Location:
Search - pseudo-noise
Search list
Description: 直接序列扩频通信可以有效地抵抗来自信道中的窄带干扰。在一个直扩通信系统中,扩频是通过伪噪声序列(PN)对发送的信息数据进行调制来实现的。在接收端,原伪噪声序列和所收信号的相关运算可将窄带干扰扩展到DS信号的整个频带,使干扰等效为幅度较低频谱较平坦的噪声；同时，将DS信号解扩,恢复原始信息数据。-direct sequence spread spectrum communication can be effective resistance from the channel narrowband interference. In a DSSS system. Spreading through the sequence of pseudo-noise (PN) to send the right message to data modulation to achieve. On the receiving end, the original pseudo-noise sequence and the received signal may be related Operational narrowband interference signal DS extended to the whole band, make tampering equivalent to a lesser extent than the flat spectrum of noise; Meanwhile, the DS signal disspreaded restore the original data.
Platform: |
Size: 111604 |
Author: 赵艳朝 |
Hits:
Description: 直接序列扩频系统是在发端直接用具有高码率的扩频编码去扩展信号的频谱，而在收端用相同的扩频编码进行解扩使扩频信号还原为原始信号的一种扩频方式。直接序列系统中用的编码序列通常是伪随机序列或叫伪噪声（PN）码。要传送的信息经数字化后变成二元数字序列，它和伪随机序列模二相加(或相乘)后变成复合码去调制载波。在直接序列系统中通常对载波进行二进制相移键控调制(BPSK)。当扩频调制后由天线发射出去，在接收机中要有一个和发射机中的伪随机码同步的本地码，对接收信号进行解扩，解扩后的信号送到解调器取出传送的信息-direct sequence spread spectrum system is the originator directly with the high rate of spread spectrum signal coding to the expansion of the spectrum, and the resumption end with the same spread-spectrum coding for despreading spread spectrum signal so that the original signal reverted to a spread-spectrum approach. Direct-sequence system used in the coding sequence is usually pseudo-random sequence, or a pseudo-noise (PN) code. To the transmission of digital information by the following figures into binary sequence, it, and pseudo-random sequence-two together (or multiplication) into a composite code modulation to Carrier. In the direct-sequence system usually right carrier for binary phase shift keying modulation (BPSK). When spread spectrum modulation after the antenna launched, in the
Platform: |
Size: 877 |
Author: 成兴 |
Hits:
Description: 产生伪随机噪声的MATLAB程序，在通信系统仿真可以用到-produce pseudo-random noise MATLAB procedures, the communications system simulation can be used
Platform: |
Size: 1024 |
Author: 郑研 |
Hits:
Description: 直接序列扩频通信可以有效地抵抗来自信道中的窄带干扰。在一个直扩通信系统中,扩频是通过伪噪声序列(PN)对发送的信息数据进行调制来实现的。在接收端,原伪噪声序列和所收信号的相关运算可将窄带干扰扩展到DS信号的整个频带,使干扰等效为幅度较低频谱较平坦的噪声；同时，将DS信号解扩,恢复原始信息数据。-direct sequence spread spectrum communication can be effective resistance from the channel narrowband interference. In a DSSS system. Spreading through the sequence of pseudo-noise (PN) to send the right message to data modulation to achieve. On the receiving end, the original pseudo-noise sequence and the received signal may be related Operational narrowband interference signal DS extended to the whole band, make tampering equivalent to a lesser extent than the flat spectrum of noise; Meanwhile, the DS signal disspreaded restore the original data.
Platform: |
Size: 111616 |
Author: 赵艳朝 |
Hits:
Description: M-file for simulating a QPSK transmitter by modulating with a pseudo random bit stream. A serial to parallel conversion of the pseudo random bit stream is performed with mapping of two bits per symbol. A cosine and sine carrier is configured and the I and Q symbols modulate these carriers. The I and Q carriers are combined and time and frequency domain plots are provided showing key waveforms at various positions in the QPSK transmitter.
-M-file for simulating a QPSK transmitter b y modulating with a pseudo random bit stream. A s erial to parallel conversion of the pseudo rand om bit stream is performed with mapping of two bi ts per symbol. A cosine and sine carrier is CBMs gured and the I and Q symbols Modulate these CARR IERS. The I and Q carriers are combined and a time nd frequency domain plots are provided showing key waveforms at various positions in the QPSK t ransmitter.
Platform: |
Size: 2048 |
Author: xiaoying |
Hits:
Description: 直接序列扩频系统是在发端直接用具有高码率的扩频编码去扩展信号的频谱，而在收端用相同的扩频编码进行解扩使扩频信号还原为原始信号的一种扩频方式。直接序列系统中用的编码序列通常是伪随机序列或叫伪噪声（PN）码。要传送的信息经数字化后变成二元数字序列，它和伪随机序列模二相加(或相乘)后变成复合码去调制载波。在直接序列系统中通常对载波进行二进制相移键控调制(BPSK)。当扩频调制后由天线发射出去，在接收机中要有一个和发射机中的伪随机码同步的本地码，对接收信号进行解扩，解扩后的信号送到解调器取出传送的信息-direct sequence spread spectrum system is the originator directly with the high rate of spread spectrum signal coding to the expansion of the spectrum, and the resumption end with the same spread-spectrum coding for despreading spread spectrum signal so that the original signal reverted to a spread-spectrum approach. Direct-sequence system used in the coding sequence is usually pseudo-random sequence, or a pseudo-noise (PN) code. To the transmission of digital information by the following figures into binary sequence, it, and pseudo-random sequence-two together (or multiplication) into a composite code modulation to Carrier. In the direct-sequence system usually right carrier for binary phase shift keying modulation (BPSK). When spread spectrum modulation after the antenna launched, in the
Platform: |
Size: 1024 |
Author: 成兴 |
Hits:
Description: 采用匹配滤波，实现伪码捕获功能，模块内部可以产生简单噪声来验证捕获性能(verilog)-Matched filter used to achieve pseudo-code capture functionality, the module can generate simple internal noise to verify the performance capture (verilog)
Platform: |
Size: 2673664 |
Author: 曹旸 |
Hits:
Description: 直接序列扩频Matlab程序
直接序列扩频通信可以有效地抵抗来自信道中的窄带干扰。在一个直扩通信系统中,扩频是通过伪噪声序列(PN)对发送的信息数据进行调制来实现的。在接收端,原伪噪声序列和所收信号的相关运算可将窄带干扰扩展到DS信号的整个频带,使干扰等效为幅度较低频谱较平坦的噪声；同时，将DS信号解扩,恢复原始信息数据。-Matlab procedures for direct sequence spread spectrum direct sequence spread spectrum communications can effectively resist the narrow-band interference from the channel. In a DSSS communication systems, spread spectrum pseudo-noise sequence through (PN) for sending information data modulation is achieved. At the receiving end, the original pseudo-noise sequence and the received signal related to computing can be extended to narrow-band interference signal DS the whole band, so interference is equivalent to a lesser extent than the flat spectrum of noise At the same time, the DS signal despreading and restore original information data.
Platform: |
Size: 1024 |
Author: 周一 |
Hits:
Description: 在加密系统中,伪噪声序列(即PN序列)得到了广泛的应用,最常用的PN序列是最大长度线性码序列,又称为m序列,是由线性反馈移位器产生的,其特点是具有周期性和伪随机性。-In the encryption system, the pseudo-noise sequence (ie, PN sequence) is widely used, the most common PN sequence is the maximum length linear sequences, also known as m sequences, by the linear feedback shift generated, its characterized by periodic and pseudo-randomness.
Platform: |
Size: 1024 |
Author: 罗 |
Hits:
Description: 伪随机码发生器的VHDL实现
随着通信理论的发展，早在20世纪40年代，香农就曾指出，在某些情况下，为了实现最有效的通信，应采用具有白噪声的统计特性的信号。另外，为了实现高可靠的保密通信，也希望利用随机噪声。然而，利用随机噪声最大困难是它难以重复产生和处理。直到60年代，伪随机噪声的出现才使这一难题得到解决-Pseudo-random code generator for VHDL realize communication with the development of the theory, as early as the 20th century, 40 years, Shannon has pointed out that in some cases, in order to realize the most effective communications, should be used with the statistical properties of white noise signal . In addition, in order to realize highly reliable secure communication, but also wish to take advantage of random noise. However, the use of random noise the greatest difficulty is that it difficult to repeat the generation and treatment. Until 60 years, the emergence of pseudo-random noise so that this problem only be solved
Platform: |
Size: 217088 |
Author: 张之晗 |
Hits:
Description: Simulink pseudo-random binary sequence generator
Platform: |
Size: 44032 |
Author: 何必文 |
Hits:
Description: verilog实现awgn信道噪声的代码，支持可变的信噪比。利用移位寄存器来实现伪随机序列。-verilog code for implementation of awgn channel noise. support variable snr. use LSFR to implement the pseudo random sequence.
Platform: |
Size: 10555392 |
Author: xiejin |
Hits:
Description: 伪随机码或称PN码，是扩频通信中不可缺少的一种序列。扩频通信，简单的说来就是通过一组相关性很强的伪随机序列，使原有的信号按照伪随机序列的特性出现。从波形上看，原有信号完全淹没于随机的噪声中，达到隐藏信号和抗干扰的目的。接受方只要有相同的伪随机序列，就可以通过伪随机序列很强的相关性将信号还原出来。而m序列，是扩频系统中最长用的伪随机序列。下面的代码就是基于matlab的生成m序列的代码，通过改变初始多项式的值，就可以生成不同阶数的m序列。-Pseudo-random code or PN code, spread spectrum communication is indispensable to a sequence. Spread spectrum communication, a simple to say that the adoption of a group of highly related to pseudo-random sequence, so that the original signal in accordance with the characteristics of pseudo-random sequence there. From the wave point of view, the original signal completely submerged in the random noise to hide the purpose of signal and interference. As long as the recipient has the same pseudo-random sequence, the pseudo-random sequence can be a strong correlation to restore the signal out. And m sequence spread spectrum system is the longest of the pseudo-random sequence used. The following code is generated based on m sequences of matlab code, by changing the value of the initial polynomial, we can generate a different order of the m sequence.
Platform: |
Size: 1024 |
Author: fortunewjh0217 |
Hits:
Description: 包括图像输入（打开文件、采集、捕捉图像、从剪贴板粘贴、打开扫描软件、灰度化、添加随机噪声、椒盐噪声、去噪声）、图像处理（几何变换、灰度反转、直方图均衡化、直方图统计、图像复原、边缘提取、伪彩色、二值化、图像变换）、图像输出（另存图像、打印输出、复制到剪贴板）-Including image input (open the file, capture, capture images, paste from the clipboard, open the scanning software, graying, adding random noise, Salt and pepper noise, to noise), image processing (geometric transformation, gray inversion, histogram equalization oriented, histogram statistics, image restoration, edge extraction, pseudo-color, binary, image transform), image output (save the image, print out, copy to clipboard)
Platform: |
Size: 470016 |
Author: 沉浮沉 |
Hits:
Description: pseudo noise time hopping simulation
Platform: |
Size: 8192 |
Author: ragdog86 |
Hits:
Description: 基于不变矩理论，提出一种应用概率神经网络作为识别器的车牌汉字识别技术。利用Pseudo-Zernike 矩特征的旋转不变性和良好
的抗噪性能，将其作为车牌汉字识别的特征矢量，结合Pseudo-Zernike 矩的快速算法和概率神经网络识别器快速学习和识别的性能，可适
应实时环境下所获取的车牌汉字灰度图像的识别，具有较高的准确率，实验结果表明了该方法的有效性。-】This paper presents a novel approach based on Pseudo-Zernike Invariant Moments(PZIM) and Probabilistic Neural Network(PNN) to
recognize license plate Chinese characters. The approach makes better use of the rotation invariant and good anti-noise performance of
Pseudo-Zernike moments and quick learning rate of PNN, and thus provides a real-time recognition of gray character images by utilizing
Pseudo-Zernike moments as feature vectors and Probabilistic Neural Network as classifier. Numeral experiment confirms that it is an effective way
to classify license plate Chinese characters.
Platform: |
Size: 1236992 |
Author: ll |
Hits:
Description: here is the maltlab file of pseudo noise generation
Platform: |
Size: 1024 |
Author: Ankit |
Hits:
Description: PN_GEN: This is a matlab function generates the Pseudo Noise sequnece of length (N)according to Generation Polynom and input state.
Inputs: G - Generation Polynom, Zin - Initial state of Shift register N - The length of PN sequence
Outputs: y - The resulting PN sequence
Z - The output state of Shift register
Platform: |
Size: 2048 |
Author: Roshdy |
Hits:
Description: 自己写的用matlab实现的无噪声程序，包含随机产生信号，然后增加伪随机代码，最后修正信号的过程。-Using matlab to achieve their own written procedures for noise-free, contains randomly generated signals, and then increase the pseudo-random code, last amended signals.
Platform: |
Size: 7168 |
Author: |
Hits:
Description: 产生白噪声序列- Generate a pseudo-noise
Platform: |
Size: 1024 |
Author: wd |
Hits: