Transmission of graphic image data to mobile terminals

This type of service is easily accommodated within conventional data communication networks which have adequate transmission rates and low probability of transmission errors. However, these services cannot be applied directly to mobile terminals because of the limited capacity of the mobile channels and the high rate of transmission errors caused by multipath (Rayleigh) fading. The system described uses a low bit-rate source code to represent line diagram graphic images. The encoded line diagram test images have been subjected to different mobile channel conditions and the quality of the received line diagram images evaluated subjectively, both with and without the application of error coding techniques. The aim was to obtain a suitable error control code to protect the image data such that the reproduced line diagram images are acceptable to the users under adverse mobile channel conditions