CDMA truy cập và chuyển mạch P6

The Spectrally Efficient CDMA Performance Overview As we have discussed in Chapter 3, the SS/CDMA Traffic channels are based on a spectrally efficient CDMA (SE-CDMA). The SE-CDMA is designed to reuse each frequency channel in every satellite beam (frequency reuse one), and also achieve a very low bit error rate (10−6 to 10−10 ) at a very low signal-to-noise ratio (Eb /No ). The low Eb /No value will allow the use of an Ultra Small Aperture Terminal (USAT) (antenna dish 26” in diameter), and provide a sufficient margin to mitigate the Output Back-Off (OBO) at the on-board downlink power...