scholarly journals Architecture for Collision-Free Communication Using Relaxation Technique

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Saeed ur Rehman ◽  
Rizwan Akhtar ◽  
Zuhaib Ashfaq Khan ◽  
Changda Wang

In today’s world we are surrounded by world of smart handheld devices like smart phones, tablets, netbooks, and others. These devices are based on advance technologies of multiple-input and multiple-output, Orthogonal Frequency Division Multiplexing (OFDM), and advance data reliability techniques such as forward error corrections. High data rates are among the requirements of these technologies for which turbo and low density parity check codes (LDPC) are widely used in these standards. In order to get high speed, we need multiple and parallel processors for the implementation of such codes. But there exists a collision problem as a consequence of parallel processor. This problem results in increase latency and increase of hardware complexity. In this work an approach for collision problem is presented in which network relaxation technique is used which is based on a fast clique detection. The proposed approach results in high throughput in terms of latency and complexity. Furthermore, the proposed solution is able to solve the collision problem by connecting network optimization for achieving high throughput.

Author(s):  
Prof. Madhuri Zambre

In recent days, power line communication is one of the emerging technologies for high data rates (data transmitted at high speed). It is also cost effective and dependable channel. It is used in many applications such as home automation, broadband internet access, car embedded systems etc. Orthogonal Frequency Division Multiplexing dependent PLC physical layer is presented in this work. It is measured in terms of BER employing MATLAB 2013a. Here, multipath channel model is employed for the purpose of simulation because of the unavailability of a primary PLC channel.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Saad M. Hardan ◽  
Ayad A. Abdulkafi ◽  
Saadi Hamad Thalij ◽  
Sherine S. Jumaah

Abstract The continued increase in several mobile applications forces to replace existing limited spectrum indoor radio frequency wireless connections with high-speed ones. Visible light communications (VLC) technology has gained prominence in the development of high data rate transmission for fifth-generation networks. In optical wireless communications, light-emitting diode (LED) transmitters are used in applications that desire mobility as LED divergence enables larger coverage. Since each VLC access point covers a small area, handovers of mobile users are inevitable. Wavelength division multiplexing (WDM) can be used in VLC systems to tackle the above issue and to meet the increasing demand for indoor connectivity with high bit rates. In this paper, a new system architecture for WDM with coded modulated optical in orthogonal frequency division multiplexing (OFDM) VLC system in conjunction with red, green, blue, and yellow (RGBY) LEDs is proposed to reduce the impact of random receiver orientation of indoor mobile users over VLC downlink channels and improves the system’s bit-error-rate (BER) performance. Simulation results show that the proposed method is not affected by the user’s mobility and hence it performs better than other approaches, in terms of BER for all scenarios and at all positions. This study reveals that using WDM-OFDM-VLC with RGBY LEDs to construct a VLC system is very promising.


2019 ◽  
Vol 16 (2) ◽  
pp. 430-435
Author(s):  
N. Girinath

As the world moves toward 3G/4G there is a need for high data rate and relatively wide bandwidths. OFDM (Orthogonal Frequency Division Multiplexing) a form of multicarrier modulation technique is widely used to achieve high speed efficient data transmission at the rate of several Mbps. It is used in Wi-Fi standards like 802.11a, 802.11n, 802.11ac, broadcast standards like Digital Video Broadcast (DVB) and cellular telecommunications standard LTE. The main advantage of OFDM compared to single carrier modulation is their robustness to channel fading in wireless environment, high baud rates and less inter symbol interference. One major disadvantage is its High PAPR. PTS partial transmit sequences (PTS) and selective mapping are proposed to reduce it. Since FFT is core block of OFDM it must be able to adapt itself to ever changing digital world. A function specific reconfigurable 2k SDF (Single path delay feedback) FFT is proposed. It utilizes less power and can be configured for different FFT sizes ranging from 16-point to 1024-point. The validity and efficiency of the architecture have been verified by simulation in hardware description language VERILOG and targeted on Virtex-6 device. Finally PAPR is estimated by MATLAB simulation.


2014 ◽  
Vol 513-517 ◽  
pp. 3987-3991
Author(s):  
Naveed Ur Rehman ◽  
Lei Zhang ◽  
Muhammad Zahid Hammad ◽  
Emmanuel Anania Mwangosi

The rapid growth within the field of digital communication during the recent years expanded the need for high-speed data transmission to support a wide range of services such as: video, data and voice in wireless communication systems, etc. Orthogonal frequency division multiplexing (OFDM) and a multicarrier modulation scheme are employed to achieve the high data rates. Since OFDM is very much sensitive to carrier frequency offsets, which cause the Inter-carrier Interference (ICI) leads to mitigation of this ICI is necessary. The objectives of this paper are to, proposed an efficient ICI self-cancellation scheme to mitigate the effect of ICI on OFDM systems. For this purpose, a redundant data is transmitted onto adjacent sub-carriers such that the ICI between adjacent sub-carriers cancels out at the receiver side. One data symbol is modulated into a group of adjacent sub carriers with a group of weighting coefficients. At the receiver side, the received signals are linearly combined on these sub carriers with proposed coefficients. The residual ICI contained in the received signals can then be further reduced. This study provides significant carrier-to-interference power ratio (CIR) improvement, which has been studied theoretically and supported by simulations. Since no channel equalization is required to reduce ICI, so the proposed scheme doesnt increase the system complexity.


Frequenz ◽  
2017 ◽  
Vol 71 (9-10) ◽  
pp. 427-438
Author(s):  
Steffen Büchner ◽  
Lukasz Lopacinski ◽  
Rolf Kraemer ◽  
Jörg Nolte

Abstract 100 Gbit/s wireless communication protocol processing stresses all parts of a communication system until the outermost. The efficient use of upcoming 100 Gbit/s and beyond transmission technology requires the rethinking of the way protocols are processed by the communication endpoints. This paper summarizes the achievements of the project End2End100. We will present a comprehensive soft real-time stream processing approach that allows the protocol designer to develop, analyze, and plan scalable protocols for ultra high data rates of 100 Gbit/s and beyond. Furthermore, we will present an ultra-low power, adaptable, and massively parallelized FEC (Forward Error Correction) scheme that detects and corrects bit errors at line rate with an energy consumption between 1 pJ/bit and 13 pJ/bit. The evaluation results discussed in this publication show that our comprehensive approach allows end-to-end communication with a very low protocol processing overhead.


Author(s):  
Yazan Alkhlefat ◽  
Sevia Mahdaliza Idrus Sutan Nameh ◽  
Farabi M. Iqbal

Current and future wireless communication systems are designed to achieve the user’s demands such as high data rate and high speed with low latency and simultaneously to save bandwidth and spectrum. In 5G and 6G networks, a high speed of transmitting and switching is required for internet of things (IoT) applications with higher capacity. To achieve these requirements a semiconductor optical amplifier (SOA) is considered as a wavelength converter to transmit a signal with an orthogonal frequency division multiplexing with subcarrier power modulation (OFDM-SPM). It exploits the subcarrier’s power in conventional OFDM block in order to send additional bits beside the normally transmitted bits. In this paper, we optimized the SOA’s parameters to have efficient wavelength conversion process. These parameters are included the injection current (IC) of SOA, power of pump and probe signals. A 7 Gbps OFDM-SPM signal with a millimeter waves (MMW) carrier of 80 GHz is considered for signal switching. The simulation results investigated and analyzed the performance of the designed system in terms of error vector magnitude (EVM), bit error rate (BER) and optical signal-to-noise ratio (OSNR). The optimum value of IC is 0.6 A while probe power is 9.45 and 8.9 dBm for pump power. The simulation is executed by virtual photonic integrated (VPI) software.


2016 ◽  
Vol 2016 (1) ◽  
pp. 000155-000159 ◽  
Author(s):  
Muhammad Waqas Chaudhary ◽  
Andy Heinig

Abstract High speed communication has been a topic of great interest in the last decade due to excessively high data rates required between chips especially pushed by the measurement equipment industry to support extremely high bandwidth data sampling. Serial communication is chosen to support these data rates which are pushing further and further into higher data rate regimes. It is important to understand how the 2.5D integration of chips on the interposer can support serial communication and what the designer can do to leverage the special features of interposer channel to achieve lower power and higher speed. This paper will present the interposer complete channel full 3D Electromagnetic simulation based model extraction. It also presents the simulation of channel with real serial communication transmitter and receiver circuit models to describe the proposed interposer performance for multi Gb/s data rates. Also a comparison is shown for different settings of transmitter and receiver circuits under the interposer channel.


2019 ◽  
Vol 0 (0) ◽  
Author(s):  
Nikhlesh Kumar Mishra ◽  
Kamal Kishore Upadhyay ◽  
N. K. Shukla

AbstractFor addressing needs of modern day communication needs, new type of networks are required to be evolved to cater the demand of high data rates. Use of survivable elastic-optical-network (EON) with existing passive-optical-networks (PON) may provide the solution for this. The present work focus on employing EON–PON based wave-length-division multiplexing enabled communication system comprises of 2×5 Gbps for downlink and 2×1 Gbps for uplink over a single-mode-fibre of length 100 km. The results are the evaluated via bit-error-rate analyser, q factor and eye diagrams.


2021 ◽  
Vol 11 (19) ◽  
pp. 8895
Author(s):  
Balamurali Ramakrishnan ◽  
Arun Kumar ◽  
Sumit Chakravarty ◽  
Mehedi Masud ◽  
Mohammed Baz

Nowadays, many prevalent frameworks for medical care have been projected, studied, and implemented. The load and challenges of traditional hospitals are increasing daily, leading to inefficient service in the health system. Smart hospitals based on advanced techniques play a crucial part in advancing the health services of rural people. It spares the time and money involved in travel, and patient medical reports can be shared instantly with the experts regardless of geographical constraints. Currently, the role of technology in hospitals is limited due to various restrictions, such as the obtainability of a high spectrum, low latency, and high-speed network. In this paper, we focused on the implementation of an advanced waveform with high spectral performance. Filer Bank Multi-Carrier (FBMC) is considered a strong contender for the upcoming 5G-centered smart hospitals due to its high data rate, no leakage of the spectrum, and less sensitivity to frequency error. In addition, a comparison of the spectral utilization of orthogonal frequency division multiplexing (OFDM) and FBMC in terms of bit error rate (BER), peak power (PP), power spectral density (PSD), noise-PSD, capacity and magnitude, and phase response is illustrated. Numerical results show that the FBMC achieved a throughput gain of 1 dB and its spectral performance is better than the OFDM; hence, it is a better choice for the proposed application compared to the current standard OFDM.


2013 ◽  
Vol 8 (1) ◽  
pp. 734-742 ◽  
Author(s):  
Er. Rajeev Thakur ◽  
Er. Sukhbir Singh ◽  
Er. Abhishek Sharma

Present era demands high bandwidth with high data rates especially for internet. For high data rates requires high speed transmission medium like optical fiber. To overcome the bottle neck of last mile communication free space optics has emerged as a better option for radio engineers. Using Infrared beams provides license free spectrum, high bandwidth with maximum data rates. In this paper different aspects for utilizing an FSO link are reviewed showing there advantages and disadvantages. 


Sign in / Sign up

Export Citation Format

Share Document