1. Field of the Invention.
The present invention relates generally to a satellite receiver antenna, and in particular, to the aggregated distribution of multiple satellite transponder signals in a satellite dish antenna.
2. Description of the Related Art.
DIRECTV(copyright) can broadcast video programming signals from transponders on three satellites in three different orbital slots located at 101 West Longitude (WL), 119 WL, and 110 WL, also known as Sat A, Sat B, and Sat C, respectively. The FCC (Federal Communications Commission) has allocated to DIRECTV(copyright) transponders 1-32 on 101 WL, transponders 22-32 on 119 WL, and transponders 28, 30, 32 on 110 WL.
In the prior art, a four-input multi-switch (Multi-SW) was used to select among the signals received from the transponders on 101 WL and 119 WL, wherein there are two different signal polarizations (Left and Right) output by each associated low noise block down converters with feed (LNBFs) for each orbital slot and each of the different signal polarizations is a separate input to the multi-switch. However, to accommodate the additional orbital slot located at 110 WL would require a greater number of inputs on the multi-switch.
In a conventional signal acquisition and distribution method, five cables would be used to receive signals from the transponders in the three orbital slots using three associated LNBFs, wherein two of the LNBFs have dual outputs to the multi-switch (one for each of the two signal polarizations for 101 WL and 119 WL) and one of the LNBFs has a single output to the multi-switch (one for the single signal polarization for 110 WL). Further, a conventional signal acquisition and distribution method would require the use of an addressing-capable multi-switch and an integrated receiver-decoder (IRD) capable of providing a compatible addressing signal to the multi-switch to select and decode the five different inputs. This adds a level of complexity to these two devices, increases their manufacturing and installation costs, and lowers system reliability.
Thus, there is a need in the art for a method wherein signals from multiple satellites can be received and distributed using fewer sets of cables. There is also a need for a method that simplifies polarization switching requirements for the LNBFs and IRD.
The present invention describes an antenna or Out Door Unit (ODU) that provides the capability to aggregate signals received from more than one satellite before providing the signals to a multi-switch for selection by an integrated decoder-receiver (IRD). The signals from a first satellite are relocated by means of a local oscillator and multiplier to frequencies of unused channels in the signals from a second satellite. The relocated signals from the first satellite are then summed with the unused channels in the signals from the second satellite.