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Owing to their inherent isolation and ability for remote interrogation, wireless sensors are an effective way to monitor the operation of high-voltage power transmission lines. A wireless sensor on a high-voltage line has the potential to form corona discharges, particularly on an exposed antenna. The effects of corona formation on the antenna of a wireless radio frequency (RF) communication system were studied. The physics of corona plasma formation and charge composition was analyzed, leading to a theoretical understanding of corona interaction with the antenna. Through a series of high-voltage experiments, the effects of corona on the impedance and gain of an antenna, as well as the RF interference generated by corona current pulses, were identified. RF interference and low-frequency corona current were observed to have the largest impact on a wireless RF system. Corona was found to have no significant impact on the impedance or gain of an antenna. Based on the results, design guidelines were proposed for an antenna and RF front end to be used in wireless high-voltage sensing applications.

With the rapid adoption and development of new standards, Multiple-Input Multiple-Output (MIMO) technology is becoming a necessity in current wireless systems. One problem posed by using multiple antennas at a transmitter or receiver is the undesirable effect of signal correlation between closely-spaced radiating elements. This thesis presents the concept, design, and evaluation of a hemispherical lens antenna for use in MIMO systems. A high-permittivity dielectric material allows radiating elements to be placed in close proximity with reduced spatial correlation effects. An intermediate matching layer and a hemispherical lens design facilitate the preservation of the pattern characteristics in the transition between the dielectric and free-space. The antenna was simulated against benchmark antenna arrays in free-space and showed a 35%-70% improvement in channel capacity in multipath-rich environments, showing strength as a candidate for further development in MIMO applications.

No description available.

No description available.

No description available.

With the rapid adoption and development of new standards, Multiple-Input Multiple-Output (MIMO) technology is becoming a necessity in current wireless systems. One problem posed by using multiple antennas at a transmitter or receiver is the undesirable effect of signal correlation between closely-spaced radiating elements. This thesis presents the concept, design, and evaluation of a hemispherical lens antenna for use in MIMO systems. A high-permittivity dielectric material allows radiating elements to be placed in close proximity with reduced spatial correlation effects. An intermediate matching layer and a hemispherical lens design facilitate the preservation of the pattern characteristics in the transition between the dielectric and free-space. The antenna was simulated against benchmark antenna arrays in free-space and showed a 35%-70% improvement in channel capacity in multipath-rich environments, showing strength as a candidate for further development in MIMO applications.

No description available.

No description available.