Smart Antenna using Switched Multibeam Array Ms
This paper describes the design and realization of a 44 Butler Matrix as a beam forming network along with 4 linear antenna arrays to obtain four steerable beams, operating at 2.4 GHz. The simulation results are obtained using HFSS software. Further the concept of multibeam switching is discussed with an idea of suspended feed in between two matrices.
The study of Butler matrix BFN for four beams antenna system
In this paper, four beam patterns with frequency range from 1.7 GHz/spl sim/2.2 GHz is generated by a 4/spl times/2 antenna array. The directions of these beam patterns are /spl plusmn/12/spl deg/ /spl plusmn/40/spl deg/. The antenna directivity changes from 18 dBi to 18.7 dBi for these beam patterns. And the antenna gain changes from 10 dBi to 12.3 dBi. The H-plane 3 dB beamwidth changes from 21 degrees to 24.4 degrees. The test results are quite in agreement with that of simulation.
Numerical Simulation for Natural State of Two-Phase Liquid Dominated Geothermal Reservoir with Steam Cap Underlying Brine Reservoir
Hydrothermal reservoir which liquid-dominated hydrothermal reservoir is a type of geothermal reservoir that most widely used for power plant. The exploitation of mass and heat from the geothermal fluid will decrease the pressure in the reservoir over time. Therefore the pressure drop in the reservoir will have an impact on the formation of boiling zones or boiling will increase. The impacts are an increase in the fraction of steam, dryness, in the reservoir and with good vertical permeability will form a steam cap underlying the brine reservoir. The two- phase liquid dominated reservoir is sensitive to the porosity and difficult to assign average properties of the entire reservoir when there is boiling zone in some area of the reservoir. These paper showed successful development of two-phase liquid dominated geothermal reservoir and discussed the formation of steam cap above brine reservoir through numerical simulation for state natural conditions. The natural state modeling in steam cap shows a match with the conceptual model of the vapor-dominated developed. These paper also proofed the presence of transition zone, boiling zone, between steam cap and brine reservoir.