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This work presents a study on the performance of a hybrid 5G RF/FSO communication system. Both transmitter and receiver communicate through two paths: the first link operates under Radio-Frequency (RF) technology, assumed to undergo a Weibull fading channel, while the second link operates under Free Space Optical (FSO) technology, subject to Málaga-M turbulence model with the presence of pointing...
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...
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...
In cognitive radio networks, secondary users (SUs) must accurately sense the spectrum of primary user (PU) to acquire their own communication opportunities without interfering PU's communication. Collaborative spectrum sensing (CSS) among SUs can improve the probability to detect PU's communication, compared to non-collaborative spectrum sensing, where each SU senses signal independently. In this...
Some of the future wireless networks are related to the provision of higher data rates and lower energy consumption. In contrast to the clear increasing spectrum demand, bandwidth is a limited resource. Cooperative diversity allows to increase the spectral efficiency and the reliability of the communication. However, in scenarios with high node density and high mobile data traffic volume the collaboration...
In this paper, we study the performance of a dualhop amplify-and-forward (AF) communication system over asymmetric links composed of Radio-Frequency (RF) and Free-Space-Optical (FSO) links in the presence of atmospheric turbulence as well as pointing error impairments under both heterodyne detection and intensity modulation with direct detection (IM/DD) techniques. The RF link is assumed to operate...
Direct Device-to-Device (D2D) communication permits to offload the network, increase the capacity, and extend the cellular coverage. In D2D systems, user equipments (UEs) do not necessarily communicate via evolved Node Base station (eNB); instead, they are allowed to communicate directly with each other. This underlying communication generates interference due to reusing the same resources of the...
Recently, Single-Cell Point-to-Multipoint (SC-PTM) has been studied in 3GPP as an agile broadcast/multicast mechanism. Due to cell-level support of the multicast service, SC-PTM can adjust the service area dynamically and its scheduling is quite agile. In the conventional SC-PTM, however, a single multicast transmission is set for the worst user and provided for all the users regardless of their channel...
In this paper, we investigate the performance of a generic relay system for small cells. The main features include the selection decode-and-forward (DF) scheme, Rician and Rayleigh fading, single or repeated transmissions in direct link, and maximal-ratio combining at destination. We are able to derive a set of closed-form expressions for the end-to-end performance. Based on these formulas, we define...
In cellular mobile wireless networks, nonlinear channel fading is always a critical factor which will scientifically deteriorate the Quality of Service (QoS) for the users. However, it is difficult to describe the nonlinear channel fading by precise mathematical model because of its complexity. So, the control of wireless networks becomes an especial tough work. In this paper, a power and rate control...
Considering unreliable wireless backhaul connections across transmitters, we investigate the outage performance of a finite-sized selective relaying system with M transmitters and N relays under Nakagami-m fading channels. To send the source message to the destination, the transmitter-relay pair providing the highest end-to-end signal-to-noise ratio is selected for transmission. The backhaul reliability...
The existence of high multipath resolution allows Rake collectors to maximize the signal-to-noise ratio efficiently. However, previous studies show that the conventional Rake receivers do not consider the multipath effect caused by long channel response such as in ultra-wideband wireless system. In this paper, we propose a new statistical selection (SS)-Rake receiver in long multipath channel. The...
Citizen Broadband Radio Service band (3550–3700 GHz) is seen as one of the key frequency bands to enable improvements in the performance of wireless broadband and cellular systems. A careful study of interference caused by a secondary cellular communication system coexisting with an incumbent naval radar is required to establish a pragmatic protection distance, which not only protects the incumbent...
The evaluation of an IoMT system needs to include the assessment of LPI, LPE, or LPD. To provide a building block for these metrics, in this paper, we introduce the notion of the information-theoretic secrecy. In particular, we focus on the shadowing fading with the log-normal distribution. We extend a recent analysis for uncorrelated eavesdroppers to the case of correlated ones. Then we derive the...
In this paper, we investigate the information-theoretic secrecy of a system with multiple legitimate receivers and multiple eavesdroppers. This system is subject to the Nakagami-m fading. Unlike some existing works, we do not assume that the fading parameters are identical or integers. Although the complexity is significantly increased, we are able to derive a set of closed-form formulas for the outage...
Cloud-fog radio access is a promising technology in evolving wireless communication systems, but its success depends on security. It is fundamental to conduct the secrecy analysis in the physical layer due to the special architecture of CF-RAN. In this paper, we investigate the secrecy impacted by general path-loss effects. We show that the mathematical kernel is the Weibull distribution function...
One of the most important factors affecting the quality of service (QoS) in orthogonal frequency division multiple access (OFDMA) networks is the intercell interference (ICI). An efficient technique for mitigating ICI is the well-known fractional frequency reuse (FFR), wherein cells are partitioned into center and edge spatial regions and different frequency reuse factors are applied to both of them...
In this paper, we analyze the outage probability of multiple-input multiple-output cognitive cooperative radio networks (CCRNs) with multiple opportunistic amplify-and-forward relays. The CCRN applies underlay spectrum access accounting for the interference power constraint of a primary network and utilizes orthogonal space-time block coding to transmit multiple data streams across a number of antennas...
The Internet of Things (IoT), describing the Machine Type Communications (MTC), is in the center of many new technical studies and industrial projects. It is also a central topic for the future 5G technologies standardization. Pending the new generation of cellular networks, the 3rd Generation Partnership Project (3GPP) has already standardized in May 2016, an evolution of the 2G and 4G networks to...
In this paper Discrete Cosine Transform and Fast Fourier Transform based Orthogonal Frequency Division Multiplexing (DCT-OFDM and FFT-OFDM) systems with frequency modulation are examined. Frequency modulation is used in both systems to achieve constant envelope (CE) signals and hence 0 dB PAPR; well-suited for efficient power amplification. The performances of such systems are examined over flat fading...
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