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High fluctuation of signal strength is evident in wireless channel under mobile environment. IEEE 802.11n and IEEE 802.11ac based wireless technologies experience a challenge for selecting link configuration parameters, like number of spatial streams, channel bonding, advanced modulation and coding schemes, frame aggregation etc., dynamically under mobility. Selection of the best possible data rate...
ITU-R M.1842-1, which is one of the renowned specification for VHF data exchange system (VDES) devoted to maritime mobile applications, has been standardized wireless transmission protocols according to the peculiar characteristics of a maritime communications scenario. Generally, in the Annex-4 of ITU-R M.1842-1, the VHF data link protocols for maritime mobile services are described along with a...
This paper provides a thorough analysis of the key aspects affecting the capacity of LTE networks. We group the analysis to the three major categories namely technology, spectrum and topology aspects. Through the extensive system-level simulations we investigate which of the specified aspects mostly affect the capacity and spectrum efficiency of 4G LTE networks. In addition, based on the performed...
Presented is a method to produce a 2D reference test zone for over-the-air measurements in a random line-of-sight environment for vehicular applications. The ideal threshold receiver model is used to design the chamber array at 3 GHz for LTE/LTE-A systems. The analysis focuses on the fluctuations of the reference power measurements at a user-defined probability of detection level of bit-streams. Numerical...
The aim of this paper is to introduce the measurement method for challenging Non-Line of Sight (NLOS) conditions in mobile networks. The need to develop the measurement method appeared LTE (Long Term Evolution) uplink (UL) performance with different antenna technologies when receiving NLOS signal in field tests. Many challenges appeared during the study. This paper introduces the challenges and presents...
This paper presents a technique to increase the data throughput in Multiple Input Multiple Output (MIMO) systems. The technique uses a meta-heuristic to optimize the data throughput and to choose the best solution. The optimization is based on Genetic Algorithms (GA), with the objective of finding out the best antenna configuration to achieve the highest data throughput from the variation of the distance...
This paper proposed a radiated two-stage based method for the Multiple Input Multiple Output (MIMO) system evaluations. By using the proposed method, not only the final throughput values, but also the antenna patterns, the antennas' envelope correlation coefficient, the antennas' imbalance and the radiated sensitivity of the MIMO device can be obtained over the air. Moreover, through these parameters,...
The intermediate results in Stage I of the RTS method can be used to help evaluate the quality of the designed MIMO antennas, which can benefit engineers with the debugging process for MIMO systems. This is achieved by exploiting the obtained intermediate results to calculate some metrics including envelope correlation coefficient (ECC) and antenna gain imbalance (AGI). The detailed process is described...
Currently and due to its wide use, the wireless networks in conformance with IEEE 802.11 standard are generating channels saturation, that provokes interference between themselves. IEEE 802.11n is one of the standards that offers greater benefits to improve the wireless network performance. In this paper we analyze the performance of wireless network in conformance with IEEE 802.11n standard to evaluate...
Massive multiple input multiple output (MIMO) has emerged as a promising technology, which utilizes a large number of antennas at base stations (BSs) to significantly improve the spectral efficiency in terms of bits/s/Hz while reducing the radiated signal power. A critical issue with massive MIMO is the costly circuit power consumption, which is proportional to the number of antennas. This paper develops...
We propose an optimal Physical Layer Convergence Procedure Protocol Data Unit (PPDU) duration algorithm that divides a long data stream into two portions among consecutive groups based on the average PPDU duration of the Very High Throughput (VHT) group. The proposed solution considers all Wireless Local Area Network (WLAN) parameters and satisfies requirements of the VHT Multi-User Multiple Input...
A Multi Element Antenna (MEA) is an array of antennas that can be driven independently so as to, among other things, mitigate adverse and variable propagation environment effects. MEAs are employed routinely by Multiple Input Multiple Output (MIMO) wireless systems and their effective radiation pattern is controlled by smart algorithms. As such, optimal MEA design cannot rely on traditional specifications...
Non-Orthogonal Multiple Access (NOMA) has proven itself as a serious candidate for multiple access schemes in the 5th generation of wireless communication systems. In this paper, we propose new resource allocation techniques that allow the coupling of NOMA with multiple-input-multiple-output (MIMO) systems. As in most of downlink NOMA systems, the proportional fairness (PF) scheduler is used. As for...
In this paper, energy efficient transmit antenna selection in underlay cognitive radio (CR) multiple-input multiple-output (MIMO) systems from a cross layer perspective, is investigated. Conventional energy efficient antenna selection optimizes an energy efficiency (EE) metric defined in terms of the system capacity and energy consumption, making it a physical layer criterion. In this work, we propose...
Coordinated multi-point transmission can provide high spectral efficiency for cellular systems. However, along with the increment in the amount of data, backhaul gradually becomes the bottleneck in terms of system performance and cost. In this paper, the backhaul delay is mainly focused in coordinated cellular networks and a hybrid channel prediction (HCP) algorithm is proposed. This algorithm combines...
This paper presents field trial results of innovative air interface technologies: sparse code multiple access (SCMA), filtered orthogonal frequency division multiplexing (f-OFDM), and massive multiple-input multiple-output (MIMO). To confirm the improvement of the promising technologies, the counterparts in long term evolution (LTE) are selected as the comparison baseline. For each technology, detailed...
This paper presents field experiments on the downlink throughput performance of a 5G centimeter wave radio access system employing higher rank MIMO in a shopping mall environment and a long corridor environment. The shopping mall has complex reflection paths within its non-line-of-sight areas. The long corridor environment exhibits line-of-sight propagation with many reflection paths. The results...
In this paper, a Virtual Drive Testing (VDT) methodology for a MIMO LTE Vehicle to Infrastructure (V2I) urban scenario is proposed and compared with actual road drive tests. We have developed a unique and generic radio performance analysis process based on 3D ray traced channel models, theoretic or measured antenna patterns, RF channel emulation and hardware-in-the-loop radio measurements. A 3D ray-tracing...
In this paper, we analyze the performance of the fractional pilot reuse (FPR) scheme with vertical sectorization in massive multiple-input multiple-output (MIMO) system. In this scheme, users are classified into the cell-center ones in inner vertical sector and the cell-edge ones in outer vertical sector according to their signal-to-interference-plus- noise ratios (SINRs) at the receiver side. Then,...
Capacity-coverage tradeoff balancing is a classical but critical problem for practical wireless multi- cell network optimization. Increasing the average capacity is often at the expense of decreasing the cell coverage and vice versa. It becomes more complex in massive multiple-input/multiple-output (MIMO) networks to balance the above two performance indicators since capacity is much highly improved...
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