TY - JOUR
T1 - A novel interference-avoidance code reassignment for downlink two-dimensional-spread MC-DS-CDMA systems with power control
AU - Chang, Chih Wen
AU - Kuo, Chien Cheng
N1 - Funding Information:
Manuscript received September 29, 2009; revised January 31, 2010; accepted Macrh 6, 2010. Date of publication April 5, 2010; date of current version July 16, 2010. This work was supported in part by the National Science Council, Taiwan, under Contracts 96-2221-E-006-020 and 97-2221-E-006-085-MY3. The review of this paper was coordinated by Prof. H. Liu.
PY - 2010/7
Y1 - 2010/7
N2 - In the 2-D time- and frequency-domain spread multicarrier direct-sequenced code-division multiple-access (MC-DS-CDMA) system, maintaining a good code tree structure is the key to controlling the interference level. However, as users come and go, the code tree structure will be fragmented and steeped in a high level of interference. In this situation, an active call may be dropped for not being able to reach a predefined signal quality. To solve this call-dropping problem, we propose a novel code-reassignment strategy to reallocate a low-interferenced code to the could-be-dropped call. This way, not only can this possible call-dropping event be evaded, but also, a low-interferenced 2-D code tree structure can be maintained. The simulation results show that the proposed code-reassignment method can efficiently alleviate the call-dropping problem and boost the call-survival rate simultaneously. It is believed that the proposed scheme fills up an important missing link of the dynamic call-resource management for the 2-D-spread MC-DS-CDMA system.
AB - In the 2-D time- and frequency-domain spread multicarrier direct-sequenced code-division multiple-access (MC-DS-CDMA) system, maintaining a good code tree structure is the key to controlling the interference level. However, as users come and go, the code tree structure will be fragmented and steeped in a high level of interference. In this situation, an active call may be dropped for not being able to reach a predefined signal quality. To solve this call-dropping problem, we propose a novel code-reassignment strategy to reallocate a low-interferenced code to the could-be-dropped call. This way, not only can this possible call-dropping event be evaded, but also, a low-interferenced 2-D code tree structure can be maintained. The simulation results show that the proposed code-reassignment method can efficiently alleviate the call-dropping problem and boost the call-survival rate simultaneously. It is believed that the proposed scheme fills up an important missing link of the dynamic call-resource management for the 2-D-spread MC-DS-CDMA system.
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U2 - 10.1109/TVT.2010.2047329
DO - 10.1109/TVT.2010.2047329
M3 - Article
AN - SCOPUS:77954616099
VL - 59
SP - 3104
EP - 3108
JO - IEEE Transactions on Vehicular Communications
JF - IEEE Transactions on Vehicular Communications
SN - 0018-9545
IS - 6
M1 - 5443643
ER -