Abstract: System capable of giving a sense of unity or solidarity to a plurality of users sharing information is provided. Each of a plurality of client terminals includes a position information acquiring means. A management server updates user position information stored in a user database based on present position information of the respective client terminals. The management server reads a plurality of items of user position information contained in a predetermined range and a plurality of items of user information associated with the user position information contained in the predetermined range from the user database on the basis of the predetermined range of the map information read from a map database, and transmits them to the client terminals. The client terminal displays the items of user information at respective positions corresponding to the items of user position information on the map information in the predetermined range received from the management server.

Abstract: A backlighting system is placed in an elongated interior space within a personal digital assistant (PDA) which normally houses a stylus used to touch a liquid crystal display (LCD) touch and display screen. A backlight driver circuit is constructed on a printed circuit board (PCB) which fits within the elongated space, and an on-off switch extends from the PCB to an exterior hole formed in the PDA housing. An on-time control turns off power to the backlight driver circuit after a predetermined time has elapsed following activation of the on-off switch, and a dimming control controls the amount of energy delivered to the electroluminescent film. A torroidal switching transformer of a high voltage power supply minimizes noise, and a switching controller switches adjustable width current pulses through the transformer to regulate the high voltage level. A flyback circuit captures and uses a portion of the back EMF energy created when the current pulses are switched through the switching transformer.

Abstract: A wireless data communication system includes a code encoder for transforming pulse code modulated data into a simple code having an alphabet with at least one spare symbol into which a delimiter symbol is introduced, which code is transmitted to a receiver including a matched filter arrangement and a code maximum decision arrangement for decoding the transmitted code signal and for detecting the delimiter symbol.

Abstract: A communicator station wirelessly transmits frames to and receives frames from a least one additional communicator in a Group in accordance with a MAC protocol. One of the communicators functions as a hub and the remaining communicators function as remotes. The hub sends control information to the hubs to establish repeating communication cycles, each of which has intervals during which the hub and the remotes transmit and receive frames. The intervals allow the hub and the remotes to anticipate transmitting and receiving frames, thereby allowing the remotes to power off their receivers and transmitters to achieve a considerable savings in power consumption without degrading communications. Other improved features include adjusting the intervals and the durations of transmission opportunities in the communication cycle to obtain the beneficial aspects of TDMA and PRMA for LAN-like communication without also incurring most of the undesirable aspects of such MAC techniques.

Abstract: A bridging apparatus provides the capability of transparently and unambiguously communicating LAN packets between two separate LAN segments which have nodes with duplicate IDs. A communicator connected to each LAN segment includes a controller which aliases the source identification (SID) of remotely originated or sourced LAN packets with an unused ID which is an alias (AID) before sending the LAN packet with the AID as its SID on the local LAN segment. The reverse occurs in response to locally sourced LAN packets containing the AID as the DID. The ID of the remote node which correlates to the AID is substituted as the DID before the LAN packet is transmitted to the remote LAN segment. By aliasing in this manner LAN packets are communicated by use of the AIDs between the nodes having the duplicate IDs on the two LAN segments without changing the LAN protocol. Each communicator preferably includes a transmitter and receiver by which to communicate bridge packets between communicators.