8,342 research outputs found
Design of a Planar Eleven Antenna for Optimal MIMO Performance as a Wideband Micro Base-station Antenna
A new low-profile planar Eleven antenna is designed for optimal MIMO
performance as a wideband MIMO antenna for micro base-stations in future
wireless communication systems. The design objective has been to optimize both
the reflection coefficient at the input port of the antenna and the 1-bitstream
and 2-bitstream MIMO efficiency of the antenna at the same time, in both the
Rich Isotropic MultiPath (RIMP) and Random Line-of-Sight (Random-LOS)
environments. The planar Eleven antenna can be operated in 2-, 4-, and 8-port
modes with slight modifications. The optimization is performed using genetic
algorithms. The effects of polarization deficiencies and antenna total embedded
efficiency on the MIMO performance of the antenna are further studied. A
prototype of the antenna has been fabricated and the design has been verified
by measurements against the simulations.Comment: 7 pages, 15 figures, 15 reference
A Novel Millimeter-Wave Channel Simulator and Applications for 5G Wireless Communications
This paper presents details and applications of a novel channel simulation
software named NYUSIM, which can be used to generate realistic temporal and
spatial channel responses to support realistic physical- and link-layer
simulations and design for fifth-generation (5G) cellular communications.
NYUSIM is built upon the statistical spatial channel model for broadband
millimeter-wave (mmWave) wireless communication systems developed by
researchers at New York University (NYU). The simulator is applicable for a
wide range of carrier frequencies (500 MHz to 100 GHz), radio frequency (RF)
bandwidths (0 to 800 MHz), antenna beamwidths (7 to 360 degrees for azimuth and
7 to 45 degrees for elevation), and operating scenarios (urban microcell, urban
macrocell, and rural macrocell), and also incorporates multiple-input
multiple-output (MIMO) antenna arrays at the transmitter and receiver. This
paper also provides examples to demonstrate how to use NYUSIM for analyzing
MIMO channel conditions and spectral efficiencies, which show that NYUSIM is an
alternative and more realistic channel model compared to the 3rd Generation
Partnership Project (3GPP) and other channel models for mmWave bands.Comment: 7 pages, 8 figures, in 2017 IEEE International Conference on
Communications (ICC), Paris, May 201
Improving Bandwidth Efficiency in E-band Communication Systems
The allocation of a large amount of bandwidth by regulating bodies in the
70/80 GHz band, i.e., the E-band, has opened up new potentials and challenges
for providing affordable and reliable Gigabit per second wireless
point-to-point links. This article first reviews the available bandwidth and
licensing regulations in the E-band. Subsequently, different propagation
models, e.g., the ITU-R and Cane models, are compared against measurement
results and it is concluded that to meet specific availability requirements,
E-band wireless systems may need to be designed with larger fade margins
compared to microwave systems. A similar comparison is carried out between
measurements and models for oscillator phase noise. It is confirmed that phase
noise characteristics, that are neglected by the models used for narrowband
systems, need to be taken into account for the wideband systems deployed in the
E-band. Next, a new multi-input multi-output (MIMO) transceiver design, termed
continuous aperture phased (CAP)-MIMO, is presented. Simulations show that
CAP-MIMO enables E-band systems to achieve fiber-optic like throughputs.
Finally, it is argued that full-duplex relaying can be used to greatly enhance
the coverage of E-band systems without sacrificing throughput, thus,
facilitating their application in establishing the backhaul of heterogeneous
networks.Comment: 16 pages, 6 Figures, Journal paper. IEEE Communication Magazine 201
Indoor wireless communications and applications
Chapter 3 addresses challenges in radio link and system design in indoor scenarios. Given the fact that most human activities take place in indoor environments, the need for supporting ubiquitous indoor data connectivity and location/tracking service becomes even more important than in the previous decades. Specific technical challenges addressed in this section are(i), modelling complex indoor radio channels for effective antenna deployment, (ii), potential of millimeter-wave (mm-wave) radios for supporting higher data rates, and (iii), feasible indoor localisation and tracking techniques, which are summarised in three dedicated sections of this chapter
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