Patent attributes
A communications terminal comprises an encoder configured to encode a digital data signal to generate an encoded signal, a scrambler configured to scramble the encoded signal based on a scrambling signature, and a modulator configured to modulate resulting data frames for transmission via a random access communications channel. Each frame comprises a data payload, including a block of the scrambled signal, and a header, including a start of frame (SOF) sequence associated with the scrambling signature. Use of the SOF sequence for each frame provides a synchronization reference and serves to designate the associated scrambling signature for decoding the respective data payload. Use of the SOF sequence for each frame further serves to distinguish between the data frame and data frame(s) originating from further communications terminal(s), transmitted via a common time slot of the channel, for which different scrambling signature(s) were used to scramble respective encoded signal(s) thereof.