Principle, control theory, and application of the ESPAR (Electrically Steerable Parasitic Array Radiator) antenna are introduced. A typical ESPAR antenna consists of monopole or dipole elements, one of which is the radiator (fed element) and the others are the parasitic radiators with variable reactance devices loaded on them. It can provide a lower-cost solution as an adaptive array antenna or...

The problem of the rigid-piston radiator mounted in an infinite baffle has been studied widely for tutorial as well as for practical reasons. The resulting theory is commonly applied to model a loudspeaker in the audio-frequency range. A special function, the Struve function H1 (z), occurs in the expressions for the rigid-piston radiator. This Struve function is not readily available in program...

A printed monopole antenna with CPW-fed is proposed. The proposed antenna includes a rectangle shape radiator, two ground planes with symmetrical notch and feed excitation. It covers the all ultra wideband (UWB 3.1GHz ~ 10.6GHz) and has 7.8GHz (2.8GHz ~ 10.6GHz) measured return loss bandwidth. In modifiable design, we choose to design the notches on the ground plane, the high of the proposed an...

In the present paper, the effect of water-CuO nanofluid on the radiator heat transfer of an automobile, Peugeot 405 XU7 engine type is investigated experimentally. The experiments are carried out for the radiator water (water-ethylene glycol with a volume fraction of 80-20, respectively) as a base fluid and water-CuO nanofluid with the volume fraction of 0.5% and 1%. Sodium Dodecyl Sulfate (SDS...

GLOSSARY OF SYMBOLS r distance from pressure sample point to center of piston a radius of circular radiator R_ dc resistance of driver voice coil ao radius of diaphragm, = _/SD/_r E surface area ay radius of circular vent, = 5/Sv/_r SD effective projected surface area of driver diaphragm c velocity of sound in air, = 343 m/s Sv cross-sectional area of vent ein voltage applied to driver input SP...

Abstract Precise orbit determination of GNSS (Global Navigation Satellite System) satellites requires accurate models perturbing forces acting on the spacecraft, i.e., solar radiation pressure (SRP) and thermal forces. With officially published satellite metadata, analytical box-wing model is usually used to describe most SRP accelerations rest assumed be compensated by estimating ECOM/ECOM2 (E...

This work presents advances on the development of a resonant radiator, obtained as augmentation conventional Impulse Radiating Antenna (IRA) with Frequency Selective Surface (FSS), in L-band. An improved passband-type FSS is by exploring Multiple Split Ring Resonators (MCSRR) unit cells to obtain higher Q-factor radiator. The effects multiband and tunable FSS’s are also studied verified via sim...

An impro ved magnetic-lens spectrometer , similar in principle to tha t described by D eutsch, Elliott, and Evans 1 has been cOllsi,ru cted. The struc t ure, operation, and method of calibrat ion, using a ThB + C deposit, is d escrib ed. R es ults of m easurem ents of t he primary beta-ray specti'um of COHO a nd of t he gamma-ray spect; um converted in a uran ium radiator a rc gi ven. These g i...