ASSGNMENT 1
TRANSMISSION LINE CIRCUIT REPRESENTATION DIAGRAM AND THE ROLE OF RF CIRCUIT IN RADIO TELEVISION TRANSMITTER
RF covers a range of high-frequency, electromagnetic frequencies used for radio transmissions. In communications, RF signals transmit data using various methods, such as TDMA, CDMA, DSSS (direct-sequence spread spectrum), and others. ...www.intel.com/products/glossary/body.htm
(RF) - frequencies of electromagnetic waves between approximately 3 kHz (3,000 Hz) and 300 GHz (3 x 10 11 Hz). Sometimes, a distinction is drawn between radio waves, which have frequencies between 3 kHz and 1 GHz, and microwaves, which have a frequency between 1 GHz and 300 GHz.......cellphonesafety.wordpress.com/glossary
Radio frequency, or RF, is a frequency or rate of oscillation within the range of about 3 Hz and 300 GHz. This range corresponds to frequency of alternating current electrical signals used to produce and detect radio waves. Since most of this range is beyond the vibration rate that most mechanical systems can respond to, RF usually refers to oscillations in electrical circuits.
Special properties of RF electrical signals
Electrical currents that oscillate at RF have special properties not shared by direct current signals. One such property is the ease with which it can ionize air to create a conductive path through air. This property is exploited by 'high frequency' units used in electric arc welding. Another special property is an electromagnetic force that drives the RF current to the surface of conductors, known as the skin effect. Another property is the ability to appear to flow through paths that contain insulating material, like the dielectric insulator of a capacitor. The degree of effect of these properties depend on the frequency of the signals.
Special properties of RF electrical signals
Electrical currents that oscillate at RF have special properties not shared by direct current signals. One such property is the ease with which it can ionize air to create a conductive path through air. This property is exploited by 'high frequency' units used in electric arc welding. Another special property is an electromagnetic force that drives the RF current to the surface of conductors, known as the skin effect. Another property is the ability to appear to flow through paths that contain insulating material, like the dielectric insulator of a capacitor. The degree of effect of these properties depend on the frequency of the signals.
transmission line circuit representationASSGNMENT 2
WHAT IS THE IMPORTANCE OF THE SMITH CHART IN RF SYSTEM
The Smith Chart, invented by Phillip H. Smith (1905-1987),[1][2] is a graphical aid or nomogram designed for electrical and electronics engineers specializing in radio frequency (RF) engineering to assist in solving problems with transmission lines and matching circuits.[3] Use of the Smith Chart utility has grown steadily over the years and it is still widely used today, not only as a problem solving aid, but as a graphical demonstrator of how many RF parameters behave at one or more frequencies, an alternative to using tabular information. The Smith Chart can be used to represent many parameters including impedances, admittances, reflection coefficients, scattering parameters, noise figure circles, constant gain contours and regions for unconditional stability.The Smith Chart is most frequently used at or within the unity radius region. However, the remainder is still mathematically relevant, being used, for example, in oscillator design and stability analysis.....
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