Effect of Directional Antenna on the Doppler Spectrum in 3-D Mobile Radio Propagation Environment

In this paper, an analytical model is proposed for a macrocellular communication system with directional antennas at elevated base station (BS) to quantify the effect of directivity of the radiated waves from antennas on the Doppler spectrum in a 3-D radio propagation environment. The impacts of ant...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on vehicular technology 2011-09, Vol.60 (7), p.2895-2903
Main Authors: Nawaz, S. J., Khan, N. M., Patwary, M. N., Moniri, M.
Format: Article
Language:English
Subjects:
Antennas
Applied sciences
Azimuth
Diffraction, scattering, reflection
Directional antennas
Directive antennas
Doppler
Doppler effect
Doppler shift
Equipments and installations
Exact sciences and technology
Genetic expression
geometric modeling
Joints
land mobile radio
Mathematical analysis
Mobile radiocommunication systems
path loss
Probability density functions
radio propagation
Radiocommunications
Radiowave propagation
Scattering
Stations
Studies
Telecommunications
Telecommunications and information theory
Three dimensional
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this paper, an analytical model is proposed for a macrocellular communication system with directional antennas at elevated base station (BS) to quantify the effect of directivity of the radiated waves from antennas on the Doppler spectrum in a 3-D radio propagation environment. The impacts of antenna beamwidth and motion of mobile station (MS) are thoroughly investigated on the statistical distribution of the power Doppler spectrum. Closed-form expressions for trivariate probability density functions (pdfs) of propagation path distance, power, and Doppler shift are derived. Furthermore, general expressions for joint and marginal pdfs of elevation angle of arrival, power, and Doppler shift are established. Finally, the obtained theoretical results, along with the observations that illustrate the effect of directivity of the antenna beamwidth and the direction of the MS's motion on the distribution characteristics of the power Doppler spectrum, are presented. It is established that for motion of the MS in all directions, the spread in distribution of the Doppler shift observed is significantly reduced due to the use of a directional antenna at the BS with a narrow beam directed toward the desired user. It is also observed that, for a sharp azimuthal beam of directional antenna, the multipath components corresponding to the scatterers in the elevation plane result in the reduction of Doppler shift with an increase in their vertical distance from the MS.
ISSN:0018-9545
1939-9359
DOI:10.1109/TVT.2011.2161788