IEICE TRANSACTIONS on Communications
Superimposed Frequency Symbol Based Adaptive Downlink OFDM with Frequency Spreading and Equalization
Summary :
In AMS/OFDM systems, a base station controls the modulation level of each subcarrier with feedback information (FBI), and then, adaptive modulated packets are transmitted from the base station to the mobile station. In this case, the mobile station requires modulation level information (MLI) to demodulate the received packet. The MLI is generally transmitted as a data symbol, so the throughput is degraded. To overcome this problem and increase the total throughput, in this paper, we propose superimposed frequency symbol based adaptive OFDM with frequency spreading and equalization. In the proposed system, each S/P transformed signal is spread by orthogonal spreading codes and combined. This means that each subcarrier holds several superimposed S/P transformed signals with the same power rate. In this case, the frequency-selective faded subcarriers obtain the same power rate for each S/P transformed signal. Therefore, the detected signals also obtain the same SINR, and as a result, we can assign the same modulation level for each frequency symbol spreading block. Hence, the proposed system requires only one piece of FBI and MLI for each frequency symbol spreading block, as compared with conventional adaptive OFDM.
- Publication
- IEICE TRANSACTIONS on Communications Vol.E89-B No.2 pp.500-508
- Publication Date
- 2006/02/01
- Publicized
- Online ISSN
- 1745-1345
- DOI
- 10.1093/ietcom/e89-b.2.500
- Type of Manuscript
- PAPER
- Category
- Wireless Communication Technologies
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Keyword
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Chang-Jun AHN, Hiroshi HARADA, Yukiyoshi KAMIO, "Superimposed Frequency Symbol Based Adaptive Downlink OFDM with Frequency Spreading and Equalization" in IEICE TRANSACTIONS on Communications,
vol. E89-B, no. 2, pp. 500-508, February 2006, doi: 10.1093/ietcom/e89-b.2.500.
Abstract: In AMS/OFDM systems, a base station controls the modulation level of each subcarrier with feedback information (FBI), and then, adaptive modulated packets are transmitted from the base station to the mobile station. In this case, the mobile station requires modulation level information (MLI) to demodulate the received packet. The MLI is generally transmitted as a data symbol, so the throughput is degraded. To overcome this problem and increase the total throughput, in this paper, we propose superimposed frequency symbol based adaptive OFDM with frequency spreading and equalization. In the proposed system, each S/P transformed signal is spread by orthogonal spreading codes and combined. This means that each subcarrier holds several superimposed S/P transformed signals with the same power rate. In this case, the frequency-selective faded subcarriers obtain the same power rate for each S/P transformed signal. Therefore, the detected signals also obtain the same SINR, and as a result, we can assign the same modulation level for each frequency symbol spreading block. Hence, the proposed system requires only one piece of FBI and MLI for each frequency symbol spreading block, as compared with conventional adaptive OFDM.
URL: https://global.ieice.org/en_transactions/communications/10.1093/ietcom/e89-b.2.500/_p
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@ARTICLE{e89-b_2_500,
author={Chang-Jun AHN, Hiroshi HARADA, Yukiyoshi KAMIO, },
journal={IEICE TRANSACTIONS on Communications},
title={Superimposed Frequency Symbol Based Adaptive Downlink OFDM with Frequency Spreading and Equalization},
year={2006},
volume={E89-B},
number={2},
pages={500-508},
abstract={In AMS/OFDM systems, a base station controls the modulation level of each subcarrier with feedback information (FBI), and then, adaptive modulated packets are transmitted from the base station to the mobile station. In this case, the mobile station requires modulation level information (MLI) to demodulate the received packet. The MLI is generally transmitted as a data symbol, so the throughput is degraded. To overcome this problem and increase the total throughput, in this paper, we propose superimposed frequency symbol based adaptive OFDM with frequency spreading and equalization. In the proposed system, each S/P transformed signal is spread by orthogonal spreading codes and combined. This means that each subcarrier holds several superimposed S/P transformed signals with the same power rate. In this case, the frequency-selective faded subcarriers obtain the same power rate for each S/P transformed signal. Therefore, the detected signals also obtain the same SINR, and as a result, we can assign the same modulation level for each frequency symbol spreading block. Hence, the proposed system requires only one piece of FBI and MLI for each frequency symbol spreading block, as compared with conventional adaptive OFDM.},
keywords={},
doi={10.1093/ietcom/e89-b.2.500},
ISSN={1745-1345},
month={February},}
Copy
TY - JOUR
TI - Superimposed Frequency Symbol Based Adaptive Downlink OFDM with Frequency Spreading and Equalization
T2 - IEICE TRANSACTIONS on Communications
SP - 500
EP - 508
AU - Chang-Jun AHN
AU - Hiroshi HARADA
AU - Yukiyoshi KAMIO
PY - 2006
DO - 10.1093/ietcom/e89-b.2.500
JO - IEICE TRANSACTIONS on Communications
SN - 1745-1345
VL - E89-B
IS - 2
JA - IEICE TRANSACTIONS on Communications
Y1 - February 2006
AB - In AMS/OFDM systems, a base station controls the modulation level of each subcarrier with feedback information (FBI), and then, adaptive modulated packets are transmitted from the base station to the mobile station. In this case, the mobile station requires modulation level information (MLI) to demodulate the received packet. The MLI is generally transmitted as a data symbol, so the throughput is degraded. To overcome this problem and increase the total throughput, in this paper, we propose superimposed frequency symbol based adaptive OFDM with frequency spreading and equalization. In the proposed system, each S/P transformed signal is spread by orthogonal spreading codes and combined. This means that each subcarrier holds several superimposed S/P transformed signals with the same power rate. In this case, the frequency-selective faded subcarriers obtain the same power rate for each S/P transformed signal. Therefore, the detected signals also obtain the same SINR, and as a result, we can assign the same modulation level for each frequency symbol spreading block. Hence, the proposed system requires only one piece of FBI and MLI for each frequency symbol spreading block, as compared with conventional adaptive OFDM.
ER -
English
