Abstract: Circuits and methods for detecting the presence of a leading-edge phase-cut dimmer. The dimmer detector comprises an edge detector, a pulse stretcher and a filter. The edge detector detects whether an input signal has a rapidly rising edge and generates an output signal pulse if a rapidly rising edge is detected. If the edge detector outputs a signal pulse, the pulse stretcher generates a stretched pulse having a duration that is longer than the signal pulse received from the edge detector. The filter produces a dimmer detect signal that indicates whether a leading-edge phase-cut dimmer is detected. If the pulse stretcher output signal comprises at least a predetermined number of stretched pulses within a predetermined amount of time, the dimmer signal signals the presence of a leading-edge phase-cut dimmer.

Abstract: Circuits and methods for detecting the presence of a leading-edge phase-cut dimmer. The dimmer detector comprises an edge detector, a pulse stretcher and a filter. The edge detector detects whether an input signal has a rapidly rising edge and generates an output signal pulse if a rapidly rising edge is detected. If the edge detector outputs a signal pulse, the pulse stretcher generates a stretched pulse having a duration that is longer than the signal pulse received from the edge detector. The filter produces a dimmer detect signal that indicates whether a leading-edge phase-cut dimmer is detected. If the pulse stretcher output signal comprises at least a predetermined number of stretched pulses within a predetermined amount of time, the dimmer signal signals the presence of a leading-edge phase-cut dimmer.

Abstract: Circuits and methods for detecting the presence of a leading-edge phase-cut dimmer. The dimmer detector comprises an edge detector, a pulse stretcher and a filter. The edge detector detects whether an input signal has a rapidly rising edge and generates an output signal pulse if a rapidly rising edge is detected. If the edge detector outputs a signal pulse, the pulse stretcher generates a stretched pulse having a duration that is longer than the signal pulse received from the edge detector. The filter produces a dimmer detect signal that indicates whether a leading-edge phase-cut dimmer is detected. If the pulse stretcher output signal comprises at least a predetermined number of stretched pulses within a predetermined amount of time, the dimmer signal signals the presence of a leading-edge phase-cut dimmer.

Abstract: A communications system includes a first PTT network, and a second PTT network having a plurality of interoperability gateways. A method for routing a PTT call terminated at the second PTT network includes receiving a PTT call request from the first PTT network, the PTT call request identifying a target subscriber unit on the second PTT network and forwarding the PTT call request to a first interoperability gateway. If the target is located in a region served by a second PTT interoperability gateway, then a redirect message, including an identifier of the second PTT interoperability gateway, is received and the PTT call request is redirected to the second PTT interoperability gateway. An identifier of the target and an identifier of the second PTT interoperability gateway are stored in a cache for directing subsequent PTT calls to the same target to the corresponding second interoperability gateway.

Abstract: A communications system includes a first PTT network, and a second PTT network having a plurality of interoperability gateways. A method for efficiently selecting an interoperability gateway for PTT calls terminated at the second PTT network includes receiving a PTT call request from the first PTT network, the PTT call request identifying a target subscriber unit on the second PTT network and forwarding the PTT call request to a first interoperability gateway. Notification is received if the request has succeeded, and the notification includes an identification of the target and a second interoperability gateway. This information is stored in cache for directing subsequent PTT calls to the same target to the corresponding second interoperability gateway. In one embodiment, the first PTT network is an iDEN network and the second PTT network is a HPPTT network and the PTT call is a HPPTT call.

Abstract: A dispatch call request is received from a calling party to make an inter-urban dispatch call to a called party over a telecommunications network. A determination is first made as to whether the calling party is restricted from making inter-urban calls and, if so, a determination is then made as to whether the called party is an unrestricted access subscriber. In one embodiment, the dispatch call will be connected to the called party when the calling party is restricted from making inter-urban calls and the called party is an unrestricted access subscriber.

Abstract: Methods and systems for IMEI registration are provided. In accordance with exemplary embodiments of the present invention, when an IMEI registration fails due to a network failure, the mobile station implements a back-off algorithm for future IMEI registration attempts. Specifically, the present invention provides a back-off algorithm which determines a different amount of time for the time period between each unsuccessful IMEI registration.

Abstract: Methods and systems for IMEI registration are provided. In accordance with exemplary embodiments of the present invention, when an IMEI registration fails due to a network failure, the mobile station implements a back-off algorithm for future IMEI registration attempts. Specifically, the present invention provides a back-off algorithm which determines a different amount of time for the time period between each unsuccessful IMEI registration.

Abstract: A system and method for providing an iDEN user the ability to roam onto a peer iDEN Network. An iGW supports the passing of Dispatch registration information back to the users home network. The iGW will also support and assist in setting up Dispatch Calls between the two iDEN Networks, and vice versa. Exemplary embodiments of the present invention also support roaming from another technology that supports Dispatch Services (i.e., CDMA QChat and GSM PoC), where if a iDEN subscriber with a dual mode phone (i.e., iDEN & GSM), was to roam onto another carrier with a different technology but with Dispatch capabilities, the iDEN subscriber is able to register on the roaming carrier's network. The iGW is capable of receiving the registration update from the roaming network and updating the iDEN Network with the location of the iDEN Subscriber. If another iDEN Subscriber attempts a dispatch call to the roaming iDEN Subscriber, the iGW facilitates the Dispatch Call.

Abstract: A system and method for providing subscriber presence information in a dispatch network is disclosed. In an embodiment of the method, presence subscription information related to a dispatch network subscriber is provided to a home location register. A presence message is provided to a presence server related to the subscription information. A presence status is provided to a party by the presence server. In an embodiment of the system, a home location register stores a subscriber presence table. The presence table includes presence subscription information related to a dispatch network subscriber. A dispatch application processor (DAP) is coupled to the home location register and the DAP retrieves the presence subscription information for a subscriber registered in the DAP. The DAP provides a presence message to the presence server and the presence server provides a presence status to a communications medium.

Abstract: A wireless communication system including dispatch call controllers, signaling gateways, base stations, a first network coupling the dispatch call controllers to the signaling gateways, and a second network coupling the signaling gateways to the base stations. The signaling gateways serve as intermediaries between dispatch call controllers and base stations by translating messages received from dispatch call controllers intended for the base stations from the protocol used in the first communications network to the protocol used in the second communications network, and translating messages received from base stations intended for dispatch call controllers from the protocol used in the second communications network to the protocol used in the first communications network. The system may be configured such that each dispatch call controller has individual logical links to each of the signaling gateways, and each signaling gateway has logical links to a distinct subset of the base stations.