Resynchronization of Modified JPEG Using a Power Allocation Scheme in a Direct Sequence CDMA System

ETRI Journal

关键词: Error recovery;    Resynchronization;    CDMA;    Power Allocation;    Modified JPEG;   

Others  :  1184525
DOI  :  10.4218/etrij.02.0202.0503

【 摘 要 】

In this paper, we discuss recovery schemes for errors occurring when image data encoded with variable length coding (VLC) is transmitted through additive white Gaussian noise (AWGN) and multiple–access interference in direct sequence code division multiple access (DS/CDMA) systems. VLC such as JPEG is so sensitive to channel errors that severe degradation in decoded images occurs even if only one or two bits have errors. This is due to the loss of synchronization at the image decoder. We propose a resynchronization scheme using a power allocation method in wireless DS/CDMA transmission. Through simulation, we know that the proposed method has a more robust resynchronization capability and higher objective and subjective quality than the conventional method.

   

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