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The idea of making use of the metal zipper on the handbag to serve as an off-body antenna is proposed, and the simulations together with measurements have been carried out. The feeding point can be located at the bottom of the zipper, and to be more specific, around one of the teeth. The excitation at certain tooth of the zipper would bring variations in the reflection coefficients as well as the radiation patterns. No matter the zipper is totally closed, quarterly opened, half opened, or is even totally opened, the antenna can operate with acceptable performance, though the common status of the handbag zipper is closed. Thus, it is to some extent reconfigurable, especially for radiation patterns. A fractional bandwidth of 4.92% at 2.44 GHz of the industrial, scientific, and medical band with a gain of about 5 dBi has been achieved. The impact of the human body has been evaluated. It is noticeable but affordable. The measured results indicate reasonable agreements to that of the simulations in both the matching performance and the radiation feature for the zipper antenna, which seems to be a promising candidate for body-centric wireless communications and the Internet of Things. [ABSTRACT FROM PUBLISHER]

A shoelace antenna for the application of collision avoidance for the blind person is proposed for the first time. A thin flexible metal wire is used to fabricate the antenna, which can run along with the shoelace without destroying the shoe or adding extra big structures. According to the investigations, to put the feeding probe at the bottom of the cross point is better than the locations around the string bowknot. To make the shoelace tighter or looser will influence the performance with an affordable variation. The effect of the biological tissues has been taken into account during the performance evaluation of the antenna. The measured fractional bandwidth is 11% with a resonance of 2.43 GHz in the ISM Band. The main lobe of the antenna points to the upper front direction with an angle of about 20°, which is suitable for the detecting of the anterior obstacles when walking. The measured results indicate reasonable performance for the shoelace antenna to serve as a tool for the blind person. [ABSTRACT FROM AUTHOR]

It has been shown that the correlation between the radiation patterns of two antennas can be measured in a reverberation chamber (RC). In this paper, it is shown that the self-correlation coefficient of an antenna, defined as the correlation between the radiation pattern of an antenna under test (AUT) and a transformed version of itself, can also be measured in an RC. It is found that the 3-D radiation pattern of the AUT can be reconstructed from the measured self-correlation coefficient by using spherical wave decomposition. Moreover, the axial ratio of the AUT can also be measured efficiently in the RC, when the pattern is directional. Numerical simulations and measurements in the RC and in an anechoic chamber have been undertaken. Good agreement is obtained, which confirms the validity of the proposed method. Thus, this novel method can become a very useful, cost-effective, and efficient method for 3-D antenna radiation pattern measurement. [ABSTRACT FROM PUBLISHER]

One of the most important applications of a reverberation chamber is for radiated power measurement. Two new alternative methods are proposed to measure the radiated power of equipment under test in a reverberation chamber in this paper. Traditionally, as stated in IEC 61000-4-21 standard, this measurement requires two antennas, a signal generator and a spectrum analyzer or receiver. However, it is found that if a signal generator is not available, a vector network analyzer can be used to complete the measurement. Furthermore, if only one antenna is available, by taking advantage of the enhanced backscattering effect, the measurement can still be completed. By incorporating the one- and/or two-antenna methods, the radiation efficiency of antennas is also considered. Measurements have been conducted to verify the proposed methods, the results from these three methods are compared, and a very good agreement is obtained. It is found that the two proposed methods are simpler than the conventional method. [ABSTRACT FROM AUTHOR]

A cylindrical spiral liquid antenna and a tapered helical water antenna are presented. Saline water with a concentration of 3.5% is injected into a flexible tube to form the radiation structure. Thresholds for changes of the radiation direction are calculated to be 0.1 and 0.4 for the ratio between the spiral diameter and the wavelength. Resonance frequency increases when the probe length or the radius of the vertical liquid decreases. The quantity of the water could be changed with the help of a syringe to enable the reconfigurability. Measurement results show fairly good agreements with that simulated. [ABSTRACT FROM AUTHOR]