Effects on portable antennas of the presence of a person

Abstract

strong enhancement of the electric-field values in SC-2 as compared with the ones obtained without the eyeglasses (that is, SC-1). The results obtained from the two scans (corresponding to the left and right eye lines, respectively) are reported in Figure 5. For the right eye (the one closer to the antenna), which is supposed to be positioned about 20 mm from the lens plane, we have measured a field value of 78.3 V/m, corresponding to 2.12 times the value observed without the eyeglasses. The left eye, on the contrary, exhibits a value of 48.4 V/m, which is more than 2.86 times above the value in the absence of eyeglasses. These values are expected to be different from those which can be measured in the real scenario, where the user's head is considered. However, also in this case, we anticipate a field increase in the ocular region, induced by the presence of the eyeglasses with metallic frames. CONCLUSIONThe enhancement induced by metallic eyeglasses on the e.m. field emitted by a cellular telephone has been investigated numerically and experimentally in a simplified scenario, where we neglect any e.m. effect arising from the presence of the user's head tissues. A significant local increase of the electric field has been detected. This can be especially relevant in the eye region, where hazardous situations can be envisaged. ACKNOWLEDGMENTPart of this work has been sponsored by MIUR.

Actual Diversity Performance of a Multiband Diversity Antenna With Hand and Head Effects

“…The obvious gain performance degradation seen in the aforementioned studies agrees well with the results obtained for the single frequency band, single antennas in the proximity of a user [14]. However, the behavior of the envelope correlation as well as the relationship between correlation and MEG, and their impact on the diversity performance is not as consistent.…”

User Effects in Beam-Space MIMO

“…In the case of conventional user terminals, comprehensive studies have been conducted to investigate the user hand and head effects [9]- [13]. In beam-space MIMO, some of the MIMO sub-streams are directly modulated onto the antenna far-field.…”

Location Dependency and Antenna/Body/Sensor-Lead Interaction Effects in a Cell-Phone Based GSM 1800 Telemedicine Link

“…The bodyshadowing effect found when a cellular telephone is held close to the user's head is well known and validated [3], [4] and [5]. However, in a telemedicine application, the handset must operate effectively when body-worn at waist height, a convenient location for fixed use over 24-72 hours -a likely monitoring period -and allow the routing of cables to biomedical signal acquisition modules, as shown in Figure 3.…”