The Weil transform and ambiguity functions.

Item

Title
The Weil transform and ambiguity functions.
Identifier
AAI9325098
identifier
9325098
Creator
Geshwind, Frank B.
Contributor
Adviser: Louis Auslander
Date
1993
Language
English
Publisher
City University of New York.
Subject
Mathematics
Abstract
Recall that the Weil transform, {dollar}\Theta,{dollar} is an intertwining operator between the {dollar}{lcub}\bf L{rcub}\sp2{dollar} Dirac representation D, of the real, 3-dimensional Heisenberg group, {dollar}{lcub}\cal N{rcub},{dollar} and the regular representation of {dollar}{lcub}\cal N{rcub}{dollar} on {dollar}{lcub}\bf L{rcub}\sp2(\Gamma\\{lcub}\cal N{rcub}),{dollar} where {dollar}\Gamma{dollar} is the integer Heisenberg group. As such, it provides a unitary isomorphism between {dollar}{lcub}\bf L{rcub}\sp2({lcub}\bf R{rcub}){dollar} and {dollar}{lcub}\bf L{rcub}\sp2(\Gamma\\{lcub}\cal N{rcub}).{dollar}.;In this work, the definition of {dollar}\Theta{dollar} is extended so that its domain includes various types of distributions. Results in the literature relating smoothness and moments of functions on R to smoothness and moments of the corresponding functions on {dollar}\Gamma\\{lcub}\cal N{rcub},{dollar} are extended to distributions.;A study of the local structure of smooth functions in {dollar}\Theta({lcub}\bf L{rcub}\sp2({lcub}\bf R{rcub})){dollar} is carried out. A product theorem is given for certain functions which we describe as having smooth growth. Theorems are given about the local homology of these functions. These results are applied to the problem of dividing smooth functions in {dollar}\Theta({lcub}\bf L{rcub}\sp2({lcub}\bf R{rcub})){dollar} by each other, which is related to questions of stable Weyl-Heisenberg wavelet expansions for such functions.;The Weil transform and the above insights into smooth functions in {dollar}\Theta({lcub}\bf L{rcub}\sp2({lcub}\bf R{rcub})){dollar} are applied to the thumbtack synthesis problem for radar ambiguity functions. We study known constructions for this problem, in the present context, and then provide new constructions using the insights gained.
Type
dissertation
Source
PQT Legacy CUNY.xlsx
degree
Ph.D.
Item sets
CUNY Legacy ETDs