1-2hit |
Daisuke FUNAHASHI Takahiro ITO Akimasa HIRATA Takahiro IYAMA Teruo ONISHI
This study discusses an area-averaged incident power density to estimate surface temperature elevation from patch antenna arrays with 4 and 9 elements at the frequencies above 10 GHz. We computationally demonstrate that a smaller averaging area (1 cm2) of power density should be considered at the frequency of 30 GHz or higher compared with that at lower frequencies (4 cm2).
Jinkuan WANG Tadashi TAKANO Kojiro HAGINO
The technique for estimating the parameters of multiple waves provides a convenient tool for analysis of multiple wave-fields and eventually for actual applications to mobile communications. Several algorithms have been proposed for those purposes. However, the best tactics to resolve multiple wave-fields are still imperfectly understood at present. This paper proposes a new method for estimating the angles and power levels of arrival waves based on the extended Kalman filter. A space-variable model which we call a spatial state equation is derived using array element locations and incident angles. It has been shown that by means of the model, the estimation of incident waves can be transformed into the problem of parameter identification in linear system which can be carried out by the extended Kalman filter conveniently. The algorithm is initiated directly by the signal received at each array element. The detailed procedure of an extended Kalman filter approach is given in the paper. The performance of the proposed approach is examined by a simulation study with two signals model. The simulation results show a good estimate performance, even in the case that two waves arrive from close directions.