| 摘要 |
PURPOSE:To attain multiband applications of an antenna and to radiate electromagnetic waves in an arbitrary frequency except the resonance frequency, by switching a PIN diode with a bias circuit and changing over the length of an antenna line. CONSTITUTION:The PIN diode 6, without a forward bias current to it, acts like a capacitor of a minute capacitance value and shows the state the same as a switch being turned off. In applying the forward bias current to the diode, it shows a minute high frequency resistance and a high frequency current can be conducted from both anode and cathode of it like the switch to be turned on. Thus, the high frequency current, F1, F2 in frequency in radiated in air as electromagnetic waves from one antenna by switching on/off the forward bias current to the PIN diode 6. |
