z on the unit circle, that is, |z| = 1. If so, A and B form a Golay pair of polynomials. Examples include the Shapiro polynomials, which give rise to complementary sequences of length a power of two. Applications of complementary sequences Multislit spectrometry Ultrasound measurements Acoustic measurements radar pulse compression Wi-Fi networks, 3G CDMA wireless networks OFDM communication systems Train wheel detection systems Non-destructive tests (NDT) Communications coded aperture masks are designed using a 2-dimensional generalization of complementary sequences. See also Binary Golay code (Error-correcting code) Gold sequences Kasami sequences Polyphase sequence Pseudorandom binary sequences (also called maximum length sequences or M-sequences) Ternary Golay code (Error-correcting code) Walsh-Hadamard sequences Zadoff–Chu sequence References Sequences and series Signal processing Pseudorandom number generators