| 摘要 |
433,842. Wireless signalling. MARCONI'S WIRELESS TELEGRAPH CO., Ltd., Electra House, Victoria Embankment, London. (Assignees of Wolff, 1.; 41, West Walnut Avenue, Merchantville, and Linder, E. G.; 306, Cooper Street, Camden, both in New Jersey, U.S.A.) Dec. 24, 1934, No. 36980. Convention date, Dec. 23, 1933. [Classes 39 (i) and 40 (v)] Signals are transmitted, preferably on microwaves, by using a body of ionized gas situated in a magnetic field to vary the plane of polarization of the emitted wave. As shown in Fig. 2 the wave is emitted by a dipole aerial 3 at the focus of a reflector 7. The wave passes through a tube 9 containing ionized gas, such as neon, and the signal varies the gas ionization and so rotates the plane of polarization of the wave. The tube 9 is surrounded by a coil 47 connected to a D.C. source 49, and by a second coil 51 which is traversed by a high-frequency current from the source 53 modulated by the signal from the microphone 25. The signal may be received by using a dipole receiving aerial set at a suitable angle so as to give a response which varies with the varying plane of polarization of the arriving wave. As shown in Fig. 2, however, the wave passes through an analysing grating 58, which converts the wave into an amplitude-modulated wave. The receiver may then be equally responsive for all planes of polarization, and may comprise a neon tube 61 at the focus of a reflector 33, and with its electrodes connected to a receiver 35<1>. Alternatively two receiving dipoles at right angles to each other may be arranged for independent reception, and may feed the same receiving telephone. In another form of modulating tube, an axial cathode and a cylindrical anode are connected by a D.C. source. The microphone is connected through a transformer to a coil surrounding the tube. In a further form shown in Fig. 3, a series of long helical tubes 73 of different diameter are arranged one within another. The tube electrodes 75 are connected in parallel to a D.C. source 15 ; and a coil 17 surrounding the outer helix is energized by the microphone 25 through a transformer 23. |
