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.