Diversely polarized antenna array systems
Author(s)
Supakwong, Supawat
Type
Thesis
Abstract
This thesis is concerned with the use of diversely polarized antennas in an array
system as the advantage of this array architecture over a uniformly polarized
array is its capability to separate multiple signals based on their polarization
characteristics. Overall system performance is substantially improved due to
an extra degree of signal discrimination. In this thesis, the aim is to address
and explore several issues regarding the employment of the diversely polarized
antennas in order to assess the array performance and its characteristics.
First of all, the geometrical properties of the array manifold associated with
polarization-sensitive array are explored from the differential geometry perspective. The fact that the array manifold incorporates all information about the
array and signal environments allows it to completely characterize the whole system. In this work, a new mathematical framework is proposed to analyze three-
parameter diversely polarized manifold, where important notations to describe
the local characteristics of the manifold are provided.
Second, issues regarding the presence of uncertainties in polarization-sensitive
arrays are investigated. The array system considered so far is assumed to be free
from errors and uncertainties. However, in practice, the system performance
is affected considerably by various types of uncertainties that deviate from the
assumed conditions. A framework based on the sensitivity analysis of manifold
shape property is presented to evaluate the array robustness to uncertainties. In
addition, a novel calibration method is proposed utilizing the concept of diversely
polarized manifold.
Third, problems regarding the presence of manifold ambiguities are addressed.
Manifold ambiguity is an undesirable situation often encountered when there exists linear dependence amongst array response vectors. This study aims to investigate issues regarding the identification, classification, as well as the eradication
of some types of ambiguities. A general framework to identify diversely polarized manifold ambiguity is presented, followed by two novel techniques to resolve
ambiguities.
Finally, issues regarding the use of polarization-sensitive antennas in CDMA-
based systems are addressed. The framework is essentially based on an integration of polarization-sensitive antennas, space-time array processing, and the
spread-spectrum multiple access technology. First, the properties of Polarization-
Spatio-Temporal ARray (Polar-STAR) manifold is investigated based on a direct
relationship with the diversely polarized manifold. Then, the array's ultimate
detection capabilities are presented. Finally, a self calibration method for a
polarization-sensitive asynchronous DS-CDMA system is proposed.
system as the advantage of this array architecture over a uniformly polarized
array is its capability to separate multiple signals based on their polarization
characteristics. Overall system performance is substantially improved due to
an extra degree of signal discrimination. In this thesis, the aim is to address
and explore several issues regarding the employment of the diversely polarized
antennas in order to assess the array performance and its characteristics.
First of all, the geometrical properties of the array manifold associated with
polarization-sensitive array are explored from the differential geometry perspective. The fact that the array manifold incorporates all information about the
array and signal environments allows it to completely characterize the whole system. In this work, a new mathematical framework is proposed to analyze three-
parameter diversely polarized manifold, where important notations to describe
the local characteristics of the manifold are provided.
Second, issues regarding the presence of uncertainties in polarization-sensitive
arrays are investigated. The array system considered so far is assumed to be free
from errors and uncertainties. However, in practice, the system performance
is affected considerably by various types of uncertainties that deviate from the
assumed conditions. A framework based on the sensitivity analysis of manifold
shape property is presented to evaluate the array robustness to uncertainties. In
addition, a novel calibration method is proposed utilizing the concept of diversely
polarized manifold.
Third, problems regarding the presence of manifold ambiguities are addressed.
Manifold ambiguity is an undesirable situation often encountered when there exists linear dependence amongst array response vectors. This study aims to investigate issues regarding the identification, classification, as well as the eradication
of some types of ambiguities. A general framework to identify diversely polarized manifold ambiguity is presented, followed by two novel techniques to resolve
ambiguities.
Finally, issues regarding the use of polarization-sensitive antennas in CDMA-
based systems are addressed. The framework is essentially based on an integration of polarization-sensitive antennas, space-time array processing, and the
spread-spectrum multiple access technology. First, the properties of Polarization-
Spatio-Temporal ARray (Polar-STAR) manifold is investigated based on a direct
relationship with the diversely polarized manifold. Then, the array's ultimate
detection capabilities are presented. Finally, a self calibration method for a
polarization-sensitive asynchronous DS-CDMA system is proposed.
Date Issued
2009-12
Date Awarded
2010-01
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Constantinides, Anthony
Sponsor
Thai Government
Creator
Supakwong, Supawat
Publisher Department
Electrical and Electronic Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)