| 摘要 |
970,457. Waveguides. TELEFUNKEN PATENTVERWERTUNGS G.m.b.H. Feb. 21, 1963 [Feb. 23, 1962], No. 6956/63. Heading H1W. A waveguide for the transmission of H 10 mode energy has an approximately rectangular cross-section with slots formed in at least one narrow wall and at least one broad wall bulged or curved outwardly. As shown, both broad walls are outwardly bulged and, in addition to transverse slots 3 in the narrow wall (or walls) a series of short longitudinal slots 2 are provided along the centre line of the board wall (or walls). In addition, one or both of the narrow walls may be curved inwardly, e.g. as shown in the modified cross-section of Fig. 3. The slots prevent the formation of spurious modes associated with longitudinal wall currents. The energy associated with the undesired modes may be radiated from the slots and may be absorbed in dissipative auxiliary waveguides adjacent the main waveguide. The bulging of the waveguide removes the equality of the phase velocities and cut-off frequencies of the E 11 and H 11 modes whereby generation of so-called " longitudinal sectional waves " is prevented. For a given working frequency, the waveguides of the invention are made larger than standard waveguides. |
