The CFA, as a very compact antenna, much less than the minimum height approved by the FCC, has solved the problems of huge size and heights of conventional antennas, which are related to the wavelength (Lamda/2 mast antenna) which reaches hundreds of meters. , associated with high voltages and very large earthing copper net, which needs hundreds of acres of land, adding to high enormous extending near field and fading problems and interference with neighbor stations , so reducing their power at night time or completely shut down.
BUT the CFA has very little plate voltage, with no extending induction field or sky waves., and 24 hours service at full power , because no interference with other stations at night time .
The near field of the CFA is 1/ R dependence, i.e. the near field is directly proportional to distance, which is a very important unique fact of the CFA, confirming the near field radiation.
Briefly the CFA Characteristics are:
CFA Theory :
The CFA is a model for the far field radiation of the master high antenna. The twin feeder Crossed Field Antenna is a near field radiator, working by splitting the transmitter power into two equal powers (through a phasing unit) into the plates of the CFA antenna. The CFA plates generating separately electric field E and magnetic field H , in time phase , whose ratio E/H matching space impedance , so radiation starts from the near field to free space to infinity .
The input impedance of the CFA is pure resistance adjustable to any value ( normally 50 Ohms ) , with zero reactance which means no stored energy in the near field , only radiating field , with zero induction field ,as very low Q antenna .The CFA is a very low profile antenna. The CFA was fed with 10 Kw DRM power (very broad bandwidth).
The near field of the CFA is 1/ R dependence, i.e. the near field is directly proportional to distance, which is a very important unique fact of the CFA, confirming the near field radiation., i.e confirming Synthesizing the Poynting Vectors from the near field of the CFA .
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