| 摘要 |
553,636. Wireless receiving and transmitting circuits. PHILIPS LAMPS, Ltd. (Naamlooze Vennootschap Philips' Gloeilampenfabrieken). Nov. 26, 1941, No. 15247. [Class 40 (v)] A circuit for coupling a dipole antenna 4 to a transmission line connected to terminals 1, 2, with or without a transformer 8, so as to ensure correct matching over a wide frequency band, comprises a resistance in two parts 5, 6 which together equal the radiation resistance of the antenna, tapped on to a resonant circuit 7 tuned to the natural frequency of the antenna 4. The tappings are chosen so as to include an inductance which is equal to the capacity of the antenna multiplied by the square of the radiation resistance. With these conditions the arrangement presents at the terminals 1, 2 an impedance which is a pure resistance equal to the radiation resistance of the antenna over a wide band of frequencies. |
