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This paper presents the performance evaluation of full-standard wireless signals overlay on two access networks: (i) legacy long-reach networks and (ii) next-generation networks using orthogonal frequency division multiplexing (OFDM) modulation. The proposed bundle of full-standard OFDM wireless signals includes broadcast of ETSI EN 300 744 DVB-T signals and multi-format wireless signals 3GPP long-term...
Increasing the spectral efficiency was always the motivation behind the evolution of wireless communication systems. Also, due to the widespread usage of wireless systems, securing the transmitted data rises as a main concern nowadays. Hereby, we introduce a scheme that increases the capacity of wireless systems by transmitting multiple independent data streams, while using the space domain as a source...
This document reviews the main design decisions that have been made for the physical layer design of the Device-to-Device (D2D) synchronization signals and channels as part of the 3GPP Release-12 specification work. The intention is to provide some context and background to the agreed design decisions because this rationale will not be described in the 3GPP specifications.
Reliable and accurate localization of users is critical for many applications in wireless networks. In range-based localization, the position of a node (agent) can be estimated using distance measurements to nodes with known positions (anchors). Optimal power allocation of the anchors reduces positioning error and improves network lifetime and throughput. We formulate and solve a robust power allocation...
In this paper, we propose a full-duplex physical-layer network coding (FD-PLNC) scheme for reciprocal asymmetric frequency-selective multipath channels using orthogonal frequency-division multiplexing (OFDM) and denoise and forward (DNF) relaying. We consider a network scenario of two-way relay channels (FD-TWRCS) with two source nodes, A and B, intending to exchange information with the aid of a...
Pilot contamination is known to be one of the main impairments for massive MIMO multi-cell communications. Inspired by the concept of fractional frequency reuse and by recent contributions on pilot reutilization among non-adjacent cells, we propose a new pilot allocation scheme to mitigate this effect. The key idea is to allow users in neighboring cells that are closest to their base stations to reuse...
Filter Bank Multi-Carrier (FBMC) with Offset Quadrature Amplitude Modulation (OQAM) has been actively investigated for decades. Now it is also a candidate for 5G air interface waveform. Nevertheless, when it goes to standardization consideration, people still prefer Orthogonal Frequency Division Multiplex (OFDM), in spite of its identified drawbacks for 5G. Such conservative attitude comes from the...
Carrier aggregation (CA) is a technique introduced in LTE-Advanced to achieve a higher throughput by increasing bandwidth. In this work, the spectrally efficient frequency division multiplexing (SEFDM) bandwidth compression technique is utilized to enhance CA performance. This work reports experimental demonstration of SEFDM and shows that up to 7 component carriers (CCs) can be aggregated in a given...
5G wireless systems are envisioned to provide ultra-high data rates, increased robustness and low latency for new applications such as machine-to-machine (M2M) and car-to-car (C2C) communications. This paper considers high-speed visible light communication (VLC) as a candidate serving technology to fulfill this set of requirements. Synchronization as the first step towards reliable data detection...
In this paper, the PWM encoding of an optical OFDM transmission is studied and simulated. Traditional optical OFDM schemes make use of linear drivers, but the inherent nonlinear behavior of the optical emitters produce a harmful effect on the demodulated signal. PWM allows the use of nonlinear drivers, avoiding this harmful effects and increasing the efficiency of the transmission. Furthermore, synchronization...
This paper investigates experimentally the performance of optical spatial modulation (OSM) with orthogonal frequency division multiplexing (OFDM) in a multiple-input and multiple-output (MIMO) based visible light communication (VLC) system. Gallium nitride based micro light emitting diodes (µLEDs) are considered as a transmitter unit. A two transmitter and two optical receiver based MIMO setup is...
This paper reports a demonstration of high speed visible light communications using a blue laser diode combined with a remote phosphor. This method both generates white light and supports multi Gb/s communications. Data rates of up to 5.62 Gb/s and 6.52 Gb/s were achieved by using OFDM with fixed-rate and adaptive loading approaches, respectively. A total data rate of 10 Gb/s was found to be achievable...
The problem of bit and power loading for bit rate maximization in OFDM data communications over indoor powerline channels is investigated and a simple method for bit/power allocation in a single cycle of the mains is developed. The proposed solution is based on the so called Zadeh's representation for modelling the linear periodically time-varying behavior of powerline channels. Numerical results...
A wireless relay node employing Wireless Physical Layer Network Coding (WPLNC) must use a specific mapping in order to combine incoming signals. This mapping, however, cannot be selected arbitrarily. Together with the signals from the other network relays, it has to allow the destinations to be able to recover the source data from the available observations. Moreover the mapping should optimize a...
The combined bulk/per-tone transmit antenna selection strategy has been shown to achieve optimal diversity and coding gains for single-hop systems with multiple transmit and receive antennas. In this paper, we extend this strategy to the case in which a set of user pairs communicate via a cluster of intermediary amplify-and-forward relaying nodes. We obtain an upper bound on the outage probability...
This paper investigates the applicability of generalized frequency division multiplexing (GFDM) for an uplink scenario where several users are not perfectly synchronized, as it appears in wireless sensor networks (WSN). We compare the performance in terms of inter-user interference (IUI) caused by time and frequency misalignments between users, where the physical layer is realized with GFDM and OFDM...
With the exponential growth of wireless data traffic and the increasing scarcity of licensed spectrum, mobile network operators intend to use the unlicensed spectrum, such as the Industrial, Scientific and Medical (ISM) bands and TV white space, to offload their traffic. In the future, it is very likely that two of the most prominent wireless technologies, Long Term Evolution (LTE) and WiFi, will...
In this paper, a novel narrowband interference (NBI) cancellation scheme based on structured compressive sensing (SCS) for dependable vehicular communications systems is proposed. The temporal joint correlation of the repeated training sequences in the preamble are exploited by SCS-based differential measuring (SCS-DM) to acquire the joint measurements matrix of the NBI. Using the proposed structured...
For fast-moving vehicles, radio channels can be severely fast-fading. Under such circumstances, the performance of multi-carrier communication systems, such as OFDM-based ones, are often limited by the inter-carrier interference (ICI) caused by time variation of the channel within one transmit symbol. The conventional way to mitigate the effect of ICI is to increase the frequency spacing between neighboring...
Autonomous underwater vehicles (AUVs) are deployed in search and rescue operations where it is difficult for divers to reach. During the operation a fleet of AUVs communicate among themselves and exchange two type of information. The first includes control signal which has a low-data rate but has a very stringent bit error rate (BER) requirement and the second being the data collected by the AUVs...
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