Sinan M. Abdul Satar

Bio: Sinan M. Abdul Satar is an academic researcher from University of Technology, Iraq. The author has contributed to research in topics: Orthogonal frequency-division multiplexing & Bit error rate. The author has an hindex of 2, co-authored 13 publications receiving 11 citations.

Performance study of ACO-OFDM and DCO OFDM in optical camera communication system

Abstract: In this paper, two forms of optical OFDM (orthogonal frequency division multiplexing) have been investigated that are suitable for optical camera communication systems. The distinction is rendered by evaluating bit error rate versus signal to noise ratio of optical camera communication systems but, it is power effective for higher SNR values. This was because the DC bias used in DCO-OFDM is unreliable as for the optical capacity, whereas utilizing just half the subcarriers to transport data in ACO-OFDM in terms of bandwidth is unsuccessful. In addition to that, this research will be focused on optical camera communication system and implementation in the case of use for optical OFDM, which produces the clipping noise. However, they will gain SNR overall if we choose a good clipping factor. We found that ACO OFDM is better because of lower bit loading. This research explores the difference between the 2D ACO-OFDM and the 2D DCO-OFDM from the perspective of implementation. This enables us to test all the performance without any required hardware configuration. In this paper, the BER versus SNR ratio analysis for two optical wireless communication systems has been studied for different clipping factors: 0.8, 1, and 2. The BER performance of the two forms of optical OFDM. The single-carrier modulation solution is often contrasted to show the robust efficiency of the proposed method. This system has been implemented using Lab-view 2019 software.

An ICI Reduction Based on PAPR Clipping in Coherent Optical OFDM System

Abstract: The Inter-Carrier Interference (ICI) compensation for Coherent Optical Orthogonal Frequency Division Multiplexing (CO-OFDM) system has been studied in this paper. The purpose behind is to investigate the presence of ICI due to the impact of Laser Phase Noise (LPN) and Fiber Non-Linearity (FNL). Thereby, we propose a simple clipping scheme which represents an effective distortion algorithm to decrease the Peak to Average Power Ratio (PAPR) for 4QAM system. The method exhibits a significant process on ICI cancellation in CO-OFDM system. The OFDM signal is basically transmitted along 550km distance rated at 10Gbps single mode fiber for the coherent optical mode. The new findings show that the receiver sensitivity is highly improved below 10−3 FEC for laser power 5dBm; and archives about 1dBm to 2.4dBm when laser power becomes 8dBm at a typical clipping ratio of 0.6. In particular, the system exhibits a good performance over a 385km transmission distance in comparison to the conventional CO-OFDM. As a result, the proposed clipping shows that the system can enhance its the performance by reducing ICI in the CO-OFDM system; in addition to present a high robustness in BER metric against FNL by a clear reduction in PAPR.

Performance Enhancement of Speech Scrambling Techniques Based on Many Chaotic Signals

Abstract: scrambling method structure consists of three main components: scrambling, noisy channel and descrambling. The scrambling and descrambling processes. On the basis of chaotic signals, a speech scrambling technique is an essential work to upgrade and improve data protection in secure communication applications, especially military applications, and the main idea is immunity against eavesdropper to achieve security. The aim of uses the key encrypted in the Quadrature Amplitude Modulation-Orthogonal Frequency Division Multiplexing QAM OFDM system to improve performance of the Bits Error Rates BER on the receiving side that is robust against the effects of the Additive White Gaussian Noise AWGN. This paper has been published a speech authentication model using five separate chaotic maps / flows: Logistic maps LM, Baker maps BM, Henon map HM, Rossler system ROS and Lorenz system LS based on 16-64 QAM_OFDM technique. The evaluation measures included six different tests: Segmental spectral signal to ratio of noise SSSNR, Log spectral distance d LOG , Linear predict coding distance d LPC , cepstral distance d CD , Frequency Weighted log Spectral distance dFWLOG and Bit error rate BER. Objective tests to measure the residual intelligibility R.I. of speech between the original and scrambling/ descrambling signal for proposed models: d LOG = 14.5415, d LPC = 0.9741, d CD = 8.8503, SSSNR= −26.506, and dFWLOG= 20.9976, While the BER between the original signal and recovered signal at 10 dB about 10-03, Which is big enough to protect the brute force attack encryption signal. We conducted a series of unpredictable map / flow randomness tests: Lyapunov exponent test and Auto correlation.

Performance Improvement Of OOFDM Systems Based On Advanced Logarithmic Companding Technique

Abstract: High peak-to-average power ratio (PAPR) is a common problem in Orthogonal Frequency Division Multiplexing (OFDM) transmissions. In this paper, an advanced logarithmic companding technique is interested to reduce this factor due to their flexibility and low complexity. We evaluate the performance of the proposed advanced logarithmic technique comparing with typical logarithmic and un-companded schemes via simulations in Intensity Modulation/Direct Detection Optical Orthogonal Frequency Division Multiplexing (IM/DD OOFDM) system. The proposed advanced logarithmic Companding technique guarantees the improved performance in terms of Bit Error Rate (BER) and Quality Factor (QF) while reducing PAPR effectively and efficiently by modifying the amplitude of the transmitted signals. Our results confirm that the suggested scheme exhibits a good ability to reduce PAPR and a good BER performance based on the use the both of (k and y) factors to be chosen in relation to acceptable or desired PAPR, BER, and QF requirements. At the complementary cumulative distribution function (CCDF) of 10 -3 , the PAPR value of our proposed scheme is about 6.4 dB lower than those of un-companded signal at best control factor used of y=0.1, accordingly the QF is 11.8 dBm and the BER is 4.9×10 -5 .

OFDM for Optical Communications

Abstract: Orthogonal frequency division multiplexing (OFDM) is a modulation technique which is now used in most new and emerging broadband wired and wireless communication systems because it is an effective solution to intersymbol interference caused by a dispersive channel. Very recently a number of researchers have shown that OFDM is also a promising technology for optical communications. This paper gives a tutorial overview of OFDM highlighting the aspects that are likely to be important in optical applications. To achieve good performance in optical systems OFDM must be adapted in various ways. The constraints imposed by single mode optical fiber, multimode optical fiber and optical wireless are discussed and the new forms of optical OFDM which have been developed are outlined. The main drawbacks of OFDM are its high peak to average power ratio and its sensitivity to phase noise and frequency offset. The impairments that these cause are described and their implications for optical systems discussed.

Performance enhancement for visible light communication based ADO-OFDM

Abstract: The increasing demand for bandwidth through modern applications and multimedia services has led to high-speed wireless communications Optical wireless communications (OWC) encourages solutions that provide a higher data rate due to the large bandwidth available In this paper, performance enhancement approaches are studied and simulated for visible light communication (VLC) as a case study The orthogonal frequency division multiplexing (OFDM) systems are used to investigate Intensity modulation/direct detection (IM/DD) to improve the performance of VLC The IM/DD in OWC requires positive real OFDM symbols, so there are many approaches to satisfy this requirement This paper proposes a model of Asymmetrically Clipped DC-Biased Optical (ADO-OFDM) to use in OWC/VLC environment The proposed system has avoided the use of the noise cancellation technology that is used in traditional ADO-OFDM The results show that the ADO-OFDM has the best spectral efficiency than DC-biased optical (DCO-OFDM) and Asymmetrically clipped optical (ACO-OFDM) Also, it has better optical efficiency than DCO-OFDM with the equally overall bit error rate (BER) at the same signal-to-noise ratio Hamming channel coding/decoding with different code lengths is applied in various optical OFDM schemes for BER improvements Furthermore, we simulate and analyze these optical OFDM systems with many modulation orders