TY - JOUR
T1 - Binary-Code-Allocation scheme in DS-CDMA systems
AU - Kwan, Ho Yuet
AU - Lok, Tat M.
N1 - Funding Information:
Manuscript received November 1, 2005; revised February 8, 2006. This work was supported in part by a direct grant from CUHK and Earmarked Grants (CUHK4217/03E and CUHK4170/04E) from the Research Grants Council of the Hong Kong Special Administrative Region. The review of this paper was coordinated by Prof. J. Shea.
PY - 2007/1
Y1 - 2007/1
N2 - In this paper, we consider a simple binary-transmitter adaptation in direct-sequence code-division multiple-access systems. We propose a binary-code-allocation scheme for reducing the multiple-access interference (MAI). In this scheme, a user is given an orthogonal binary sequence set. By choosing a better sequence from the sequence set, the user can maximize his/her signal to interference ratio. We examine the scheme analytically by both exact analysis and approximation in equal-power synchronous cases. Theoretically, it is found that the scheme can significantly reduce the MAI. It only involves a few bits of feedback information for the transmitter to adjust the sequences. The scheme can also be modified for multiuser adaptation in asynchronous channels. In a multiuser adaptation, simulations show that the users would have a significantly improved performance against the MAI, and the system throughput can also be increased. It is shown that this binary-code-allocation scheme is a simple, widely applicable, and robust binary-sequence-adaptation scheme.
AB - In this paper, we consider a simple binary-transmitter adaptation in direct-sequence code-division multiple-access systems. We propose a binary-code-allocation scheme for reducing the multiple-access interference (MAI). In this scheme, a user is given an orthogonal binary sequence set. By choosing a better sequence from the sequence set, the user can maximize his/her signal to interference ratio. We examine the scheme analytically by both exact analysis and approximation in equal-power synchronous cases. Theoretically, it is found that the scheme can significantly reduce the MAI. It only involves a few bits of feedback information for the transmitter to adjust the sequences. The scheme can also be modified for multiuser adaptation in asynchronous channels. In a multiuser adaptation, simulations show that the users would have a significantly improved performance against the MAI, and the system throughput can also be increased. It is shown that this binary-code-allocation scheme is a simple, widely applicable, and robust binary-sequence-adaptation scheme.
KW - Binary sequence adaptation
KW - Orthogonal sequence set
UR - http://www.scopus.com/inward/record.url?scp=33847688451&partnerID=8YFLogxK
U2 - 10.1109/TVT.2006.883804
DO - 10.1109/TVT.2006.883804
M3 - Article
AN - SCOPUS:33847688451
SN - 0018-9545
VL - 56
SP - 134
EP - 145
JO - IEEE Transactions on Vehicular Technology
JF - IEEE Transactions on Vehicular Technology
IS - 1
ER -