Abstract: A wireless personal mobile terminal in a cellular data network includes a packet radio transceiver for communicating with cellular base stations and a paging receiver for receiving paging signals from a paging transmitter serving a large geographical area. The wireless personal mobile message unit has power-saving features built into the signal format. This personal mobile message unit accommodates many communication applications due to the high bandwidth and the low latency achieved in the cellular data network. Low-power operation and wide coverage is achieved using existing one-way paging infrastructure. The wireless personal mobile unit can be achieved inexpensively by modifying a conventional one-way pager.
Abstract: A two-way data network includes a broadcast control sub-network and a cellular data sub-network. The broadcast control sub-network includes a few high-power radio transmitters broadcasting into a large service area. The cellular data sub-network covers the large service area by a number of base stations each servicing a relatively small area. The wireless terminals of the two-way data network monitors the messages in a broadcast control channel at pre-assigned periodic time slots and remain in "sleep" mode at other times. A packet radio transceiver in the wireless terminal sends data to, and receives data from, the cellularized base stations. The broadcast control sub-network is used to notify the subscriber the receipt of a message. In responding to the notification, the location of the subscriber's wireless terminal is make known, thereby eliminating conventional tasks such as location and mobility management tasks and allowing wireless terminals to be low power.
Abstract: A network access scheme enhances channel utilization under the ALOHA protocol by making use of the FM capture effect. The resulting network access scheme allows a transmitter to transmit a message simultaneously with other transmitters to a receiver without the need for retransmission when the message reaches the receiver with sufficient strength over the strengths of the other transmissions. In one embodiment, the network access scheme is applied to a wireless data network, which includes support to a two-way paging application. Another network access scheme combines the high channel utilization of the carrier sensing multi-access (CSMA) protocol with the FM capture effect to provide even higher expected channel utilization. The resulting network access scheme uses a channel access protocol ("CSMA/AT") which provides an adaptive threshold. An RF transmitter determines, using the adaptive threshold, whether or not to transmit its message.
Abstract: A method for selecting a symbol using an M-key keyboard in a personal information device (PID) divides the M keys into a first key group and a second key group. Each symbol to be recognized from the input key-strokes on the keyboard is assigned a unique two-keystroke sequence in which the first key and the second key of that two-keystroke sequence are selected from different key groups. When receiving keystrokes from the keyboard, two-keystroke sequences received from the keyboard are matched to the symbol assignments to derive which symbol is selected. This method is applicable not only for selecting letters from a European alphabet, such as the English or the Cyrillic alphabets, this method is applicable to selecting from a phonetic alphabet, such as the Pin-Yin system for Chinese characters and other phonetic systems in the Korean and Japanese languages as well.
February 23, 1996
Date of Patent:
August 26, 1997
General Wireless Communications, Inc.
Weijia Wang, Chuan David Ai, Michael M. Y. Tsai