Chip dithering using permuted randomized selection sets to enhance the LPI/LPD characteristics of a waveform

A communications system comprising:

• a mapper that converts a series of information bits to a series of bit symbols;
• a spread spectrum processor that multiplies the series of bit symbols by a sequence of chips, where a width of a chip determines the number of samples in the chip depending on where the samples occur within the chip;
• a random sequence generator generating a select random number and being responsive to commands, said random sequence generator changing the random number each time it receives the command;
• a chip width processor responsive to the random numbers from the random sequence generator, said chip width processor generating a plurality of new chips each having a certain width as a set of chips in response to receiving each random number depending on the value of the random number, where the set of chips is provided to the spread spectrum processor to be multiplied by the series of bit symbols;
• and
• a permute processor responsive to the set of chips from the chip width processor and changing the order of the chips in the set of chips.

A method for providing spread spectrum transmission in a communications system, said method comprising:

• converting a series of information bits to a series of bit symbols;
• multiplying, by a spread spectrum processor, the series of bit symbols by a sequence of chips, where a width of a chip determines the number of samples in the chip depending on where the samples occur within the chip;
• generating a first sequence of decision random numbers at a sample rate;
• generating a separate command at the sample rate each time one of the decision random numbers exceeds a predetermined threshold;
• generating a select random number and changing the select random number each time one of the commands is generated;
• and
• selecting at least one new chip having a width depending on the value of the select random number, where the new chip is provided to the spread spectrum processor to be multiplied by the series of bit symbols.