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Industrial digital communication networks called fieldbuses are becoming more popular in control system implementations for use in automated manufacturing system. This paper presents an overview of the current state of these fieldbus networks. It first gives various advantages of using fieldbus networks over point-to-point connections for control system implementations. Then, the generic ISOIOSI seven-layer communication protocol model is discussed and the deviations from this model for various fieldbus networks are identified. Hardware and software aspects of fieldbus networks are reviewed. Finally, some of the issues in selecting a fieldbus network for a given application are examined.

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The paper details both the coursework and hardware used in a new two-semester sequence of data communication courses under development in the Electronics and Computer Technology (ECT) Program at Bowling Green State University (BGSU). (1) The traditional approach of teaching data communications from a well known topics as signal standards, message syntax, time-based and frequency-based transmission techniques, must now share the undergraduate's attention with newer topics. (2) These topics include administration of servers, workstations and network devices. For the educator, the problem posed by these new topics is the unwanted presence of a potentially large amount of vendor specific and proprietary information within the body of work. The curriculum under development at BGSU attempts to (1) minimize transient, or unnecessary, vendor-specific details, while presenting a strong core of new communication fundamentals that enable students to understand and exercise the (2) information technology basic to server, workstation, and network device operation and interaction.

Several new techniques for reducing the entropy of a Y,I,Q component digital transmission are presented. A discussion of each technique is presented along with objective and subjective analysis. For a set of four test pictures, the average Y,I,Q entropy/pixel was reduced by nearly 80%. An initial component system entropy of 11.08 bits/pixel was reduced to 2.33 bits/pixel. Although exact numeric results are dependent on the separation technique used, the methods presented may be applied to systems using other component separation methods.