TY - JOUR
T1 - Exact performance analysis of hybrid adaptive modulation schemes in multi-channel system
AU - Lee, Sang Do
AU - Ko, Young Chai
N1 - Funding Information:
Manuscript received October 29, 2008; revised December 1, 2008; accepted January 26, 2009. The associate editor coordinating the review of this paper and approving it for publication was K. K. Wong. S.-D. Lee is with Samsung Electronics, Suwon, Korea (e-mail: sar-dor.lee@samsung.com). Y.-C. Ko is with the School of Electrical Engineering, Korea University, Seoul 136-701, Korea (e-mail: koyc@korea.ac.kr). This research was supported by the MIC(Ministry of Information and Communication), Korea, under the ITRC(Information Technology Research Center) support program supervised by the IITA(Institute of Information Technology Advancement) (IITA-2007-C1090-0701-0019). Digital Object Identifier 10.1109/TWC.2009.080919
PY - 2009/6
Y1 - 2009/6
N2 - In this paper, we analyze the performance of a multi-channel system with the conventional adaptive modulation (AM) and two hybrid schemes, the adaptive modulation with diversity combining (AMDC) and the adaptive modulation with power loading (AMPL), respectively. In order to achieve higher spectral efficiency and more efficient usage of channel resources under the total transmit power constraint and the required bit error rate (BER), the AMDC jointly uses discrete-rate adaptation and diversity combining scheme, and the AMPL jointly uses discrete-rate adaptation and sub-optimal discrete-power loading. We derive exact closed-form expressions of the performance of a multi-channel system with the conventional adaptive modulation (AM) and these hybrid schemes, in terms of the spectral efficiency, the average BER and the outage probability. We also analyze the impact of imperfect channel estimation on the error performance and validate our analytical results by simulations. Numerical results show that both the AMDC and the AMPL offer higher spectral efficiency than the conventional AM, assuming the perfect channel estimation. However, AMDC offers better performance and reliability than AMPL, under imperfect channel estimation with complex Gaussian error.
AB - In this paper, we analyze the performance of a multi-channel system with the conventional adaptive modulation (AM) and two hybrid schemes, the adaptive modulation with diversity combining (AMDC) and the adaptive modulation with power loading (AMPL), respectively. In order to achieve higher spectral efficiency and more efficient usage of channel resources under the total transmit power constraint and the required bit error rate (BER), the AMDC jointly uses discrete-rate adaptation and diversity combining scheme, and the AMPL jointly uses discrete-rate adaptation and sub-optimal discrete-power loading. We derive exact closed-form expressions of the performance of a multi-channel system with the conventional adaptive modulation (AM) and these hybrid schemes, in terms of the spectral efficiency, the average BER and the outage probability. We also analyze the impact of imperfect channel estimation on the error performance and validate our analytical results by simulations. Numerical results show that both the AMDC and the AMPL offer higher spectral efficiency than the conventional AM, assuming the perfect channel estimation. However, AMDC offers better performance and reliability than AMPL, under imperfect channel estimation with complex Gaussian error.
KW - Adaptive modulation
KW - And channel estimation error
KW - Diversity
KW - Multi-channel systems
KW - Power loading
UR - http://www.scopus.com/inward/record.url?scp=67651173069&partnerID=8YFLogxK
U2 - 10.1109/TWC.2009.080919
DO - 10.1109/TWC.2009.080919
M3 - Article
AN - SCOPUS:67651173069
SN - 1536-1276
VL - 8
SP - 3206
EP - 3215
JO - IEEE Transactions on Wireless Communications
JF - IEEE Transactions on Wireless Communications
IS - 6
M1 - 5090001
ER -