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991.
992.
Clutter suppression method in GPR using particle clustering 总被引:1,自引:0,他引:1
In this paper, a novel clutter suppression method in Ground Penetrating Radar (GPR) is proposed. Time segments of hill are represented by their corresponding particle in B-scan. Those particles in B-scan are clustered to represent reflectors (such as buried targets, air-soil interface). The clusters of buried target have a particle sequence with single peak. Therefore, if the particles donot belong to the cluster of buried target, time segment they represent will be suppressed. Experimental results and simulation are provided to demonstrate that the new algorithm outperforms existing ap-proaches. 相似文献
993.
This paper presents a new Transmitted Reference (TR) Ultra-WideBand (UWB) receiver based on Spatial Diversity (SD), which employs Multi-Antenna Technology (MAT) to improve the performance of TR-UWB receiver. According to the amplitude of correlator output of every antenna branch, this paper analyzed the performances of the proposed TR-UWB receiver employing three different kinds of combina-tion strategies, i.e., Maximum Ratio Combination (MRC), Equal Gain Combination (EGC), and Selective Combination (SC), which are different from conventional ones, and theoretically proved that the performance of EGC is better than MRC. Simulation results verify that when EGC is adopted and BER=10–3, increasing three antennas provides Signal to Noise Ratio (SNR) gain of about 3 dB in CM4 channel and SNR gain of about 2 dB in CM2 channel. 相似文献
994.
介绍了一个基于DMB-TH的自适应调制器的解决方案。经前端信源编码后的TS码流通过高速的串行通信接收器进入调制器模块,调制器模块由FPGA实现对TS码流的随机化、信道编码和调制,其中详细介绍了信道级联编码的实现方法。为了实现白适应,DVB—T射频信号通过天线耦合到变频器电路的前端双工滤波器,再经过处理,变为DMB—TH信号发射出去。 相似文献
995.
Ashok Kavithamani Venugopal Manikandan Nanjundappan Devarajan 《Journal of Electronic Testing》2011,27(5):673-678
A method for detection of parametric faults occurring in linear analog circuits based on location of poles of the Circuit
Under Test (CUT) is proposed. In the proposed method, the value of each component of the CUT is varied within its tolerance
limit using monte carlo simulation. The upper and lower bounds of magnitude, phase angle, real part and imaginary part of
all poles of the CUT are obtained. While testing, the locations of poles are obtained. If any one or more of the poles lies
outside the tolerance limit then the CUT is declared faulty. The effectiveness of the proposed method is validated through
two benchmark circuits like second order sallenkey band pass filter and fourth order leapfrog low pass filter. 相似文献
996.
Benedikt Scherger Steffen Wietzke Maik Scheller Nico Vieweg Matthias Wichmann Martin Koch Karin Wiesauer 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(7):943-951
We investigate different micro-powders that can be used as base materials for THz lenses fabricated by compression molding.
For this application materials with a very weak THz absorbance and low dispersion are required. By measuring the THz absorption
coefficient and refractive index of pellets pressed from the different micro-powders, we identify several materials that are
well suited for the fabrication of compression molded THz lenses (CMLs). In addition, a considerable range of the refractive
index is covered by the samples, which will allow for the fabrication of CMLs with different focal lengths for one and the
same lens design. 相似文献
997.
电脑等数字化物件及其网络将人类社会带入了数字化时代,其深远的影响力源于将现实世界蕴涵的信息进行了数字化(以数字0和1的组合来表示信息),并经过快速广泛的传播,形成虚拟世界。正是由于数字化以及信息的快速广泛传播导出了数字化时代的种种特征。数字化的虚拟世界是比由语言、符号所形成的模拟化的抽象世界更高级的社会形态,促使现实世界发生更深刻的变革。在数字化时代,人们有更强的求知欲和求真欲,对科普有更高的要求。数字科普由于其突出的优势,必将成为科普的主流。传统科普也将与数字科普相配合而呈现崭新的面貌,在许多场合发挥不可替代的作用。 相似文献
998.
提出将Altera公司的Nios Ⅱ软核嵌入到FPGA芯片内部来控制高性能直接数字频率合成器芯片AD9858的方法,在简要介绍Nios Ⅱ和AD9858的特性的基础上,详细说明了本系统的电路结构和软件设计方法,提出一种新的雷达信号源的设计方法,该系统具有集成度高、稳定性好和扩展性强等优点. 相似文献
999.
P.V. Ananda Mohan 《Circuits, Systems, and Signal Processing》2007,26(2):215-227
A new moduli set
derived from a recently proposed four moduli set
is considered, in this paper. The problem of reverse conversion has been considered, and it is shown that the proposed moduli
set needs less reverse conversion time and area requirements than the converter for the four moduli set
from which it is derived. The proposed moduli set is also compared with two other well-known three moduli sets
and
for realizing the same dynamic range regarding the area and conversion times of the residue number system (RNS)-to-binary
converters. 相似文献
1000.
Jean-François Saheb Jean-François Richard Mohamad Sawan Remi Meingan Yvon Savaria 《Analog Integrated Circuits and Signal Processing》2007,53(1):27-34
A system integration for High Voltage (HV) electrostatic MicroElectroMechanical Systems (MEMS) actuators is introduced on
a micro-Printed Circuit Board. The system includes a programmable microcontroller, a programmable DC/DC converter, a multi
output HV interface and electrostatic MEMS actuators. The system produces high output voltages (10–300 V) and can control
a large variety of MEMS capacitive loads (1 to 50 pF) by combining diverse semiconductor technologies. This system proves
that technologies, such as low voltage CMOS of different processes, high voltage DMOS and MEMS, can interact, communicate
and even be integrated as a System In Package (SIP), providing significant size and cost reductions. The system was programmed
to control electrostatic MEMS actuator. The DC/DC converter was made from components of different technologies and two addressable
high voltage CMOS interfaces were fabricated with DALSA's 0.8 μm High Voltage process. A prototype of the global system has
been built and tested. 相似文献