| Popis: |
An extensive investigation of delta modulation techniques for encoding pictorial data was made. The objective was to determine the parameters of delta modulation systems for various image communication applications by (1) system analysis, (2) computer simulation, and (3) experimentation. The analysis of delta modulation techniques includes one-bit and two-bit systems with both linear and exponential integration. Computer simulations of delta modulation logics conducted were (1) one-bit with linear and exponential integration, (2) two-bit with linear and exponential integration, and (3) most importantly, data-link noise with mentioned systems and also pcm. Images of these simulations are presented for evaluation. An experimental two-bit delta modulation encoder with a sampling rate of 50 mc was constructed and tested. A table of the key parameters of pcm and delta modulation systems is presented. Using this table and the images, the image communication system designer can readily choose the best technique and combination of parameters to fulfill his particular application. (Author) |
