireless resource allocation.展开更多
为有效检测树干分层介质厚度和相对介电常数,该研究提出一种基于雷达探测的树干分层结构介电参数反演方法。基于斯涅耳定律结合树干生理结构特点,构建雷达信号在树干分层结构中的传播模型。利用软件定义无线电平台(software defined rad...为有效检测树干分层介质厚度和相对介电常数,该研究提出一种基于雷达探测的树干分层结构介电参数反演方法。基于斯涅耳定律结合树干生理结构特点,构建雷达信号在树干分层结构中的传播模型。利用软件定义无线电平台(software defined radio,SDR)搭建树干探测雷达。然后采用稀疏分解算法、K-SVD字典训练以及层剥离算法对探测雷达回波信号进行参数反演,并对不同的稀疏分解算法反演结果进行了对比。试验表明在回波混叠和无混叠的情况下,该方法均能够对树干分层介质厚度和相对介电常数进行估算;无混叠时相对介电常数和厚度的反演误差分别在2.93%和3.5%以内,混叠时相对介电常数和厚度的反演误差分别在7.52%和7.61%以内。综合试验结果表明,在5种反演算法中,SAMP算法在未知信号稀疏度的条件下表现最佳,具有较高的反演准确率和鲁棒性。展开更多
Vehicular Ad Hoc Networks (VANETs) are critical for the advancement of Intelligent Transportation Systems (ITS), enabling real-time vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications. However,...Vehicular Ad Hoc Networks (VANETs) are critical for the advancement of Intelligent Transportation Systems (ITS), enabling real-time vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications. However, ensuring Quality of Service (QoS) in VANETs is challenging due to high mobility, dynamic topologies, and interference. This study evaluates the performance of Medium Access Control (MAC) protocols implemented on a Software-Defined Radio (SDR) platform to address these challenges. The research highlights the use of QoS-prescribed scheduling algorithms and multi-user detection techniques to optimize key performance metrics such as packet delivery ratio (PDR), throughput, and scalability. Simulation results demonstrate significant improvements under varying mobility and channel conditions, achieving stable communication and high user capacity in both fixed and high-mobility scenarios. The findings underscore the potential of SDR-based VANET solutions for enhancing reliability, scalability, and efficiency in dynamic vehicular environments. Future directions include incorporating iterative methods and real-world testing to further refine QoS delivery in VANETs.展开更多
Vehicular Ad Hoc Networks (VANETs) play a pivotal role in the advancement of Intelligent Transportation Systems (ITS), facilitating real-time communication among vehicles (V2V) and between vehicles and infrastructure ...Vehicular Ad Hoc Networks (VANETs) play a pivotal role in the advancement of Intelligent Transportation Systems (ITS), facilitating real-time communication among vehicles (V2V) and between vehicles and infrastructure (V2I). However, maintaining reliable Quality of Service (QoS) in these dynamic environments remains challenging due to high mobility, frequent topology changes and interference. This paper proposes a robust cross-layer framework that integrates channel prediction and dynamic rate adaptation to address these challenges. The framework employs advanced multi-user detection techniques, including matched filters, successive interference cancellation (SIC), decorrelators and MMSE receivers, combined with adaptive multi-factor spreading, multi-code and multi-modulation transmission strategies. The study evaluates the framework’s performance through extensive simulations using a Software-Defined Radio (SDR) platform. Key findings demonstrate significant improvements in packet reception rate, throughput and spectral efficiency under various mobility and channel conditions. The proposed approach effectively mitigates interference and adapts to dynamic network environments, showcasing its potential to enhance reliability, scalability and efficiency in VANETs. Future work will explore real-world implementation and iterative algorithmic enhancements to further optimize QoS delivery in highly variable vehicular communication scenarios.展开更多
针对软件通信架构(Software Communication Architecture,SCA)核心框架在机载领域臃肿和低效等问题,提出了一种面向机载软件无线电(Software Defined Radio,SDR)系统的SCA核心框架优化方案。首先,为使架构轻量高效,提出功能单元裁剪方法...针对软件通信架构(Software Communication Architecture,SCA)核心框架在机载领域臃肿和低效等问题,提出了一种面向机载软件无线电(Software Defined Radio,SDR)系统的SCA核心框架优化方案。首先,为使架构轻量高效,提出功能单元裁剪方法;其次,针对时间优化问题,分析了SCA的局限性,提出可灵活配置的加载流程优化技术,在兼容SCA规范的基础上可根据实际系统特点实施灵活的组件加载,充分发挥系统的并行加载潜力来缩短加载时间。实验结果表明,所提的优化技术能够有效提升SDR系统可用性,对面向机载SDR系统的SCA架构优化设计和应用具有较强的指导意义。展开更多
雷达侦察系统对于配套实验用雷达信号发射机往往需要可以同时发射多种参数、软件可配置的雷达信号。针对实际需求,提出了一种基于软件无线电(software defined radio,SDR)可重构多通道雷达发射机系统,该系统以SDR平台为构架,通过现场可...雷达侦察系统对于配套实验用雷达信号发射机往往需要可以同时发射多种参数、软件可配置的雷达信号。针对实际需求,提出了一种基于软件无线电(software defined radio,SDR)可重构多通道雷达发射机系统,该系统以SDR平台为构架,通过现场可编程门阵列(field-programmable gate array,FPGA)实现多通道数字信道化发射机结构模型。在建立实信号信道化发射机基本数学模型的基础上,推导并得到了一种具有计算高效、结构简单的多通道雷达发射机模型。在基于SCA软件协议规范下,构建了SDR可重构多通道的雷达发射机模型,给出了硬件软件实现的基本框架和步骤。对提出的多通道雷达发射机高效结构模型进行了MATLAB仿真,验证了多通道雷达发射机高效结构模型的正确性。该结构模型已经在实际系统中得以应用,在工程应用方面具有一定的实用价值。展开更多
基金Project(2013QNA49)supported by the Fundamental Research Funds for the Central Universities,China
文摘In radio receivers,complete implementation of the software defined radio(SDR) concept is mainly limited by frontend.Based on bandpass sampling(BPS) theory,a flexible digital frontend(DFE) platform for SDR receiver is designed.In order to increase the processing speed,Gigabit Ethernet was applied in the platform at speed of 5×10~8 bit/s.By appropriate design of interpolant according to the position of input RF signals,multi-band receiving can be realized in the platform with suppression more than 35 d B without changing hardware.
基金supported in part by the National Natural Science Foundation of China under Grant No. 61671436the Science and Technology Commission Foundation of Shanghai under Grant No. 15511102602, 16511104204
文摘Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processing. Such system can help accelerate research and development of future wireless network, especially in the case of cellular/Wi-Fi co-existing networks. This platform is based on the Intel general-purpose processor and the universal software radio peripheral(USRP) radio front end. The design including the physical layer implementations is purely software and is optimized for real-time signal processing on the general purpose processor. In the lab experiment, this platform supports baseband rate up to 700 Mbps with 2 transmitters in 80 MHz bandwidth. A cellular-Wi-Fi signaling interface between the Wi-Fi access point(AP) and the 5G core network is also developed and validated as an example for wireless resource allocation.
文摘为有效检测树干分层介质厚度和相对介电常数,该研究提出一种基于雷达探测的树干分层结构介电参数反演方法。基于斯涅耳定律结合树干生理结构特点,构建雷达信号在树干分层结构中的传播模型。利用软件定义无线电平台(software defined radio,SDR)搭建树干探测雷达。然后采用稀疏分解算法、K-SVD字典训练以及层剥离算法对探测雷达回波信号进行参数反演,并对不同的稀疏分解算法反演结果进行了对比。试验表明在回波混叠和无混叠的情况下,该方法均能够对树干分层介质厚度和相对介电常数进行估算;无混叠时相对介电常数和厚度的反演误差分别在2.93%和3.5%以内,混叠时相对介电常数和厚度的反演误差分别在7.52%和7.61%以内。综合试验结果表明,在5种反演算法中,SAMP算法在未知信号稀疏度的条件下表现最佳,具有较高的反演准确率和鲁棒性。
文摘Vehicular Ad Hoc Networks (VANETs) are critical for the advancement of Intelligent Transportation Systems (ITS), enabling real-time vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications. However, ensuring Quality of Service (QoS) in VANETs is challenging due to high mobility, dynamic topologies, and interference. This study evaluates the performance of Medium Access Control (MAC) protocols implemented on a Software-Defined Radio (SDR) platform to address these challenges. The research highlights the use of QoS-prescribed scheduling algorithms and multi-user detection techniques to optimize key performance metrics such as packet delivery ratio (PDR), throughput, and scalability. Simulation results demonstrate significant improvements under varying mobility and channel conditions, achieving stable communication and high user capacity in both fixed and high-mobility scenarios. The findings underscore the potential of SDR-based VANET solutions for enhancing reliability, scalability, and efficiency in dynamic vehicular environments. Future directions include incorporating iterative methods and real-world testing to further refine QoS delivery in VANETs.
文摘Vehicular Ad Hoc Networks (VANETs) play a pivotal role in the advancement of Intelligent Transportation Systems (ITS), facilitating real-time communication among vehicles (V2V) and between vehicles and infrastructure (V2I). However, maintaining reliable Quality of Service (QoS) in these dynamic environments remains challenging due to high mobility, frequent topology changes and interference. This paper proposes a robust cross-layer framework that integrates channel prediction and dynamic rate adaptation to address these challenges. The framework employs advanced multi-user detection techniques, including matched filters, successive interference cancellation (SIC), decorrelators and MMSE receivers, combined with adaptive multi-factor spreading, multi-code and multi-modulation transmission strategies. The study evaluates the framework’s performance through extensive simulations using a Software-Defined Radio (SDR) platform. Key findings demonstrate significant improvements in packet reception rate, throughput and spectral efficiency under various mobility and channel conditions. The proposed approach effectively mitigates interference and adapts to dynamic network environments, showcasing its potential to enhance reliability, scalability and efficiency in VANETs. Future work will explore real-world implementation and iterative algorithmic enhancements to further optimize QoS delivery in highly variable vehicular communication scenarios.
文摘针对软件通信架构(Software Communication Architecture,SCA)核心框架在机载领域臃肿和低效等问题,提出了一种面向机载软件无线电(Software Defined Radio,SDR)系统的SCA核心框架优化方案。首先,为使架构轻量高效,提出功能单元裁剪方法;其次,针对时间优化问题,分析了SCA的局限性,提出可灵活配置的加载流程优化技术,在兼容SCA规范的基础上可根据实际系统特点实施灵活的组件加载,充分发挥系统的并行加载潜力来缩短加载时间。实验结果表明,所提的优化技术能够有效提升SDR系统可用性,对面向机载SDR系统的SCA架构优化设计和应用具有较强的指导意义。
文摘雷达侦察系统对于配套实验用雷达信号发射机往往需要可以同时发射多种参数、软件可配置的雷达信号。针对实际需求,提出了一种基于软件无线电(software defined radio,SDR)可重构多通道雷达发射机系统,该系统以SDR平台为构架,通过现场可编程门阵列(field-programmable gate array,FPGA)实现多通道数字信道化发射机结构模型。在建立实信号信道化发射机基本数学模型的基础上,推导并得到了一种具有计算高效、结构简单的多通道雷达发射机模型。在基于SCA软件协议规范下,构建了SDR可重构多通道的雷达发射机模型,给出了硬件软件实现的基本框架和步骤。对提出的多通道雷达发射机高效结构模型进行了MATLAB仿真,验证了多通道雷达发射机高效结构模型的正确性。该结构模型已经在实际系统中得以应用,在工程应用方面具有一定的实用价值。
