Autoren: |
D. Nikolai, K.-D. Kammeyer |
Kurzfassung: |
A novel DS-CDMA transmission scheme combining the two well-known techniques of M-ary orthogonal and differential PSK-modulation is presented. This "hybrid" scheme is applicable to the noncoherent uplink of the IS-95 system where up to now only M-ary modulation is used. The additional, PSK-modulated data show a slightly increased bit error rate (BER) compared to the data from M-ary modulation. However, the overall degradation caused hereby is far outweighed by the gain achieved by a higher spreading factor. Analytical results confirmed by simulations yield an improvement of approximately 1.0 dB in terms of Eb/No on a Rayleigh fading channel when no channel coding is used. This considerable gain is achieved upon only slight modification of the conventional modulation/demodulation procedure at a low additional complexity. It will be demonstrated that the IS-95 system is not properly designed since the full exploitation of noncoherent demodulation techniques results in a gain of nearly 2.0 dB. nk97_paper.ps.gz |
Dokumenttyp: |
Konferenzbeitrag |
Veröffentlichung: |
Helsinki, Finland, 1. - 4. September 1997 |
Konferenz: |
IEEE 8th International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC 97) |
Seiten: |
256-260 |
Volume: |
2 |
Index: |
29 |
Dateien: |
BibTEX
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