General purpose processer （GPP） based software-defined radio （SDR） platforms provide wireless communication system engineers with maximal architecture flexibility and versatility to construct a wideband wireless c...General purpose processer （GPP） based software-defined radio （SDR） platforms provide wireless communication system engineers with maximal architecture flexibility and versatility to construct a wideband wireless communication system. Nevertheless, the lack of hardware real-time timing control makes it difficult to achieve time synchronization between the base station and the terminals. In this paper, a software-based time synchronization （STS） method is proposed to realize the time synchronization of time division multiple access （TDMA） based wireless communication systems. A high precision software clock source is firstly constructed to measure the elapse of processing time. The Round-Trip Delay （RTD） algorithm is then presented to calculate timing advance values and achieve time synchronization. An example TDMA system is implemented on Microsoft Sora platforms to evaluate is effective to enable time synchronization for wideband the performance. Experiments show that the proposed mechanism wireless communication systems on GPP-based SDR platforms.展开更多
In multi-agent confrontation scenarios, a jammer is constrained by the single limited performance and inefficiency of practical application. To cope with these issues, this paper aims to investigate the multi-agent ja...In multi-agent confrontation scenarios, a jammer is constrained by the single limited performance and inefficiency of practical application. To cope with these issues, this paper aims to investigate the multi-agent jamming problem in a multi-user scenario, where the coordination between the jammers is considered. Firstly, a multi-agent Markov decision process (MDP) framework is used to model and analyze the multi-agent jamming problem. Secondly, a collaborative multi-agent jamming algorithm (CMJA) based on reinforcement learning is proposed. Finally, an actual intelligent jamming system is designed and built based on software-defined radio (SDR) platform for simulation and platform verification. The simulation and platform verification results show that the proposed CMJA algorithm outperforms the independent Q-learning method and provides a better jamming effect.展开更多
The Paper introduces an IF software radio receiver development Platform based on high-speed monolithic A/D Converter AD6640, Programmable Digital Down-converter AD6620 and high-speed DSP chip TMSC320C6701. The impleme...The Paper introduces an IF software radio receiver development Platform based on high-speed monolithic A/D Converter AD6640, Programmable Digital Down-converter AD6620 and high-speed DSP chip TMSC320C6701. The implementation method is described as well as AD6620 parameter setting analysis. It also presents a flow chart of the on-line programming with the help of PC. The algorithm for demodulation AM signal is discussed.展开更多
随着军用无人机等航电系统不断朝着小型化、智能化、综合化的方向发展,如何有效满足装备的低SWaP(Size,Weight and Power)要求成为一大难题。介绍了某型宽带综合化数字预处理模块的研制,利用“裸芯片+高密度基板”系统级封装(SiP)的方...随着军用无人机等航电系统不断朝着小型化、智能化、综合化的方向发展,如何有效满足装备的低SWaP(Size,Weight and Power)要求成为一大难题。介绍了某型宽带综合化数字预处理模块的研制,利用“裸芯片+高密度基板”系统级封装(SiP)的方式对信号处理平台(DSP、FPGA、SerDes和DDR芯片)进行集成,替代目前业界普遍采用的“封装芯片+印制板+平面集成”的传统方式,实现宽带综合化数字信号处理模块的高密度集成。在主要性能指标(可编程逻辑资源、定点处理能力、浮点处理能力、数据传输速率)不变的情况下,使得信号处理模块的面积降低为45 mm×45 mm,重量降低到103 g。展开更多
A Stewart platform is introduced in thc 500 m aperture spherical radio telescope（FAST） as an accuracy adjustable mechanism for teed receivers. Accuracy analysis is the basis of accuracy design. However, a rapid and ...A Stewart platform is introduced in thc 500 m aperture spherical radio telescope（FAST） as an accuracy adjustable mechanism for teed receivers. Accuracy analysis is the basis of accuracy design. However, a rapid and effective accuracy analysis method for parallel manipulator is still needed. In order to enhance solution efficiency, an interval analysis method（lA method） is introduced to solve the terminal error bound of the Stewart platform with detailed solution path. Taking a terminal pose of the Stewart platform in FAST as an example, the terminal error is solved by the Monte Carlo method（MC method） by 4 980 s, the stochastic mathematical method（SM method） by 0.078 s, and the IA method by 2.203 s. Compared with MC method, the terminal error by SM method leads a 20% underestimate while the IA method can envelop the real error bound of the Stewart platform. This indicates that the IA method outperforms the other two methods by providing quick calculations and enveloping the real error bound of the Stewart platform. According to the given structural error of the dimension parameters of the Stewart platform, the IA method gives a maximum position error of 19.91 mm and maximum orientation error of 0.534°, which suggests that the IA method can be used for accuracy design of the Stewart platfbnn in FAST. The 1A method presented is a rapid and effective accuracy analysis method for Stewart platform.展开更多
基金Supported by the Major Project of Beijing Municipal Natural Science Foundation of China under Grant No. 4110001
文摘General purpose processer （GPP） based software-defined radio （SDR） platforms provide wireless communication system engineers with maximal architecture flexibility and versatility to construct a wideband wireless communication system. Nevertheless, the lack of hardware real-time timing control makes it difficult to achieve time synchronization between the base station and the terminals. In this paper, a software-based time synchronization （STS） method is proposed to realize the time synchronization of time division multiple access （TDMA） based wireless communication systems. A high precision software clock source is firstly constructed to measure the elapse of processing time. The Round-Trip Delay （RTD） algorithm is then presented to calculate timing advance values and achieve time synchronization. An example TDMA system is implemented on Microsoft Sora platforms to evaluate is effective to enable time synchronization for wideband the performance. Experiments show that the proposed mechanism wireless communication systems on GPP-based SDR platforms.
基金supported by National Natural Science Foundation of China (No. 62071488 and No. 62061013)
文摘In multi-agent confrontation scenarios, a jammer is constrained by the single limited performance and inefficiency of practical application. To cope with these issues, this paper aims to investigate the multi-agent jamming problem in a multi-user scenario, where the coordination between the jammers is considered. Firstly, a multi-agent Markov decision process (MDP) framework is used to model and analyze the multi-agent jamming problem. Secondly, a collaborative multi-agent jamming algorithm (CMJA) based on reinforcement learning is proposed. Finally, an actual intelligent jamming system is designed and built based on software-defined radio (SDR) platform for simulation and platform verification. The simulation and platform verification results show that the proposed CMJA algorithm outperforms the independent Q-learning method and provides a better jamming effect.
文摘The Paper introduces an IF software radio receiver development Platform based on high-speed monolithic A/D Converter AD6640, Programmable Digital Down-converter AD6620 and high-speed DSP chip TMSC320C6701. The implementation method is described as well as AD6620 parameter setting analysis. It also presents a flow chart of the on-line programming with the help of PC. The algorithm for demodulation AM signal is discussed.
基金supported by National Natural Science Foundation of China (Grant Nos. 10973023,11103046,11203048)
文摘A Stewart platform is introduced in thc 500 m aperture spherical radio telescope（FAST） as an accuracy adjustable mechanism for teed receivers. Accuracy analysis is the basis of accuracy design. However, a rapid and effective accuracy analysis method for parallel manipulator is still needed. In order to enhance solution efficiency, an interval analysis method（lA method） is introduced to solve the terminal error bound of the Stewart platform with detailed solution path. Taking a terminal pose of the Stewart platform in FAST as an example, the terminal error is solved by the Monte Carlo method（MC method） by 4 980 s, the stochastic mathematical method（SM method） by 0.078 s, and the IA method by 2.203 s. Compared with MC method, the terminal error by SM method leads a 20% underestimate while the IA method can envelop the real error bound of the Stewart platform. This indicates that the IA method outperforms the other two methods by providing quick calculations and enveloping the real error bound of the Stewart platform. According to the given structural error of the dimension parameters of the Stewart platform, the IA method gives a maximum position error of 19.91 mm and maximum orientation error of 0.534°, which suggests that the IA method can be used for accuracy design of the Stewart platfbnn in FAST. The 1A method presented is a rapid and effective accuracy analysis method for Stewart platform.
