Differential modulated pilot symbol assisted adaptive OFDM for reducing the MLI

Author

Ahn, Chang-Jun ; Takahashi, Satoshi ; Harada, Hiroshi

Author_Institution

Nat. Inst. of Inf. & Commun. Technol., Yokosuka, Japan

Volume

B

fYear

2004

fDate

21-24 Nov. 2004

Firstpage

577

Abstract

In an AMS/OFDM system, base station is in control of the modulation level of each subcarriers 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. Moreover, it is necessary to have some transmission delay times and the processing time to make an adaptive modulation command (AMC) using feedback information (FBI). With the FBI delay and processing time, the system performance might be degraded. To reduce these problems, in this paper, we propose a differential modulated pilot symbol assisted adaptive OFDM for reducing the MLI.

Keywords

OFDM modulation; adaptive modulation; channel estimation; AMC; AMS-OFDM system; FBI; MLI; adaptive modulated packet; adaptive modulation command; differential modulated pilot symbol assisted adaptive OFDM; feedback information; modulation level information; Adaptive control; Base stations; Control systems; Degradation; Delay effects; Feedback; OFDM modulation; Programmable control; System performance; Throughput;

fLanguage

English

Publisher

ieee

Conference_Titel

TENCON 2004. 2004 IEEE Region 10 Conference

Print_ISBN

0-7803-8560-8

Type

conf

DOI

10.1109/TENCON.2004.1414661

Filename

1414661