Progress toward universally accessible public information and communications technologies (PICTs) has been relatively slow. This is primarily due to a complex interaction of market place dynamics combined with technical and human factors issues. Market place dynamics aside, there are technical issues that make it extremely difficult for manufacturers of electronic public service systems such as ABMs, retail point of sale terminals and information kiosks to provide accessible solutions that can be used by all people. There are just too many physical abilities to take into consideration when trying to design a single universal human/machine interface. Recent trends in mobile computing and wireless communications technologies, however, may provide the means for a ‘wireless’ solution to public service accessibility.

The increasing popularity of cell phone based services such as, email, text messaging, Internet access, and in some cases electronic retail transactions, is fueling commercial interest in expanding mobile wireless access to a broader range of public services. This interest is not limited only to cell based services or technology. There have been a number of wireless standards and technologies designed for computer networks, electronic device interconnectivity, and automation and control network applications over the past years. Currently there are only a few leading wireless standards that would be suitable for supporting public service applications and have enough industry momentum to succeed. The chances are that one or possibly two leading wireless technologies will end up supporting most public services, at least for the near future. Already, many wireless device manufacturers are hoping to increase their market share by providing products that incorporate multiple wireless protocols. If the wireless technology for accessing public services can be standardized to some degree then the user interface becomes a key component to the wireless solution.

The ideal scenario is where a single portable device is used to access a wide range of services. Along with the current proliferation of cellular telephones for delivering many of the services currently available, consumers are buying inexpensive portable computing devices with wireless capabilities that can be used for a variety of applications. Unfortunately, wireless enabled consumer products including cell phones and handheld computing devices are not currently accessible to most people with disabilities. It is likely that this will not change anytime soon until changing consumer market demographics or government legislation persuades industry to address product accessibility. Even then, the creation of a single wireless access device that can serve all people with disabilities is still a substantial technical hurdle that would need to be addressed.

Desktop personal computers or PCs have been around for a number of years and have been considered by many as a major enabling technology. The accessibility of most computer systems is due to the multi-media concept embodied in their design, which creates a redundancy of features that (when supported by appropriate peripherals and software) usually ensures that there is at least one interface method to support a person with a disability. As a result, developers of assistive technology have already created a variety of accessible interfaces and software designed to accommodate a wide range of physical disabilities. It has never really been practical or economically feasible to match this flexibility in other types of products such as cell phones, where the feature-sets in each model is chosen with the needs of a specific market in mind. Handheld computers, on the other hand, are essentially small mobile PCs with enough computing power, wireless connectivity and external interfacing capabilities to serve as assistive access devices. For the short term, these platforms are the best candidates for wireless access to public services as there are no significant technical reasons preventing assistive device developers from creating suitable user interfaces, similar to those built for desktop PCs. This would allow people to take their own customized “wireless access device” with them whenever they were out roaming around in the community. The combination of an accessible portable computing device and a wireless connectivity standard for public service systems could result in a universal access solution for many persons with disabilities.

The wireless approach to accessibility maybe both feasible and timely, but which technologies are best suited to accessible applications? There are several wireless standards and technologies that seem to be leading the way in supporting many of the current and new services that are starting to appear. It is not clear at this time which one or combination of technologies will best serve users with disabilities. Also, there have been several unsuccessful disability-driven initiatives that proposed technical standards intended to improve the accessibility of both assistive and consumer electronics. There are basic elements of good universal design in these past initiatives that could be applied to wireless devices to benefit everyone, not just those with disabilities. This document highlights some of the accessibility issues effecting a standardized wireless connection for access to public services.

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2.0 WIRELESS PUBLIC SERVICES FOR PERSONS WITH DISABILITIES

The types of wireless public services that persons with physical disabilities might access are not very different than those designed for the average consumer, with perhaps a few noticeable exceptions. Recent focus group findings identified a number of existing and future wireless services that people with mobility and those with visual impairments would find useful. The services listed are not reliant on any one specific wireless technology. Many of the services do not yet exist but most could be implemented using current technologies. The conceptual user interface presented to the focus groups was a Palm PC or PDA that would be modified for their input and output requirements. The services listed here are in no prioritized order.

Mobile access to transit schedule info and maps
Provide a person with the name of the various buses as they arrive at a stop
Electronic payment of transit fares
Notify a bus driver of a desired destination or notify user of upcoming stops
Direction finding and GPS location info to navigate city streets
Open main doors to public and commercial buildings
Intercom access and control
Call elevators and select desired floor
Announce floor stops
Direction finding info within the building (best access routes for wheelchairs, etc.)
Product identification in retail stores
Pay for retail goods electronically
Purchase tickets from vending machines electronically (including parking machines)
Access automated banking machines
Make voice calls
Access Internet and email services

Obviously these services do not represent a comprehensive list of every conceivable service that may benefit people with disabilities. However, it is fairly representative of the types of daily activities that are important to people with disabilities when they are out in public. The focus group participants stressed the need for security, ease of operation and low cost as key features that would affect their adoption of any technology designed to deliver these services.

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3.0 TECHNOLOGY STANDARDS FOR UNIVERSAL ACCESS

A variety of assistive technologies have been developed over the years that have allowed people with disabilities to have greater control over their home environments. Many of the household items that need to be controlled are often electrical devices such as computers, telephones, TVs, stereos, lights and appliances. Other things that are typically manually operated such as doors, drapes, blinds and windows can be made accessible with the addition of commercially available power options. The greatest challenge for assistive device developers so far has been the design of suitable user interfaces and adapted controls that can provide access to these household devices. When taking into consideration the wide range of sensory and physical limitations of the users, the devices to be operated and the technological options available, the environmental control systems that are developed end up being designed for a particular disability, are task and product dependent, and expensive to manufacture.

This ongoing battle of always having to adapt existing consumer products has lead to several research initiatives that have proposed “universal access” standards to enable better connectivity between assistive and consumer electronic devices. Some of these initiatives have resulted in general recommendations for product designs while others have gone as far as describing specific hardware and software designs as well as “linking protocols” for connecting assistive devices to each other as well as to commercial products. It is important to note that these standards differ from the communications standards or ‘wireless protocols’ described in the following section four. These standards were primarily designed to govern the way information is formatted and exchanged between two electronic devices in order to more effectively support a user with a disability. They were intended to work with most communication links. Whereas wireless protocols specify the characteristics of the link itself and primarily govern such things as the power requirements, frequency range of operation, encoding/decoding scheme, and throughput capacity in order to carry data in a reliable and secure manner.

Below is a summary of three of the more promising initiatives that have come out so far. The Archimedes and the URCC projects unfortunately failed to garner any significant consumer electronics industry support and the implementation of these standards required a level of commitment and industry cooperation that was rare for the time. In spite of these failures the basic technical concepts have survived and have been passed on to the current V2 initiative. Many of the researchers behind the two earlier initiatives have been involved with the development of the technical standards under V2, as can be seen by the use of similar terminology in the V2 documentation.

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3.1 Archimedes Project

The Archimedes Project, founded at Stanford University in 1990, was made up of a multidisciplinary research group at Stanford's Center for the Study of Language and Information (CSLI). The mission of the Archimedes Project was to ensure everybody would be able to access information regardless of individual needs, abilities and preferences. The project work ranged from theoretical and philosophical studies through to practical development of special hardware, software and a communications protocol. The proprietary nature of the protocol combined with the lack of applications for able-bodied individuals limited industry acceptance of the protocol.

The Archimedes Project developed the Total Access System (TAS) which provided the core technology for allowing any person to access any computer or electronic device. The most important property of the TAS was the ability for system components to automatically identify themselves to each other, declare their capabilities and needs, and use the information to configure the user interface for each application. The Total Access System was built around three basic components, an Accessor (user input device) which provides an appropriate interface to the person, a Total Access Port (TAP) which provides a universal interface to the target computer or electronic device and a standardized connection between any accessor and any TAP.

The Total Access System (TAS) simplifies the task of making computer workstations and other electronic devices accessible to people with disabilities. Unlike most of the existing access techniques, the TAS operates outside of the computer that is being made accessible. The TAS provides full control of the target system without any modification of the existing hardware or software. This drastically simplifies the task of providing access by clearly separating the functions performed by the target computer system from the access needs of the disabled user.

The TAS consists of two main components: a small box called the Total Access Port, or TAP, which is inserted in the keyboard and mouse lines of the target computer, and a personal input/output device called an accessor. A standardized communications protocol makes it possible for any accessor to interact with any TAP. By emulating all of the keyboard and mouse functions of the target computer, the TAP allows additional keyboard and mouse activities to be entered in a totally transparent manner. The accessor provides each user with an interface that matches his or her individual needs, abilities, and preferences.

Many different technologies and strategies are required to accommodate all of the different disabilities and to satisfy individual needs and preferences of users. The project goal was to develop a range of accessors that could respond to anything a person is able to do, and could deliver information through any sense to which the user is able to respond. The current generation of accessors uses conventional desktop or laptop computers running special software to perform functions such as speech recognition, head tracking and eye tracking. The hope is that stand-alone accessors will eventually be built that include only the components and functions that are necessary.

Fast and efficient communications between any accessor and any TAP is an essential requirement for the TAS. This is currently achieved by using an RS232 serial cable connection. The goal, however, is to eventually provide the option of using wireless connections between any accessor and any TAP. This will be achieved in the next generation of the TAS by designing each accessor and each TAP as a node on a LonWorks network. This will provide "plug-and-play" capabilities that allow complex user interfaces to be easily and quickly assembled from accessor "building blocks." The LonWorks network was primarily designed for environmental automation systems in large buildings and supports options for using cable, IR, RF and power line connections.

The current version of the TAS uses a serial cable connection between a single accessor and a single TAP. A voice-operated switching box is available for individuals who need to use their accessor with multiple target systems. This automatically routes the output of the accessor to the appropriate TAP. A different connection strategy is being developed for the next version of the TAS.

Instead of direct one-to-one connections, a small local area network will connect accessors and TAPs in a dynamic, programmable, user-controlled environment. The TAS system is basically independent of the particular network that is employed. A TAS protocol, called TAScloud, provides intelligent communications between all of the TAS components. This is an extremely significant development in the field of accessibility because it enables disabled users to mix-and-match accessors to suit their individual needs, abilities and preferences. A preferred combination of accessors can be used to access any target system connected to the network by a TAP.

When the user decides to work on a particular target computer, the TAScloud will connect the user's accessor to the appropriate TAP. The TAP will then transmit information to the accessor, which uses the data to automatically configure itself to match the characteristics of the target computer. It will be possible for more than one accessor to be talking to a specific TAP at any time. Accessors will communicate with each other over the network to coordinate the performance of complex tasks. This will allow the user to select the best tools for each task or subtask. For example, a user might edit text by moving the mouse cursor with a head pointer and clicking the buttons by voice. Another user might perform the same editing task by moving the mouse by hand and clicking the buttons with a foot switch.

It will be possible for the behavior of input and output accessors to be changed at any time. This will allow a single accessor to simultaneously work with several target systems. The TAScloud will provide the accessor with the data it requires for reconfiguring itself each time it connects to a different target system.

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3.2 URCC - The Universal Remote Console Communication

The URCC (Universal Remote Console Communication) or Ez-Remote, was a communications standard developed at the Trace Center which would allow assistive devices to control various electronic products such as thermostats, televisions, telephones, microwaves and lamps. The URCC was a remote console protocol (versus just a remote control). That is, with an URCC compatible remote console the user can both view information from all of the displays on a target device as well as operate all of its controls. Like the TAS, this protocol required that the assistive devices and the products being controlled both incorporated the URCC so that configuration information could be exchanged allowing the user interface to provide only the necessary control options for that specific product. Once again, the reluctance of manufacturers’ to build the protocol into their existing products resulted in only limited deployment of URCC.

Target devices can be:

Televisions
VCRs
Stereos
Kiosks
Telephones
Thermostats
Microwave ovens
Or any other device that has electronic controls and displays

Remote consoles can be:

A special hand-held device designed specifically for this purpose.
A laptop computer
An electronic pocket calendar
Personal digital assistant (PDA)
Or any other electronic device with controls and a display of some type

The display on the remote console need not be a visual display - an entirely audio system could be used. In fact, a system could be built that could allow you to operate appliances directly over the telephone (you'd phone the "remote console", which would then allow you to interact with the target devices).

Since an URCC based controller gets the information about what controls are available on a target device from the target device itself, the URCC-based controller:

does not have to be pre-programmed for different appliances
can handle products (target devices) with any arbitrary number of buttons or controls (including the hundreds that might be on a touchscreen-based product)
provides the exact name for each function (e.g., you never have to remember, as you do with some remote controls, that for Device 1 the button labeled "A" represents the control for turning on the sleep mode, but for Device 2 it represents surround sound).

The URCC Protocol is simple and straightforward, containing just a small number of powerful and versatile commands and data formats. The URCC is a communication protocol, and as such can be used over any transmission medium, that is, it could be used over infrared, RF, or copper wire. The primary use of the URCC at this time, however, is envisioned as being in connection with the IrDA (Infrared Data Association) infrared protocol. In this capacity, it would allow individuals to use a single controller (a dedicated controller, or an electronic pocket organizer, or a laptop computer, etc.) with an IrDA port to control any URCC-compatible device (VCR, stereo, thermostat, kiosk, etc.). It would also allow those individuals with disabilities who cannot use the displays and controls on the standard devices to use a special assistive technology as a remote console, allowing them to access and use the standard devices.

Three URCC formats are currently proposed. URCC-1 is text based and presentation-mode independent: that is, it could be used with any size or type of display, including a purely auditory display. URCC-2 allows for a product to send simple touchscreen-like console images to the remote console (in one or more resolutions). URCC-3 allows photo realistic images to be used in image map like fashion.

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3.3 V2 - Information Technology Access Interfaces

The V2 Technical Committee is developing a set of standards for the discovery, selection, configuration, and operation of user interfaces and options. The purpose of these standards is to facilitate the development and deployment of a wide variety of devices (from different manufacturers) that can act as Universal Remote Consoles (URCs) for an equally varied range of devices and services (called "Targets"). In other words, the standards will allow users to control any number of Electronic and Information Technology devices in their environment.

The potential Targets include both devices and services. They may range from things as simple as light switches and thermostats, to more complex items such as audio visual equipment, home appliances, electronics in a car (or other constrained or specialized environments), web-based services, and any other devices or services that can be controlled electronically (or via Communications or Information Technology -- CIT).

Targets may be in the same location as the individual who desires to control the Target through the URC, or the Target can be at any distance from the URC/user, as long as there is some type of network connection between the URC and the Target. This is possible since a URC provides the user with all of the necessary controls as well as the prompts and other information displayed by the Target.

URC functionality could be provided by common devices such as personal computing and Information Technology devices (e.g. laptops, PDAs), telecommunications/mobile wireless devices (e.g. cell phones), etc. They could also be functions implemented in assistive technology devices, or they could be devices that were specially built to function as Universal Remote Consoles. They may also be devices that were built to function primarily as Remote Consoles for a particular family of products (e.g. a Remote Console designed to control components of an integrated home audio-visual system), but would also serve to control any other device that is (V2) URC compatible. They are similar in behavior to universal remote controls today, except

they have much greater function and scope,
they synchronize with the Target in both directions (i.e. they can display the current status of the Target),
they don't need to be programmed by the user, (since they will automatically discover devices that are controllable in a user's vicinity, discover the abstracted user interface of the Targets and present it in the way preferred by the user), and
depending on the networking technology used, they may be used out of sight of the product they are controlling.

The output interfaces provided by URCs could be all visual, all tactile, or all verbal in nature (or any combination thereof), because the (V2) URC specifies the content of a Target user interface independently from the form in which it is presented. Similarly and for the same reason, the control interfaces may be by voice, keyboard, mouse or any other available technology. Thus, URCs could be designed that an individual could talk to and, through the URC, the user could have speech access to any (V2) URC compatible Target listed above without any of these Targets having any voice recognition or voice control functionality themselves. A person might, therefore, be able to say to their URC, "Record channel 12 and show me 'Law and Order'". Or they could be laying in bed and say, "Set the alarm to 6:30 AM, turn the coffee on at 6:00 AM, and turn on the home security system". Or, if one's spouse is already asleep, a person could pick up their PDA or any other (V2) URC compatible URC device and accomplish these same tasks silently either by calling up control panels or by issuing the instructions in writing. (The (V2) URC standard does not provide the natural language control, but would provide all of the information and control necessary for control by a natural language processing URC.)

V2 is currently developing standards for a Universal Remote Console (URC) framework of components that combine to enable remote User Interfaces and remote control of network accessible electronic devices and services through a Universal Remote Console (URC). The following specifications have been developed:

Universal Remote Console
User Interface Socket Description
Presentation Template
Resource Description
Target Properties Sheet

For each of these specifications, a draft standard will soon be available for public review.

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4.0 WIRELESS TECHNOLOGIES TO SUPPORT PUBLIC SERVICES

The leading wireless standards being applied to consumer public service applications could potentially support accessible solutions for people with disabilities. It is important to note that these standards were designed for particular applications primarily defined by the volume of data to be exchanged, range of data transmission and power requirements of the equipment used. This may mean that no one standard or technology will serve all public services. For example, one can easily envision a number of services that could be accessed wirelessly to provide greater independence for persons with disabilities. These might include mobile Internet access, voice communications, retail transactions, automated bank machine transactions, intercom access, control of doors and elevators and emergency calling, to name a few. The data handling capabilities of a wireless link for controlling an elevator or a door would be minimal, one-way transmission over a short range with no security. Downloading information from the Internet on the other hand, especially video, is a much more demanding feat for wireless systems.

Ultimately, the determination of which wireless standard or standards are applied to public service systems will be driven by consumer market dynamics. In some instances, such as elevator control, there may not be a commercial incentive for manufacturers to incorporate wireless interfaces for universal access devices and a case would have to made for government guidance through legislation. However, for the most part, many of the services envisioned for consumer applications will also serve persons with disabilities and the only remaining concern is whether or not the following standards will support the necessary data requirements for an accessible interface.

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4.1 Cellular Telephone Technology

Digital cell phone systems as a whole represent the most wide spread of all the wireless technologies and are based on several telecommunications standards that are still evolving to facilitate the ever increasing demand for higher data throughput. Without delving into the subtle technical differences between each of the cell phone system standards and in order to limit the scope of this document, the term cell phone technology or systems will be used to refer to the group as a whole.

Mobile telephone systems were based upon analogue technologies up until about 1990, although it had become evident much earlier that there would be problems in finding sufficient frequency allocations to satisfy growing demands. Digital systems have almost completely taken over and there are various types of digital cell phone technologies with acronyms that describe their methods for sending and receiving radio frequency data (CDMA, TDMA, GSM, UMTS, etc.). Most of these operate anywhere between 800 and 2000 megahertz on the radio frequency band. Most standard 2G or second generation devices (analog phones being first generation) can transmit data at about 9.6 kilobits per second to 19.2kbps, which is enough for low fidelity voice or a very slow computer connection. Transmission range depends on terrain and operating frequency and may be anywhere between 200 meters to several kilometers. Slightly better performance is offered by the newer 2.5G GPRS systems that provide an average of 28kbps of data throughput, contrary to advertising claims. The latest 3G technology is promising up to 2mbps, which can handle streaming video, two-way voice over Internet Protocol (IP), and Internet content with high-quality graphics.

A number of cell based services, other than voice calls, are currently being researched or have already been implemented on cell phone networks in North America. For example, most service providers now offer text and picture messaging, email and Internet access. E911 emergency location sensing is another feature that allows service providers to pinpoint the location of a cell phone in the event of a 911 emergency call. Some companies are experimenting with cell phones for retail transactions or mobile commerce (m-commerce), ABM access and pay per view video, which are all basically extensions of Internet services.

With 3G technologies there should be few issues around providing the necessary throughput and quality of data for most accessible applications. It is likely that most services would be Internet based rather than direct wireless connections to public systems which maybe overkill for simpler control applications such as intercom, elevator and door access. Although with the proliferation of tiny electronic “server modules”, that have there own Web address and can be connected to almost anything, Internet access to simpler control systems is gaining popularity in automation circles. There is a basic level of security built into the data transmission schemes for cell phone systems, but most service providers looking at very secure applications such as cashless financial transactions are adopting various techniques that add another level of security on top of the existing wireless link.

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4.2 WiFi (Wireless Fidelity)

WiFi products based on the IEEE 802.11 series of standards for Wireless Local Area Networks (WLAN) are primarily aimed at higher data throughput applications for computer networks such as Ethernet connectivity and full Intranet and Internet access. WiFi typically operates in the 2.4 gigahertz frequency band with a data rate of around 11Mbps up to a range of several hundred meters. Market data indicates that WiFi has become the dominant WLAN technology on the market. Numerous WiFi enabled products have been developed and there is an emerging market for WiFi “hot-spots”, various public venues such as airports, hotels, coffee shops and malls where wireless networks have been installed to support people with mobile computing needs. WiFi can certainly handle large amounts of data in a speedy fashion and could easily handle the data requirements for an accessible interface, but there are some issues around data transmission security that are still being addressed. Under certain circumstances a WiFi signal can be eavesdropped upon and the raw data intercepted by an unauthorized party, however, if WiFi is used in conjunction with an Internet protocol then the data encryption schemes that are currently used to enable on-line banking would provide the same level of security. For simple control applications WiFi, like cell phone technology, may be overkill. A hybrid approach, however, may work quite well, where the user is connected to a WiFi interface node or “gateway” to a simpler network of control devices.

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4.3 Bluetooth

Bluetooth was designed for personal area networks (PANs), as a means to replace the cables that connect electronic devices. It is well suited to applications such as synchronizing data between PDAs, PCs, printers, input devices and cell phones. It also supports an audio component for wirelessly connected headsets for cell phones. It operates in the same frequency range as WiFi, has a maximum range of 100 meters (10 meters nominal) and supports a 721 kbps data rate. At this rate, Bluetooth could easily handle control data, public service application data and reasonably good quality audio. Video would not be a viable option, but it is not evident at this time whether video is a requirement for supporting public service interfaces for persons with disabilities.

Bluetooth incorporates an interesting feature that is similar in concept to the V2 standard described earlier. It has an automatic discovery mode in which compatible Bluetooth products identify each other when in close vicinity. It was designed primarily to establish and manage the connection of up to seven devices at one time. Master/slave relationships between devices can be created, determined either by function or by user intervention. This feature involves the use of “profiles” which have been developed in order to describe how implementations of user models are to be accomplished. The user models describe a number of user scenarios where Bluetooth performs the radio transmission. A profile defines options in the Bluetooth protocol that are mandatory for the profile. It also defines parameter ranges for each protocol. The profile concept is used to decrease the risk of interoperability problems between different manufacturers' products. There is no reason why an “assistive device” profile could not be designed that would enable the connection of an assistive access device to a public service system via a Bluetooth wireless link.

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4.4 ZigBee

ZigBee is a relative newcomer to the wireless arena and although it is not a standard that could support an information rich user interface, it is possible that ZigBee enabled products could be part of an infrastructure that is accessed by a smart host that incorporates a higher level wireless interface such as WiFi. This open-standard protocol provides for wireless machine-to-machine communications at low power and low cost. It uses the IEEE's 802.15.4 standard for short-distanced wireless networks, also know as personal area networks, PANs or WPANs. IEEE 802.15.1 and .2 are known as Bluetooth, while 802.15.3a is ultra-wideband (UWB). ZigBee has a radio frequency range of 30 to 225 feet and uses very little power. It’s primarily designed for wireless environmental and automation control applications. ZigBee should have the most impact in the home, rather than in manufacturing or retail. The chips will automate home devices including light switches, fire and smoke detectors, thermostats, appliances, video and audio remote controls, landscaping, and security systems. It will likely beat out the X10 and infrared technologies that are used in home automation today. Unlike the one-way infrared commonly used for remote controls, ZigBee doesn't need a line of sight to communicate; signals could even travel through walls and doors.

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4.5 RFID

Another wireless technology that is gaining some momentum in the commercial arena is RFID (Radio Frequency IDentification) technology. RFID tags are typically unpowered devices and provide data in one direction. RFID readers detect the presence of an RFID tag, access the data contained within, and then provide a preprogrammed response. Basically there is no way for someone carrying an RFID to actively initiate a query of the system’s reader. Currently RFID is used for merchandise or people tracking, building access and egress control and some companies are applying it to special retail applications such as the purchase of gas. While this technology is appropriate for passively exchanging identification information, it is less appropriate for more complex types of public service applications that involve interactive transactions or information access. In spite of this there are some promising and potentially powerful applications for this technology. Researchers in the US are experimenting with a reminder/prompting system for Alzheimers sufferers. There is also an enormous potential for product identification for the blind in various retail environments.

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5.0 UNIVERSAL ACCESS CONSIDERATIONS FOR WIRELESS CONNECTIVITY

The concept of using personal wireless devices to access a variety of public services could result in an accessible solution for persons with disabilities. There are several factors which will affect this development. The key to a successful wireless access solution is simplicity of operation for all users. This predominately applies to the user access device and the service interface. Persons with disabilities who wish to access a public service must have a wireless access device that incorporates an input device and feedback method that will suit the user’s needs. As pointed out briefly in the Introduction, a wirelessly enabled handheld computer is an excellent candidate for such an application, as many of the same techniques used to make desktop computers accessible could be applied to handheld devices. Some work has already been done in this area by several assistive device developers.

There may be some issues around how public service information is presented to someone using a handheld device. The wireless standard or standards supporting public services may have an effect on the format of the information made available to the user. For example, most public services may be provided via the Internet, as it is the most popular protocol currently supported by cell phone networks and WiFi connections. Therefore, the public service interface presented to the user may be in the form of a Web page displayed in a Web browser such as Microsoft’s Internet Explorer or Netscape. Some work has been done to create handheld compatible versions of these programs to scale down the display of information to suit smaller devices as well as proposed standards for speech-enabled Web applications. However, even if a Web page can be condensed into a manageable form, further work needs to be done to ensure that the service providers design their interface content to take into consideration the needs of disabled users. Even though alternative desktop computer access devices have been developed for people with disabilities, their ability to effectively navigate a Web page in a timely manner could be seriously hindered if there is too much information or selection options available.

From the user’s perspective, the wireless link or links that facilitate the wireless interactions, should be seamless and transparent, regardless of whether they are based on a single or multiple standards. The user should be able to simply choose or be automatically presented with an appropriate application from a menu on the wireless access device and then make various selections available to that application. The rest should be invisible. In some cases it may even be desirable to have applications automatically “trigger” when a wireless service is detected, such as when a person approaches a door or elevator. Currently, there are still technical issues around the setup, connection and operational characteristics of wireless products. As many portable computer users have found out, setting up a wireless link using a WiFi card isn’t exactly straightforward. Bluetooth enabled products incorporate an auto-discovery feature which helps alleviate some of the setup and connection issues, but the initial configuration process can still be confusing for many people. This is where auto-discovery techniques outlined in the accessibilty initiatives could be applied in some form to greatly simplify the process and free the user from tedious setup and connecting procedures currently associated with wireless connectivity. Two connecting devices would automatically identify themselves to each other, declare their capabilities and needs, and use the information to configure the control options and user interface for each application.

Although there is great commercial interest in the delivery of various public services over wireless connections, there is no single wireless connectivity standard yet that will serve all public services. Some effort has been made to standardize the technology within certain public service areas, such as retail point of sale terminals, but it is not likely that all public service providers will adopt a single wireless standard. Currently, the trend is to go with the most established wireless technologies available (ie. cell phone networks). The good news is that there are only a couple of wireless standards that are mature enough to be applied to public service applications and they meet the data requirements for most accessible applications. To provide the greatest service coverage may require the use of a hybrid wireless access device that can support several wireless standards. This may seem cumbersome at first and set procedures will have to be simplified, but considering such hybrid devices already exist this may not prove to be too much of a technical hurdle.

It is too soon to know how some of these wireless technologies may be applied to accessible applications that fall outside the realm of the general public such as elevator control and building access. Although the standards that provide for high data throughput may be considered overkill for simple control applications, it may be possible to build low cost receivers that adhere to the standard or protocol and simply react to basic command structures. There are Internet-ready modules available today that work in this way, however, start-up costs maybe a factor in the short term. Another approach might include an interface module that supports a high throughput standard such as WiFi and acts as the front end to a networked system of simpler controllers based on something like the ZigBee standard. Industry will likely lead these developments as commercial interest in automation and environmental control grows. It is also possible that the assistive device industry may lead some of these developments if the concept of accessible personal wireless devices for accessing public services catches on.

Regardless of what hardware and wireless standard is ultimately the winner for public service applications, industry is moving ahead and wireless access to public services is definitely coming. Fortunately, there is equipment available based on the key standards and these products can be evaluated and tested to further examine the issues that could affect the accommodation of persons with disabilities.

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Page modified: November 26 2007 16:54:55