Adaptive subcarrier block modulation with differentially modulated pilot symbol assistance for downlink OFDM using uplink delay spread

Chang Jun Ahn, Satoshi Takahashi, Hiroshi Harada, Yukiyoshi Kamio, Iwao Sasase

Research output: Contribution to journalArticle

Abstract

In AMS/OFDM systems, base station is in control of the modulation level of each subcarrier, and then, adaptive modulated packet is transmitted from the base station to the mobile station. In this case, the mobile station is required the modulation level information (MLI) to demodulate the received packet. The MLI is generally transmitted as a data symbol, therefore, the throughput is degraded. In an OFDM, the channel response at a particular subcarrier frequency is not supposed to be totally different from its neighboring frequencies, and hence, they must have correlation which depends on the coherence bandwidth of the channel Bc. If we could assign the same modulation level for coherently faded subcarrier block, MLI is required only one time for each subcarrier block. Moreover, we can assign the data on the empty space of pilot signals for increasing the total transmission. In this paper, we propose an adaptive subcarrier block modulation with differentially modulated pilot symbol assistance for downlink OFDM using uplink delay spread.

Original languageEnglish
Pages (from-to)1889-1895
Number of pages7
JournalIEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences
VolumeE88-A
Issue number7
DOIs
Publication statusPublished - 2005 Jul

Fingerprint

Uplink
Orthogonal Frequency Division multiplexing (OFDM)
Orthogonal frequency division multiplexing
Modulation
Base stations
Assign
Throughput
Bandwidth

Keywords

  • Coherence bandwidth
  • DMPSA-ASMS/OFDM
  • MLI
  • RMS delay spread

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Hardware and Architecture
  • Information Systems

Cite this

Adaptive subcarrier block modulation with differentially modulated pilot symbol assistance for downlink OFDM using uplink delay spread. / Ahn, Chang Jun; Takahashi, Satoshi; Harada, Hiroshi; Kamio, Yukiyoshi; Sasase, Iwao.

In: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E88-A, No. 7, 07.2005, p. 1889-1895.

Research output: Contribution to journalArticle

@article{762da40617dc418e874ffd21493bfe32,
title = "Adaptive subcarrier block modulation with differentially modulated pilot symbol assistance for downlink OFDM using uplink delay spread",
abstract = "In AMS/OFDM systems, base station is in control of the modulation level of each subcarrier, and then, adaptive modulated packet is transmitted from the base station to the mobile station. In this case, the mobile station is required the modulation level information (MLI) to demodulate the received packet. The MLI is generally transmitted as a data symbol, therefore, the throughput is degraded. In an OFDM, the channel response at a particular subcarrier frequency is not supposed to be totally different from its neighboring frequencies, and hence, they must have correlation which depends on the coherence bandwidth of the channel Bc. If we could assign the same modulation level for coherently faded subcarrier block, MLI is required only one time for each subcarrier block. Moreover, we can assign the data on the empty space of pilot signals for increasing the total transmission. In this paper, we propose an adaptive subcarrier block modulation with differentially modulated pilot symbol assistance for downlink OFDM using uplink delay spread.",
keywords = "Coherence bandwidth, DMPSA-ASMS/OFDM, MLI, RMS delay spread",
author = "Ahn, {Chang Jun} and Satoshi Takahashi and Hiroshi Harada and Yukiyoshi Kamio and Iwao Sasase",
year = "2005",
month = "7",
doi = "10.1093/ietfec/e88-a.7.1889",
language = "English",
volume = "E88-A",
pages = "1889--1895",
journal = "IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences",
issn = "0916-8508",
publisher = "Maruzen Co., Ltd/Maruzen Kabushikikaisha",
number = "7",

}

TY - JOUR

T1 - Adaptive subcarrier block modulation with differentially modulated pilot symbol assistance for downlink OFDM using uplink delay spread

AU - Ahn, Chang Jun

AU - Takahashi, Satoshi

AU - Harada, Hiroshi

AU - Kamio, Yukiyoshi

AU - Sasase, Iwao

PY - 2005/7

Y1 - 2005/7

N2 - In AMS/OFDM systems, base station is in control of the modulation level of each subcarrier, and then, adaptive modulated packet is transmitted from the base station to the mobile station. In this case, the mobile station is required the modulation level information (MLI) to demodulate the received packet. The MLI is generally transmitted as a data symbol, therefore, the throughput is degraded. In an OFDM, the channel response at a particular subcarrier frequency is not supposed to be totally different from its neighboring frequencies, and hence, they must have correlation which depends on the coherence bandwidth of the channel Bc. If we could assign the same modulation level for coherently faded subcarrier block, MLI is required only one time for each subcarrier block. Moreover, we can assign the data on the empty space of pilot signals for increasing the total transmission. In this paper, we propose an adaptive subcarrier block modulation with differentially modulated pilot symbol assistance for downlink OFDM using uplink delay spread.

AB - In AMS/OFDM systems, base station is in control of the modulation level of each subcarrier, and then, adaptive modulated packet is transmitted from the base station to the mobile station. In this case, the mobile station is required the modulation level information (MLI) to demodulate the received packet. The MLI is generally transmitted as a data symbol, therefore, the throughput is degraded. In an OFDM, the channel response at a particular subcarrier frequency is not supposed to be totally different from its neighboring frequencies, and hence, they must have correlation which depends on the coherence bandwidth of the channel Bc. If we could assign the same modulation level for coherently faded subcarrier block, MLI is required only one time for each subcarrier block. Moreover, we can assign the data on the empty space of pilot signals for increasing the total transmission. In this paper, we propose an adaptive subcarrier block modulation with differentially modulated pilot symbol assistance for downlink OFDM using uplink delay spread.

KW - Coherence bandwidth

KW - DMPSA-ASMS/OFDM

KW - MLI

KW - RMS delay spread

UR - http://www.scopus.com/inward/record.url?scp=26044452134&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=26044452134&partnerID=8YFLogxK

U2 - 10.1093/ietfec/e88-a.7.1889

DO - 10.1093/ietfec/e88-a.7.1889

M3 - Article

AN - SCOPUS:26044452134

VL - E88-A

SP - 1889

EP - 1895

JO - IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences

JF - IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences

SN - 0916-8508

IS - 7

ER -