Combined use of PN sequence for data scrambling and frame synchronization in digital communication systems

A data scrambler system comprising:

• first means for receiving a serial data signal stream to be scrambled;
• and
• second means for combining the data signals of said serial data signal stream with a prescribed scrambling signal sequence in such a manner as to scramble the data signals of said serial data signal stream and to insert respective signals of said prescribed scrambling signal sequence between preselected ones of the scrambled data signals.

For use in a communication system wherein the data signals of a serial data signal stream are combined with a prescribed scrambling signal sequence in such a manner as to scramble the data signals of said serial data stream and to insert respective signals of said prescribed scrambling signal sequence between preselected ones of the scrambled data signals and thereby produced a scrambled signal stream, a descrambler for receiving said serial data signal stream comprising:

• first means, coupled to receive said scrambled signal stream, for generating a first signal sequence, corresponding to said prescribed scrambling signal sequence, in synchronism with the respective signals of the prescribed scrambling sequence inserted between preselected ones of the scrambled data signals;
• and
• second means, coupled to said first means and coupled to receive said scrambled signal stream, for generating a second signal sequence, corresponding to said prescribed scrambling sequence and combining said second signal sequence with said scrambled signal stream in such a manner as to descramble the scrambled data signals and remove the respective signals of said prescribed scrambling sequence from between said preselected ones of the data signals.

A method of scrambling data to be transmitted comprising the steps of:

• (a) inserting prescribed signals between preselected ones of the data signals of a serial data signal stream to be transmitted, thereby obtaining a modified data signal stream;
• and
• (b) combining said modified data signal stream with a prescribed scrambling signal sequence, to thereby scramble the data signals of said serial data signal stream and insert respective signals of said prescribed scrambling signal sequence in place of said prescribed signals between preselected ones of the scrambled data signals.

A method of scrambling data comprising the step of:

• combining the data signals of a serial data signal stream with a prescribed scrambling signal sequence in such a manner as to scramble the data signals of said serial data signal stream and to insert respective signals of said prescribed scrambling signal sequence between preselected ones of the scrambled data signals.

For use in a communication system wherein the data signals of a serial data signal stream are combined with a prescribed scrambling signal sequence in such a manner as to scramble the data signals of said serial data stream and to insert respective signals of said prescribed scrambling signal sequence between preselected ones of the scrambled data signals and thereby produced a scrambled signal stream, a method receiving and descrambling said scrambled signal stream to obtain said serial data stream comprising the steps of:

• (a) receiving said scrambled signal stream and generating a first signal sequence, corresponding to said prescribed scrambling signal sequence, in synchronism with the respective signals of the prescribed scrambling sequence inserted between preselected ones of the scrambled data signals;
• and
• (b) generating a second signal sequence, corresponding to said prescribed scrambling sequence and combining said second signal sequence with said scrambled signal stream in such a manner as to descramble the scrambled data signals and remove the respective signals of said prescribed scrambling sequence from between said preselected ones of the data signals to thereby obtain said serial data stream.