Page 234 - Handbook of Electronic Assistive Technology

Chapter 8 • Assisted Living 223

HomePlug

There are a large number of significant challenges associated with attempting to transmit
data over lines carrying mains voltage, among which are security and interference. In 2000
the HomePlug Powerline Alliance was formed to establish standards for the use of power-
line technologies for home networks. It was created specifically to deal with the problem of
sensitivity to electrical noise on power lines, utilising very high transmission speeds, and
the first standard HomePlug 1.0 was launched in 2001, followed by HomePlug AV for audio/
video in 2005. In 2010 HomePlug Green PHY was created specifically for the smart metering
and energy markets and was adopted by a large group of automobile manufacturers as a
connectivity standard for plug-in electric vehicles. This last standard is being promoted as
an effective way of networking smart appliances. In 2010 the IEEE 1901 standard for high-
speed communication devices via electric power lines, also called broadband over power
lines, was ratified. The standard includes the Intersystem Protocol, which prevents inter-
ference between systems operating in close proximity. Although HomePlug devices can be
of great benefit to users of buildings in relation to providing a cheap and simple method
of transmitting networking and audio/video data to inaccessible building areas, the appli-
ance management facilities are seen as primarily of benefit to service providers and do not
strictly fall within the domain of smart homes as defined and described in this chapter. Other
organisations promoting this area include Universal Power Line Association and HD-PLC.

Radio Frequency

Wireless data communication using the radio frequency range is common place in today’s
society. It is generally expected that a WiFi network will be available to us for our high-
speed data requirements in urban public spaces, and the vast majority of homes with a
broadband connection will have their own WiFi network. The benefits of wireless data
communication are clear. The lack of cabling requirement and the associated convenience
have clear potential benefits for the installation of a smart home system, although there
are also clear issues that require addressing such as interference, security and robustness
(Wang et al., 2014). There are many RF-based home control systems commercially avail-
able but this chapter will concentrate on those that offer open source or licensed protocols.
As was mentioned, all the organisations that offer bus-based systems also offer com-
plimentary RF protocols. This section will concentrate on those other protocols developed
specifically for application in the RF domain that are considered most directly relevant to
smart home systems.

Z-Wave
Z-Wave was developed specifically for the home automation market by Zen-Sys and
acquired by Sigma Designs in 2008. It is a low-power, low-latency wireless mesh net-
work. A mesh network can use intermediate devices called nodes to assist a command
in reaching its intended destination. Z-Wave devices can do so by attempting multiple
routes, which are defined in a table. The system operates in the sub-1-GHz band and is