Code-spread CDMA using maximum free distance low-rate convolutional codes

@article{Frenger2000, abstract = {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}, author = {Frenger, P. and Orten, P. and Ottosson, T. }, booktitle = {Communications, IEEE Transactions on}, citeulike-article-id = {2147558}, journal = {Communications, IEEE Transactions on}, keywords = {cdma, cicdma}, number = {1}, pages = {135--144}, posted-at = {2007-12-19 18:04:10}, priority = {2}, title = {Code-spread CDMA using maximum free distance low-rate convolutional codes}, url = {http://ieeexplore.ieee.org/xpls/abs\_all.jsp?arnumber=818881}, volume = {48}, year = {2000} }

TY - JOUR ID - Frenger2000 L3 - citeulike-article-id:2147558 TI - Code-spread CDMA using maximum free distance low-rate convolutional codes T2 - Communications, IEEE Transactions on JF - Communications, IEEE Transactions on VL - 48 IS - 1 SP - 135 EP - 144 N2 - 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 KW - cdma KW - cicdma AU - Frenger, P AU - Orten, P AU - Ottosson, T PY - 2000/// UR - http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=818881 ER -