Distributed Systems Robust to Hand Loading Based on Nonresonant Elements

Abstract

The relationship curves of PMF1 dips and PMF2 dips between the wavelength shifts and the temperature which ranged from 20 to 40 C are shown in Figure 5. It is observed that two wavelength dips slide synchronously in same directions and the temperature sensitive coefficients are 20.2530 and 20.2594 nm/ C, respectively. It proves that temperature effect can be neglected.To measure the reversibility of the optical fiber humidity sensor, the humidity sensor was subjected to one cycle of humidity between 20 and 80%. From the results shown in Figure 6, it is observed that the humidity exhibits good reproducibility. The time response of the proposed sensor was also evaluated during the experiment. The response time of the sensor is about 6 sec when the surrounding RH is increased from 20 and 80%. Compared with recently reported humidity sensors [14-16], it is not only fast response time but also high sensitivity. The time response is dependent on a numerous of factors convoluted together, including the water absorption rate, the swelling rate, and the thickness of the coating material that is applied as the sensing element for humidity measurement. The time response of the proposed sensor can be improved by optimizing the coating parameters and thickness. CONCLUSIONA relative humidity sensor based on two PMFs Sagnac interferometer with temperature compensation is presented and demonstrated experimentally. The resonant wavelength dips of the proposed sensor have a red-shifted linearly with the increase of humidity values. The sensitivity of the humidity measurement of about 111.5 pm/%RH is achieved within the humidity range 20-80%RH, whereas the coefficient effected by temperature is only 7.2 pm/ C that the temperature can be totally neglected during the experimental process. Moreover, the sensor structure is very simple and easy to setup and inexpensive, so it shows the great potential for RH sensing applications. ACKNOWLEDGMENTS Relative humidity sensor based on tilted fiber Bragg grating with polyvinyl alcohol coating, IEEE Photonics Technol Lett 21 (2009), 441-443. 5. J.M. Corres, F.J. Arregui, and I.R. Matias, Design of humidity sensors based on tapered optical fibers, J Lightwave Technol 24 (2006), 4329-4336. 6. O. Frazao, B.V. Marques, P. Jorge, J.M. Baptista, and J.L. Santos, High birefringence D-type fiber loop mirror used as refractometer, Sens Actuators B Chem 135 (2008), 108-111. 7. Simultaneous strain and temperature measurement using a highly birefringence fiber loop mirror and a long-period grating written in a photonic crystal fiber, Opt Commun 282 (2009), 4077-4080.

MIMO multiband antenna system with nonresonant elements

“…). It should be note that shows an identical radiating structure however with a completely different architecture. In particular, in the present proposal, those nonresonant elements in charge of the same frequency region are used for MIMO, that is, it is a two port solution (the same applies for the other frequency region).…”

“…In particular, in the present proposal, those nonresonant elements in charge of the same frequency region are used for MIMO, that is, it is a two port solution (the same applies for the other frequency region). However, in it is not a MIMO solution. In particular, those nonresonant elements in charge of a frequency region are connected so as to provide a robust system to hand‐loading.…”

On-frame dual-loop antenna with narrow ground clearance for the 2.4/5.2/5.8-GHz WLAN operation in the smartphone

“…[2]. Designing a dual-band antenna is possible with certain approaches to control the current distribution of one of the higher order resonant modes of the structure, enabling it to change its resonant frequency [3]. Hu et al [4] proposed a dual band reconfigurable antenna but used two external matching circuits.…”

“…Traditionally, the internal antennas for the smartphone are embedded in close proximity to the top or bottom edges of the main circuit board therein. It is also noted that, owing to the recent multiinput multioutput (MIMO) operation requirement for the long-term evolution (LTE) system [1][2][3][4] or the wireless local area network (WLAN) system [5][6][7][8][9][10] to increase the channel capacities [11,12], more internal antennas are needed to be embedded within the very limited space in the smartphone. For example, two LTE antennas for the 2 3 2 LTE MIMO and/or two WLAN antennas for the 2 3 2 WLAN MIMO operation have been deployed in some tablet devices.…”