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 |
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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 |
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Description: 直接序列扩频通信中PN码同步技术的研究，对于研究伪随机序列和扩频通信的人很有帮助哦、-Direct sequence spread spectrum PN code synchronization communication technology, the study of pseudo-random sequence spread spectrum communication and people very helpful Oh, Platform: |
Size: 84992 |
Author:caidan |
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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 |
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Description: 实现产生伪随机序列的部件 —— 线性反馈移位寄存器单元。 SFlog2为扩频因子的底数为2的对数值，cycle为PN序列的周期，其值为2^SFlog2。initial_state为移位寄存器的初始状态，generator_polynomial_coefficient为生成PN序列所需的本原多项式，对应于移位寄存器的连接向量。-The realization of pseudo-random sequence generated components- LFSR unit. SFlog2 factor for the spread-spectrum base 2 of value, cycle for the PN sequence cycle, its value is 2 ^ SFlog2. initial_state shift register for the initial state, generator_polynomial_coefficient to generate the necessary PN sequence primitive polynomial, corresponding to the shift register connection vector. Platform: |
Size: 1024 |
Author:fisher |
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Description: 产生PN序列，及产生伪随机序列,可用于数字水印扩频等-Generated PN sequence, and generate pseudo-random sequence, spread spectrum can be used for digital watermarking, etc. Platform: |
Size: 78848 |
Author:zhengyun |
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Description: 扩频通信系统，包括直接序列扩频，PN序列产生，以及调频扩频-Spread spectrum communication system, including direct sequence spread spectrum, PN sequence generation, as well as spread spectrum frequency modulation Platform: |
Size: 7168 |
Author:廖洪运 |
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Description: 本程序可生成直接序列扩频中所需的PN伪码m序列和golden序列-This procedure can be generated in direct sequence spread spectrum PN code required PN sequence and golden sequence m Platform: |
Size: 1024 |
Author:huangyi |
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Description: 该程序仿真了混沌序列与传统pn序列的扩频系统误码性能。-Simulation of the process of chaotic sequence with the traditional pn sequence spread spectrum system BER. Platform: |
Size: 3072 |
Author:李巍 |
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Description: The .m file simulates a Spread-Spectrum Modulation Trx/Rcx system, in which, the phase of the pseudo-random sequence generated in the transmitter and used to encode the data stream is unknown a priory at the receiver.A parallel search strategy is employed to locally determine it in the place. It works as here: selecting the maximam-energy low-pass filtered signal of the set of all hypothesied despreaded ones using different hypothesized phases for the PN-sequence.The simulation can be growed in several ways including considering various types of noise and jammings or also designing better filters. Platform: |
Size: 3072 |
Author:Rafal |
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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 |
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Description: 带干扰的直接序列扩频通信系统,PN码由m序列产生器产生，经过高斯白噪声信道。在接收端接收到的信号包括“有用信号+高斯白噪声+干扰”，将接收信号进行解扩，判决，得到用户的信号检测结果，绘制不同的扩频增益（增益值为10，30，50）下，误比特率随信噪比Eb/N0的变化曲线。-the direct sequence spread spectrum with interference communication system Platform: |
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Author:ailj |
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Description: 设计一个有干扰的直接序列扩频通信系统， PN码由m序列产生器产生，经过高斯白噪声信道。在接收端接收到的信号包括“有用信号+高斯白噪声+干扰”，将接收信号进行解扩，判决，得到用户的信号检测结果，绘制不同的扩频增益（增益值为10，30，50）下，误比特率随信噪比Eb/N0的变化曲线。-Design of a direct sequence spread spectrum interference system, PN code generated by the m sequence generator, after white Gaussian noise channel. Receives the signal at the receiver, including " useful signal+ Gaussian white noise+ interference" , will receive the signal despreading, judgments, get the user' s signal test results, draw a different spreading gain (gain value of 10,30, 50), the BER curves with the signal to noise ratio Eb/N0. Platform: |
Size: 7168 |
Author:皓月 |
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Description: 文章中主要阐述了PN码的捕获，并对以前的各种捕获方法进行了改进。得出了基于FFT的快速捕获算法！-Abstract-A FFT-based parallel acquisition algorithm for Direct
Sequence/Spread Spectrum radio navigation system is studied to
solve long PN code acquisition using serial method. Frequency
domain analysis of FFT to acquire signal is applied in this paper
and state transfer function is used to derive the expression of
average acquisition time. Platform: |
Size: 553984 |
Author:严鹏涛 |
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Description: 本文算法是将24 位真彩图的亮度分量分块
DCT ,然后利用DCT 量化系数的奇偶特性嵌入8
位灰度水印图,并通过PN 序列加密来保证水印的
安全性。算法中,将灰度图像转换为二进制数据
流,置乱后扩频调制,隐藏在宿主DCT 系数量化值
中,提取时不需要宿主信号,实现水印信号的盲提
取。-This algorithm is 24-bit true color pictures of the luminance component of block DCT, quantization DCT coefficients and then use the parity properties of 8-bit grayscale watermark embedding map, and through the PN sequence of encryption to ensure the security of the watermark. Algorithm, the gray image into binary data stream, scrambling after the spread spectrum modulation, hidden in the host DCT coefficient quantization values, the extraction does not require the host signal, the blind watermark extraction. Platform: |
Size: 284672 |
Author:王秀梅 |
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Description: 本程序可生成直接序列扩频中所需的PN伪码m序列和golden序列.-The program can generate the required direct sequence spread spectrum PN sequence and golden pseudo-code sequence m Platform: |
Size: 1024 |
Author:Poul |
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Description: 本程序可生成直接序列扩频中所需的PN伪码m序列和golden序列。-The program can generate the required direct sequence spread spectrum PN sequence and golden pseudo-code sequence . Platform: |
Size: 2048 |
Author:Poul |
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Search - spread spectrum PN sequence