Two major categories of CDMA signature codes, namely unitary codes and complementary codes, are of interest. All currently available 2–3G CDMA systems make use of the unitary codes, such as Gold codes, m-sequences, Walsh–Hadamard sequences and OVSF codes, all of which work on a one-code-per-channel basis. On the other hand, a CDMA system based on complementary codes works on a flock-of-codes basis. Each user in such a CDMA system is assigned a flock of codes which should be sent to a receiver via different carriers to reconstruct perfect autocorrelation and crosscorrelation functions. A comprehensive analytical study of a STBC-CDMA system using different spreading codes is given and their bit error rate performance is evaluated and compared with both analysis and simulation under Rayleigh fading and multiple-access interference. The results reveal that a STBC-CDMA system based on complementary codes offers a capacity similar to that achievable in a noise-limited system, while a STBC-CDMA system based on traditional unitary codes suffers serious interference-limited problems even with full STBC diversity gain.
References
-
-
1)
-
H.H. Chen ,
J.F. Yeh ,
N. Suehiro
.
A multicarrier CDMA architecture based on orthogonal complementary codes for new generations of wideband wireless communications.
IEEE Commun. Mag.
,
10 ,
126 -
135
-
2)
-
`The ETSI UMTS Terrestrial Radio Access (UTRA) ITU-R RTT Candidate Submission', , 29 January 1998.
-
3)
-
B.M. Hochwald ,
T.L. Marzetta ,
C.B. Papadias
.
A transmitter diversity scheme for wideband CDMA systems based on space-time spreading.
IEEE J. Sel. Areas Commun.
,
48 -
60
-
4)
-
J. Lahtonen
.
On the odd and the aperiodic correlation properties of the Kasami sequences.
IEEE Trans. Inf. Theory
,
5 ,
1506 -
1508
-
5)
-
T. Ito ,
S. Sampei ,
N. Morinaga
.
M-sequence based M-ary/SS scheme for high bit-rate transmission in DS/CDMA systems.
Electron. Lett.
,
6 ,
574 -
576
-
6)
-
V. Tarokh ,
N. Seshadri ,
A.R. Calderbank
.
Space-time codes for high data rate wireless communication: performance criterion and code construction.
IEEE Trans. Inf. Theory
,
744 -
765
-
7)
-
R. Gold
.
Maximal recursive sequences with three-valued recursive crosscorrelation functions.
IEEE Trans. Inf. Theory
,
154 -
156
-
8)
-
G.L. Stuber
.
(2001)
Principles of mobile communication.
-
9)
-
Tsai, S., Khaleghi, F., Seong-Jun, Oh., Vanghi, V.: `Allocation of Walsh codes and quasiorthogonal functions in CDMA 2000 forward link', Proc. 54th IEEE VTS Conf. (UTC 2001), 2001, 2, p. 747–751.
-
10)
-
S.M. Alamouti
.
A simple transmitter diversity scheme for wireless communications.
IEEE J. Sel. Areas Commun.
,
8 ,
1451 -
1458
-
11)
-
V. Tarokh ,
H. Jafarkhani ,
A. Calderbank
.
Space-time block codes from orthogonal designs.
IEEE Trans. Inf. Theory
,
5 ,
1456 -
1467
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