Multiple frequency printed slot and dipole antennas

Abstract

Multiple frequency antennas are becoming more and more important as the technology advances. Printed circuit antennas can be designed to achieve multiple frequency operation. The advantages like low cost, conformal and planar, and a possible combination of integrating solid-state devices on the same substrate as the antenna makes printed circuit antennas highly attractive. An improved less rigorous transmission line model is used to analyze microstrip-fed transverse slot antennas. Adding a frequency dependent correction factor improves the accuracy of predicting the operation frequency. The CPW-fed CPS dipoles need a wide band balun as transition between the CPW and CPS transmission lines. The use of available commercial fullwave EM simulator programs, such as Sotinet and IE3D, can analyze the behavior of the large and complex overall circuit structure. In corn parison with microstrip-fed slot antennas which could have two operation frequencies, a CPW-fed CPS-dipole could have several operation frequencies. Adding one varactor diode to the slot antenna or two diodes to the dipole either switching or tuning of the antenna could be achieved.