Abstract: Data transfer efficiencies of a frequency division and/or time division multiple access (FDMA/TDMA) communication methods are improved over prior art methods by communicating over a channel group of a comunication system. A central station transmits to a number of terminals over a forward channel, and transmissions by at least one of the terminals to the central station occur over a return channel of the channel group. The improved methods include the step of transmitting by the at least one of the plurality of terminals at least one superframe to the central station at one of a plurality of data rates over one of a plurality of return channels using a corresponding one of a plurality of data frames having lengths responsive to the one of the plurality of data rates. The methods may also include the step of formatting said transmission superframe comprising a plurality of frames by removing network management information which is not time critical from substantially all of the plurality of frames.