948 research outputs found
Computationally Intelligent Techniques for Resource Management in MmWave Small Cell Networks
Ultra densification in HetNets and the advent of mmWave technology for 5G networks have led researchers to redesign the existing resource management techniques. A salient feature of this activity is to accentuate the importance of CI resource allocation schemes offering less complexity and overhead. This article overviews the existing literature on resource management in mmWave-based Het- Nets with a special emphasis on CI techniques and further proposes frameworks that ensure quality of service requirements for all network entities. More specifically, HetNets with mmWave-based small cells pose different challenges compared to an all-microwave- based system. Similarly, various modes of small cell access policies and operations of base stations in dual mode, that is, operating both mmWave and microwave links simultaneously, offer unique challenges to resource allocation. Furthermore, the use of multi-slope path loss models becomes inevitable for analysis due to irregular cell patterns and blocking characteristics of mmWave communications. This article amalgamates the unique challenges posed because of the aforementioned recent developments and proposes various CI-based techniques, including game theory and optimization routines, to perform efficient resource management
A Multiband OFDMA Heterogeneous Network for Millimeter Wave 5G Wireless Applications
Citation: Niknam, S., Nasir, A. A., Mehrpouyan, H., & Natarajan, B. (2016). A Multiband OFDMA Heterogeneous Network for Millimeter Wave 5G Wireless Applications. Ieee Access, 4, 5640-5648. doi:10.1109/access.2016.2604364Emerging fifth generation (5G) wireless networks require massive bandwidth in higher frequency bands, extreme network densities, and flexibility of supporting multiple wireless technologies in order to provide higher data rates and seamless coverage. It is expected that the utilization of the large bandwidth in the millimeter-wave (mmWave) band and deployment of heterogeneous networks (HetNets) will help address the data rate requirements of 5G networks. However, high pathloss and shadowing in the mmWave frequency band, strong interference in the HetNets due to massive network densification, and coordination of various air interfaces are challenges that must be addressed. In this paper, we consider a relay based multiband orthogonal frequency division multiple access HetNet in which mmWave small cells are deployed within the service area of macro cells. In particular, we attempt to exploit the distinct propagation characteristics of mmWave bands (i.e., 60 GHz-the V-band and 70-80 GHz the E-band) and the long term evolution band to maximize overall data rate of the network via efficient resource allocation. The problem is solved using a modified dual decomposition approach and then a low complexity greedy solution based on the iterative activity selection algorithm is presented. Simulation results show that the proposed approach outperforms conventional schemes
Device-to-Device Communications in the Millimeter Wave Band: A Novel Distributed Mechanism
In spite of its potential advantages, the large-scale implementation of the
device-to-device (D2D) communications has yet to be realized, mainly due to
severe interference and lack of enough bandwidth in the microwave (W)
band. Recently, exploiting the millimeter wave (mmW) band for D2D
communications has attracted considerable attention as a potential solution to
these challenges. However, its severe sensitivity to blockage along with its
directional nature make the utilization of the mmW band a challenging task as
it requires line-of-sight (LOS) link detection and careful beam alignment
between the D2D transceivers. In this paper, we propose a novel distributed
mechanism which enables the D2D devices to discover unblocked LOS links for the
mmW band communication. Moreover, as such LOS links are not always available,
the proposed mechanism allows the D2D devices to switch to the W band if
necessary. In addition, the proposed mechanism detects the direction of the LOS
links to perform the beam alignment. We have used tools from stochastic
geometry to evaluate the performance of the proposed mechanism in terms of the
signal-to-interference-plus-noise ratio (SINR) coverage probability. The
performance of the proposed algorithm is then compared to the one of the single
band (i.e., W/mmW) communication. The simulation results show that the
proposed mechanism considerably outperforms the single band communication.Comment: 6 Pages, 6 Figures, Accepted for presentation in Wireless
Telecommunication Symposium (WTS'18
Development of a dc-ac power conditioner for wind generator by using neural network
This project present of development single phase DC-AC converter for wind
generator application. The mathematical model of the wind generator and Artificial
Neural Network control for DC-AC converter is derived. The controller is designed to
stabilize the output voltage of DC-AC converter. To verify the effectiveness of the
proposal controller, both simulation and experimental are developed. The simulation and
experimental result show that the amplitude of output voltage of the DC-AC converter
can be controlled
End-to-End Simulation of 5G mmWave Networks
Due to its potential for multi-gigabit and low latency wireless links,
millimeter wave (mmWave) technology is expected to play a central role in 5th
generation cellular systems. While there has been considerable progress in
understanding the mmWave physical layer, innovations will be required at all
layers of the protocol stack, in both the access and the core network.
Discrete-event network simulation is essential for end-to-end, cross-layer
research and development. This paper provides a tutorial on a recently
developed full-stack mmWave module integrated into the widely used open-source
ns--3 simulator. The module includes a number of detailed statistical channel
models as well as the ability to incorporate real measurements or ray-tracing
data. The Physical (PHY) and Medium Access Control (MAC) layers are modular and
highly customizable, making it easy to integrate algorithms or compare
Orthogonal Frequency Division Multiplexing (OFDM) numerologies, for example.
The module is interfaced with the core network of the ns--3 Long Term Evolution
(LTE) module for full-stack simulations of end-to-end connectivity, and
advanced architectural features, such as dual-connectivity, are also available.
To facilitate the understanding of the module, and verify its correct
functioning, we provide several examples that show the performance of the
custom mmWave stack as well as custom congestion control algorithms designed
specifically for efficient utilization of the mmWave channel.Comment: 25 pages, 16 figures, submitted to IEEE Communications Surveys and
Tutorials (revised Jan. 2018
- …