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1.
针对LTE-A新增的UE专用参考信号与小区参考信号映射的时频资源不同,导致传统的解调算法在UE专用参考信号上无法适用的问题。充分研究了UE专用参考信号时频资源映射的特点,即端口间采用了频分复用和码分复用技术区分,而小区参考信号只采用了频分复用技术,结合此特点与传统的解调算法原理,设计了2种利用专用导频信息的解调算法,即LS-UE算法和LMMSE-UE算法。最后,通过在EPA无线信道环境下,对2种解调算法的性能仿真,权衡实现的复杂度,选择一种更适合LTE-A系统的下行解调算法,即LS-UE算法,并对该算法的多核DSP实现,验证了该算法的可行性与高效性。  相似文献   

2.
采用FPGA设计实现一种通信信号处理单元,能达到多高的频率和多宽的带宽,主要取决于它数据的吞吐率,而内部数据的存取管理方式常常是提高数据吞吐率的关键。文中提出一种存取管理算法,并通过一种专用FPGA设计验证了这种算法的合理性,说明该算法具有推广应用的价值。  相似文献   

3.
实验型多功能可编程高速雷达数字信号处理系统采用先进高速通用信号处理芯片做主处理器;高速专用信号处理芯片做加速处理器构成多指令多数据流(MIMD)并行阵列处理系统,能适应于复杂干扰环境下多功能雷达高速自适应信号处理器的设计要求。系统具有多功能高速信号处理能力和模块化灵活构型的拓扑结构,便于映射广泛的先进雷达信号处理算法,系统具有批处理和流水处理两种方式,信号速率达10M/s。本文对系统总体方案及其硬件实现做了详细论述。  相似文献   

4.
为提高光电轴角编码器的细分精度及莫尔条纹光电信号的细分倍数,设计了一种基于改进粒子群算法的信号正弦性修正方法。首先,根据莫尔条纹光电信号的数学模型,分析信号质量指标对细分误差的影响;并从编码器的制作、调试、使用等环节出发,指出信号细分误差产生的根本原因;然后,对改进粒子群算法的基本原理和实现步骤做了具体阐述;最后,以21 位光电编码器为实验对象,依据其精码转换的方波信息实现精码信号的自适应采样,同时应用改进算法对采集的编码器原始光电信号进行数据预处理,通过辨识信号模型中的3 个待定参量,直接实现信号等幅性偏差、稳定性偏差、正交性偏差的修正;对算法处理后的莫尔条纹信号进行细分精度检测,实验结果表明:编码器细分误差峰值由19.08降低到2.86,细分精度明显提高。  相似文献   

5.
快速傅里叶变换(FFT)是一种将信号从时域变换到频域的变换形式,是声学、图像、电信和信号处理等领域中一种重要的分析工具。近年来,专用的数字信号处理器以其优化的硬件结构和优良的性能价格比为FFT的实现提供了一个有效的途径。详细介绍了以浮点型DSP5416为核心的实现FFT算法的硬件平台设计。  相似文献   

6.
通常DDS信号发生器设计主要分为两类,一类是采用FPGA设计,另一类采用单片机+DDS专用芯片实现。本文针对频率及要求较低的应用,提出一种更为简单的解决方案,即通过单片机编程完成DDS算法,从而实现信号发生器功能。  相似文献   

7.
郑翔  张文强  周志杰 《电讯技术》2006,46(2):164-167
针对通信线路频响差导致信号变化范围大、大信号屏蔽小信号的问题,设计和实现了一种自动增益控制(AGC)算法。采用过采样和数字滤波技术,增加了模拟信号的转换位数,增大了AGC的动态范围;采用可变步长设计加快了AGC的收敛速度。  相似文献   

8.
为解决频域法实现信号匹配滤波时硬件开销较大的问题,采用时域法实现线性调频(LFM)信号的匹配滤波。设计了一款针对LFM信号的8阶分布式结构的时域匹配滤波器;利用FPGA的ROM宏模块构建查找表,实现分布式滤波算法;基于FPGA器件完成了滤波器的设计与集成。仿真结果显示,滤波器占用170个逻辑单元、109个寄存器、3K字节存储器,逻辑资源开销较小。与传统FIR结构的乘累加算法相比,分布式滤波算法运算速度更快。  相似文献   

9.
孙重磊 《电子科技》2012,25(9):132-135
基于Good—Thomas映射算法和ISE快速傅里叶变换IP核,设计了一种易于FPGA实现的24点离散傅里叶变换,所设计的24点DFF模块采用流水线结构,主要由3个8点FFT模块和1个3点DFT模块级联而成。并且两级运算之间不需要旋转因子,整个DFF模块仅仅需要14个实数乘法器,布局布线后仿真工作时钟频率可达200MHz。首先根据Good—Thomas算法将并行的24路输入信号分成3组,每组8路信号,并进行并/串转换,得到3路串行信号;其次。将3路串行信号分别输入至3个FFrIP核模块进行8点FFT运算;然后,将上述3个FFrIP核模块同一时刻输出的3路信号进行3点DFF变换;最后,将得到的3路并行输出信号分别进行串/并转换,得到24路DFF输出信号。此外,设计的24点DFT结构还具有很好的扩展性,通过修改FFTIP核变换点数参数便可实现长度N=3×2^N点DFT。  相似文献   

10.
对主动噪声控制系统的前馈型、反馈型和混合型3种控制方式进行了比较,利用Simulink设计了实现FxLMS算法的模块,并进行仿真。结果表明,前馈型控制方式可降低与参考信号相关的噪声;反馈型控制方式可降低可预测的噪声;而混合型控制方式可同时降低这2种噪声。  相似文献   

11.
魏小源  杨媛  王洋 《压电与声光》2017,39(6):939-944
鉴于超声换能器(换能器)传统驱动电路中存在发射效率低,激励信号有拖尾的问题,该文提出了一种改进型驱动电路方案。首先,对换能器匹配和激励信号拖尾吸收的理论进行说明,并从匹配和拖尾吸收等方面综合考虑对驱动电路进行改进;其次,采用一发一收的机制,在600m60型钢轨上搭建实验平台,并对传统无匹配、有匹配驱动电路和该文设计的驱动电路的性能进行对比。实验结果表明,与传统无匹配驱动电路相比,改进型驱动电路消除了激励信号拖尾且波形光滑,接收信号中心频点相对幅值提高了98.97%;与传统有匹配驱动电路相比,改进型驱动电路消除了激励信号拖尾且波形光滑,接收信号中心频点相对幅值提高了50.45%。  相似文献   

12.
A typical digital image communication system based on a number of ASIC architectural designs is currently under development. After partitioning the complete system into several stages, each selected algorithm can be implemented on a single ASIC based on an efficient architectural style. The required throughput for high-performance data compression and channel coding has been obtained due to the optimization of the critical path in the architectural design. Input/output (I/O) operations, which create the bottleneck for many image-processing algorithms, are handled by a dedicated I/O interface unit. Construction of each dedicated data path in the architecture is based on a limited parameterizable functional building block (FBB) library. The dedicated data paths have been constructed by partitioning the initial signal flow graph (SFG) into compatible graphs and by matching the graphs in each partition onto a collection of time-multiplexed FBBs. Hierarchically partitioned controllers were used to meet the high-throughput requirements. The ASIC architectures proposed are oriented to broadband integrated services digital networks (B-ISDN) as well as high-performance digital image compression systems  相似文献   

13.
Gradient Pursuits   总被引:6,自引:0,他引:6  
Sparse signal approximations have become a fundamental tool in signal processing with wide-ranging applications from source separation to signal acquisition. The ever-growing number of possible applications and, in particular, the ever-increasing problem sizes now addressed lead to new challenges in terms of computational strategies and the development of fast and efficient algorithms has become paramount. Recently, very fast algorithms have been developed to solve convex optimization problems that are often used to approximate the sparse approximation problem; however, it has also been shown, that in certain circumstances, greedy strategies, such as orthogonal matching pursuit, can have better performance than the convex methods. In this paper, improvements to greedy strategies are proposed and algorithms are developed that approximate orthogonal matching pursuit with computational requirements more akin to matching pursuit. Three different directional optimization schemes based on the gradient, the conjugate gradient, and an approximation to the conjugate gradient are discussed, respectively. It is shown that the conjugate gradient update leads to a novel implementation of orthogonal matching pursuit, while the gradient-based approach as well as the approximate conjugate gradient methods both lead to fast approximations to orthogonal matching pursuit, with the approximate conjugate gradient method being superior to the gradient method.  相似文献   

14.
Techniques for implementation of digital signal processing (DSP) algorithms on synchronous multiprocessors studied for the past ten years are discussed. This research is characterised as a theoretical investigation of optimality criteria for the implementation of DSP algorithms and the development of a unique approach that can achieve these optimality criteria. A result of this ongoing research program has been the development of a set of formal techniques for the automatic realization of optimal synchronous supercomputer implementations for a large class of iterative or recursive DSP algorithms. Three experimental laboratory digital signal microprocessor (DSMP) systems designed to provide experimental verification of the theoretical results are described. This has provided important feedback to drive the theoretical developments. Compilers that take flow graph specifications of algorithms and generate optimal multiprocessor code are also discussed  相似文献   

15.
为了增强康复理疗仪的性能、治疗效果及人机交互性,设计并研制了多功能康复理疗仪。根据康复理疗仪输出信号特点,在Exynos4412主处理器基础上,设计康复理疗仪信号发生与调理电路;根据康复理疗仪输出波形特点,在驱动电路和软件技术基础上,设计并实现了组合脉冲波形,达到了锤击、按摩和刮痧等效果;与此同时,在功能设计上增加了记忆模式、理疗参数调节模式等。经测试,理疗仪性能优、效果好、人机交互性强,具有较好的应用前景。  相似文献   

16.
热成像设备测试方法的实验及分析   总被引:2,自引:0,他引:2  
雷萍  吴文华  朱祺 《激光与红外》2013,43(9):1017-1020
设计了一种以信号标准化、温度控制精确化、结构微型化为要求的热成像设备关键指标测试方法。在实验室对噪声等效温差、最小可分辨温差、调制传递函数、信号传递函数等指标进行测试,对测试中的问题进行了分析,提出了在多种温度不同增益下测试噪声等效温差、利用神经网络算法在内多种算法提高分辨图像能力的方法,实验结果表明,方法有效可行,提高了对热成像设备检测的能力。  相似文献   

17.
针对功率型光电检测电路微弱光信号检测和功率输出的需求,研制了一种集成光电探测传感器和信号处理电路,且带功率驱动功能的单片光电检测电路.从理论上探讨了光电探测器的工艺兼容与系统噪声匹配,设计了专用的光电探测器以及适用于功率型光电集成电路(OEIC)的信号处理单元.采用B6035双极工艺,进行了版图设计和流片测试.测试结果表明,该电路的电源电压工作范围、静态功耗和传输延迟时间等综合性能优于同类型混合组装电路.  相似文献   

18.
A configurable architecture for performing image transform algorithms is presented that provides a better tradeoff between low complexity and algorithm flexibility than either software-programmable processors or dedicated ASIC's. The configurable processor unit requires only 110 K transistors and can execute several image transform algorithms. By emulating the signal flow of the algorithms in hardware, rather than software, complexity is reduced by an order of magnitude compared with current software programmable video signal processors, while providing more flexibility than single function ASIC's. The processor has been fabricated in 1.2-μm CMOS and has been successfully used to execute the discrete cosine transform/inverse discrete cosine transform (DCT/IDCT), subband coding, vector quantization, and two-dimensional filtering algorithms at pixel rates up to 25 MPixels/s  相似文献   

19.
In this paper, a model-based tracking control is proposed for a mechanism dedicated to accurately reproduce the breathing-induced motion of a human lung tumour. In former work, a 3-dimensional mechanism equipped with three pneumatically driven axes has been developed and constructed for this purpose. The overall control structure consists of decentralised axis controller for each pneumatic cylinder with a cascaded structure: A fast inner control loop governs the pressure induced drive force using backstepping techniques, whereas the outer control loop is related to an optimal, robust position control of the cylinder. Additionally, discrete-time iterative learning controllers are utilised to compensate lumped disturbance forces and model uncertainties. The suggested overall control structure has been implemented on the innovative test rig and successfully validated in a clinical framework. The given work represents the basis for future improvements of algorithms regarding PET/CT-imaging as well as radiotherapy.  相似文献   

20.
宋凯  朱文涛 《现代导航》2018,9(3):216-219
在雷达多脉冲相参积累过程中,高速机动目标的速度模型可建模为三次相位信号, 其中,调频率和二次调频率是引起多普勒频移的因素。如何快速估计调频率和二次调频率对雷达多脉冲相参积累至关重要。针对传统算法在三次相位信号参数估计中存在低计算复杂度与高抗噪声性能矛盾的问题,本文提出一种基于非均匀傅立叶变换的三次相位信号参数估计方法。首先, 基于非均匀傅立叶变换对 HAF-ICPF 方法进行改进;然后,利用改进的 HAF-ICPF 方法估计三次相位信号的参数。改进的 HAF-ICPF 方法由于避免了复杂的搜索过程,在保持原有高抗噪声性能的基础上,大大降低了计算复杂度。仿真结果验证了方法的有效性。  相似文献   

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