By Topic

Antennas and Propagation Magazine, IEEE

Issue 6 • Date Dec. 1998

Filter Results

Displaying Results 1 - 8 of 8
  • A tutorial on wavelets from an electrical engineering perspective .2. The continuous case

    Publication Year: 1998 , Page(s): 36 - 49
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (1372 KB)  

    The wavelet transform is described from the perspective of a Fourier transform. The relationships among the Fourier transform, the Gabor (1946) transform (windowed Fourier transform), and the wavelet transform are described. The differences are also outlined, to bring out the characteristics of the wavelet transform. The limitations of the wavelets in localizing responses in various domains are al... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Reviews and Abstracts

    Publication Year: 1998 , Page(s): 72 - 73
    Save to Project icon | Request Permissions | PDF file iconPDF (238 KB)  
    Freely Available from IEEE
  • Parameters of a multiple-arm spiral antenna from single-arm measurements

    Publication Year: 1998 , Page(s): 65 - 69
    Cited by:  Papers (3)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (520 KB)  

    Multiple-arm spiral antennas, generally with four or more arms, can be fed in multiple modes that produce different antenna patterns. The patterns and S-parameters of the antenna, operating in different modes, can be found by combining a weighted sum of measurements made on individual arms. The frequency range of good efficiency can be determined from S-parameter measurements before the antenna pa... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Measuring the impedance of balanced antennas by an S-parameter method

    Publication Year: 1998 , Page(s): 62 - 65
    Cited by:  Papers (37)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (328 KB)  

    The input impedance of a balanced antenna is conventionally measured by using a balun that forces opposite currents in each part of the radiator. In this paper, balanced antennas are viewed as two-ports, the S-parameters of which are determined by standard network-analyzer techniques. Simple formulas then lead to the differential input impedance. The method is illustrated by measurements on a dipo... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Electromagnetic scattering by a wedge with anisotropic impedance faces

    Publication Year: 1998 , Page(s): 29 - 35
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (996 KB)  

    Electromagnetic scattering from the edge of an anisotropic impedance wedge, illuminated at oblique incidence, is addressed. In particular, the paper provides a review of existing solutions for this important topic in diffraction theory. Both numerical and analytical techniques, suitable to properly account for the scattering properties of the wedge's anisotropic impedance faces, are considered View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Avanced Communications Technology Satellite (ACTS) propagation campaign in North America

    Publication Year: 1998 , Page(s): 23 - 28
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (640 KB)  

    Ka-band propagation measurements with the Advanced Communications Technology Satellite (ACTS) are entering their fifth year of data collection. Beacon-signal levels and radiometric sky noise are being measured at 20.2 and 27.5 GHz, with supporting meteorological information, at seven experiment sites in the US and Canada, using ACTS propagation terminals (PSTs) supplied by NASA. Uniform system-cal... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Electromagnetics in magnetic resonance imaging

    Publication Year: 1998 , Page(s): 7 - 22
    Cited by:  Papers (3)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (1600 KB)  

    Magnetic resonance imaging (MRI) is a powerful new imaging method, which produces cross-sectional tomographic and three-dimensional images similar to those of x-ray computed tomography (CT). However, rather than relying on harmful ionizing radiation, MRT is based on the interaction between RF fields and certain atomic nuclei in the body, when they are in the presence of a strong magnetic field. An... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Evaluation of capacitance with prescribed accuracy adaptive method based on exact error estimation

    Publication Year: 1998 , Page(s): 80 - 84
    Save to Project icon | Request Permissions | Click to expandAbstract | PDF file iconPDF (432 KB)  

    This paper presented an adaptive method for a two-dimensional electrostatic analysis of air-filled two-conductor lines. The method is based on exact error estimates, and thus enables the evaluation of capacitance within prescribed accuracy limits. For the example of a transmission line consisting of square conductors considered, the characteristic impedance was estimated to be Z=75 ohms with a pre... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

The IEEE Antennas and Propagation Magazine actively solicits feature articles that describe engineering activities taking place in industry, government, and universities

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Mahta Moghaddam