By Melanie M Daniels

Power modules, as discussed in ihis article, are the output stage of the RF (radio frequency) amplification chain in a mobile telephone (Fig. 1). Some telephones use integrated circuits as power solutions, but for output power greater t han one watt a discrete device is usually used. A power module uses networks to match the discrete stages in a hybrid amplifier. This article describes a power module designed for a GSM (Global System for Mobile Communications) handheld telephone. GSM telephones...

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Fig. 2,T -n LC models fora coaxial cable. The five-segment model is accurate over a wider range of frequencies than the one-segment model. Fig. 2,T -n LC models fora coaxial cable. The five-segment model is accurate over a wider range of frequencies than the one-segment model. One-Segment - Five-Segment Transmission Mode - Mode --j tine-i One-Segment - Five-Segment Transmission Mode - Mode --j tine-i Fig, 3. fa) Magnitude uf the input Impedance Z n for the transmission line and modeis of Fig....

Tools Utilities and Environment

This section describes the tools selected for the test suite, the utilities created to augment the tools, and the structure oflhe test implementation and operating environment. The Synlib API was one of the most important tools used in the development of the test suite. Synlib is a C-langtiage interface that ptovides a means to simulate progranunatically the actions of a user with a GUI. It also contains features that allow the test program to monitor the state of the desktop. such as watching...

Measuring Parasitic Capacitance and Inductance Using TDR

Time-domain refiectometry TDR is commonly used as a convenient method of determining the characteristic impedance of a transmission line or quantifying reflections caused by discontinuities along or at the termination of a transmission line. TDR can also be used to measure quantities such as the input capacitance of a voltage probe, the inductance of a jumper wire, the end-to-end capacitance of a resistor, or the effective loading of a PCI card. Element values can be calculated directly from...

Accessing and Administering Applications in CDE

Setting up transparent access to applications and resources in a highly networked environment is made simpler by facilities that enable system administrators to integrate applications into the CDE desktop. by Aji it a Ellendman and William R. Voder A nuyor purpose of a graphical desktop is to make it easier for users to browse and run applications and to identify and manipulate the applications' data files. Since UNIX4 systems are generally highly networked, it is desirable that a desktop also...

Platform Independence

Synlib programs can be written so that they are completely platform independent For example, in the program above there is nothing that is tied to spec ilk- features of a platform or a display on which the target GUI application may be executing. All platform dependent information can be and is encouraged to be abstracted away through ihe mechanism of snjl coding. In the program above, the statement using the function SynClickButtor is an example of soft coding. The last parameter in t lus...