A new compact multiband PIFA (Planar Inverted-F Antenna) for mobile handset is proposed in this article. The proposed PIFA has a simple geometry with four slots integrated in the radiating patch and ground plane. The PIFA occupies a small volume of 51 × 14 × 7.2 mm3 and is placed on the top portion of mobile phone. The optimized PIFA is worked in the 790 MHz band (737–831 MHz), the 1870 MHz band (1794–1977 MHz), the 2550 MHz band (2507–2615 MHz), and the 3400 MHz band (3341–3545 MHz), to cover LTE700, LTE800, DCS1800, PCS1900, LTE1800, LTE1900, LTE2500, and WIMAX3400 bands. Each of the four operating bands can be controlled independently by the variation of a single parameter of the proposed design, with a wide control range. An omnidirectional radiation pattern to each resonant frequency is obtained with a maximum gain of 2.15 dBi at 790 MHz, 3.99 dBi at 1870 MHz, 4.57 dBi at 2550 MHz, and 6.43 dBi at 3400 MHz. The proposed PIFA is studied in the free space and in the presence of other mobile phone components such as the battery, LCD (liquid crystal display), camera, microphone, speaker, buttons, and a plastic housing. The distribution of specific absorption rate for both European and American standards for each operating band and at various distances between the antenna and the human head is also studied.

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Abstract. The propose device is based on Michelson interferometer. In fact, we put the a sample of cylindrical shape dry clay of length L and radius R on the mobile mirror, This sample can retain a drop of water on its surface in order to monitor water content. When injecting a volume of distilled water (a few drops) to the surface of the sample, it swells and moves the mirror. Consequently, we see scrolling fringes and we proceed to count their number during the time t during this swelling (about 40 min). We can measure the free displacement of the mirror and to establish the value of swelling expressed in% or g/cm 3 , the swelling under stress σ (to compare with the oedometer) and speed during a time t.Résumé. Le dispositif est un interféromètre de Michelson modifié. En effet sur le miroir mobile est collé un échantillon d'argile cylindrique, séché, de longueur L, de rayon R et façonnée de manière à retenir les gouttes d'eau à sa surface pour contrôler la teneur en eau. Lorsqu'on injecte un volume d'eau distillée (quelques gouttes) à la surface de l'échantillon, celui-ci se gonfle et le miroir se déplace. On observe le défilement des franges et on procède au comptage de leur nombre durant le temps t que dure le gonflement (environ 40 mn). On peut ainsi mesurer le déplacement libre du miroir et déterminer: la valeur du gonflement exprimé en % ou g/cm3, le gonflement sous contrainte σ (pour comparer avec l'oedomètre) et sa vitesse au cours du temps t.

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