| 摘要 |
Apparatus is provided to allow the reception and/or transmission of data signals at two different frequency bands. The apparatus includes a waveguide which has a first section of larger cross sectional area for receiving and/or transmitting the lower frequency band signals, and a reducing section which leads to a section with a reduced cross sectional area in comparison to the first section and this allows the receipt of the higher frequency band signals. In one embodiment sections of the waveguide can be rotated to allow the apparatus to be adjusted to any particular orientation to suit the particular circular polarity transmission type at the location at which the apparatus is provided at that time. |
