There is an immediate need to provide enhanced text capabilities for the deaf, hearing impaired, and/or speech impaired communities. This is consistent with an overriding social goal of integrating handicapped individuals into traditional society, which is, in part, perhaps, best illustrated by the two recent statutes passed by the United States Congress and signed by the President of the United States: the Americans with Disabilities Act ("ADA") and the Telecommunications Act of 1996. Among other things, these statutes compel manufactures and telecommunications service providers to enhance existing approaches used by members of the deaf, hearing impaired, and/or speech impaired communities to access and utilize telecommunications networks and systems. For instance, the ADA generally requires that handicapped persons have equal access to public (and, in some cases, private) facilities. Among other things, 47 U.S.C. .sctn. 225 (b)(l) states that the Federal Communications Commission "shall ensure that interstate and intrastate telecommunications relay services are available, to the extent possible and in the most efficient manner, to hearing-impaired and speech-impaired individuals in the United States." Consequently, over the past several years, it has become imperative for telecommunications companies to develop systems, processes, and apparatus that enable members of the deaf, hearing impaired, and/or speech impaired communities to use telecommunications networks and systems.
Deaf, hearing impaired, and/or speech impaired individuals primarily communicate with others via a Telecommunication Device for the Deaf ("TDD"), which is primarily a teletypewriter ("TTY"). One current problem for users of TTY devices is that the number of people who can be called is limited, because TTY users can only have conversations with others who have a TTY device, have access to a TTY device, and know how to use a TTY device. Many business do not have any TTY device or, if they do have a TTY device, there are a limited number available. Alternatively, TTY-to-speech relay services are sometimes used by deaf, hearing impaired and/or speech impaired people to communicate with hearing/speaking persons. These services are generally provided by a group of people, who basically read the TTY text and vocalize the message to the hearing person and also hear the message from the hearing person and type the TTY text to the deaf, hearing impaired, and/or speech impaired person. A major disadvantage of relay services is that they require a third party for each and every telephone conversation, which is especially problematic for the TTY user in personal or financial matters. Moreover, relay readers employed by relay services can also make mistakes, in part, due to the lack of immediate feedback.
One problem with designing new systems, processes, and apparatus is that TDD and TTY devices are, by today's standards, quite slow. Specifically, in the age of 33.4K (baud modems, Digital Simultaneous Voice and Data ("DSVD"), and 64 Kbits per channel BRI/PRI, a TTY uses the Baudot format consisting of 5-bit words transmitted at a rate as slow as 45.45 bits per second, which is a TDD standard. These signals do not have any carrier and only support 38 characters. Numbers and punctuation characters are generally sent after a shift character is sent to change the character mode to a number mode, so as an example, the number "3" and the letter "E" are both represented by the same code (00001). The difference is dependent on the mode each TDD device is in. If the mode of the TDD devices used in a conversation do not match, the result is garbled words. This problem is exacerbated with the fact that the standards are not likely to change for a variety of reasons. In particular, the existing standards are reliable in that the slow speed will work on almost any quality of a telephone line. In fact, TDD devices routinely use an acoustic coupler to connect to the public network. It can be easily read, as it is received, which is important, because most TTY devices are equipped with a small digit window that shows only one line of text. In addition, existing equipment implementing the standard are relatively inexpensive at about $225.00/device.
Existing designs and procedures have other problems as well.