Description: 一个四用户的扩频通信系统，扩频增益为N=16，采用Walsh码进行直接序列扩频，BPSK调制，无线信道为AWGN(加性高斯白噪声信道)信道(AWGN信道：不考虑通信信道信号时，由宽频范围描述的统计随机无线噪声。)。在接收端进行解扩，解调，判决，通过仿真得到其中一个用户的误比特率与信噪比的仿真结果。-A four-user spread spectrum communication system, spreading gain for N = 16, using Walsh code Direct Sequence Spread Spectrum, BPSK modulation, channel for AWGN (additive white Gaussian noise channel) channel (AWGN channel: do not consider communication channel signals, described by the scope of broadband wireless random statistical noise.). At the receiving end for despreading, demodulation, judgments, through the simulation to be one of a user' s bit error rate and SNR of the simulation results. Platform: |
Size: 9216 |
Author:jehuty |
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Description: 一个四用户的扩频通信系统，扩频增益为N=16，采用Walsh码进行直接序列扩频，BPSK调制，无线信道为AWGN信道。在接收端进行解扩，解调，判决，通过仿真得到其中一个用户的误比特率与信噪比的仿真结果。-A four-user spread spectrum communication system, spreading gain for N = 16, using Walsh code Direct Sequence Spread Spectrum, BPSK modulation, AWGN channel for the wireless channel. At the receiving end for despreading, demodulation, judgments, through the simulation to be one of a user' s bit error rate and SNR of the simulation results. Platform: |
Size: 1024 |
Author:林立夫 |
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Description: 设计一个四用户的扩频通信系统，扩频增益为N=16，采用Walsh码进行直接序列扩频，BPSK调制，无线信道为AWGN信道。在接收端进行解扩，解调，判决，通过仿真得到其中一个用户的误比特率与信噪比的仿真结果。-Designed a four-user spread spectrum communication system, spreading gain for N = 16, using Walsh code Direct Sequence Spread Spectrum, BPSK modulation, AWGN channel for the wireless channel. At the receiving end for despreading, demodulation, judgments, through the simulation to be one of a user' s bit error rate and SNR of the simulation results. Platform: |
Size: 5120 |
Author:杨世斌 |
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Description: 利用M函数仿真扩频通信系统。6个用户的CDMA的同步通信系统，每个用户利用L＝31的Gold码，进行扩频，信道为AWGN信道，接收端利用匹配滤波器进行检测。绘出当N＝10000个发射比特下，SNR＝0：15（dB）时的误码率曲线。
-M function simulation using Spread Spectrum Communication System. 6 simultaneous users of CDMA communication system, each user of the L = 31 the use of Gold codes for spread spectrum, channel for the AWGN channel, the receiving end to detect the use of matched filter. Drawn when N = 10000 bits of transmission, SNR = 0:15 (dB) when the bit error rate curve. Platform: |
Size: 1024 |
Author:沈友俊 |
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Description: 灵巧干扰对直接序列扩频信号发射机和接收机的干扰仿真程序，包括通信发射机电路、接收机捕获电路、码跟踪电路、载波捕获电路、防假捕电路、信噪比估计电路和数据解调电路-Smart interference on direct sequence spread spectrum signal transmitter and receiver interference simulation program, including communications transmitter circuit, receiver capture circuit, code tracking circuit, the carrier capture circuit, anti-fake fishing circuit, SNR estimation circuit and data solution tone circuits, etc. Platform: |
Size: 47104 |
Author: yangle |
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Description: 这是一篇很好的有关信道估计的文章，
可以用来快速的了解信道估计的基本内容-In this paper, a method for fast blind estimation
of DS-SS signal is proposed which aims at the
Direct-Sequence Spread- Spectrum (DS-SS) signals
with parameters unknown. Considering the
characteristic that Pseudo-Random noise (PN)
sequence modulates the information symbol, we
make use of the method based on the second-order
cyclic-cumulant to estimate the period of PN
sequence, and then the method of segmented
cross-correlation to estimate the synchronous start
bit between the information symbols and the PN
codes. On base of this, a method of multiple
subsection cross-correlation average is used to
estimate the PN sequence. Computer simulations
show that the method can work well on signals at
low signal noise ratio (SNR). Platform: |
Size: 103424 |
Author:renkill |
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Description: IEEE经典文章，CDMA PN序列差分捕获技术，文章内容详细，对学习和从事直接序列扩频同步捕获CDMA系统设计人员有很大帮助，推荐-New differentially coherent detectors for acquisition of direct sequence spread-spectrum signals are ntroduced. These detectors are alternatives to the noncoherent detectors that have
been considered almost exclusively in the past. The proposed detectors are suitable for commercial code-division multiple-access(CDMA) systems which operate with a relatively large noise fl oor and provide a surprisingly large signal-to-noise ratio (SNR) improvement over the noncoherentdetectors of approximately 5 dB. Platform: |
Size: 293888 |
Author:caiyh |
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Description: 直接序列扩频的系统仿真，适合理解原理，很实用-Simulation of direct sequence spread spectrum system for understanding the principle, it is practical Platform: |
Size: 92160 |
Author:tobabby |
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Description: 为了进一步提高直接序列／跳频（ＤＳ／ＦＨ）扩频系统的抗干扰能力，基于小波包变换结合递归最小二乘算法设计
了一种变换域自适应干扰抑制算法，该算法采用小波包分解定位窄带干扰，递归最小二乘算法抑制窄带干扰。通过蒙特卡
罗仿真分析在增加抗干扰模块后，ＤＳ／ＦＨ系统工作在准静态时，在不同信噪比条件下抗窄带干扰性能。仿真结果表明：该
算法具有较强的自适应性以及抗窄带干扰能力，其性能优于传统的直接置零法，适用于多音干扰下的恶劣通信环境。-In order to further improve the anti-jamming capability of direct sequence/frequency-hopping spread spectrum system (DS/FH), based on wavelet packet transform combined with recursive least squares algorithm design a transform domain adaptive interference suppression algorithm, the algorithm uses wavelet packet decomposition positioning narrowband interference, narrowband interference suppression recursive least squares algorithm. By Monte Carlo simulation analysis to increase the anti-jamming module DS/FH system work in the quasi-static, in different SNR anti narrowband interference performance. Simulation results show that: the algorithm has strong adaptability and resistance to narrowband interference ability, its performance is superior to the traditional method of direct zero, poor communication environment suitable for multi-tone interference. Platform: |
Size: 301056 |
Author:dm |
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Description: 使用matlab及sinmulink对扩频系统进行仿真，并做出了误码率和信噪比的图形-To matlab and sinmulink spread spectrum system simulation, and make the BER and SNR graphics
Platform: |
Size: 14336 |
Author:chenming |
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Description: 编写了MATLAB程序生产和扩频码进行仿真，仿真程序从发送方完成通道的接收端，得出在不同的扩频码，在不同的信噪比即误码率的图形比较直接序列扩频通信系统原理，改善系统性能的度-Written MATLAB program to produce and direct sequence spread spectrum communication system principle of spreading codes for simulation, emulation program to complete the channel from the sender to the receiver end, draw graphics comparison at different spreading code, the bit error rate under different SNR i.e., the degree of improvement of the system performance Platform: |
Size: 6144 |
Author:吴晓 |
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Description: Direct sequence spread spectrum (DSSS) communication systems has been widely
used in these years for its advantage of wide spectrum, low working Signal-to-Noise
ratio (SNR), anti-interference, anti-multipath effect and capability of LPI and LPD.
They are increasingly replacing conventional communication forms and obtaining
extensively applications in modern military and commercial communication systems,
for example, CDMA communication system, GPS , measuring and control system,
satellite chain, identification of friend or foe and etc. Therefore, corresponding DSSS
electronic counter technique becomes a big problem to solve in electronic warfare
domain. DSSS electronic counter technique including blind detection, blind parameter
estimation and spreading sequences estimation. For the issue of DSSS electronic
counter technique of DSSS/QPSK signal damaged by strong additive white Gaussian
noise (AWGN), the main research content in this dissertation as follow.
Platform: |
Size: 2061312 |
Author:yangs |
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Description: 直序扩频通信系统仿真实例,信源为数字信号信道信噪比为10dB的直扩通信系统仿真实验simulik文件-Direct sequence spread spectrum communication system simulation example, the source for digital signal channel SNR for 10 db of spread spectrum communication system simulation simulik file Platform: |
Size: 87040 |
Author:LZ |
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Description: 建立了直接序列扩频系统的matlab仿真模型，在信道中存在高斯白噪声和干扰的情况下，对系统的在不同扩频增益下的误码率性能进行了仿真及分析，分析了扩频码的自相关性、误码率、性噪比。(A matlab simulation model of the direct sequence spread spectrum system, the existence of Gauss white noise and interference in the channel under the condition of the system in different spreading gain the BER performance of the simulation and analysis, analysis of PN code autocorrelation, BER, SNR) Platform: |
Size: 2048 |
Author:影0856
|
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Description: 5. 在三条径的瑞利信道中，对于直接序列扩频：
(1) 请设计DS-CDMA一种具体的码分导引辅助的信道估计方法，接收机分别采用等均益合并、最大比合并。用Simulink进行仿真，画出比特信噪比与信道估计均方误差的关系曲线和比特信噪比与误码率的关系曲线。
(2) 设频率已经同步，请设计DS-CDMA一种具体的单停顿滑动相关时间同步方法，用Simulink进行仿真，画出比特信噪比与捕获概率的关系曲线。
(3) 设时间已经同步，请设计DS-CDMA一种具体的频率同步方法，用Simulink进行仿真，画出比特信噪比与频率同步误差的关系曲线。(5. In three-path Rayleigh channel, for direct sequence spread spectrum:
(1) please design a specific code division navigation aided channel estimation method for ds-cdma, and adopt equal-beneficial combination and maximum ratio combination for receivers respectively.Simulink is used to simulate and draw the relationship curve between bit SNR and channel estimation mean square error and the relationship curve between bit SNR and bit error rate.
(2) assuming that the frequency has been synchronized, please design a specific single-stop sliding correlation time synchronization method ds-cdma, Simulink simulation, draw the relationship between the bit SNR and the acquisition probability curve.
(3) if the time has been synchronized, please design a specific frequency synchronization method ds-cdma, Simulink simulation, draw the relationship between the bit SNR and frequency synchronization error curve.) Platform: |
Size: 3554304 |
Author:kmdcdy |
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Search - spread spectrum SNR