Telephone
Operator Services is a department within telephone companies
that provides information requested by individual users
as needed to make telephone calls. Directory Assistance
(DA) is an example of these services as supplied by telephone
companies. The user calls the Directory Assistance number
to request telephone numbers of individuals or establishments.
Operators then respond with the appropriate listed number.
This service was originally provided by operators who
used the paper method, i.e. telephone directory books,
to find the desired listing.
Printed telephone directories for operators were replaced
by computer systems in the 70's. Directory Assistance
Operators keyed in sufficient name and address information
for the computer to retrieve the listing and display it
on a CRT monitor. Replacing the books with computers reduced
the search time needed to find the listing.
Today,
more of the functions performed by the Directory Assistance
operator are being replaced by computers
equipped with speech recognition capability. This
latter stage requires economical computer hardware with
performance capable of performing the large number of
calculations in real-time required by speech recognition
algorithms.
Callers were not aware of any difference in directory
assistance (DA) service when the computer listed
data base replaced the directory books for the DA Operator.
Later, there was a minimum impact on the caller when
a recorded voice greeted them and a synthesized voice
was used to give a 'preliminary prompt' and announce
the listing found. The DA Operator is still in contact
with them to narrow down the possible listings to the
one desired.
Although
the callers' Telephone Directory has instructions for
reaching the appropriate DA Bureau, they may not remember
how to do it, or the directory may not be immediately
available when using a coin operated, car, or cellular
phone. Furthermore, they may not know the area code
of the party they wish to reach. Hence they may simply
just dial "411" or "0" for the operator.
SPEECH
RECOGNITION
Once the call is received at the central office, an
automatic greeting and a recorded "prompt" are played,
such as "For what city, please?" The caller then responds
with the name of the city where his party lives, such
as "Minneapolis."
This response is then automatically recognized by the
FGC Speech Recognition
Server and routed automatically to the operator
team that handles Directory Assistance requests for
the Minneapolis locality. In order to provide such service
efficiently, the system must be capable of speaker independent
speech recognition and must be able to recognize the
names of all the states and thousands of individual
cities and localities.
Telephone
Company Operator Service Applications
Directory
Assistance Automation
