Orthogonal polyphase code sets with master codes

The derivation of orthogonal code sets to improve radar spectrum efficiency is examined. Properties of orthogonal codes and metrics are chosen for optimising code sets. A search technique is then described using an evolutionary algorithm to find suitable polyphase codes. An interference rejection technique is also described to improve isolation from interference sources and to show the need for code sets with a master code. Orthogonal polyphase code sets with master codes are then found using the evolutionary algorithm. Code set properties such as the sidelobe, cross correlation and master code performances are examined for various code lengths and set sizes.