Topic
Active antenna
About: Active antenna is a research topic. Over the lifetime, 2246 publications have been published within this topic receiving 26493 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: Numerical results demonstrate that under high Doppler spread and large handoff-delay conditions, the proposed soft-handoff employing two transmit antennas and the optimum handoff threshold achieves a significant gain in microcell environments, but not in macrocell environments.
Abstract: We consider forward-link soft-handoff with multiple antenna selection and fast joint power control at high data rates in a cellular code-division multiple-access network, where signals are directed to a mobile station (MS) from antennas located at the same or different base stations. The total power transmitted to any mobile is divided among the active antennas selected according to the momentary channel conditions so as to maximize the signal-interference ratio at each MS. Multiple-antenna selection is used to mitigate the effects of both short- and long-term fading, and achieve the best soft-handoff with respect to system capacity and complexity. To achieve capacity gains with soft-handoff, we derive optimum handoff thresholds corresponding to the optimum handoff region in different cell environments. Numerical results demonstrate that under high Doppler spread and large handoff-delay conditions, the proposed soft-handoff employing two transmit antennas and the optimum handoff threshold achieves a significant gain in microcell environments, but not in macrocell environments.
10 citations
01 Jan 1999
TL;DR: In this article, a new structure for a slot loop antenna fabricated on a high resistivity P-type (10 kΩcm) silicon wafer is presented, which effectively reduces the effective dielectric constant of the substrate and enhances radiation efficiency.
Abstract: A new structure for a slot loop antenna fabricated on a high resistivity P-type(10 kΩcm) silicon wafer is presented in this paper. Wet etched micromachined trenches with conductor hangovers form the slot loop. This method effectively reduces the effective dielectric constant of the substrate and enhances radiation efficiency. The processing methods used and the extension of the antenna configured as a self-oscillating active antenna will be discussed.
10 citations
01 Aug 2014
TL;DR: In this paper, a 3-axis weighted-polarization active antenna is proposed to realize ultra high-speed and high-capacity mobile communications, which is comprised of three orthogonal antennas, two of which can be selected according to a weight function in different situations.
Abstract: This paper presents a 3-axis weighted-polarization active antenna in order to realize ultra high-speed and high-capacity mobile communications. The proposed antenna is comprised of three orthogonal antennas, two of which can be selected according to a weight function in different situations. The weight function is created based on the variation of cross polarization power ratio (XPR) and the inclination angle of an antenna depending on the propagation environment and the human motion. The result shows that a high level of the channel capacity can be obtained even when the variation of XPR and the antenna inclination angle are taken into consideration simultaneously, demonstrating that gigabit high-speed communication can be realized using the proposed antenna.
10 citations
TL;DR: In this article, a new design for an active antenna in which an FET oscillator is integrated with a notch antenna has been demonstrated, which is suitable for use as a low cost transmitter or in quasi-optical power combining arrays.
Abstract: A new design for an active antenna in which an FET oscillator is integrated with a notch antenna has been demonstrated The structure radiates 89mW of power at a frequency of 698GHz The FET active notch antenna is suitable for use as a low cost transmitter or in quasioptical power combining arrays
10 citations
08 Jun 1997
TL;DR: In this article, a three-dimensional active antenna configuration for a front-end module of a high-speed wireless communication system at millimeter and quasi-millimeter-wave frequencies is proposed.
Abstract: This paper proposes a three-dimensional active antenna configuration for a front-end module of a high-speed wireless communication system at millimeter and quasi-millimeter-wave frequencies. The active antenna is integrated with a microstrip antenna array on multilayer alumina-ceramic, individual MMIC chips including transmit/receive amplifiers, time division duplex switches, and a filter on multilayer polyimide. The three-dimensional structure achieves an unrestricted RF-circuit design on multilayer polyimide.
10 citations