A digital (de)modulation system uses a larger code set of M codes for N length codes, where M>N, to provide an increased data rate while maintaining the coding gain. For example, the system can use 16 different codes each having a length of 11 chips in a code set while the conventional M-ary keying systems...http://www.google.de/patents/US7079567?utm_source=gb-gplus-sharePatent US7079567 - Digital modulation system using extended code set
