QUALCOMM Offers QChat `Push-to-Talk' Technology for Mobile Phones Using Voice-Over IP Architecture on 3G CDMA Networks

January 11, 2002

What is QChat

The QChat software application is a product within QUALCOMM Internet Services (QIS), a division of QUALCOMM Incorporated, and was publicly announced today (see related press release dated January 10, 2002).

QChat handset and server software allow users to almost instantaneously connect with other QChat users on third-generation (3G) Code Division Multiple Access (CDMA) systems anywhere in the world with the push of a button. It provides half duplex communication between QChat-capable phones. It enables one-to-one (private) and one-to-many (group) calls over 3G CDMA networks.

QChat uses standard voice-over Internet protocol (VoIP) technologies. This means sending voice information in digital form over IP-based data networks (including CDMA) in discrete packets rather than the traditional circuit-switched protocols of the public switched telephone network (PSTN).

How QChat Works

QChat enables communication to begin with the press of a push-to-talk (PTT) button on the handset, as opposed to a standard wireless call. It creates a call by combining separate point-to-point connections between each IP endpoint at a managing entity known as the QChat Applications Server, deployed on the carrier's IP Wide Area Network (WAN).

Pressing the PTT button originates a call to the target QChat user and provides the originator with information indicating the availability of the target user. If the target user is available, the originator receives an immediate indication that the target user is available and the originator can begin speaking. The originator's voice is then sent through the carrier's network to the target user's handset. Initiating a call to a QChat user who is not available will simply result in a negative response tone rather than a busy signal or voice mail.

QChat offers these major advantages:

-- Support for over-the-air upgrade of QChat client software via the wireless download feature of the Binary Runtime Environment for Wireless(TM) (BREW(TM)) platform;

-- Dynamic management of group membership by subscribers -- who will be able to add or remove participants at any time, on their handset;

-- Ad hoc creation of chat groups on the handset, in addition to the standing groups that an administrator may establish;

-- Easy implementation of the user interface in multiple languages.

QChat on the Handset is a BREW Application

The QChat client requires a BREW-enabled handset and also requires access to a 3G CDMA system. This means that QChat services will be delivered on products from a wide variety of CDMA equipment vendors.

QChat is written as a BREW application and will only be deployed on BREW-enabled handsets. QChat users will also have the ability to access BREW-enabled applications as offered by their carrier. Users will have access to both QChat and BREW-enabled data applications as the BREW platform manages the intersection of data and telephony features on a mobile handset.

QChat Users

QChat's features provide a complete PTT system that equips users with an easy to use virtually instantaneous communications functionality. QChat users are expected to range from those who simply want the ability to communicate immediately with others across distances, to commercial users needing reliable means of communication between co-workers, clients or offsite contacts. QChat technology also will provide an entirely new realm of efficiency to enterprises facing time-critical situations, including medical and emergency response personnel.

Origin of QChat

QChat was developed by QUALCOMM to provide a reliable method of instant connection and two-way communication between users at different locations. Before cellular networks, this type of communication was limited to walkie-talkies and two-way radios, which use frequencies that limit transmission distances.

Wireless networks became widespread globally in the 1990s, and QUALCOMM began leading the industry in developing digital wireless communications products and services based on its CDMA digital technology. This expansion led to the development of new products built to enhance wireless networks and to deliver advanced digital communication devices.

When offered by a wireless carrier on its 3G CDMA network, QChat allows PTT functionality for subscribers of QChat-based services on their BREW-enabled wireless phones.

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