Linear complexity of generalised cyclotomic quaternary sequences of length 2 p m +1 q n +1

Sequences with high linear complexity play a fundamental part in cryptography. In this study, the authors construct general forms of Whiteman's generalised cyclotomic quaternary sequences with period 2p m+1 q n+1 of order two over ?4 and give the linear complexity of the proposed sequences. The conclusions reveal that such sequences have good balance property and high linear complexity.