A discrete model is set up for High Resolution Range Profile (HRRP) of an extended target and the model of echo from an extended target for a Stepped Chirp Radar (SCR) is proposed. The effect of target motion on a ran...A discrete model is set up for High Resolution Range Profile (HRRP) of an extended target and the model of echo from an extended target for a Stepped Chirp Radar (SCR) is proposed. The effect of target motion on a range profile is thoroughly analyzed, and based on which precision re- quirement is developed for motion compensation. By studying the time domain correlation and the rule based on the least burst error, a motion compensation algorithm which satisfies the project requirement is presented, and the cyber-emulation confirms the conclusion. At last the processor is designed by using DSP devices to realize motion compensation and target recognition.展开更多
The Orthogonal Frequency Division Multiplexing (OFDM) system is already used in commercial applications and is capable to deal with Intersymbolic Interference (ISI) caused by multipath channels. This system gained pop...The Orthogonal Frequency Division Multiplexing (OFDM) system is already used in commercial applications and is capable to deal with Intersymbolic Interference (ISI) caused by multipath channels. This system gained popularity after the application of the Fast Fourier Transform (FFT) and its inverse (IFFT) to modulate the signal in many subcarriers. This paper discusses implementation aspects of an OFDM system;such system is characterized by considering real constraints, including the memory consumption and the processing time. The OFDM modulator, channel samples and OFDM demodulator were implemented entirely in the DSP TMS320C6678 platform. As a proof-of-concept, a 256-QAM OFDM BER performance is compared with theoretical values. Moreover, the memory size is not demanding, consuming very few resources. It was observed a very high number of DSP clock cycles needed for the OFDM signal modulation, corresponding to more than 4 times the number used in demodulating the signal.展开更多
The complexity/performance balanced decoder for low-density parity-check （LDPC） codes is preferred in practical wireless communication systems. A low complexity LDPC decoder for the Consultative Committee for Space ...The complexity/performance balanced decoder for low-density parity-check （LDPC） codes is preferred in practical wireless communication systems. A low complexity LDPC decoder for the Consultative Committee for Space Data Systems （CCSDS） standard is achieved in DSP. An ap- proximate decoding algorithm, normalized rain-sum algorithm, is used in the implementation for its low amounts of computation. To reduce the performance loss caused by the approximation, the pa- rameters of the normalized min-sum algorithm are determined by calculating and finding the mini- mum value of thresholds through density evolution. The minimum value which indicates the best per- formance of the decoding algorithm is corresponding with the optimized parameters. In implementa- tion, the memory cost is saved by decomposing the parity-check matrix into submatrices to store and the computation of passing message in decoding is accelerated by using the intrinsic function of DSP. The performance of the decoder with optimized factors is simulated and compared with the ideal BP decoder. The result shows they have about the same performance.展开更多
The human brain is a complex intelligent system composed of tens of billions of neurons interconnected through synapses,and its intricate network structure has consistently attracted numerous scientists to explore the...The human brain is a complex intelligent system composed of tens of billions of neurons interconnected through synapses,and its intricate network structure has consistently attracted numerous scientists to explore the mysteries of brain functions.However,most existing studies have only verified the biological mimicry characteristics of memristors at the single neuron-synapse level,and there is still a lack of research on memristors simulating synaptic coupling between neurons in multi-neuron networks.Based on this,this paper uses discrete memristors to couple dual discrete Rulkov neurons,and adds synaptic crosstalk between the two discrete memristors to form a neuronal network.A memristor-coupled dual-neuron map,called the Rulkov-memristor-Rulkov(R-M-R)map,is constructed to simulate synaptic connections between neurons in biological tissues.Then,the equilibrium points of the R-M-R map are studied.Subsequently,the effect of parameter variations on the dynamic performance of the R-M-R map is comprehensively analyzed using bifurcation diagram,phase diagram,Lyapunov exponent spectrum(LEs),firing diagram,and spectral entropy(SE)complexity algorithms.In the RM-R map,diverse categories of periodic,chaotic,and hyperchaotic attractors,as well as different states of firing patterns,can be observed.Additionally,different types of state transitions and coexisting attractors are discovered.Finally,the feasibility of the model in digital circuits is verified using a DSP hardware platform.In this study,the coupling principle of biological neurons is simulated,the chaotic dynamic behavior of the R-M-R map is analyzed,and a foundation is laid for deciphering the complex working mechanisms of the brain.展开更多
研究了一种基于IEEE802.16e的正交频分复用(orthogonal frequency division multiplexing,OFDM)定时同步算法,结合IEEE802.16e协议定义的OFDM帧结构特点,给出了面向DSP硬件平台的OFDM系统中同步子系统实现方案,最后利用TI公司的TMS320C6...研究了一种基于IEEE802.16e的正交频分复用(orthogonal frequency division multiplexing,OFDM)定时同步算法,结合IEEE802.16e协议定义的OFDM帧结构特点,给出了面向DSP硬件平台的OFDM系统中同步子系统实现方案,最后利用TI公司的TMS320C6416对该方案进行了实现。结果表明,提出的实现方案具有良好的性能。展开更多
提出了一种基于TMS320VC549定点DSP微处理器芯片的语音信号压缩/解压缩处理系统。该系统采用TLC320AD50C模数、数模转换器,采样率为8 kHz,处理能力为100 M IPS。系统配置有大容量存储器,具备资源扩展能力,适用于语音信号压缩/解压缩和...提出了一种基于TMS320VC549定点DSP微处理器芯片的语音信号压缩/解压缩处理系统。该系统采用TLC320AD50C模数、数模转换器,采样率为8 kHz,处理能力为100 M IPS。系统配置有大容量存储器,具备资源扩展能力,适用于语音信号压缩/解压缩和语音识别、语音合成等其他领域。实验结果表明,系统对语音信号的压缩解压缩处理具有稳定性、灵活性和通用性。展开更多
基金Supported by National Natural Science Foundation of China (No.60402032).
文摘A discrete model is set up for High Resolution Range Profile (HRRP) of an extended target and the model of echo from an extended target for a Stepped Chirp Radar (SCR) is proposed. The effect of target motion on a range profile is thoroughly analyzed, and based on which precision re- quirement is developed for motion compensation. By studying the time domain correlation and the rule based on the least burst error, a motion compensation algorithm which satisfies the project requirement is presented, and the cyber-emulation confirms the conclusion. At last the processor is designed by using DSP devices to realize motion compensation and target recognition.
文摘The Orthogonal Frequency Division Multiplexing (OFDM) system is already used in commercial applications and is capable to deal with Intersymbolic Interference (ISI) caused by multipath channels. This system gained popularity after the application of the Fast Fourier Transform (FFT) and its inverse (IFFT) to modulate the signal in many subcarriers. This paper discusses implementation aspects of an OFDM system;such system is characterized by considering real constraints, including the memory consumption and the processing time. The OFDM modulator, channel samples and OFDM demodulator were implemented entirely in the DSP TMS320C6678 platform. As a proof-of-concept, a 256-QAM OFDM BER performance is compared with theoretical values. Moreover, the memory size is not demanding, consuming very few resources. It was observed a very high number of DSP clock cycles needed for the OFDM signal modulation, corresponding to more than 4 times the number used in demodulating the signal.
基金Supported by the National Natural Science Foundation of China (61205116)
文摘The complexity/performance balanced decoder for low-density parity-check （LDPC） codes is preferred in practical wireless communication systems. A low complexity LDPC decoder for the Consultative Committee for Space Data Systems （CCSDS） standard is achieved in DSP. An ap- proximate decoding algorithm, normalized rain-sum algorithm, is used in the implementation for its low amounts of computation. To reduce the performance loss caused by the approximation, the pa- rameters of the normalized min-sum algorithm are determined by calculating and finding the mini- mum value of thresholds through density evolution. The minimum value which indicates the best per- formance of the decoding algorithm is corresponding with the optimized parameters. In implementa- tion, the memory cost is saved by decomposing the parity-check matrix into submatrices to store and the computation of passing message in decoding is accelerated by using the intrinsic function of DSP. The performance of the decoder with optimized factors is simulated and compared with the ideal BP decoder. The result shows they have about the same performance.
基金supported by the National Natural Science Foundation of China(Grant No.62571079)the Technological Innovation Projects in the Field of Artificial Intelligence in Liaoning Province(Grant No.2023JH26/10300011)+1 种基金the Basic Scientific Research Projects in the Department of Education of Liaoning Province(Grant No.LJ212410152049)the Liaoning Provincial Science and Technology Plan Joint Project(Grant No.2025-BSLH-041)。
文摘The human brain is a complex intelligent system composed of tens of billions of neurons interconnected through synapses,and its intricate network structure has consistently attracted numerous scientists to explore the mysteries of brain functions.However,most existing studies have only verified the biological mimicry characteristics of memristors at the single neuron-synapse level,and there is still a lack of research on memristors simulating synaptic coupling between neurons in multi-neuron networks.Based on this,this paper uses discrete memristors to couple dual discrete Rulkov neurons,and adds synaptic crosstalk between the two discrete memristors to form a neuronal network.A memristor-coupled dual-neuron map,called the Rulkov-memristor-Rulkov(R-M-R)map,is constructed to simulate synaptic connections between neurons in biological tissues.Then,the equilibrium points of the R-M-R map are studied.Subsequently,the effect of parameter variations on the dynamic performance of the R-M-R map is comprehensively analyzed using bifurcation diagram,phase diagram,Lyapunov exponent spectrum(LEs),firing diagram,and spectral entropy(SE)complexity algorithms.In the RM-R map,diverse categories of periodic,chaotic,and hyperchaotic attractors,as well as different states of firing patterns,can be observed.Additionally,different types of state transitions and coexisting attractors are discovered.Finally,the feasibility of the model in digital circuits is verified using a DSP hardware platform.In this study,the coupling principle of biological neurons is simulated,the chaotic dynamic behavior of the R-M-R map is analyzed,and a foundation is laid for deciphering the complex working mechanisms of the brain.
文摘研究了一种基于IEEE802.16e的正交频分复用(orthogonal frequency division multiplexing,OFDM)定时同步算法,结合IEEE802.16e协议定义的OFDM帧结构特点,给出了面向DSP硬件平台的OFDM系统中同步子系统实现方案,最后利用TI公司的TMS320C6416对该方案进行了实现。结果表明,提出的实现方案具有良好的性能。
文摘提出了一种基于TMS320VC549定点DSP微处理器芯片的语音信号压缩/解压缩处理系统。该系统采用TLC320AD50C模数、数模转换器,采样率为8 kHz,处理能力为100 M IPS。系统配置有大容量存储器,具备资源扩展能力,适用于语音信号压缩/解压缩和语音识别、语音合成等其他领域。实验结果表明,系统对语音信号的压缩解压缩处理具有稳定性、灵活性和通用性。
