Abstract-The effect of the companding process on QAM signals has been under investigation for the past several years. The compander, included in the PCM telephone network to improve voice performance, has an unusual affect on digital QAM data signals which are transmitted over the same channel. The quantization NOISE, generated by the companding process which is multiplicative (and asymmetric), degrades the detectability performance of the outermost points of the QAM constellation more than that of the inner points. The combined effect of the companding NOISE and the inherent white gaussian NOISE of the system, leads us to a re-examination of signal constellation design. In this paper we investigate the detectability performance of a number of candidates for signal constellations including, a typical rectangular QAM constellation, the same constellation with the addition of a smear-desmear operation, and two new improved QAM constellation designs with two-dimensional warpi
標簽： investigation Abstract-The companding the
上傳時間： 2013-12-20
上傳用戶：英雄
ofdm信道特性 Channel transmission simulator Channel transmission simulator ％ ％ inputs: ％ sig2 - NOISE variance ％ Mt - number of Tx antennas ％ Mr - number of Rx antennas ％ x - vector of complex input symbols (for MIMO, this is a matrix, where each column ％ is the value of the antenna outputs at a single time instance) ％ H - frequency selective channel - represented in block-Toeplitz form for MIMO transmission ％ N - number of symbols transmitted in OFDM frame ％ ％ outputs: ％ y - vector of channel outputs (matrix for MIMO again, just like x matrix) ％ create NOISE vector sequence (each row is a different antenna, each column is a ％ different time index) note: NOISE is spatially and temporally white
標簽： transmission simulator Channel inputs
上傳時間： 2016-07-22
上傳用戶：kelimu
數字信號處理基于matlab 文件內容 /conv(卷積部分) dupconv 重疊保留法 freqcirconv 頻域圓周卷積 freqconv 頻域卷積 timecirconv 時域圓周卷積 timeconv 時域卷積 /fft(頻域分析部分) d2fft 基2FFT dft DFT最簡化程序 dtft DTFT演示 /fir(fir濾波器設計) fir 得到fir濾波器hn getwindow 得到fir濾波器窗函數wn idealfilter 理想濾波器(低通,高通,帶通)hdn idealhd 理想低通濾波器 /fir gui(fir濾波器GUI設計) gui_top 總圖 gui_fir fir濾波器GUI gui_sigout 選擇信號GUI /power caculate(功率譜分析) directpower 直接譜分析 indirectpower 間接譜分析(估計譜分析) NOISE 噪聲譜分析 /sigout(常見信號產生) sigout 離散信號產生
標簽： freqcirconv timecirconv freqconv dupconv
上傳時間： 2016-08-26
上傳用戶：13188549192
he algorithm is equivalent to Infomax by Bell and Sejnowski 1995 [1] using a maximum likelihood formulation. No NOISE is assumed and the number of observations must equal the number of sources. The BFGS method [2] is used for optimization. The number of independent components are calculated using Bayes Information Criterion [3] (BIC), with PCA for dimension reduction.
標簽： equivalent likelihood algorithm Sejnowski
上傳時間： 2016-09-17
上傳用戶：Altman
This function calculates Akaike s final prediction error ％ estimate of the average generalization error. ％ ％ [FPE,deff,varest,H] = fpe(NetDef,W1,W2,PHI,Y,trparms) produces the ％ final prediction error estimate (fpe), the effective number of ％ weights in the network if the network has been trained with ％ weight decay, an estimate of the NOISE variance, and the Gauss-Newton ％ Hessian. ％
標簽： generalization calculates prediction function
上傳時間： 2014-12-03
上傳用戶：maizezhen
This function calculates Akaike s final prediction error ％ estimate of the average generalization error for network ％ models generated by NNARX, NNOE, NNARMAX1+2, or their recursive ％ counterparts. ％ ％ [FPE,deff,varest,H] = nnfpe(method,NetDef,W1,W2,U,Y,NN,trparms,skip,Chat) ％ produces the final prediction error estimate (fpe), the effective number ％ of weights in the network if it has been trained with weight decay, ％ an estimate of the NOISE variance, and the Gauss-Newton Hessian. ％
標簽： generalization calculates prediction function
上傳時間： 2016-12-27
上傳用戶：腳趾頭
The exercise should be finished in English. 2. According to Prof. Zhang s requirement, this exercise mainly focuses on the BER performance of some wireless communication system using specific coding and modulation type through the AWGN channel. Signal-to-NOISE ration (SNR) varies from 5dB to 20dB.
標簽： requirement According exercise finished
上傳時間： 2014-01-06
上傳用戶：zhangyigenius
RLS算法，編寫了MATLAB程序實現自適應干擾對消。給出信號實例，用于驗證所編寫程序的性能。所給信號為：①噪聲與語音的混合信號——signalnosie.wav；②噪聲信號——NOISE.wav。兩信號均為立體聲，PCM壓縮，采樣速率為48000Hz，采樣精度16bits。
上傳時間： 2014-12-05
上傳用戶：anng
The software is capable to simulate space time code [1] for QPSK modulation using different number of state. Examples of generator matrix up to 256 stetes are provided. Variable signal to NOISE ratio (SNR) might be applied to produce bit error rate (BER) or frame error rate (FER) curves.
標簽： modulation different software simulate
上傳時間： 2014-01-22
上傳用戶：qq1604324866
A MATLAB GUI platform for realizing the radiation pattern of narrowband beamformer with random array geometry. User can specify the array geometry, directions of incoming signals, NOISE power, and the type of beamformer. Useful for gaining insight about collaborative beamforming in sensor networks and random arrays. You need both randomarray.fig and randomarray.m to work.
標簽： beamformer narrowband realizing radiation
上傳時間： 2014-01-06
上傳用戶：qb1993225
