This paper presents study of controllable leaky wave modes in various planar transmission lines operating at millimetre wavelengths. Leaky wave regime is achieved by exploitation of periodic inclusions. The main goal is to obtain the scanning of the radiation angle from forward to backward direction and rather broad range of scanning angles at a given operation frequency corresponding to the mm-wave range. For this purpose we suggest to use MEMS capacitors combined with shunt strap inductors, probably grounded. This design solution allows one to significantly reduce the losses in the loaded line compared to known scanning leaky-wave antennas based on varactors or on magnetized ferrites. The design of the unit cell is done using global optimization method, and the dispersion is investigated analytically. After analytical modeling and optimization, full wave analysis is done using Ansoft HFSS v.11 environment. After the leaky wave regimes are verified, an example of a leaky-wave antenna is introduced in order to confirm possibility of beam scanning.
Antti V. Räisänen,
Constantin R. Simovski,
"Leaky-Wave Regimes on MEMS-Loaded Transmission Lines for mm
-Wave Applications," Progress In Electromagnetics Research M,
Vol. 13, 157-171, 2010. doi:10.2528/PIERM10050605
1. Bagley, Q., B. Wu, and L. Tsang, "Electromagnetic fields of hertzian dipoles in layered negative refractive index materials," IEEE Antennas Wirel. Propag. Lett., Vol. 7, 749-752, 2008. doi:10.1109/LAWP.2008.2008031
2. Grbic, A. and G. V. Eleftheriades, "Leaky CPW-based slot antenna arrays for millimeter-wave applications," IEEE Trans. Antennas Propag., Vol. 50, No. 11, 1494-1504, 2002. doi:10.1109/TAP.2002.804259
3. Hanson, G. W. and A. B. Yakovlev, "Leaky wave excitation on three-dimensional printed interconnects," IEEE MTT-S Digest, Vol. 2, 499-502, 2004.
4. Diamantis, S. G., G. A. Kyriacou, A. A. Mavrides, and J. N. Sahalos, "Investigation of eigen-backward and leaky-waves modes of an axially magnetized lossy cylindrical ferrite substrate," XXVIIth General Assembly of the International Union of Radio Science, No. 1270, 17-24, Maastricht, Aug. 2002.
5. Subramanyam, G., F. Ahamed, R. Biggers, R. Neidhard, E. Nykiel, J. Ebel, R. Strawser, K. Stamper, and M. Calcatera, "RF performance evaluation of ferroelectric varactor shunt switches," Microwave Opt. Technol. Lett., Vol. 47, No. 4, 370-374, 2005. doi:10.1002/mop.21172
6. Gil, I., J. Bonache, J. Garca-Garca, F. Martn, and R. Marques, "Tunable split ring resonators for reconfigurable metamaterial transmission lines," IEEE Trans. Microwave Theory Tech., Vol. 54, No. 6, 2665-2674, 2006. doi:10.1109/TMTT.2006.872949
7. Ojefors, E., S. Cheng, K. From, I. Skarin, P. Hallbjorner, and A. Rydberg, "Electrically steerable single-layer microstrip traveling wave antenna with varactor diode based phase shifters," IEEE Trans. Antennas Propag., Vol. 55, No. 9, 2451-2460, 2007. doi:10.1109/TAP.2007.904104
8. Piazza, D., M. D'Amico, and K. R. Dandekar, "Two port configurable CRLH leaky wave antenna with improved impedance matching and beam tunning," Proc. of the European Conference on Antennas and Propagation, 2046-2049, Berlin, March 23-27, 2009.
9. Rebeiz, G. M., RF MEMS Theory, Design, and Technology, John Wiley & Sons, Inc. Publication, 2003.
10. Simovski, C., "Bloch material parameters of magneto-dielectric metamaterials and the concept of Bloch lattices," Metamaterials, Vol. 1, No. 2, 62-80, 2007. doi:10.1016/j.metmat.2007.09.002
11. Robinson, J. and Y. Rahmat-Samii, "Particle swarm optimization in electromagnetics," IEEE Trans. Antennas Propag., Vol. 52, No. 2, 397-407, 2004. doi:10.1109/TAP.2004.823969
12. Caloz, C., A. Lai, and T. Itoh, "The challenge of homogenization in metamaterials," New J. Phys., Vol. 7, 167-182, 2005. doi:10.1088/1367-2630/7/1/167
13. Caloz, C. and T. Itoh, Electromagnetic Metamaterials Transmission Line Theory and Microwave Applications, John Wiley & Sons, Inc. Publication, 2006. doi:10.1002/0471754323
14. Varadan, V. K., K. J. Vinoy, and K. A. Jose, "RF MEMS and Their Applications," John Wiley & Sons Ltd, 2002.
15. Chicherin, D., M. Sterner, J. Oberhammer, S. Dudorov, J. Aberg, and A. V. Raisanen, "Analog type millimeter wave phase shifters based on MEMS tunable high-impedance surface in rectangular metal waveguide ," IEEE MTT-S Digest, 61-64, May 23-28, 2010.
16. Pozar, D. M., "Microwave Engineering," John Wiley & Sons, Inc. Publication, 1998.