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Abd El-Samie, F. E.
- Efficient Compressed Video Communication
Authors
1 Department of Electronics and Electrical Communications, Menoufia University, Menouf 32952, EG
2 University of Liverpool, GB
3 Electronics and Communications Eng., Menoufia University, EG
4 Menoufia University, EG
Source
Networking and Communication Engineering, Vol 6, No 6 (2014), Pagination: 219-226Abstract
This paper presents a chaotic interleaving approach for efficient video transmission with orthogonal frequency division multiplexing (OFDM) with equalization over fading channels. The SPIHT compressed video is converted to luminance and chrominance approach and converted to binary data. The binary data is interleaved with the proposed approach prior to the modulation step. The chaotic Baker map is used in the proposed interleaving approach. In addition to reducing the channel effects on the transmitted data, the proposed chaotic interleaving approach adds a degree of encryption to the transmitted data. The performance of the proposed approach is tested by the transmission of SPIHT compressed video frames over Rayleigh fading channels with chaotic interleaving. Experimental results show that video frames are received with higher peak signal-to-noise ratios (PSNRs) if chaotic interleaving is applied. We also propose an efficient technique to reduce the effects of both multiple access interference (MAI) and intersymbol interference (ISI) in wireless OFDM systems. A hybrid scheme comprising randomization of SPIHT video frames at the transmitter and a regularized equalizer at the receiver unit is suggested and studied. Then, the regularized equalizer is used to reduce the effect of ISI and provide a better estimate of the data. The performance of the proposed scheme is studied and compared with traditional schemes. Our simulation results show a noticeable performance improvement by using the proposed scheme.Keywords
Video Processing, SPIHT Video Compression, OFDM, and Chaotic Map.- Digital Modulation Recognition in OFDM Systems Using Support Vector Machine Classifier
Authors
1 Department of Communication, Menoufia University, IN
2 Department of Communication, Menoufia University, EG
3 Department of Communication, Menoufia University, EG
Source
Networking and Communication Engineering, Vol 5, No 12 (2013), Pagination: 516-525Abstract
Automatic Digital Modulation Recognition (ADMR) is becoming an interesting problem with various civil and military applications. In this paper, an ADMR algorithm in Orthogonal Frequency Division Multiplexing (OFDM) systems using Discrete Transforms (DT) and Mel-Frequency Cepstral Coefficients (MFCCs) is proposed. The proposed algorithm uses various DT techniques as Discrete Wavelet Transform (DWT), Discrete Cosine Transform (DCT) and Discrete Sine Transform (DST) with MFCCs to extract the features of the modulated signal and Support Vector Machine (SVM) to classify the modulation orders. The proposed algorithm avoids over fitting and local optimal problems that appear in artificial neural networks (ANNs). Simulation results show the classifier to be capable of recognizing the modulation scheme with high accuracy (90-100% when using DWT, DCT and DST for some modulation schemes) over a wide Signal-to-Noise Ratio (SNR) range in the presence of Additive White Gaussian Noise (AWGN) and Rayleigh fading channel, particularly at a low signal to noise ratio (SNR).