| 摘要 |
A satellite communication system includes first, second and third electromagnetic radiators, the first and second of which are a contiguous pair, and the second and third of which are also contiguous. Two channels of information are each modulated onto carriers at the same frequency by means of mutually independent modulations. The modulations may be by orthogonal pseudorandom codes. The first channel is applied to the first and second radiators, and the second channel is applied to the second and third radiators. The first and second radiators form a beam which if decoded for the first modulation is independent to that formed by the second and third radiators. Consequently, the feed apertures overlap in a manner which provides a more constant field intensity in each beam, and which saves size and weight by comparison with a single radiator of corresponding aperture for each channel. In order to avoid the need for linear amplifiers and to reduce power consumption needs attributable to the overlapping apertures, the carriers are phased in mutual quadrature. |
