Vol. 45

Front:[PDF file] Back:[PDF file]
Latest Volume
All Volumes
All Issues

A Matched Triaxial Device for Cable Shielding Measurements

By S. Sali
Progress In Electromagnetics Research, Vol. 45, 21-44, 2004


A matched triaxial device is designed and constructed to measure the transfer impedance of braided coaxial cables at UHF frequencies. Full design principles of the device have been theoretically developed and the details were given in the paper. The device is particularly suited for accurate measurements of transfer impedances at higher radio frequencies up to 3.8 GHz, for which no comparable technique exists. The performance of the device is evaluated by comparing the results against those obtained from low frequency IEC's triple coaxial apparatus and those obtained by using well known theoretical models.


S. Sali, "A Matched Triaxial Device for Cable Shielding Measurements," Progress In Electromagnetics Research, Vol. 45, 21-44, 2004.


    1. IEC PUBLICATIONS 96.1, "Screening efficiency," IEC working group doc, No. SE22/A/WG5, 1967.

    2. Fowler, E. P., "Test rings for ZT measurements at high frequency," IEC Working Group document, No. SC46/A/WGl (Fowler 2), 1973.

    3. Martin, A. R. and M. Mendenhall, "A fast accurate and sensitive method for measuring surface transfer impedance," IEEE Trans., Vol. EMC-26, 66-70, 1980.

    4. Madle, P. J., "Contact resistances and porpoising effects in braided shields," IEEE Trans., Vol. EMC-23, No. 1, 231-236, 1980.

    5. Goldberg, J. L. and R. J. Slaugther, Braid construction and attenuation of coaxial cables at microwave frequencies, Proc. IEE, Vol. 113, No. 6, 384-389, 1966.

    6. Sali, S., "Coupling problems in a system of multicoaxial cables in homogeneous and inhomogeneous medium," Ph.D. Thesis, No. 10, 1982.

    7. Tyni, M., The transfer impedance of coaxial cables with braided conductors, EMC Symposium, 22-24, 1976.

    8. Bayrak, M. and F. A. Benson, Intermodulation products from nonlinearities in transmission lines at microwave frequencies, Proc. IEE, Vol. 122, No. 4, 361-367, 1975.

    9. Sali, S., "Screening efficiency of triaxial cables with optimum braided shields," IEEE Trans., Vol. EMC-42, No. 8, 26-33, 1991.

    10. Kraus, A., "Reflection coefficient curves of compensated discontinuities on coaxial line and determination of optimum dimensions-Part II," Journal of British Inst. of Radio Eng., Vol. 5, No. 5, 365-372, 1962.

    11. Fowler, E. P., ''Observations on the use of ZT(C) for comparing the breakthrough capacitance of cable braids, No. '' IEC Working Group document SC46/A/WG1 (Fowler 3), '' IEC Working Group document No. SC46/A/WG1 (Fowler 3), 1973.

    12. Homann, E., "Geschirmte kabel mit optimalen geflectschirmen," Nachrichtentechnishe Zeitschrift, Vol. 21, No. 3, 155-161, 1968.

    13. Schelkunoff, S. A., "The electromagnetic theory of coaxial transmission lines and cylindrical shields," Bell System Technical Journal, Vol. 13, No. 4, 532-578, 1934.