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This paper studies the impact of various parameters used for modeling indoor VLC channels, considering a mobile user within the confined environment. The main investigated parameters are either physical or geometrical. First, we classically study the impact of optical properties of surface materials. Then, the effect due to the presence of the user body inducing various VLC receiver orientations is...
Currently the world is experiencing a fast evolution of modern communication and information technologies due to infrastructure development. Consequently, there is a growing need to be able to quickly and resource-efficiently receive, transmit and process information, monitor different physical processes, environment. For this purpose, optical communication systems and optical fiber sensors are directly...
Radio-over-fiber is a key-enabling-technology for next generation wireless networks. To support an increasing number of antennas, a CloudRAN approach that maximally aggregates base station functionality of the different antenna sites is the most economically feasible. To support light weight antenna units, analog radio-over-fiber is most promising. To mitigate linearity constraints of optical modulators,...
In this research, authors propose approach to assess lifetime of fiber optic infrastructure (buried cable) based on measurements of chromatic dispersion (CD) and polarization mode dispersion (PMD). The initial dispersion measurements were made right after cable installation then approximately three months (4440 hours) later before start of service, and then repeated measurements in two and a half...
The multiple-input multiple-output (MIMO) concept is of high interest in fiber-optic communication since it is able to overcome the capacity limits of current transmission systems. In this work different receiver-side interference compensation techniques are studied in a spatially multiplexed fiber-optic transmission through 0.5 km multi-mode fiber with a gross bit-rate of 5 Gbps using intensity modulation...
In this paper, the end-to-end error performance of conventional dual-hop system where a source communicates with the destination over an energy harvesting (EH) relay in the lack of a direct link between them, is investigated. In the first phase, relay decodes the signal received from the source, from which it harvests energy according to time switching (TS)-based relaying and power splitting (PS)-based...
Wireless communication has been rapidly developed in recent years acquiring higher demand of efficient wireless systems. Cooperative communication is considered to be capable of effectively meeting this rapid growth where the use of relays improves the throughput and ensures successful transmission to all terminals in a given system. In this paper, a Two-way Decode and Forward Relaying for orthogonal...
The present paper has considered multithreshold decoders for self-orthogonal codes providing a near-optimal efficiency of the error correction under linear computational complexity. New divergence principle used within construction and decoding convolutional codes has been discussed. The paper has shown that usage of such principle allows significantly approximating an area of the decoder effective...
This paper proposes an incremental redundancy hybrid ARQ (IR-HARQ) scheme for the wireless local area network (WLAN) system employing multiband simultaneous transmission. The proposed scheme adopt the rate compatible low-density parity-check (RC-LDPC) codes based on IEEE802.11n LDPC codes and ensure backward compatibility with WLAN devices by using the current WLAN control frame. Additionally, it...
The article represents the most common frequency detection algorithms and shows the results of comparing Goertzel algorithms operation speed and fast Fourier transform on the 1967VN044 processor. The paper substantiates implementation of Fourier speed transform algorithms for the locomotive radio station codegram decoding.
Multi Input Multi Output Constant Envelope Modulation (MIMO-CEM) system is introduced as an alternative candidate for the commonly used MIMO Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system due to its efficient power and complexity capabilities. MIMO-CEM has a transmitter system with an efficient non-linear power amplifier and a receiver system with a 1-bit Analog to Digital Converter...
A novel transceiver antenna selection (TRAS) strategy selecting a pair of antennas for transmission and reception at terminal sources for full-duplex (FD) amplify-forward (AF) multi-input multi-output (MIMO) two way relay networks is offered and analyzed. Antenna pair is selected in accordance with maximum and second maximum signal to selfinterference-plus-noise ratio (SINR) between the sources and...
We study outage performance of a downlink multiple-input multiple-output non-orthogonal multiple access (MIMO-NOMA) in dual hop amplify-and-forward (AF) relay communication system over frequency non-selective and slow fading channels with Nakagami-m distribution. In the network, the base station (BS) and mobile users equipped by multiantenna communicate by the help of fixed gain AF relay with single...
Massive MIMO is a key technology for achieving everincreasing demands in high quality communication and navigation. At the same time multipath transmission in conjunction with transmit/receive signal combining being its corner stone can be incapable to exploit available spatial diversity. Hence it is vital to understand to which extent the parameters of the MIMO system can be optimized in order to...
Zero-forcing receive beamforming (ZFRBF) is integrated with signal space diversity (SSD) under an open-loop scenario with binary phase shift keying (BPSK) modulation. First, a dual-stream transmission scheme under a 2-by-M (M ≥ 2) multiple-input multiple-output scenario is studied. A generalization for any number of simultaneous substreams is then built based on the initial results. We provide an...
An approach to significant widening the bandwidth of the input signals at their digitizing, pulse width modulated compressed transmission and reconstruction is explored. Alias-free digitizing of wide bandwidth input signals is performed by deliberate randomization of signal sampling and innovative Analog-to-Event conversion technique is used for width modulation of the transmitted pulses. Precise...
Filter bank multicarrier (FBMC) has been taken as a candidate modulation for the 5th generation (5G) mobile network, because it exploits well-shaped prototype filters to reduce the inter-symbol-interference (ISI) and inter-carrier-interference (ICI) in OFDM system. To achieve more flexibility in filter performances, this paper designs nearly perfect reconstruction (NPR) filters by relaxing the Nyquist...
The paper presents the development and implementation of a Digital Signal Processing algorithm for the Speed Indication Display with a 24 GHz continuous wave Doppler radar. The algorithm is based on a well-known zerocrossing algorithm and filtering. This paper is focused on implementing this algorithm into a widely used microcontroller, which is usually mounted on the Arduino Uno board. MATLAB/Simulink...
In this article a brief description of a direct conversion receiver is given, sources of affected channels in such a receiver are examined. Practical methods for eliminating of affected channels of a real radio system are proposed.
Cloud radio access network (C-RAN) has been shown to reduce both capital and operating expenditures and provide high spectral efficiency (SE) and energy efficiency (EE). High density of remote radio heads (RRHs) deployments results in inefficient energy consumption. Moreover improvements in the battery capacity of mobile devices lag far behind the surging demand for transmit power, which makes power...
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