Orthogonal CDMA system utilizing direct sequence pseudo noise codes

An orthogonal code division multiple access communication system comprising:

• a plurality of user communications apparatus, each having transmitter and receiver means;
• each said transmitter means including:
• a code generator means for generating a different time permutation of the same n-bit, direct-sequence, noise coded signal and wherein each said bit assumes either one of two possible digital values
• a bit stuffer means for adding, at the same location in each of said coded signals, a common bit to balance the values of said bits in said signal and thereby form an (n+1)-bit noise coded signal and wherein the number of bits of one of said digital values equals the number of bits of the other of said digital values;
• each of said (n+1)-bit signals having a crosscorrelation value of zero with a linear composite of the other of said (n+1)-bit signals when mutually synchronous with each other;
• each said receiver means including a coherent detection means for autocorrelation detecting one of said (n+1)-bit signals and for eliminating interfernece from the other of said signals through crosscorrelation detection;
• and
• means for providing a synchronous timed reference for said plurality of user communication apparatus.