Steps Toward Commercializing Wristwatch PHS

Nippon Telegraph and Telephone Corp. (NTT) has developed the smallest wristwatch type PHS terminal, a refinement of its 1996 prototype.
Amid the trend toward miniaturization of communications handsets, NTT R&D is aimed at producing “wearable communications tools.” NTT expects these tools to free users from the bother and difficulty associated with conventional handsets.
In 1996, NTT developed a prototype wristwatch PHS terminal that could place calls without any key pushing, the result of using voice recognition technology. As the prototype was a wristwatch type, there was no need for users to search in their bags or pockets for the terminal when it rang. Since the release of the prototype, efforts have been made to upgrade and verify relevant technologies. NTT’s efforts have born fruit in the new terminal: it is much smaller and lighter than the prototype, and has much improved functionality including longer call duration, and additional functions including the ability to communicate directly with public cell stations (CSs).

The new terminal has a volume of 30cc, against 40cc for the prototype. It weighs 45g, down from 70g. Call duration has been doubled from 30 minutes to 60 minutes. Stand-by time has jumped to 100 hours from 12 hours. In addition, the new terminal has a built-in battery and antenna: the prototype had them on the wrist-strap. This new design-conscious terminal can also be worn around the neck when the strap is removed.
The technological advances of the new terminal can be attributed to:
1. adoption of a new, low power-consumption LSI that enables voice-recognition and howling suppression
2. adoption of rechargeable lithium ion batteries with high energy density, and an ultra-small antenna.
A speaker/microphone is embedded in the terminal. If users are in a very noisy location, they can use an earphone/microphone plugged into the terminal.
The new terminal has four function keys. To place calls, users speak a name from the pre-registered name lists in the terminal. This is the voice dialing function. Dialing can also be done by speaking the phone number. There are two ways of entering data for voice recognition. The first is via the keys. The second is to voice-record names. With the voice recording, users can register names in any language whereas with key operation only Japanese names can be input. Calls can be placed not only by voicing but also by key operations in the cases where users are in noisy locations or they do not want to let others know whom they are calling. This function has been added because of concern over usage in actual situations.
The new terminals were used experimentally at the Nagano Olympics this February and were received very favorably. The advent of the terminal is expected to lead to the imminent launch of completely new types of products, namely “wearable communications tools” that will break with the conventional concept of the terminal.

Wristwatch PHS terminal specifications
Communications mode: public/private/automatic
Functions:
\ Voice memory dialing
\ Voice dialing
\ Redialing
\ Earphone/microphone plug
\ Holding
\ Time display, operation guidance display
\ Volume/weight: 30cc, 45g (including batteries)
\ Communication time: continuous 60 minutes; 100 hours stand-by
\ Battery: Lithium ion battery (rechargeable)