Telefonaktiebolaget Lm Ericsson (publ)

Nikos Katinakis

Donald Joong

Akbar Rahman

Alan Eric Sicher

Ming Ma

A system and method of transferring data to and from a mobile station (MS) in a cellular telecommunications network. When the MS originates a data transmission, the MS simultaneously seizes additional voice channels or control channels from the serving cell or adjacent cells, fills time slots with data packets, and asynchronously transmits the data packets over the plurality of channels in order to increase the data transfer rate. For data calls terminating at the MS, the serving mobile switching center (MSC) reserves a plurality of channels having sufficient signal strength to maintain a connection with the destination MS. The MSC informs the involved base stations that an asynchronous transmission is to be made to the MS. The MSC then assembles the data packets and starts transmission through the involved base stations to the MS over the reserved channels. The MS assembles the packets in numerical order and delevers the data to the user.

Asynchronous transfer on the cellular radio link

Procedures are disclosed for supporting roaming subscriber mobile station access to stored subscriber data messages. In one aspect, a received subscriber data message is routed for storage and subsequent forwarding/retrieval, not to a &ldquo;home&rdquo; message center, but instead to a message center either optimally positioned with respect to a current known location of the subscriber mobile station or associated with an initially receiving mobile switching center. In another aspect, a mailbox established for a given subscriber mobile station in the home message center is transferred (perhaps on a periodic basis) for storage in a local mailbox of a proximate message center within a cellular telephone network where the subscriber is currently roaming. In either case, the storing message center thereafter performs any requisite operations needed to facilitate message forwarding to or retrieval by the addressee subscriber mobile station.

Distributed data storage and delivery in a cellular telephone network

A number of different mechanisms are proposed for effectuating the delivery of digital data messages to mobile stations which have currently selected an analog control channel. In one method, a signal is sent to the mobile station instructing it to make a server reselection and choose the best available digital control channel. Once the reselection is accomplished, the digital data message is delivered in a conventional manner using the digital control channel. In another method, the digital data message is reformatted for analog delivery, and the reformatted message sent over either the analog control channel or a selected analog voice channel. In yet another method, a call connection is made with the mobile station over a voice channel, and a synthesized audible message corresponding to the digital data message is transmitted over the voice channel after the subscriber answers the call. In instances where message delivery over the control channel is interrupted due to mobile station roaming, a forced re-registration occurs following the new server reselection, thus triggering continued message delivery over the new control channel.

Delivery of subscriber digital data messages in a dual mode cellular

A system and method of simultaneously conducting a data transfer and a voice call between a mobile station and a radio telecommunications network having a mobile switching center (MSC) which serves the mobile station. A first embodiment includes a landline digital simultaneous voice and data (DSVD) modem associated with the mobile station which generates DSVD source signal and line negotiation protocols. The DSVD source signal and line negotiation protocols are encapsulated into circuit mode Radio Link Protocol (RLP) signals and transmitted to the MSC. An interworking function (IWF) associated with the MSC translates the circuit mode RLP signals into signals in a landline telecommunications protocol. In another embodiment, the voice call is carried over the air interface from the mobile station to the network in one timeslot, and the data transfer is carried in at least one additional timeslot on the same voice channel. In other embodiments, two voice channels may be allocated to the same mobile station. The voice call to a first party is carried from the mobile station to the network on one voice channel, and the data transfer to the first or a second party is carried on the second voice channel. The MSC hands off the two voice channels together, but releases them individually when either the voice call or the data transfer is completed.

Cellular simultaneous voice and data including digital simultaneous

In a TDMA/TDD communication system and method, communication throughput is increased by allowing direct duplex communication between the mobile stations that are within close proximity of each other. The system and method determines the range of the mobile stations from each other. Based on the range, the communication units may communicate with each other in one of either direct mode or indirect mode. If an in-range condition is determined, the mobile stations engage in direct duplex communication with each other. Otherwise, they communicate with each other in the indirect mode.

Method and apparatus for direct communication between mobile stations

An emergency call handling system and method for a cellular telecommunications system. The emergency call handling system is provided with at least one subscriber terminal which upon failure to seize a voice connection to an emergency center for an emergency call, transfers data messages over the digital control channel to the emergency center advising it that the user of this one subscriber terminal has an emergency situation. Advantage is found with the present invention in that in times of radio voice channel and/or network traffic congestion resulting in call set up failure, the information relating to a user emergency can be forwarded as data messages to the emergency center.

Growing community of inventors

Stockholm, Sweden

Nikos Katinakis