Home Automation. Applications. Products and Standards

Applications. Several applications have been envisioned by designers of home automation systems and standards organizations. The following categories of applications have been presented in the literature:

- Control of homes’ heating, lighting, windows, doors, screens, and major appliances via a TV or TV-like screen.
- Remote control of the house environment via a touchtone key telephone.
- Detectors to identify rooms that have been empty for more than a specified period of time and possibly transfer this information to the security system or regulate the heating of the room.
- Help for the elderly and disabled.

- In the initial phases of research and development efforts, the following applications were identified: Load management;
- Domestic appliance system;
- Environment control;
- Lighting control;

- Security;
- Safety;
- Access control;
- Voice communication;
- Data communication (including telecontrol); and
- Entertainment.

Several other applications that can make use of the communications that exist outside the home include:
- Home banking;
- Information services;
- Working from home;
- Health monitoring (health check, health security);
- Telecontrol (appliances security heating, video recording); and
- Telemetering (gas, electricity, water).

Looking at the previously presented classifications of applications, one sees that there is a big difficulty in finding and imposing the most appropriate classification and identifying non-overlapping definitions, and then identifying functional links between different applications. Entertainment applications usually receive the most attention in standardization activities and market products because a large market already exists that has been accustomed to integration and common formats.

Thus, the integration of audio devices such as DAT players, record players, cassette players, CD/DVD players, radio tuners, microphones, headphones, and remote controls has seen a very large market. The same concepts apply to video equipment; that is, the integration of TV display screens, VCRs, TV tuners, video cameras, video disk players, DVD players, video printers, and satellite dish platforms through a common interface has received considerable attention.

Security applications are the most advanced applications at homes today in terms of providing an integration of controller sensors, actuators, video camera, camera platform, microphones, door phone, push buttons/key access, and timers.

A considerable number of electric utilities have been involved with using advanced techniques of home automation for load management.

Products and Standards. As in many other industries, home automation products were first introduced before a complete set of standards was specified. So in tracing the market and product development, we see a large number of products that do not follow any standard specifications but are absolutely proprietary.

Lonworks. For designers who will be involved in home automation designs, companies like Texas Instruments, Motorola, and Toshiba have been very active in developing the tools and components that will make this process easier.

Home automation systems have borrowed extensively from the developments in the networking community. The idea of using a local area network (LAN) to control and connect devices was implemented in Echelon’s Lonworks.

Lonworks is based on a distributed control LAN using its local operating network (LON). Communications media, network communication protocols, and application software are integrated. The LAN implements a predictive p-persistent CSMA protocol and can handle rates up to 1.25 Mbps. In the physical layer, transceivers for a variety of media are offered. The Neuron C application language, an extension of ANSI C, adds several features that allow efficient input/output (I/O) operations and efficient network management.

International efforts have been under way to develop standards covering the communication between home automation system modules. Most of these efforts use a LAN environment and follow standard layered approaches, such as the ones advocated by OSI.

CEBus. In the United States, the Electronic Industry Association (EIA) recognized the need to develop standards covering all aspects of home automation systems communication. A committee was organized in 1983 to carry out the task. In 1988, a home automation system communication standard known as CEBus (consumer electronic bus) was made available by the EIA committee for comments. It was upgraded and re-released in December 1989 after undergoing several changes. A final document became available in 1992 (1).

The CEBus document covers the electrical and procedural characteristics of systems modules communication. The CEBus powerline technology was one of the first attempts to transport messages between household devices, using the 110-I20VAC electrical wiring in U.S. households. More than 400 companies have occasionally attended the CEBus committee meetings, providing a comprehensive standard, intended for the consumer electronics industry.

The main objectives of CEBus have been:
- Low-cost implementation;
- Home automation for retrofit into existing cabling networks;
- To define minimum subsets per appliance intelligence and functional requirements;

- Distributed communication and control strategy;
- Basic plug-and-play functionality allowing devices to be added or removed from the network without interrupting the communication of other subsystems; and
- To accommodate a variety of physical media.

However, CEBus faced only the home automation area and never offered truly multimedia capabilities. In late 1995, CEBus became part of an umbrella standard known as Home Plug and Play (HPnP).

Home Plug and Play. Additions to the application layer of the original CEBus standards have been made in order to create the HPnP specification, transforming standalone products into interactive network products. This specification is expected to make systems easier to install and combine in a reliable inhome network. Among the objectives to be covered by HPnP standards is transport protocol independence, so more than one networking protocol can be used in the same home.

HPnP has three object types: status, listener, and request objects, which adapt the system in which the status information is given to the other systems. By the use of these objects, products from different producers can be used without detailed knowledge of their inner workings.

An important feature of HPnP is that it enables consumers to install more complex systems incrementally without complicating their use or requiring burdensome upgrades.

X.10. Like CEBus, the X.10 specification defines a communication “language’’ that allows compatible home appliances to talk to each other based on assigned addresses. X.10 is a broadcasting protocol. When an X.10 transmitter sends a message, any X.10 receiver plugged into the household power line tree receives and processes the signal, and responds only if the message carries its address. X.10 enables up to 256 devices to be uniquely addressed, while more than one device can be addressed simultaneously if they are assigned the same address.

HBS. The Japanese home bus system (HBS) has been developed as the national standard in Japan for home automation after several years of research and trials. HBS uses a frequency-division-multiplexing system using coaxial cable. Three bands are used for transmission of control signals: baseband, for high-speed data terminals; subband; and, for transmission of visual information, the FM-TV band. Recent efforts have concentrated on the expansion of the traditional idea of a home automation system into one that incorporates multimedia capabilities by using standard telecommunication services, such as ISDN BRI, and controls that provide low noise and low distortion.

EHS. The European home systems (EHS) specification has been developed under European Commission funding under the ESPRIT program. Its aim was to interconnect electrical and electronic appliances into the home in an open way so that different manufacturers can offer compatible products. An EHS product consists of three parts: a modem chip, a microcontroller, and a power supply. The main power cabling is used to carry the command and control signals at a speed of 2.4 kbps.

Digital information is carried by a high-frequency signal superimposed on the voltage of the main. Sensitivity to electrical noise remains a problem, and filters are necessary to eliminate unwanted interference. Other media used include coaxial cable (to carry frequency-multiplexed TV/digital audio signals and control packets, 9.6 kbps), two twisted pair cables (telephone and general purpose, 9.6 kbps and 64 kbps), radio, and infrared (1 kbps).

EIBA Technologies. The European Installation Bus Association (EIBA) has assumed the role of the integrator in the European market. The EIB system for home and building automation is another topology-free, decentralized system with distributed intelligence, based on a CSMA/CA protocol for serial communication. Currently, various EIBA bus access units for twisted pair are commercially available. The bus access unit includes a transceiver; it locally implements the operating system and caters for user RAM and EEPROM space.

EIBA’s objectives include the development of a unified concept for electrical fitting and home and building management. EIBA is a multivendor body that aims to establish a standard for building system technology on the European market. It makes the EIB system know-how available to members and licensees, provides members and licensees with support and documentation, establishes standards among its members, and specifies appropriate criteria for quality and compatibility, with the help of external test institutes.

It also maintains the position of the EIB Tool Environment (ETE) as an unrivaled platform for open software tool development, at the heart of which is the EIB Tool Software (ETS), offering a common tool for the configuration of EIB installations.

EIB components, actuators, and monitoring and control devices communicate via a standardized data path or bus, along which all devices communicate. Little wiring is required, which in turn results in lower fire risk and minimized installation effort. Home automation systems provided by Siemens (see www.siemens.de) follow the EIBA standards and have several desirable features. Siemens’ Home Electronic System (HES) provides:

- Security due to the continuous control of active processes around the house at the homeowner’s fingertips;
- Economy in the use of utilities such as water, electricity, and heating energy;
- Convenience through simplifying operation and reducing the burden of routine tasks; and
- Communication by integrating the household management system into external communications facilities.

IEEE 1394. In order to combine entertainment, communication, and computing electronics in consumer multimedia, digital interfaces have been created. Such is the case of IEEE 1394, which was conceived by Apple Computer as a desktop LAN, and then was standardized by the IEEE 1394 working group.

IEEE 1394 can be described as a low-cost digital interface with the following characteristics:
- High speed. It is able to achieve 100 Mbit/s, 200 Mbit/s, and 400 Mbit/s; extensions are being developed to advance speeds to 1.6 Mbit/s and 3.2 Mbit/s and beyond.

- Isochronous support. Bandwidth for time-sensitive applications is guaranteed by a deterministic bandwidth allocation for applications such as real-time video feeds, which otherwise could be disrupted by heavy bus traffic.

- Flexible topology. There is no central bus supervision; therefore, it is possible to daisy-chain devices.
- Hot-plug capability. There is no need for the user to configure node IDs or unique termination schemes when new nodes are added; this action is done dynamically by the bus itself.

- Cable power. Peripherals of low cost can be powered directly from the IEEE 1394 cable.
- Open standard. The IEEE is a worldwide standards organization.
- Consolidation of ports of PCs. SCSI, audio, serial, and parallel ports are included.

- There is no need to convert digital data into analog data, and loss of data integrity can be tolerated.
- There are no licensing problems.
- A peer-to-peer interface can be provided.

The EIA has selected IEEE 1394 as a point-to-point interface for digital TV and a multipoint interface for entertainment systems; the European Digital Video Broadcasters (DVB) have selected it as their digital television interface. These organizations proposed IEEE 1394 to the Video Experts Standards Association (VESA) as the home network media of choice. VESA adopted IEEE 1394 as the backbone for its home network standard.

PLC. At the end of 1999, the Consumer Electronics Association (CEA) formed the Data Networking Subcommittee R7.3, and began work on a High-speed PowerLine Carrier (PLC) standard. PLC technology aims to deliver burst data rates up to 20 Mbps over powerline cables. However, like CEBus and X10, PLC shares the same power network with motors, switch-mode power supplies, fluorescent ballasts, and other impairments, which generate substantial impulse and wideband noise.

To face this difficult environment, different technologies take widely differing approaches depending on the applications they are pursuing. Technologies and algorithms including orthogonal frequency- division multiplexing (OFDM), rapid adaptive equalization, wideband signaling, Forward Error Correction (FEC), segmentation and reassembly (SAR), and a token-passing MAC layer are employed over the powerline physical layer technologies in order to enhance transmission robustness, increase the required bandwidth, guarantee the quality, and provide both asynchronous and isochronous transmission.

HomePlug. The HomePlug Powerline Alliance is a rather newly founded nonprofit industry association established to provide a forum for the creation of an open specification for home powcrlinc networking products and services. The HomePlug mission is to promote rapid availability, adoption, and implementation of cost-effective, interoperable, and specifications-based home power networks and products enabling the connected home.

Moreover, HomePlug aims to build a worldwide standard, pursuing frequency division for coexistence with access technologies in North America, Europe, and Asia. For medium access control, Homeplug 1.0 extends the algorithm used in IEEE 802.11 to avoid collisions between frames that have been transmitted by stations (2).

HomePNA. HomePNA is defined by the Home Phoneline Networking Association in order to promote and standardize technologies for home phone line networking and to ensure compatibility between home-networking products.

HomePNA takes advantage of existing home phone wiring and enables an immediate market for products with “Networking Inside.’’ Based on IEEE 802.3 framing and Ethernet CSMA/CD media access control (MAC), HomePNA v 1.0 is able to provide 1 Mbps mainly for control and home automation applications, whereas HomePNA v2.0 (3), standardized in 2001, provides up to 14 Mbps. Future versions promise bandwidths up to 100 Mbp/s.

 






Date added: 2024-02-27; views: 136;


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