{'fraction_non_alphanumeric': 0.029385574354407838, 'fraction_numerical': 0.0017809439002671415, 'mean_word_length': 4.6767676767676765, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Modeling and Design of a Novel Backward-Wave CPW-Antenna Based on Negative Refractive Index

A new field of physics has appeared with the emergence of materials known as ldquoleft handed materialsrdquo (LHM) or ldquometamaterialsrdquo. These materials show very particular characteristics. Their index of refraction has a negative value, which results in the reversal of Snell's law. Whereas in traditional materials, the Poynting vector S always forms a right-handed triplet with E and H (S = E ^ H). In the left handed media, the Poynting vector S and the wave vector K are in opposite directions. Thus, the wave moves in the direction opposite to the direction of the energy flow: phase speed and group speed are anti-parallel. Therefore, a left-handed media is artificial and does not exist in nature. Indeed, when these materials are inserted into a guided wave device, one obtains the backward wave effect. The goal of this work is to study more in details this physical phenomenon. To undertake this study, this paper presents also the design of a 10 GHz beam-scanning CPW-antenna fabricated on metamaterial support.