Combined coding and spreading in CDMA systems using maximum free distance convolutional codes
Paper i proceeding, 1998

In CDMA systems maximum theoretical performance can be obtained by spreading with low-rate error control codes. Previously, orthogonal and superorthogonal codes have been proposed for this purpose. We present a family of rate-compatible low-rate convolutional codes with maximum free distance. The performance of these codes for spectrum spreading in a CDMA system is evaluated and shown to outperform that of orthogonal and superorthogonal codes as well as conventional coding/spreading schemes. We also show that our low-rate codes will give simple encoder and decoder implementation. With these codes any 1/n rate can be obtained regardless of the constraint length, resulting in a more flexible and powerful scheme than those proposed up to now.

maximum free distance

low-rate convolutional codes

orthogonal codes

superorthogonal codes

rate-compatible

CDMA

Författare

Pål Frenger

Chalmers, Signaler och system, Kommunikations- och antennsystem, Kommunikationssystem

Pål Orten

Chalmers, Signaler och system, Kommunikations- och antennsystem, Kommunikationssystem

Tony Ottosson Gadd

Chalmers, Signaler och system, Kommunikations- och antennsystem, Kommunikationssystem

Proceedings IEEE Vehicular Technology Conference, Ottawa, Canada

Vol. 3 2497-2501

Ämneskategorier

Data- och informationsvetenskap

DOI

10.1109/VETEC.1998.686209

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Skapat

2017-10-06