Previous work on polyphase complementary codes is reviewed, and a number of new results are presented including additional kernels and lengths. Generating methods from other binary and polyphase sequences are given and negative results of other existence searches reported. Advantages of specialized forms for radar and Loran-C are discussed, including complementary Barker codes. A table of known lengths of pairs, triads and quads of sequences is given.

N-phase Codes are described which have an autocorrelation function with one main peak and very small side peaks. WithNphases anN^{2}long pulse sequence is generated. Properties have been verified forNup to8and a rule for main peak-to-side-peak ratio is conjectured for largerN. ForNgreater than5. the ratio is substantially better than the best ratios which have been shown for binary bipolar codes. Doppler shift effects appear to be similar to those of linear FM radar pulse compression.