| 摘要 |
It is now becoming increasingly desirable for set top boxes to be fitted with two or more tuners, each having an associated receiver/decoder. This is to allow, for example, a user to watch a satellite television program whilst recording, on a video recorder, a different satellite television channel. However, since a single LNB can only supply signals from either a vertically or horizontally polarised signal, it is not possible to use a single LNB to provide all the desired portions of the incoming satellite signal. In order to overcome this problem the received satellite signal is separated into portions of interest which portions are combined onto a single output signal. Each portion of interest may be, for example a desired individual frequency having a specific polarization, or may be a frequency band containing a desired individual frequency having a specific polarization. |
