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A UHF band near-field antenna using microstrip lines and stubs for tagging stacked tags in a smart table is presented. It is shown that a suitable near-field reader antenna can be designed from signal lines, ground lines, and several stubs to generate coupled electric and magnetic fields. The proposed near-field reader antenna satisfactorily operates in a UHF radio frequency identification (RFID) smart table, and the measurements show that the antenna is capable of detecting 200 stacked tags in a reading area of 200 mm × 190 mm and achieves a detection rate of 97% when the tags are stacked in a smart table. The proposed UHF RFID smart table is successfully implemented for casino chip management. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1116–1119, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25115 [ABSTRACT FROM AUTHOR]

Several dielectric as well as conducting pipes buried in the lossy half ground are reconstructed from the scattered fields measured along the air–earth interface. The iterative inversion method using the hybrid optimization algorithm combining the genetic and Levenberg–Marquardt algorithms is used in finding the positions, sizes, and medium parameters, such as the permittivities and conductivities, of the buried pipe cylinders, as well as those of the background lossy half ground. Ill posedness of the inversion caused by the errors in the measured scattered fields is regularized by filtering out the evanescent modes of the scattered fields. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 140–143, 2001. [ABSTRACT FROM AUTHOR]