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This paper analyses the very high system throughput of IEEE 802.11ac by taking into consideration the key features of MAC and PHY layers under a Multiple In Multiple Out (MIMO) channel. Throughput at the MAC layer is calculated from the transmission probability, contention window and transmission stage. Likewise, the new critical attributes of 802.11ac PHY (i.e. modulation and coding schemes, spatial...
As the practical propagation environment suffers from various fading, investigation of a suitable routing protocol for this type of environment is need of the day. Many routing protocols have been evaluated for idle conditions but none of them have taken actual physical environments such as fading, etc. into consideration. In this paper, that particular Issue has been addressed. Three most popularly...
In this paper, we consider a two-hop communication system model, where a source is able to harvest energy and a relay is non-EH half-duplex node over a fading channel. We address the throughput maximization problem for the proposed system model with and without delay tolerant. Two effective algorithms are proposed to solve the joint power allocation and transmission time scheduling problems. The performance...
Radio Resource Management (RRM) plays an important role in wireless communication systems, especially in more advanced systems with more constraint conditions. In this paper, we first proposed a generalized water-filling approach to solve the power allocation problem to minimize sum power while meet the target sum rate constraint with weights. Based on this sum power objective function, we extend...
In this paper, a rate allocation policy is proposed for truncated transmission of spinal codes based on imperfect feedback over block fading channels. By constructing and solving the throughput optimization problem, the optimized rate allocation policy is obtained under the constraint of limited transmission attempts and frame error probability. Both analysis and simulations show that the rate-allocated...
Exploring a cooperative node as a friendly jammer is an effective means of providing secure communication between a source-destination pair in the presence of an eavesdropper. In this work, we consider the use of a wireless-powered friendly jammer. Without relying on external energy supply, the friendly jammer is powered by the source node via wireless power transfer. We apply a simple time-switching...
Multi-beam broadband satellite communication can afford high throughput demands and flexible deployments with large coverage area, except for their scarce and expensive onboard resources. By introducing a shadowed-Rice (SR) fading model in this paper, a power allocation scheme is proposed for energy efficiency (EE) and spectrum efficiency (SE) trade-off in the multi-beam satellite system with co-channel...
Heterogeneous deployment of base stations with different transmit power levels helps increase the network efficiency. Yet, the allocation of powers to base stations should be optimal in order to minimize interferences and thus improve users through-put. In this paper, we present a game theoretical approach to maximize the overall throughput in heterogeneous networks with optimal power allocation....
This paper we evaluates the performance of multiuser multiple input and multiple outputs (MU-MIMO) detection schemes. MIMO transmissions schemes include transmit diversity and spatial multiplexing and MIMO detection schemes such as zero forcing and soft spheres decoding (SSD). The performance metrics considered are throughput and bit error rate (BER) and these are used to evaluate the performance...
Physical layer network coding (PNC) is a promising technique used to improve the network throughput in a wireless two-way relay (TWR) channel. In this paper, the PNC technique is embraced for a TWR-free space optical (FSO) communication link for the full utilization of network resources. Such a scheme is particularly useful in situations where multiple nodes wish to exchange their information but...
Several test methodologies have been proposed to evaluate the over-the-air (OTA) performance of multiple-input multiple-output (MIMO)-enabled LTE devices. Reproducible data throughput measurements as a function of downlink power are very time consuming for faded radio channels. Thus only a limited number of spatial channel parameters can be evaluated characterizing the OTA performance of a user equipment...
This research addresses the issue of resource and power allocation in small cell networks, and focuses on two aspects: i) the interference coordination among cells; and ii) the resource allocation among the users served by the same cell. Due to the density of small cells, centralised interference coordination schemes require an enormous level of communication among cells. Fuzzy logic (FL) is a promising...
The throughput of small cell networks (SCNs) is limited by intercell interference. Except numerous techniques of interference coordination, simply caching several popular files at each user provides an alternative approach to reduce interference by pre-offloading. This becomes possible nowadays due to the facts that the cost of memory devices is reducing quickly and content delivery is gradually dominating...
Wireless industry through 3G Partnership Project (3GPP), and CTIA The Wireless Association has been studying, validating, and standardizing the 2×2 MIMO Downlink OTA tests since 2009. Especially, CTIA has already provided the guidelines for the MIMO OTA tests in both the Spatial Multiplexing, and Transmit Diversity scenarios [1]. After highlighting some background of the well-documented Spatial Fading...
We consider a slow fading three-node network consisting of a source, a half-duplex decode-and-forward relay, and a destination, where a direct link between the source and the destination does not exist. We assume that the half-duplex relay is equipped with a buffer and employs in each time slot adaptive scheduling of reception and transmission based on the instantaneous qualities of the source-to-relay...
Recently, the V2X communication is a rising technology for driving safety and infotainment services. The considered infotainment services are position tracking, remote diagnostics, accident detection, and multimedia. However, the bandwidth for V2X communication is fixed so that there are some restrictions to support such infotainment services. Therefore, a high data rate V2X communication is required...
In this paper, we investigate the performance of free space optical (FSO) systems with a multiuser scheme employing select-max scheduling technique. Specifically, we consider an FSO communication system which employs a central node equipped with N transmit apertures, each of which aimed to any of the users. Under the assumption of log-normal turbulence channels, we derive closed-form outage capacity...
A variety of forwarding strategies have been developed for multi-hop wireless networks, considering the broadcast nature of the wireless medium and the presence of fading channels that result in time-varying and unreliable transmission quality. One such strategy is opportunistic forwarding, which exploits relay diversity by opportunistically selecting an overhearing relay as a forwarder. Prior work...
This paper focuses on the beneficial effects brought by the presence of multiple receivers to a slotted Aloha scheme. Starting from an analytical angle, we review and compare some recent results that characterize the throughput of such systems under different channel models, based on the assumption that incoming powers at receivers follow an i.i.d. distribution. While practical in some scenarios,...
In this paper, we propose an energy efficient cross-layer design framework for transmitting Markov modulated Poisson process (MMPP) traffic over Nakagami-m fading channel with delay demands. The adaptive modulation and coding (AMC) is used at physical layer. We first investigate the stationary distribution of this system. With the stationary distribution and the AMC transmission mode, we derive the...
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