The LZW compression class i mplemented as a fixed length code which you can specify, the huffman algorithm implementation encodes a byte into a variable length bit array. Both of them can work with streams
標簽： compression mplemented huffman specify
上傳時間： 2013-12-03
上傳用戶：yzhl1988
This program simulates the bit-error-rate (BER) performance of OSTBC with L=4 antennas over the frequency flat Rayleigh block fading channel The code is developed for real orthogonal design, code rate 1/2 modulation- 16 QAM with gray coding resulting in 2 bits/sec/Hz.
標簽： bit-error-rate performance simulates the
上傳時間： 2014-01-13
上傳用戶：whenfly
This project aim was to build wireless software modem for data communication between two computers using an acoustic interface in the voice frequency range (20Hz– 20,000Hz). The transmitting antenna is a speaker (frequency response of: 90Hz – 20,000Hz) and the receiving antenna is a microphone (frequency response of: 100Hz – 16,000Hz). The test files used as information files were text files. This goal was attained both in an incoherent scheme and in a coherent scheme. Build under Matlab code, our modem uses OFDM (orthogonal frequency division multiplexing) modulation, synchronization by LMS sequence, channel estimation (no equalizer) via pilot tones. The symbols are either PSK or ASK for a constellation size of 2 or 4. To optimize the probability of error, these symbols were mapped using Gray mapping. Report
標簽： communication computers software wireless
上傳時間： 2014-05-29
上傳用戶：wangdean1101
OFDM Modem Applications • Digital Video Broadcast (DVB) • Digital Audio Broadcast (DAB) • Broadband Wireless Access (802.16x) • Wireless LAN (802.11x & HiperLAN) Orthogonal OFDM Sub-carriers Orthogonal Frequency Division Multiplexing (OFDM)
標簽： Broadcast Digital 8226 Applications
上傳時間： 2016-03-23
上傳用戶：cc1
A digital fi‘equeney meter designed with FPGA development software Q-~us 11 is introduced．The 1 Hz—l MHz input measured pulse signals of the digital ii‘equency meter can be used for measuring frequency，period，pulse width and duty ratio，etc．The test results stably display O71 3 seven—segment numeric tubes，and the measuring ranges may be switched over automatically．The measuring error is equal to or less than 0．1％．
標簽： development introduced designed software
上傳時間： 2016-04-09
上傳用戶：stewart·
DFT(Discrete Fourier Transformation)是數字信號分析與處理如圖形、語音及圖像等領域的重要變換工具，直接計算DFT的計算量與變換區間長度N的平方成正比。當N較大時，因計算量太大，直接用DFT算法進行譜分析和信號的實時處理是不切實際的。快速傅立葉變換(Fast Fourier Transformation，簡稱FFT)使DFT運算效率提高1～2個數量級。其原因是當N較大時，對DFT進行了基4和基2分解運算。FFT算法除了必需的數據存儲器ram和旋轉因子rom外，仍需較復雜的運算和控制電路單元，即使現在,實現長點數的FFT仍然是很困難。本文提出的FFT實現算法是基于FPGA之上的，算法完成對一個序列的FFT計算，完全由脈沖觸發，外部只輸入一脈沖頭和輸入數據，便可以得到該脈沖頭作為起始標志的N點FFT輸出結果。由于使用了雙ram，該算法是流型(Pipelined)的，可以連續計算N點復數輸入FFT，即輸入可以是分段N點連續復數數據流。采用DIF(Decimation In Frequency)-FFT和DIT(Decimation In Time)-FFT對于算法本身來說是無關緊要的，因為兩種情況下只是存儲器的讀寫地址有所變動而已，不影響算法的結構和流程，也不會對算法復雜度有何影響。
標簽： Transformation Discrete Fourier DFT
上傳時間： 2016-04-12
上傳用戶：lx9076
// This program measures the voltage on an external ADC input and prints the // result to a terminal window via the UART. // // The system is clocked using the internal 24.5MHz oscillator. // Results are printed to the UART from a loop with the rate set by a delay // based on Timer 2. This loop periodically reads the ADC value from a global // variable, Result.
標簽： the measures external program
上傳時間： 2013-12-27
上傳用戶：trepb001
This example demonstrates how the C8051F06x SMBus interface can communicate // with a 256 byte I2C Serial EEPROM (Microchip 24LC02B). // - Interrupt-driven SMBus implementation // - Only master states defined (no slave or arbitration) // - Timer4 used by SMBus for SCL low timeout detection // - SCL frequency defined by <SMB_FREQUENCY> constant
標簽： demonstrates communicate C8051F06x interface
上傳時間： 2016-04-12
上傳用戶：hanli8870
在DAB系統中的頻率同步，載頻同步，參考一下Carrier frequency offset estimation of DAB receiver based on phase reference symbol
上傳時間： 2014-11-23
上傳用戶：songrui
// // Histogram Sample // This sample shows how to use the Sample Grabber filter for video image processing. // Conceptual background: // A histogram is just a frequency count of every pixel value in the image. // There are various well-known mathematical operations that you can perform on an image // using histograms, to enhance the image, etc. // Histogram stretch (aka automatic gain control): // Stretches the image histogram to fill the entire range of values. This is a "point operation," // meaning each pixel is scaled to a new value, without examining the neighboring pixels. The // histogram stretch does not actually require you to calculate the full histogram. The scaling factor // is calculated from the minimum and maximum values in the image.
標簽： Sample Histogram Grabber sample
上傳時間： 2013-12-15
上傳用戶：ryb
