Systems and methods for wireless communications via satellite

1. An apparatus for transmitting a voice call via satellite from a mobile station to a destination station, comprising:

a first data channel, the first data channel comprising an integrated services digital network connection;

a second data channel, the second data channel comprising a mobile packet data system connection;

a mobile terminal adapter that receives a voice call from a mobile station and processes the received voice call for transmission over the first data channel and the second data channel; and

a first voice processing unit that inserts additional bits into the voice data when transmitting the voice data from the mobile terminal adapter to the satellite,

wherein the mobile terminal adapter (1) divides the voice call into voice data and signaling data, the voice data being transmitted to and from the satellite using the first data channel, and the signaling data being transmitted to and from the satellite using the second data channel, and (2) activates the first data channel as needed for voice data transmission and deactivates the voice channel when not required for voice data transmission, and

the first voice processing unit inserts an additional number of bits into the voice data to increase the data transmission rate of the voice data to one of 8 kbps or 16 kbps.

2. The apparatus of claim 1 , further comprising a unit which charges for usage of the first data channel according to the duration of connect time.

3. The apparatus of claim 1 , further comprising a unit which charges for usage of the second data channel according to the amount of transmitted data.

4. The apparatus of claim 1 , wherein the first data channel comprises a time division multiplexing channel.

5. The apparatus of claim 4 , wherein the voice data is transmitted in at least one time slot of the time division multiplexing channel.

6. The apparatus of claim 5 , wherein at least one remaining time slot of the time division multiplexing channel is used to transmit at least one additional voice call.

7. The apparatus of claim 1 , further comprising a second voice processing unit that removes the inserted additional bits from the voice data when transmitting the voice data from the satellite to the destination station.

8. The apparatus of claim 1 , further comprising a voice multiplexer which assembles the voice data into time slots in a frame of data to be transmitted over the first data channel.

9. The apparatus of claim 8 , further comprising a voice demultiplexer which extracts the voice data arriving in time slots in a frame of data over the first data channel into a stream of data.

10. A method for transmitting a voice call from a mobile station to a satellite, comprising:

separating voice call data received from a mobile station into voice data and signaling data;

accessing a first data channel, the first data channel comprising an integrated services digital network connection, and a second data channel, the second data channel comprising a mobile packet data system connection, for separately transmitting the voice data and the signaling data to the satellite, the second data channel being always activated for the transmission of data and the first data channel being selectively activated based on a determination that voice data is available to be transmitted;

activating the first data channel only when the voice data is available to be transmitted;

inserting additional bits into the voice data when transmitting the voice data from the mobile station to the satellite, the additional bits being added to increase the data transmission rate of the voice data to one of 8 kbps or 16 kbps:

transmitting the voice data across the first data channel;

transmitting the signaling data across the second data channel; and

deactivating the first channel on completion of the transmission of the voice data.