Abstract: A wireless local area network system (100) supporting mobile radio telephony reduces the time to complete an authenticated handover from one access point (104) to another (108) by a mobile station (102) by performing some of the steps normally performed upon leaving one access point while still associated with that access point. More particularly, the mobile station causes a cryptographic key (204) to be preestablished (212) for use when handing over to a new access point. The cryptographic key is derived at the mobile station, and is also derived in the WLAN infrastructure and stored until the mobile station initiates a handover.

Abstract: A digital network based communications system that establishes communications sessions to communicate via a simulated circuit-switch environment. Exemplary embodiments communicate between a first communications station (104) and a second communications station (106) using Voice over Internet Protocol (VOIP) techniques. Calls are setup (700), maintained and torn down (800) using Session Initiation Protocol and Session Description Protocol messages. Call modes are able to be changed between duplex and simplex without disconnection. Duplex calls are also able to be interrupted with a request for a simplex call. A receiver (104) engaged in a duplex call can receive a request for a simplex call, accept the simplex call or send a response message, and then resume the duplex call, all while maintaining the duplex call data communications session.

Abstract: A wireless station (114) is within range of more than one access point (120, 124) transmitting on the same channel. The wireless station is associated with one access point and not the other. Consequently the wireless station may receive undesired beacons (304) and desired beacons (302) on the channel. To optimize power save operation the wireless station arbitrates between a scan and shut down scanning procedure (708) and a timed window channel scanning procedure (724), depending on whether the desired beacon is the first received beacon upon waking up from a low power state at a target beacon time.

Abstract: The invention provides a method and apparatus for achieving timing synchronization during signal acquisition and for achieving frequency synchronization in a digital communication receiver after signal acquisition. The invention operates by performing multiple correlations of a received signal, each correlation performed over an symbol interval and correlating the received signal in the symbol interval with a sinusoid of an expected frequency. The correlations are combined to determine a peak and energy, and if the peak to energy ratio is above a threshold, the symbol timing and frequency offset is estimated.

Abstract: A multi-mode mobile communication device capable of communicating with more than one mobile communication system simultaneously has a timer (400) for arbitrating between transmit events of two communication systems. The mobile communication device assigns a priority to each of the two communication systems, and when a transmit event conflict arises, it is resolved in favor of the system having the higher priority. The timer includes a delta timer (426) for timing the duration of transmit events. If the mobile communication device is engaged in a transmit event in one system, and a transmit event arises in the second system, the mobile communication device checks the delta timer. If the timer is not zeroed, the mobile communication device then checks priority of the events, and transmits whichever event has priority.

Abstract: Human hearing perceives loudness based on critical bands corresponding to different frequency ranges. As a sound's frequency spectrum increases beyond a critical band into a previously unexcited critical band, the perception is that the sound has increased in loudness. To take advantage of this principle, a filter is applied to a speech signal so as to expand the formant bandwidths of formants in the speech sample.

Abstract: A populated printed wiring board (PWB) (100) and method of manufacturing the populated PWB are taught. The populated PWB is manufactured by fabricating a PWB (102, 402) with exposed copper pads (302), coating the copper pads with an organic solderability preservative (OSP) (404), depositing a solder paste that includes lead-free solder on the OSP covered copper pads (406), placing components (408) and heating the PWB above a liquidous temperature of the lead-free solder in an air atmosphere (410). The process allows very close spacing of components and component leads while forming reliable solder joints to components that are mechanically stressed and components that have non-negligible planarity or coplanarity tolerances.

Abstract: A method of mixed mode communication in a wireless mobile communication system allows a first user to initially communicate with a second user using a first communication mode (108), such as a voice calling mode. During the use of the first communication mode, the users decide (110) to use a second communication mode to facilitate a different form of communication, such as an image transfer. The communication device then establishes a second communication link (104), and a second mode of communication is then engaged in (118). Upon finishing the second communication mode, (120), the first communication mode remains, or is reestablished (124).

Abstract: A transmitter (200) has a compression detector for sensing the level of compression (110) in a signal that is being transmitted. The transmitter also has a radio frequency power amplifier (RFPA) (414) that is supplied by a supply modulator (426). The supply modulator provides a dynamic supply bias to the RFPA to maintain a desired amount of compression in the signal being transmitted. The supply modulator is responsive to a modulation signal (207) created by substantially following the envelope (214) of the signal to be transmitted (212). However, various signal and operational conditions can occur which cause the compression level to deviate (506) from the desired level. To maintain the desired compression level, the compression detector provides an output that is used to adjust the modulation signal from following the envelope of the signal to be transmitted in an unadjusted manner.

Abstract: A mobile communication device (214) in a communication system (200) initiates a call over the fixed equipment network of the communication system to another mobile communication device (216). If the two mobile communication devices are within sufficient proximity to each other, they may switch to a direct mode of communication. (318). The direct mode and network mode of communication are in different frequency bands using different air interface protocols.

Abstract: A peripheral component (104) is attached to a portable electronic device (102), and indicates an option class of the peripheral component by use of an option select circuit. The option select circuit causes an interrupt to be generated in the portable electronic device, which then determines the option class by changing the logic levels of various option select lines. If an inversion of the logic state of one of the option select lines is detected, then the portable electronic device knows an option select circuit is present, and determines the option class of the peripheral component accordingly.

Abstract: A mobile communication device (200) has a software architecture (302) that includes a closed operating environment (306). The closed operating environment is inaccessible to the user of the mobile communication device, and it includes software for implementing a reporting function designed to collect certain information from within the mobile communication device, and to transmit it to an entity outside the mobile communication device, such as a server (310).

Abstract: In a CDMA wireless communication system (200) a dispatch call can be established between two CDMA mobile stations (202, 226), or between other mobile stations and the CDMA mobile station, or between a CDMA mobile station and a computer (236) located outside of the wireless system. To reduce the delay normally association with call set up in a CDMA system, a dispatch processing network (128, 144) is provided in addition to a telephony switch (118). Dispatch calls and call set up requests are routed to the dispatch processing network from the radio access network (110) which includes base stations (204, 206). Once a dispatch call request is made, while the dispatch processing network begins setting up a traffic channel for the originating mobile communication device, the target is also paged, and upon responding, set up on a traffic channel. The concurrence of establishing radio links with the target and originating communication devices substantially reduces dispatch call set up time.

Abstract: A touch screen assembly includes a first outer layer (102) and a second outer layer (110) separated by a separator layer (118). The first and second outer layers are transparent, and the separator layer has openings (120) at button locations where buttons will be defined. On each of the outer layers is a layer of transparent conductor (104, 112). On the first outer layer the transparent conductor is in the form of a contiguous trace or path. The touch screen assembly is placed on a display element (203) and images displayed on the display element can be seen through the touch screen assembly. Images such as characters are displayed at button locations, and when a user presses on one of the images the conductive layers on the first and second outer layers of the touch screen assembly come into contact.

Abstract: A multi-configuration electronic device has two body portions (102, 104) that move with respect to each other, and a single display module (108). As the device is reconfigured from an open position (100) to a closed position (400), the display module rotates so that it is viewable in either of those positions. The rotation may be performed by use of a belt (802), gear and axle (1000), or a combination of belt and gear and axle (1300). The display may rotate horizontally or vertically.

Abstract: A radio (100) provides multiple audio modes of operation, such as a cellular and dispatch modes. Illumination devices (108, 110) are located near the radio's audio sources (104, 106) and become activated to indicate to the user which mode of operation is present.

Abstract: A voice channel data processor 207 and corresponding method 600 operable in a wireless communications unit's 200 receiver and transmitter to facilitate data transmission on a voice channel includes an encoder 301 for encoding data traffic as a transmit voice frame having a predetermined vocoder parameter and inserting the transmit voice frame into a stream of transmit voice frames with voice traffic and further includes a decoder 303 for parsing a stream of received voice frames to obtain a vocoder parameter for each, comparing the vocoder parameter for each received frame to the predetermined vocoder parameter, routing the received voice frame for processing as data traffic when the comparison is favorable, and otherwise routing the received voice frame for processing as voice traffic.

Abstract: A first housing member (102) has a catch member (110) that engages a catch feature (302) on an inside surface of a second housing member (104) when the housing members are assembled together. A release window (117) is formed in the side of the second housing member to facilitate unlatching of the catch member from the catch feature. Alternatively, a latch release member (114) may be disposed in the release window so as to allow unlatching without the use of a tool. Additionally, the complaint covering may be formed so as to provide a water seal between the housing members, via sealing ridge (802) and a sealing groove (902).

Abstract: A mobile communication device (102) receives information in a broadcast control channel (108) including a page message (108). The mobile communication device measures certain parameters (210) of the control channel, such as received signal strength, channel quality, and the present automatic gain setting. These parameters are scored and weighted (300) to produce a signal quality metric (314) to determine the duration of time the mobile communication device can remain in a low power state to conserve battery charge before checking for page alert message in the broadcast control channel next.

Abstract: In time divisioned, multi-frequency communication air interfaces it is common for a control channel to be defined on a first frequency while traffic channels are carried on other frequencies. A mobile communication device maintains the automatic gain control (AGC) settings for a first frequency while engaged on a second frequency by adjusting the AGC of the first frequency to correspond with changes in the AGC setting for the second frequency before attempting to access the first frequency again. Since, in the communication system, the two signals are transmitted from the same point, the changes in signal level will typically be similar enough that the mobile communication device will not have to perform a new AGC determination when switching back to the first frequency.