CPL - Chalmers Publication Library
| Utbildning | Forskning | Styrkeområden | Om Chalmers | In English In English Ej inloggad.

Code-spread CDMA using low-rate convolutional codes

Pål Frenger (Institutionen för signaler och system, Kommunikationssystem) ; Pål Orten (Institutionen för signaler och system, Kommunikationssystem) ; Tony Ottosson (Institutionen för signaler och system, Kommunikationssystem)
Proceedings IEEE International Symposium on Spread Spectrum Techniques and Applications, Sun City, South Africa Vol. 48 (1998), 1, p. 374-378.
[Konferensbidrag, refereegranskat]

In code division multiple-access (CDMA) systems, maximum total throughput assuming a matched filter receiver can be obtained by spreading with low-rate error control codes. Previously, orthogonal, bi-orthogonal and super-orthogonal codes have been proposed for this purpose. We present in this paper 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 super-orthogonal codes as well as conventionally coded and spread systems. We also show that the proposed low rate codes will give simple encoder and decoder implementations. With these codes, any rate 1/n, n⩽512, are obtained for constraint lengths up to 11, resulting in a more flexible and powerful scheme than those previously proposed.



Denna post skapades 2006-09-12. Senast ändrad 2013-06-13.
CPL Pubid: 15929

 

Läs direkt!


Länk till annan sajt (kan kräva inloggning)


Institutioner (Chalmers)

Institutionen för signaler och system, Kommunikationssystem

Ämnesområden

Information Technology

Chalmers infrastruktur