The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper a test method is proposed to assess the performance, characterise, measure and then model the high frequency impedance of simple mechanical ground contacts that are used within mobile phones. A simple test fixture is defined that allows the ground contact attenuation performance between 2 ports to be measured over a wide frequency range. A simulation model for the test fixture and ground...
The temporal and spatial characteristics of lightning activities across Hong Kong, a mountainous metropolis surrounded by sea, has been studied. Over 0.32 million of cloud-to- ground (CG) and intra-cloud (IC) flashes reported by Hong Kong Lightning Location Network during 2005 to 2008 were analyzed. Seasonal variations show that although the lightning activity in summer is the strongest, the ratio...
This paper presents the requirements on the preselect-filter for UWB applications for different Front-End linearities and interference scenarios. A procedure to calculate the minimum out of band attenuation was developed in order to achieve a high system performance in presence of interferer. A filter diagram is proposed for a robust UWB communication. Results show which UWB-bands are affected by...
The conversion of radiated field strength at different distance in semi-anechoic chamber is analyzed. Firstly, the empirical model based on the logarithmic distance path loss is introduced. Secondly, theoretical models of radiation field in the same site or the different site at different distance are obtained through calculating the difference of normalized site attenuation (NSA) with different transmit...
According to CISPR 16-1 & ANSI C 63.4 standard requirements, to implement EMI radiated emission measurement needs to use accuracy antenna factor (AF). The Standard Site Method(SSM) of antenna calibration is most popular technology in the EMI sector. In Taiwan, the SSM calibration technology is also to set up in BSMI WUDA Antenna Site to calibrate broadband antennas (30 MHz to 1 GHz). This paper...
An examination of the electromagnetic environment and characteristics from 30MHz-7GHz in a hospital is discussed in this paper. Empirical propagation constants, building attenuation, floor height gain, and the CDF of the coverage, were calculated from 50-1950MHz. This is carried out to further understand the propagation of radio waves through hospitals. The understanding of wave propagation through...
The International Electrotechnical Commission (IEC) has been working for nearly 20 years preparing standards and other publications dealing with the threat of high-altitude electromagnetic pulse (HEMP) from a high-altitude nuclear detonation and the threat of intentional electromagnetic interference (IEMI) produced by electromagnetic weapons used by criminals or terrorists. In addition to establishing...
We discuss in this paper the propagation of lightning current pulses along conical tall structures. Although the dominant mode of a conical transmission line is TEM, such a structure can also support higher-order TE and TM modes which display a gradual cutoff frequency. Recently, Baba and Rakov's FDTD numerical analysis revealed that for a conical structure, while the current pulses suffer no attenuation...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.