Description: The basic parts of the BFSK transmitter are the preamble and the data input circuit. The preamble sequence is positioned in front of each packet of 122 bits for a total of 128 bits packet. The main purpose of the preamble is to facilitate the reception, providing both bit and packet synchronization. The data input circuit mainly consists from memory elements and a convolutional encoder with r=1/2. Thus, the input bits must be stored in a temporary memory and be partitioned in blocks of 61 bits. Then the convolutional encoder doubles the bits and adds two more trail bits at the end of the message. A multiplexer makes sure that that the correct sequence, choosing between preamble and encoded bit, is propagating to the next stage. The next stage of the transmitter consists of two direct digital synthesizers (DDS), and a multiplexer that is fed with zeros and ones to choose between the two frequencies. For each bit, we allow 64 samples of the respective frequency to be transmitted. Although the implementation of the selection between the two frequencies is strait forward, the enable port of the multiplexer should be used along with a Matlab Code (MCode) block in order to prevent the propagation of some initial undefined states during initialization. The only functionality of the MCode block is to enable the multiplexer after the first bit of the preamble is detected. Finally, pulse shaping is not used and the addition of a single filter after the last multiplexer would suffice to implement this functionality. Platform: |
Size: 31381 |
Author:publicxz |
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Description: 卷积码是一种有记忆的编码，在任意给定的时间单元处，编码器的n个输出不仅与此时间单元的k个输入有关，而且也与前m个输入有关。卷积码通常表示为：（n,k,m）
本次仿真采用（2，1，3）卷积码。
-convolutional code is a kind of code memory, in any given unit of time, the encoder output n this time not only with the elements of the k input, but also with the input m. Convolutional codes are usually stated as : (n, k, m), the simulation used (2,1,3) convolutional code. Platform: |
Size: 3072 |
Author:yx |
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Description: 强烈推荐好用的卷积码编码，维特比译码和软判决，本代码简易可行。-Strongly recommend use of the convolutional code encoder, Viterbi decoder and soft decision, the code simple and feasible. Platform: |
Size: 3072 |
Author:胡卓 |
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Description: Computes BER v EbNo curve for convolutional encoding / soft decision
Viterbi decoding scheme assuming BPSK.
Brute force Monte Carlo approach is unsatisfactory (takes too long)
to find the BER curve.
The computation uses a quasi-analytic (QA) technique that relies on the
estimation (approximate one) of the information-bits Weight Enumerating
Function (WEF) using
A simulation of the convolutional encoder. Once the WEF is estimated, the analytic formula for the BER is used.-Computes BER v EbNo curve for convolutional encoding/soft decision Viterbi decoding scheme assuming BPSK. Brute force Monte Carlo approach is unsatisfactory (takes too long) to find the BER curve.The computation uses a quasi-analytic (QA) technique that relies on theestimation (approximate one) of the information-bits Weight Enumerating Function (WEF) usingA simulation of the convolutional encoder. Once the WEF is estimated, the analytic formula for the BER is used. Platform: |
Size: 6144 |
Author:joy |
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Description: simulating a convolutional encoder
allows the user to input a source code to be encoded and also input the values of the generator polynomials. It outputs the encoded data bits, where 1/n is the code rate Platform: |
Size: 1024 |
Author:郑中 |
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Description: Generate trellis data of a rate-1/n convolutional encoder.卷积码1/n的编码器，注意生成的是非系统码。-Generate trellis data of a rate-1/n convolutional encoder. Convolutional codes 1/n of the encoder, the attention generated by the non-system code. Platform: |
Size: 4096 |
Author:戈津生 |
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Description: 卷积码的MATLAB实现，包括编码器和译码器。-Convolutional codes of MATLAB to achieve, including the encoder and decoder. Platform: |
Size: 580608 |
Author: |
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Description: convolenc -performs convolutional encoding
Convolutional Encoder with m shift register stages
x- input - the binary data to be encoded
input sequence can be of any length
k -constraint length
k can take any value greater than 3
m -number of shift registers
L -size of the input array
returns encoded bits - convolenc -performs convolutional encoding
Convolutional Encoder with m shift register stages
x- input- the binary data to be encoded
input sequence can be of any length
k-constraint length
k can take any value greater than 3
m-number of shift registers
L-size of the input array
returns encoded bits Platform: |
Size: 1024 |
Author:ade |
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Description: Viterbi decoder for nonsystematic convolutional code. The encoder could be designed arbitrary through the generate matrix and parameter k. The number of row of generate matrix is output bits, and collom is constraint length. Parameter k is the number of parallel input. test.m is the main file. Platform: |
Size: 3072 |
Author:studenter |
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Description: 本设计选取CDMA通信系统中的接入信道部分进行仿真与分析。首先，通过学习相应的理论知识，熟悉接入信道实现的过程，对每一步的原理有了较深的理解，同时，也对MATALB软件进行熟悉和了解，对MATLAB软件中的SIMULINK部分及其内部的CDMA模块用法和参数设置进行熟悉，然后运用MATLAB软件对接入信道部分进行设计，并逐步地对各个模块进行分析、仿真与验证。目的是通过毕业设计工作熟悉现代无线通信系统的基本构成与基本工作原理，重点掌握卷积编码、块交织和码扩展等相关编码技术，并能将这些技术应用实际系统设计，提高自己对CDMA通信系统知识的认识。-This design choose the part of connect channel to simulate and analyse. First,we can familiar with the process of connect channel ,understand the principleof every step of the procedure about thre channel,after studying the relating knowledge .At the same time ,we an also have some acquaintance with the software about MATLAB and the part of SIMULINK and how to set the parameter of every klock in the soft.Then we can use the MATLAB software to design the part of the connect channel, to analyse , to simulate and to validate the design of every block gradually. This purpose is to be familiar with the basic structure and basic principle of the morden wireless communication system, to mastery the technology about the Convolutional Encoder,Interleaver ,Coder spread and so forth, then use those technology to design system in practice,so that to improve our knowledge about the CDMA communication system. Platform: |
Size: 354304 |
Author:xxxmmmccc |
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Description: Its a convolutional encoder with code rate of 1/2 and constraint length of 3.
i/p=1 bit
o/p=2 bits with 4 memory elements Platform: |
Size: 480256 |
Author:Adnan |
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Description: this is a Simulation s of matlab for convolutional Encoder.
in it s result you will see plots for convolutional encoder and decoder.there is also two .jpg files that show the schematic of decoder and encoder. Platform: |
Size: 3072 |
Author:hossein |
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Search - convolutional encoder matlab