Y. D. Chen

Characteristics of UWB antenna and wave propagation

This paper proposes an omni-directional UWB antenna pattern in azimuth cut, low voltage standing wave ratio (VSWR), and easy to construct antenna for ultra wideband (UWB) systems. The designed antenna uses the multi circular blade configuration with a radiating element and on two different ground planes (square and circular ground shape). The multi-circular blades UWB antenna suitable for IEEE 802.15.3a and IEEE 802.16 UWB communication applications at 3.1-10.6 GHz and 2-11 GHz bands is presented and in specification. This paper discusses the phenomenon of dispersal in UWB antennas and presents a simple design to evaluate the radiated fields from antennas structures. About the characteristics of UWB antenna of antenna bandwidth, antenna efficiency, co-polarization, cross-polarization and pattern integrity are discussed and measured and compared. New multi-blades circular metal for orthographical monopole UWB antenna design and enhanced which measured results exhibit extend return loss bandwidth and lower omni-directional pattern deviation in azimuth cut and lower pattern ripple. The antenna design allows a quick assessment of dispersion in design. The proposed multi-circular blades UWB structures is capable of achieving broadband and omni-direction at azimuth cut characteristics within 2-1 IGHz for UWB wireless communication applications and experiment.

The Compact Yagi Antenna Design Serve Beamforming Operation and Smart Antenna Application

In this paper, a compact and lower profile Yagi-Uda antenna with a balanced to unbalanced (sleeve balun) feed network and directional beam controlled by reflector and directors is presented. Parasitic director, driver and reflector of the designed antenna are designed to control the beam peak and beam bandwidth by the director toward the end-fire direction to centralize radiation power energy for point to point downlink and uplink multi direction multiplexed wireless communication applications and applied 4×4 beamforming (bulter matrix) network for smart antenna design and measurement.

Characteristics of UWB Bands Measurement, Human Effect, and Power Absorption

This paper presents an evaluation of electromagnetic (EM) emission energy by using far-field environmental measurement. The ultra wide-band (UWB) radiator is used due to fit characteristics of new generation communication device. It is applied to approach specific anthropomorphic mannequin (SAM) in order to measure in terms of EM energy, radiation pattern, impedance, and specific absorption rate (SAR), respectively. Scattering and power absorption are also evaluated. Finally, the numerical method FDTD is used to compare experiment results. By using far-field to measure EM radiation energy may be acceptable and worktable.