![]() ![]() ![]() This site is like a library, Use search box in the widget to get ebook that you want. Click Download or Read Online button to get Antennas And Radiowave Propagation book now. An external tuning network (an antenna tuner) can be used to cancel the reactance and also transform the resistance to a value that matches a receiver's input impedance or to a value that draws a desired amount of power from a transmitter.Home › eBooks Download › antennas and radiowave propagation Antennas And Radiowave Propagationĭownload Antennas And Radiowave Propagation PDF/ePub or read online books in Mobi eBooks. If the reactance is zero at the operating frequency the antenna is said to be resonant, just as an RLC circuit is purely resistive at its resonant frequency. ![]() The impedance will also generally have a nonzero imaginary part, a reactance. If the antenna is efficient, most of the power flows away from the antenna in the form of (energy-bearing) electromagnetic waves and only a small fraction of the power will be dissipated by ohmic heating of the antenna itself. The impedance of the antenna therefore has a real part, a resistance, and draws power from the source. When an ac source (transmitter) is connected to an antenna (practically any metal structure) the resulting current has a component that is in phase with the applied voltage. Here we will consider the transmission through this propagation link. To be more exact, it was sufficient to know that everything between the terminals of the two antennas is equivalent to a linear two-port network. It sufficed to know only that a voltage applied to the terminals of a transmitting antenna causes a proportional voltage to appear very shortly thereafter at the terminals of a receiving antenna. While discussing transmitter and receiver circuitry we did not have to know much about antennas or propagation. ![]()
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