Analysis of new active antenna with a patch as feed-back network, using the NDF Method Articles uri icon

publication date

  • January 2016

start page

  • 1763

end page

  • 1772


  • 13


  • 30

International Standard Serial Number (ISSN)

  • 0920-5071

Electronic International Standard Serial Number (EISSN)

  • 1569-3937


  • This paper shows the design of an active patch antenna. First, an analysis of the electric field inside the patch is performed to determine the compatibility of the modes of the patch with the desired feeding. The desired feeding is as a serial two-port resonator, so the suitable mode is the Mode 1. Then a linear analysis of the active antenna is performed. In this particular example, it is possible to use the classic Loop Gain Method, but its use is not guaranteed. So, the proposed NDF Method is used because it is independent of the oscillator topology and it is valid without any restriction or proviso. Then a Harmonic Balance analysis is performed and the results are compared with the measurements of a prototype.


  • ndf; patch antennas; active antennas; oscillators; loop gain; stability criteria; feed-back; microwave circuits; oscillator design; s-parameters; ndf/rrt