Comments on Deficiencies in the way scattering parameters are Taught

Dipt. di Sistemi Elettrici e Automazione, Univ. di Pisa, Italy
IEEE Transactions on Education (Impact Factor: 0.84). 03/2006; 49(1):176 - 178. DOI: 10.1109/TE.2005.858402
Source: IEEE Xplore


Equivalent representation of multiport circuits by the use of scattering parameters is of fundamental importance, especially in the microwave circuits area. However, in most cases, only a few pages of textbooks are devoted to this topic; based on the author's experience, the students find it somehow difficult to understand the physical meaning of scattering parameters (while they find other representations, like Z, Y, hybrid, or transmission parameters, easy to understand). For this reason, the contribution given by Sadiku (IEEE Trans. Educ., Vol. 46, no. 3, Aug. 2003, pp. 399-404) is very important. Furthermore, in Sadiku's paper, three nontrivial examples are reported, through which the students can gain understanding of this fundamental tool. In two of the three examples, some points are unclear; this correspondence analyzes this lack of clarity.

1 Read
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A miniaturized Wilkinson power divider using three-dimensional (3-D) monolithic microwave integrated circuit (MMIC) technology is presented. The new power divider utilizes stacked thin film microstrip (TFMS) lines that sandwich a ground plane with a slit between the TFMS lines. The slit effectively widens the upper and lower TFMS-line widths, which makes it possible to stack high-impedance lines with a reasonable conductor strip width and lower loss. The proposed structure also exhibits a coupling between the quarter-wavelength conductor strips of less than -15 dB, simplifying the design for each TFMS line. A fabricated 15-25 GHz Wilkinson power divider, the area of which is only 0.31 mm×0.52 mm, exhibits a coupling of -4.5±0.5 dB, isolation of greater than 15 dB, and a phase deviation of less than 3 degrees
    IEEE Microwave and Guided Wave Letters 11/1996; 6(10-6):372 - 374. DOI:10.1109/75.536949
  • Radio and Electronic Engineer 01/1984; 54. DOI:10.1049/ree.1984.0110
  • [Show abstract] [Hide abstract]
    ABSTRACT: The scattering parameters are fundamental in the characterization of electrical devices at high frequencies. They are particularly useful for analyzing multiport high-frequency and microwave networks. However, they are not adequately presented in most, if not all, microwave engineering books. This paper identifies two common deficiencies in the way scattering parameters are being presented in these books. It provides additional information that should supplement those books or book chapters on scattering parameters.
    IEEE Transactions on Education 09/2003; 46(3-46):399 - 404. DOI:10.1109/TE.2003.815233 · 0.84 Impact Factor