Description: 函数通过输入信号序列和函数序号，以及调制解调选择参数来完成扩频调制解调。original_seq是原始输入序列，可能是未调制序列，也可能是调制序列，walsh_num是walsh函数的序号，select选择对输入的序列进行调制还是解调。-function through the input signal sequence and function of the serial number and choice of modulation and demodulation parameters to complete spread spectrum modulation and demodulation. Original_seq is the original input sequence may not be modulated sequence, and may also be modulated sequence, walsh_num walsh function of the serial number, select choice of input sequence modulation or demodulation. Platform: |
Size: 880 |
Author:刘洪 |
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Description: 函数通过输入信号序列和函数序号，以及调制解调选择参数来完成扩频调制解调。original_seq是原始输入序列，可能是未调制序列，也可能是调制序列，walsh_num是walsh函数的序号，select选择对输入的序列进行调制还是解调。-function through the input signal sequence and function of the serial number and choice of modulation and demodulation parameters to complete spread spectrum modulation and demodulation. Original_seq is the original input sequence may not be modulated sequence, and may also be modulated sequence, walsh_num walsh function of the serial number, select choice of input sequence modulation or demodulation. Platform: |
Size: 1024 |
Author:刘洪 |
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Description: 摘要本文首先分析了自适应调制的原理, 它以频谱效率最高为准则, 在恒定功率约束条件下对接收信噪
比优化来选择不同调制阶数。然后引入时变多径信道模型, 通过仿真给出了自适应在此信道条件下的性能, 并分析
了信道估计误差对其性能的影响。
关键词自适应调制, 调制, 时变信道-Abstract This paper first analyzes the principle of adaptive modulation, spectral efficiency it up to standards, in the constant power constraint condition to receive a letter under the noise
Optimization to select different modulation than the order of. Then the introduction of time-varying multi-path channel model is given by simulation of adaptive channel conditions in this performance, and analyze the
The channel estimation error on their performance.
Key words adaptive modulation, modulation, time-varying channel Platform: |
Size: 167936 |
Author:yanyan |
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Description: 利用MAXPLUS作为仿真工具，用VHDL语言编程，采用频率键控法实现3FSK调制。对输入的系统时钟分别进行2分频，4分频和8分频得到这3种频率。通过对数字基带信号进行双二进制编码得到3个电平值，把它们作为三选一开关，来分别选择不同的频率值、选择不同的信号，从而实现3FSK调制。-As a simulation tool used MAXPLUS using VHDL language programming, using frequency shift keying modulation method to achieve 3FSK. The input of the system clock frequency respectively 2 hours, 4 minutes and 8 frequency-divider to have these three kinds of frequencies. Through the digital baseband signals received three pairs of binary-coded level value, and use them as three elected a switch to a different frequency values were selected, select a different signal, in order to achieve 3FSK modulation. Platform: |
Size: 4096 |
Author:雷月 |
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Description: 调频发射机，(1) 在发射频率范围内，预置5个频率点，用手动方式选择其中一个发射
(2) 进一步提高通信距离；
(3) 调制失真不大于10
(4) 10.(4)其他特色与创新。
-FM Transmitter, (1) in the firing frequency range, the preset frequency of 5 points manually select one of the launch (2) further enhance the communication distance (3) modulation distortion is less than 10 (4) 10 . (4) other characteristics and innovation. Platform: |
Size: 5120 |
Author:梁蛟龙 |
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Description: 这是关于LDPC信道编码模块设计的程序
打开源程序，先运行gengrate_h.m程序，陆续将码长设置为756bit，列重设置为3，行重设置为9。在Workspace中同时将H、A、B、C、D、E、Hget、Fget、g、Tget这是个变量选择另存为encode_in.mat 格式。再运行main_encode.m进行编码，主程序运行后，在当前目录下，自动生成编码结果文件“encode—out.mat”，这将作为下一次扩频调制仿真实验的的输入信号。最后分别查看Workspace中的变量s（编码前数据）和xyuan（编码后数据）的波形。
对比后，可以看出编码前的数据码片长度为504bit，编码后的码片数据长度为756bit。编码效率=编码前码片长度/编码后码片长度=2/3。-This is about the LDPC channel coding module design process
Open source, first run gengrate_h.m program, phasing out the code length is set to 756bit, column re-set to 3, line weight is set to 9. In the Workspace in the same time, H, A, B, C, D, E, Hget, Fget, g, Tget This is a variable select Save As encode_in.mat format. Then run main_encode.m encoding, the main program running in the current directory, the results of automatically generated code file "encode-out.mat", which will serve as the next simulation of the spread spectrum modulation input signal. Finally, the variables were View Workspace in s (before encoding data) and xyuan (encoded data) waveform.
After comparison, we can see the data before encoding chip length of 504bit, encoded data length of chip 756bit. Coded before coding efficiency = chip length/length of the encoded chip = 2/3. Platform: |
Size: 15360 |
Author:吴健 |
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Description: 给出了不同分割数量V条件下的系统的PAPR性能，分割方法为随机分割，辅助相位集合的相位数P=4(即 可选择的范围为{0,π/2,π,3π/4})，N=128，子载波采用QPSK调制，仿真的OFDM符号数为1000个。-V gives the number of different partitions of the system under PAPR performance of random segmentation segmentation, the number of secondary phase of the phase set P = 4 (to select the range {0, π/2, π, 3π/4} ), N = 128, sub-carrier using QPSK modulation, simulation of the OFDM symbol number 1000. Platform: |
Size: 1024 |
Author:宫约 |
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Description: 在 OFDM 数学原理和收发模型的基础上，本文对帧同步、定时同步、频率同
步和采样同步给 OFDM 系统所产生的影响进行了理论分析，同时讨论了基于循环
前缀或训练符号的典型 OFDM 同步算法。参考 802.11a 突发数据帧结构和系统参
数，分析几种 OFDM 同步算法用于突发分组传输的性能；在分析了几种经典的信
道估计算法基础上,通过对复杂度和性能的折衷，选择一种适合本文系统的估计
算法。最后作者提出一种改进型 LS 信道估计算法，该算法考虑了 LS 算法中噪声
的影响，从而提高了低信噪比下信道估计的精度。仿真结果表明，改进算法在低
信噪比下具有良好的性能。
-OFDM mathematical principles and transceiver model based on frame synchronization, timing synchronization, frequency synchronization and sampling synchronization to the OFDM system, the impact of the theoretical analysis are also discussed based on the cyclic prefix or training symbols typical OFDM synchronization algorithm . Reference 802.11a burst data frame structure and system parameters, analyze several OFDM synchronization algorithm for burst packet transmission performance several classic channel estimation algorithm based on a compromise between complexity and performance, select a suitable estimation algorithm in this article. Finally, the author proposed a modified LS channel estimation algorithm that takes into account the effects of noise in the LS algorithm, thus improving the low SNR channel estimation accuracy. Simulation results show that the improved algorithm has good performance in low signal-to-noise ratio. Platform: |
Size: 8734720 |
Author:刘金强 |
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Description: Pulse code modulation is a form of information conversion from discrete to digital. Pulse code modulation is used in almost all modern communication systems and is essential for digital communication. Each sampled value is given in the form of a discrete signal, converted to its binary equivalent, and coded in the form of zeros and ones. There are different types of pulses used for coding ones and zeros. In the following program the user is asked to select the pulse which will then be used to modulate the incoming digital signal. Platform: |
Size: 26624 |
Author:Ritesh Das |
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Description: 本章在分析PMSM DTC系统存在的转矩和磁链脉动问题的基础上，深入研究了一种新型的控制方法，就是把磁链的扇区进行细分，仿真结果表明，在采用扇区细分控制策略以后，PMSM DTC能够获得良好的动态性能，转矩脉动问题也显著的减小-In the traditional direct torque control system,the system can produce torque ripple for that the system has margins of error in observation of stator flux position and the inverter switching frequency is not fixed.To solve this problem, this paper studies the control scheme based on flux observation error,which combine the voltage space vector pulse width modulation technology with direct torque technology.Voltage space vector selection of arbitrary phase and amplitude of the flux and torque,We can select Voltage space vector in arbitrary phase and amplitude by Error of the flux and torque so that torque ripple can reduce.The simulation results show that this control strategy is feasible, and the new PMSM DTC system is superior to the conventional one. Platform: |
Size: 18432 |
Author:史晓永 |
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Description: OFDM simulation system use different modulation technique such as M-PSK M-QAM
user can select that type . the program use image to be transmitted in QI mapped ,signal affected by AWGN and Fading on channel be for received Platform: |
Size: 87040 |
Author:captain_universe
|
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Description: 信号调制识别程序，可以在菜单里选择输入的信号类型，经识别后显示。(The signal modulation recognition program can select the type of input signal in the menu and display it after recognition.) Platform: |
Size: 2048 |
Author:legend27 |
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Search - modulation select