Abstract of Thesis Presented to the Graduate School

of the University of Florida in Partial Fulfillment of the

Requirements for the Degree of Master of Science

HOME NETWORKING AND HOME AUTOMATION TECHNOLOGIES

By

Luis F. Montoya

August, 1999

Chairman: Dr. Haniph Latchman

Major Department: Department of Electrical Engineering

This work was inspired by the recent developments in computer communications and its accessibility to the regular consumer. Personal computer penetration in the American household is greater than 45%, with a great number of those having a second computer and with prices of computers at a historic low this penetration tends to increase dramatically. Most of the appliances and consumer electronics products available today have digital controlling circuitry, which makes the home a ripe environment for a digital home network.

The power line is a ubiquitous media in the household, is considered the obvious choice as a home network transport media. However, inherent physical limitations and the large amount of noise present on this media, makes it unpractical for reliable high speed communications and is used mainly for non-critical applications such as lighting control, clock synchronization and some utility power demand applications.

Other media are taking center stage on the home networking industry, most of them geared toward simplicity of installation and reliability of communications. Among those, the most notable are the phone line, which uses the existing phone line already deployed in more than 95% of the American household to network two or more computers and wireless communication using Radio Frequency (RF). There are groups working on standardization of these new technologies and it is early to tell which of them will be the dominant force in home networking. Obviously, whenever possible, the most reliable and prevalent method for computer communications is by using an Unshielded Twisted Pair (UTP) network, but this is practical only in new constructions when the required wiring can be laid out very inexpensively.

Aside from computer networks, there are several other home networks that deserve special consideration. The Audio/Video (A/V) distribution in the home has not been fully addressed, but the advent of new technologies such as the IEEE 1394 (FireWire) and the new MP3 music file format poses an intriguing new way to digitally distribute A/V around the house at high speed. The Heating-Ventilation and Air Conditioning (HVAC) is getting some attention also, as larger homes being built require zoned systems and the use of smart thermostats indicate the use of a communications network between them and a central controller. The most common protocol used for this purpose is the RS-485, and it will be discussed to some extent in the practical implementation chapter. Finally, a fully networked home can not be left without an Infrared (IR) network. The homeowner wants to have the comfort of controlling the A/V, HVAC or Lighting to name a few, without leaving the room. These can be achieved by the use of an IR remote control in a properly networked residence.

This project describes some of these technologies and in the case of the power line, a more technical description of this media as a viable high-speed communications media is studied. The implementation of a fully integrated home network that takes advantage of today’s technologies is described. The development of a residential gateway that allows the different protocols available to communicate among themselves is the ultimate objective and its fundamentals are proposed in this project.