منابع مشابه
Maximum likelihood separation of constant modulus signals
In this paper we derive a Newton scoring algorithm for the maximum likelihood separation and directionof-arrival estimation of constant modulus (CM) signals, using a sensors array. We present a rapidly converging scheme for the joint estimation of the signals and their directions, based on their CM property. We discuss initialization and show that the complexity is moderate. 2
متن کاملOn the Maximum Modulus of Polynomials. Ii
Let f(z) := ∑n ν=0 aνz ν be a polynomial of degree n having no zeros in the open unit disc, and suppose that max|z|=1 |f(z)| = 1. How small can max|z|=ρ |f(z)| be for any ρ ∈ [0 , 1)? This problem was considered and solved by Rivlin [4]. There are reasons to consider the same problem under the additional assumption that f ′(0) = 0. This was initiated by Govil [2] and followed up by the present ...
متن کاملOn the Structure of Maximum Modulus Algebras
i.e., if every fER attains its maximum modulus on C. As a matter of convenience, we shall, in this paper, abbreviate "maximum modulus algebra on K" to "ilf-algebra." Examples of Af-algebras which come to mind immediately are (a) the algebra ft consisting of all functions which are continuous on K and analytic in U, (b) any subalgebra of ft, (c) any algebra (B which is equivalent to an algebra o...
متن کاملThe maximum modulus of a trigonometric trinomial
Let Λ be a set of three integers and let CΛ be the space of 2π-periodic functions with spectrum in Λ endowed with the maximum modulus norm. We isolate the maximum modulus points x of trigonometric trinomials T ∈ CΛ and prove that x is unique unless |T | has an axis of symmetry. This permits to compute the exposed and the extreme points of the unit ball of CΛ, to describe how the maximum modulus...
متن کاملThe fractionally spaced vector constant modulus algorithm
The vector constant modulus algorithm (VCMA) was recently introduced as an extension of CMA which can equalize data from shaped sources having nearly Gaussian marginal distributions. Some simple changes in the structure of VCMA allow it to be used in fractionally-spaced equalizers with their attendant benefits. Although developed with shell mapping in mind, VCMA can also equalize data from othe...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1951
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1951-0040450-8