A voice-assisted user interface has been introduced in digital wireless terminal devices as a new feature. The voice-assisted user interface allows the user to control his terminal without effort and without eye contact in particular. With a user interface concept of this kind advantage is achieved, for example, in professional users, such as, for example, in authority and vehicle use and among users with limited visual abilities.
A voice-assisted user interface always entails a need to get information without eye contact about the current state of the terminal device and about the arrival of commands directed thereto. As one example such a situation may be mentioned, where the user sets his terminal device to listen to a certain traffic channel. Hereby the rotating tuner is used to select, for example, manually a channel, whereupon the terminal device gives a voice feedback corresponding to the channel selection. If the selection of channel was successful, the selecting actions can be stopped. But on the other hand, if the selection of a channel failed, then the selecting is continued, until the desired traffic channel is found. Such voice feedbacks may be mentioned as another example, which the terminal device gives spontaneously, for example, relating to its state at each time.
For example, storing in state-of-the-art terminal devices of the voice feedbacks used in the situations described above has been very problematic and also generally there are hardly any functioning solutions for its implementation. It has also been regarded as a problem how generally to use voice feedbacks in a voice-assisted user interface and how they could be connected to the control steps taken by the users in the terminal device.
Some implementation models have been proposed for the problem of the described kind. Implementations with the closest application areas are found in connection with the name/voice call functions of some mobile station terminals.
Arranging of voice feedbacks to digital wireless terminal devices with various synthesizer applications is presented as the state of the art. Numerous examples of these have been presented in various publications, of which U.S. Pat. No. 5,095,503 (Kowalski) can be mentioned as an example. However, the main drawback of these implementations is their excessive power consumption, although in fact the objective is to minimize this in mobile terminal devices.
The state of the art is also described in the solution presented in WO Publication 96/19069 (Qualcomm Incorporated), wherein voice feedbacks are arranged to the terminal device, for example, in its post-programmable non-volatile memory. Herein the voice feedbacks are processed in order to reduce their file size before they are stored in the memory. However, such a situation constitutes a problem in this solution, where voice feedbacks ought to be arranged in the terminal device for several different user groups, such as, for example, for different language areas. To this end it has been proposed to equip the terminal device with a special additional memory, which makes the implementation clumsy from the viewpoint both of the user and the manufacturer of the terminal device.