Measuring of the reflection coefficients close to 1 with the help of a quasi-optical reflectometer,based on hollow metal-dielectric waveguides

This paper considers the measurement technique features of large reflection coefficients at millimeter wavelengths and structure and design parameters of the measuring bench, containing a quasi-optical reflectometer, built on the basis of hollow rectangular metal-dielectric waveguides. Measurement results of the reflection coefficients of planar samples with reflection coefficient close to 1 (metallized films, fine-period metal grids) are presented. The results may be of interest in the development of foldable antennas and devices for controlling the backscattering of electromagnetic waves from the objects of complicated geometrical form.     

A reliable and manufacturable method to induce a stress of >1 GPa on a P-channel MOSFET in high volume manufacturing

This letter discusses a reliable and manufacturable integration technique to induce greater than 1 GPa of stress into a p-channel MOSFET, which will be required to increase the drive current beyond 1 mA//spl mu/m at the sub-90-nm process generation. Uniaxial compressive stress is introduced into the p-channel by both a selective deposition of SiGe in the source/drain and an engineered 2.5-GPa compressively stressed nitride. The highest to date compressively stressed SiN film is obtained by heavy ion bombardment during the deposition of the film.     

A UTD/FDTD investigation on procedures to assess compliance of cellular base-station antennas with human-exposure limits in a realistic urban environment

In this paper, different exposure situations for a subject standing inside a room of a building with a window facing a rooftop-mounted base-station antenna are analyzed. The study is accomplished by using a technique combining the uniform asymptotic theory of diffraction and the finite-difference time-domain method, suitable to characterize human exposure in realistic urban environments at a reasonable computational cost. The different exposure conditions examined are analyzed to highlight the problems related to compliance assessment procedures in complex exposure scenarios and to suggest some possible solutions. A comparison of the results obtained in these scenarios with those computed neglecting the presence of the room walls (free-space situations) evidences that, under certain conditions, average exposure field levels and specific absorption rates (SARs) in the realistic environments can be higher than in free space, thus demonstrating that compliance assessment carried out in free space can yield nonconservative results. As concerns implications of field nonuniformities, typical of realistic urban environments, on SAR values, the results show that the whole-body averaged SAR is related to the average field value, provided the averaging procedure is appropriately chosen to cover all the volume occupied by the subject (V/sub S/) and not only a vertical surface. Local SAR values, instead, show a more complex relation with the exposure field, such that considering only the V/sub S/-averaged field value for compliance assessment might lead to an underestimation of the real exposure level, while using the peak of the field in V/sub S/ leads to a remarkable overestimation.     

与时俱进加速发展努力开创广播电视标准化工作的新局面--张海涛副局长在全国广播电视标准化技术委员会年会上的讲话

各位委员、同志们:全国广播电视标准化技术委员会2002年年会今天召开了,我代表广电总局表示祝贺!这次会议是在全党和全国人民深入学习、贯彻落实党的十六大精神的重要时刻召开的.