Abstract: A system and method for multiplexing data streams in order to optimize network resources for Push-to-talk-over-Cellular (PoC) systems. One or more servers interface to the wireless communications network to perform advanced voice services for one or more mobile units therein, which include a Push-to-Talk-over-Cellular (PoC) call session. Both the servers and the mobile units that use the advanced voice services communicate with each other using control messages within the wireless communications network, and at least one of the servers switches media streams comprised of voice messages for the advanced voice services between the mobile units across the wireless communications network. At least one of the mobile units is a participant in a plurality of PoC call sessions concurrently, and at least the media streams for each of the plurality of the PoC call sessions are multiplexed into a single path.

Abstract: An embodiment method includes initiating, by one or more servers of a push-to-talk (PTT) platform, a PTT call session in response to a PTT call session initiation request from a first client device, receiving, by the one or more servers, a first estimated modulation and coding scheme (MCS) from the first client device, and receiving, by the one or more servers, a first transmission in accordance with an initial media encoding scheme (MES) from the first client device during an initial volley. The method further includes transmitting, by the one or more servers, instructions to the first client device to use a first MES different than the initial MES for a second transmission during a subsequent volley.

Abstract: A system and method for relay-mode and direct-mode operations for Push-to-talk-over-Cellular (PoC) using WiFi technologies. One or more servers interface to a wireless communications network to perform advanced voice services for mobile units therein, wherein the advanced voice services include an instant two-way half-duplex voice call within a group of the mobile units comprising a PoC call session. Both the servers and the mobile units that use the advanced group services communicate with each other using control messages within the wireless communications network. At least one of the servers switches voice messages for the advanced group services between the mobile units across the wireless communications network. At least one of the servers manages the call session by acting as an arbitrator for the call session and by controlling the sending of the control messages and the voice messages to and from the mobile units.

Abstract: A method of operating a client device in a Push-to-talk (PTT) network includes monitoring, by the client device, radio conditions of the PTT network, and generating a radio condition parameter by the client device. The method also includes calculating, by the client device, an estimate of Channel Quality Indicator (CQI) using the radio condition parameter, and determining, by the client device, a first Modulation and Coding Scheme (MCS) in accordance with the estimate of CQI.

Abstract: A system and method for providing advanced voice services in a wireless communications network. The system also interfaces to an Internet Protocol (IP) network to perform the advanced voice services for mobile units in the IP network and includes a protection mechanism against Voice-over-IP (VoiP) Denial-of-Service (DoS) attacks utilizing Advanced Group Services (AGS).

Abstract: A system and method for optimizing large group calling using unicast and multicast transport bearers for Push-to-talk-over-Cellular (PoC). One or more servers interface to a wireless communications network to perform advanced voice services for mobile units therein, including the PoC call session. The servers and mobile units communicate with each other using control messages, and the servers switch voice messages between mobile units. At least one of the servers manages the PoC call session by acting as an arbitrator, and controls sending of control messages and voice messages to and from mobile units. The server performs unicast and multicast delivery of control messages and voice messages to and from mobile units, thereby enabling large group calling involving a large number of participants with optimized use of network and server resources.

Abstract: A system and method to leverage Web Real-Time Communication (WebRTC) for implementing Push-to-Talk (PTT) solutions. One or more servers interface to a communications network to perform advanced voice services for one or more wireless or wired user devices, wherein the advanced voice services include a two-way half-duplex voice call within a group of the user devices comprising a PTT call session. At least one of the user devices communicates with at least one of the servers during the PTT call session using a WebRTC connection, and at least the media streams for the PTT call session are transmitted between the server and the user device using the WebRTC connection.

Abstract: An architecture framework to realize Push-to-X services using cloud-based storage services. Push-to-X messages are transmitted between mobile units by messaging servers. The Push-to-X message may include a short text message contained wholly within the Push-to-X message, or the Push-to-X message may include one or more attachments that comprise multimedia contents, files, or location information, which are stored on storage servers, wherein the Push-to-X message identifies a location for retrieving the attachments from the storage servers. The Push-to-X messages may be sent to a single mobile unit identified by a Mobile Directory Number (MDN) or a group of mobile units identified by a list of MDNs or a Uniform Resource Identifier (URI).

Abstract: A Push-to-Talk-over Cellular (PoC) implementation for use in a wireless communications network, wherein one or more servers interface to the wireless communications network to perform the PoC call sessions. Both the servers and the mobile units that use the PoC call sessions communicate with each other using SIP/IP (Session Initiation Protocol/Internet Protocol) control messages within the wireless communications network, and one or more of the servers switches RTP/IP (Realtime Transport Protocol/Internet Protocol), RTCP/IP (Realtime Transport Control Protocol/Internet Protocol), or MBCP/IP (Media Burst Control Protocol/Internet Protocol) voice packets for the PoC call sessions between the mobile units across the wireless communications network.

Abstract: A system and method for providing radio access network (RAN) aware service delivery for Push-to-talk-over-Cellular (PoC) networks, wherein at least one of the servers performs an presence delivery method that reduces presence notifications delivered to the mobile units participating in communications services. The effective presence delivery method may comprise: throttling the delivery of the presence notifications; avoiding simultaneous dispatch of the presence notifications to multiple watchers located in the same cell or group of cells of the wireless communications network; or the server delaying sending the presence notifications for a mobile unit until the mobile unit triggers the server.

Abstract: A system and method to leverage Web Real-Time Communication (WebRTC) for implementing Push-to-Talk (PTT) solutions. One or more servers interface to a communications network to perform advanced voice services for one or more wireless or wired user devices, wherein the advanced voice services include a two-way half-duplex voice call within a group of the user devices comprising a PTT call session. At least one of the user devices communicates with at least one of the servers during the PTT call session using a WebRTC connection, and at least the media streams for the PTT call session are transmitted between the server and the user device using the WebRTC connection.

Abstract: A network-to-network interface (NNI) gateway system for inter-communication between a Push-to-talk-over-Cellular (POC) system in a first wireless network and an Integrated Digital Enhanced Network (iDEN) system in a second wireless network. The POC system performs a POC call session for POC mobile units in the first wireless network. The iDEN system performs a Push-to-Talk (PTT) call session for iDEN subscriber units in the second wireless network. The gateway system bridges the iDEN system to the POC system, such that the POC system is exposed to the iDEN system as an emulated iDEN system, the iDEN system is exposed to the POC system as an emulated POC system, and calls are placed across the first and second wireless networks between the POC mobile units and iDEN subscriber units.

Abstract: An architecture framework to realize Push-to-X services using cloud-based storage services. Push-to-X messages are transmitted between mobile units by messaging servers. The Push-to-X message may include a short text message contained wholly within the Push-to-X message, or the Push-to-X message may include one or more attachments that comprise multimedia contents, files, or location information, which are stored on storage servers, wherein the Push-to-X message identifies a location for retrieving the attachments from the storage servers. The Push-to-X messages may be sent to a single mobile unit identified by a Mobile Directory Number (MDN) or a group of mobile units identified by a list of MDNs or a Uniform Resource Identifier (URI).

Abstract: A system and method for multiplexing data streams in order to optimize network resources for Push-to-talk-over-Cellular (PoC) systems. One or more servers interface to the wireless communications network to perform advanced voice services for one or more mobile units therein, which include a Push-to-Talk-over-Cellular (PoC) call session. Both the servers and the mobile units that use the advanced voice services communicate with each other using control messages within the wireless communications network, and at least one of the servers switches media streams comprised of voice messages for the advanced voice services between the mobile units across the wireless communications network. At least one of the mobile units is a participant in a plurality of PoC call sessions concurrently, and at least the media streams for each of the plurality of the PoC call sessions are multiplexed into a single path.

Abstract: A network-to-network interface (NNI) gateway for inter-communication between a Push-to-Talk-over-Cellular (PoC) system in a first wireless network and a Land Mobile Radio (LMR) system in a second wireless network. The PoC system performs a PoC call session for PoC mobile units in the first wireless network. The LMR system performs a Push-to-Talk (PTT) call session for LMR subscriber units in the second wireless network. Both the PoC and PIT call sessions comprise an instant two-way half-duplex voice call within a group of the PoC mobile units and/or LMR subscriber units. The gateway bridges the LMR system to the PoC system, such that the PoC system is exposed to the LMR system as an emulated LMR system, the LMR system is exposed to the PoC system as an emulated PoC system, and calls are placed across the first and second wireless networks between the PoC mobile units and LMR subscriber units.

Abstract: A system and method for relay-mode and direct-mode operations for Push-to-talk-over-Cellular (PoC) using WiFi technologies. One or more servers interface to a wireless communications network to perform advanced voice services for mobile units therein, wherein the advanced voice services include an instant two-way half-duplex voice call within a group of the mobile units comprising a PoC call session. Both the servers and the mobile units that use the advanced group services communicate with each other using control messages within the wireless communications network. At least one of the servers switches voice messages for the advanced group services between the mobile units across the wireless communications network. At least one of the servers manages the call session by acting as an arbitrator for the call session and by controlling the sending of the control messages and the voice messages to and from the mobile units.

Abstract: An embodiment method includes initiating, by one or more servers of a push-to-talk (PTT) platform, a PTT call session in response to a PTT call session initiation request from a first client device, receiving, by the one or more servers, a first estimated modulation and coding scheme (MCS) from the first client device, and receiving, by the one or more servers, a first transmission in accordance with an initial media encoding scheme (MES) from the first client device during an initial volley. The method further includes transmitting, by the one or more servers, instructions to the first client device to use a first MES different than the initial MES for a second transmission during a subsequent volley.

Abstract: A method of operating a client device in a Push-to-talk (PTT) network includes monitoring, by the client device, radio conditions of the PTT network, and generating a radio condition parameter by the client device. The method also includes calculating, by the client device, an estimate of Channel Quality Indicator (CQI) using the radio condition parameter, and determining, by the client device, a first Modulation and Coding Scheme (MCS) in accordance with the estimate of CQI.

Abstract: A system and method for supporting multiple simultaneous connections to different access networks for use in Push-to-talk-over-Cellular (PoC). One or more servers interface to a plurality of wireless communications networks to perform advanced voice services for mobile units therein, including the PoC call session. The servers and mobile units communicate with each other using control messages, and the servers switch voice frames between the mobile units. At least one of the servers manages the PoC call session by acting as an arbitrator, and controls the sending of the control messages and the voice frames to and from the mobile units. At least one of the mobile units and at least one of the servers use multiple simultaneous connections to the plurality of wireless communications networks to communicate with each other.

Abstract: A system and method for optimizing large group calling using unicast and multicast transport bearers for Push-to-talk-over-Cellular (PoC). One or more servers interface to a wireless communications network to perform advanced voice services for mobile units therein, including the PoC call session. The servers and mobile units communicate with each other using control messages, and the servers switch voice messages between mobile units. At least one of the servers manages the PoC call session by acting as an arbitrator, and controls sending of control messages and voice messages to and from mobile units. The server performs unicast and multicast delivery of control messages and voice messages to and from mobile units, thereby enabling large group calling involving a large number of participants with optimized use of network and server resources.