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In this paper we propose the dynamic control of the beamwidth of partially reflective surface (PRS) antennas. Theoretical aspects are presented together with modeling issues. The potential and limitation of the concept are then evaluated. Finally, a detail ...
The dynamic control of the beamwidth of a partially reflective surface (PRS) antenna is reported for the first time. First, a design methodology is proposed by revisiting the PRS antenna theory from the perspective of its reconfigurable beamwidth operation ...
Institute of Electrical and Electronics Engineers2010
Recent advances in nanolithography have allowed shifting of the resonance frequency of antennas into the optical and visible wavelength range with potential applications, for example, in single molecule spectroscopy by fluorescence and directionality enhan ...
In this paper, wearable antennas in close proximity of a human body are considered, focusing on portions of the frequency range between 200 MHz and 2700 MHz. In specific, non-patch type antennas with multi-band operation, light weight, easy integration wit ...
Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2009
Formal research on Ultra-wideband (UWB) technology started in the U.S. in 2002; where its definition was formulated and the frequency allocation in that country established. However, the first ultra-wideband transmission was done during the confirmation of ...
The need of efficient antennas in handheld terminals has increased drastically due to the fast development of wireless services. These antennas should be small, efficient and cover multiple frequency bands. But efficiency in antennas is limited by fundamen ...
Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2009
Three antenna systems, composed of circular monopoles with different ground plane sizes, are studied. The transmission of an UWB pulse between two identical monopoles is analyzed. The omnidirectional properties of the UWB antennas are measured and simulate ...
IEEE Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2009
According to the cognitive radio paradigm, a terminal or subsystem will opportunistically select a frequency band for data transmission. Because the spectrum is shared, a cognitive system may face interference that cannot be given a statistical description ...
Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2008
The paper develops a dynamic antenna scheduling strategy for downlink MIMO communications, where the transmitted signal for each user is beamformed towards a selected subset of receive antennas at this user. The proposed method removes the condition on the ...
