Description: 此源码是用DSP实现QPSK调制，在CCS软件上实现．采样速率为14400样点／s，载波频率为1800Hz,带宽为300～3300Hz，符号速率为2400符号／s，滚降系数为0.35．-this source is used DSP QPSK modulation, the CCS software to achieve. Sampling rate of 14,400 samples/s, the carrier frequency of 1800 Hz. bandwidth of 300-3300Hz, Symbol rate of 2,400 symbols/s, roll-off factor of 0.35. Platform: |
Size: 2048 |
Author:钟金 |
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Description: QPSK modulation system with recover loops-This is a model of a QPSK modulation system for transmission over a bandpass channel with fc = 100 Hz and B = 30 Hz and AWGN at the receiver. SRRC fi lters with excess bandwidth α = 0.18 are employed. The receiver includes an NDA timing recovery loop followed by a DD phase recovery loop. The transmitter?s symbol period is T and set to a value of 100 ms. The symbol period at the receiver is Tr. The model will produce six windows: Two constellation plots and two eye diagrams (for the real part only), at the output of the matched fi lters and after the recovery loops a plot of the phase error (output of the NCO) and a plot of the fractional timing error (used in the interpolator). The frequency off set at the receiver is denoted by deltaf. The model simulates the transmission of 8000 QPSK symbols. Platform: |
Size: 15360 |
Author:ranbowang |
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Description: 基于硬件定点的完整的costas载波恢复环设计，FPGA设计可以用之参考。包括输入QPSK信号，16倍符号率采样，初始频差2.4KHz，以及低通滤波器的设计等待。最重要的是有本人的注释，易于上手。-Hardware-based fixed-point of complete costas carrier recovery loop design, FPGA reference design can be used. Including input QPSK signal, 16 times the symbol rate sampling, the initial frequency difference 2.4KHz, and the design of low-pass filter to wait. The most important thing is to have my notes, easy to fly. Platform: |
Size: 2048 |
Author:luoshuwen |
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Description: This a thesis about CARRIER FREQUENCY OFFSET RECOVERY FOR ZERO-IF OFDM RECEIVERS.rar. The zero intermediate
frequency receiver architecture has now become popular as it has both economic and
size advantages over the traditional superheterodyne architecture.-This is a thesis about CARRIER FREQUENCY OFFSET RECOVERY FOR ZERO-IF OFDM RECEIVERS.rar. The zero intermediate
frequency receiver architecture has now become popular as it has both economic and
size advantages over the traditional superheterodyne architecture. Platform: |
Size: 1097728 |
Author:Kingfoo |
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Description: In this paper, a novel demodulation structure in
high-frequency (HF) channel is introduced and studied.Frequency-offset estimation, ractionally spaced adaptive equalization and carrier recovery techniques are involved.Frequency-offset correction is carried out based on channel impulse response estimation. ractionally spaced adaptive equalization and carrier recovery are combined with nonlinear decision feedback loop structure and the initial value
of tap coefficients of equalization are obtained from the previous channel estimation. Simulation is conducted under channel parameters with respect to MIL-STD-188-110B using a Monte Carlo technique. The results show this novel demodulation structure is feasible and efficient in HF channel, the symbol error ratio can reach to 10− 3 in 12dB SNR.-In this paper, a novel demodulation structure in
high-frequency (HF) channel is introduced and studied.Frequency-offset estimation, ractionally spaced adaptive equalization and carrier recovery techniques are involved.Frequency-offset correction is carried out based on channel impulse response estimation. ractionally spaced adaptive equalization and carrier recovery are combined with nonlinear decision feedback loop structure and the initial value
of tap coefficients of equalization are obtained from the previous channel estimation. Simulation is conducted under channel parameters with respect to MIL-STD-188-110B using a Monte Carlo technique. The results show this novel demodulation structure is feasible and efficient in HF channel, the symbol error ratio can reach to 10− 3 in 12dB SNR. Platform: |
Size: 186368 |
Author:Lin |
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Description: 数字基带信号的传输是数字通信系统的重要组成部分。在数字通信中，有些场合可不经过载波调制和解调过程，而对基带信号进行直接传输。采用AMI码的信号交替反转，有可能出现四连零现象，这不利于接收端的定时信号提取。而HDB3码因其无直流成份、低频成份少和连0个数最多不超过三个等特点，而对定时信号的恢复十分有利，并已成为CCITT协会推荐使用的基带传输码型之一。为此，本文利用VHDL语言对数据传输系统中的HDB3编码器进行了设计。
基于达到达到达到的信号发生器的源程序-Digital baseband signal transmission is a digital communications system, an important component. In digital communication, there are some occasions, may from time through the carrier modulation and demodulation process, the base-band signal for direct transmission. AMI code signal using alternating inversion, there may be four to zero with the phenomenon, which is not conducive to the receiving end of the timing signal extraction. The HDB3 code because of its non-DC components, low-frequency components, and even a small number of 0 up to more than three characteristics, while the timing signal recovery is very favorable, and has become CCITT Association recommended one of baseband transmission pattern. In this paper the use of VHDL language for data transmission system in the HDB3 encoder has been designed. Based on the signal generator to achieve to reach to reach the source Platform: |
Size: 3072 |
Author:成风 |
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Description: 通过分析8PSK 调制方式的载波恢复、定时恢复算法, 提出了一种适用于新一代数字卫星电视标准DVB S2
的全数字解调算法, 改进了相位频率检测( PFD) 算法以适合于8PSK 解调. 载波恢复采用频率检测( FD) 和相位频率
检测相结合的结构, 跟踪范围超过1 倍符号率. 采用Gardner TED 算法进行定时恢复.-By analyzing the 8PSK modulation carrier recovery, timing recovery algorithm is proposed for a new generation of digital television standard DVB S2 Satellite all-digital demodulation algorithm, improved phase-frequency detector (PFD) algorithm for 8PSK demodulation . carrier recovery using frequency detection (FD) and phase-frequency detector combined structure, tracking more than 100 times the symbol rate range. using Gardner TED algorithm timing recovery. Platform: |
Size: 199680 |
Author:赵亮 |
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Description: PSK31 Model with Symbol Timing and Carrier Recovery-This model implements a communication standard known as PSK31. The transmit portion of the model can either synthesize the PSK31 signal, or use real world signals that were captured as Wave files.
The receiver features include: Automatic Frequency Control, Automatic Gain Control, Symbol Timing recovery with a fractionally spaced Farrow interpolator, Decision Directed Carrier Phase Lock Loop, dbsk or dqpsk demodulation with FEC.
References are provided in the Model. Platform: |
Size: 954368 |
Author:刘建国 |
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Description: 该文采用数字科斯塔斯环并结合数字匹配滤波辅助捕获的方法对T DRSS 中的大多普勒频移进行捕获和消除, 解决了大多普勒情况下载波恢复的难题, 为工程实践提供了一种新思路。-In this paper, using a digital Costas loop in combination with the digital matched filtering auxiliary capture the T-DRSS large Doppler frequency shift to capture and eliminate to solve the problem of recovery of large Doppler downloaded for engineering practice provides a new ideas. Platform: |
Size: 236544 |
Author:jing |
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Search - carrier frequency recovery