Technology is all around us and it’s changing rapidly, expanding Internet access has had huge impacts on everyday lives as people do everything on their phones and computers. The widespread growth in the use of digital computers, have an increasing need to be able to communicate with machines in a simpler manner. One of the main tasks that can simplify communication with machines is speech recognition. In this work, we introduce the Arabic speech commands database that contains six Arabic control order words and Arabic spoken digits. The created database is used to analyze and compare the recognition accuracy and performance of three recognition techniques which are, Wavelet Time Scattering feature extraction with Support Vector Machine (SVM) classifier, Wavelet Time Scattering feature extraction with Long Short-Term Memory (LSTM) classifier, and Mel-Frequency Cepstrum Coefficients (MFCC) feature extraction with K-Nearest Neighbor (KNN) classifier. Finally, the experimental results show that the most accurate prediction of the database commands was 98.1250% given by Wavelet Time Scattering feature extraction and LSTM classifier and the fastest training time for the database was 144 minutes given by MFCC and KNN classifier. arabic 5 English 42
Osama A. Alkishriwo, Lina Tarek Benamer(12-2020)

In this paper, imposing the Hadamard Transform (HDT) on Orthogonal Space-Time Block Codes (OSTBC) schemes using multiple transmit antennas is proposed in order to increase the reliability and improve the error performance of wireless communications. It is referred to as joint Hadamard transform and OSTBC schemes with multiple transmit antennas. However, HDT is used to change the location of constellation points by converting the transmit symbols of OSTBC system, and hence extending the Euclidean distance between transmit symbols for a precise detection. Simulation results demonstrated that increasing the number of transmit antennas in OSTBC systems employing 8-PSK improves the Bit Error Rate (BER) performance as in the case of OSTBC 2×2 scheme where an SNR of about 13.5 dB is required to achieve a BER of 〖10〗^(-6), while only about 7 dB in OSTBC 8×8 scheme is required to obtain the same error probability. It is also demonstrated that imposing the Hadamard criteria on the OSTBC 2×2, 4×4, and 8×8 schemes has showed a performance improvement of about 3 dB, 6 dB and 9 dB, respectively, as compared to the conventional OSTBC systems.
Taissir Y. Elganimi, Marwan B. Elkhoja(4-2019)

Multiple Input Multiple Output (MIMO) systems with limited Radio Frequency (RF) chains play a pivotal role in the Fifth Generation (5G) of wireless networks. However, the transmitter of Generalized Spatial Modulation MIMO (GSM-MIMO) systems that characterized by a single RF chain and multiple active antennas is capable of reducing both the energy consumption and the transmitter cost. In this paper, combining GSM-MIMO systems with the fully digital Geometric Mean Decomposition (GMD)-based precoding scheme and Analog Beamforming (ABF) into Hybrid Beamforming (HBF) regime is presented for Millimeter-wave (mmWave) massive MIMO systems which is a key enabler for 5G networks. In addition, applying the norm-based user selection algorithm in GSM-MIMO scheme with GMD-based hybrid precoding is proposed, and referred to as Multiuser Steered GSM-MIMO (MUS-GSM-MIMO) scheme. Simulation results demonstrate that the proposed schemes are capable of achieving considerable performance gains over the conventional GSM-MIMO schemes, while avoiding the overwhelming costs of multiple RF chains. Therefore, the proposed schemes are very efficient and highly suitable for large-scale and 5G wireless networks.
Taissir Y. Elganimi, Amani A. Aturki(9-2020)