Title :
Image transmission systems through CDMA channels using spreading sequences of variable-period
Author :
Kohda, Tohru ; Ishii, Katsushi ; Tsuneda, Akio
Author_Institution :
Dept. of Comput. Sci. & Commun. Eng., Kyushu Univ., Fukuoka, Japan
Abstract :
Image transmission systems using spread spectrum techniques are discussed. We transmit DCT coefficients of the image through CDMA channels. Within a limited bandwidth, in order to reduce the error rates of significant bits, we assign spreading sequences of longer period to more significant bits than to less ones. This technique is analogous to the Shannon-Fano encoding. It is found that spreading sequences of variable-period are useful in such image transmissions through CDMA channels
Keywords :
code division multiple access; discrete cosine transforms; image coding; image reconstruction; image sequences; sequences; spread spectrum communication; telecommunication channels; transform coding; visual communication; CDMA channels; DCT coefficients; Shannon-Fano encoding; error rate reduction; image transmission systems; limited bandwidth transmission; reconstructed image quality; significant bits; spread spectrum techniques; spreading sequences; variable period sequences; Bandwidth; Bit rate; Computer science; Decoding; Discrete cosine transforms; Image communication; Image reconstruction; Multiaccess communication; Pixel; Spread spectrum communication;
Conference_Titel :
Spread Spectrum Techniques and Applications Proceedings, 1996., IEEE 4th International Symposium on
Conference_Location :
Mainz
Print_ISBN :
0-7803-3567-8
DOI :
10.1109/ISSSTA.1996.563230
