The well known family of binary twin-prime sequences is generalised to the
multiple-valued case by employing a polyphase representation of the sequenc
e elements. These polyphase versions exhibit similar periodic and aperiodic
auto-correlation properties to their binary counterparts, and are referred
to as q-phase related-prime (RP) sequences. These sequences have length L
= r.s, for r and s both prime, and with s = r + k. They are constructed by
combining two polyphase Legendre sequences of lengths r and s, and modifyin
g the resulting composite sequence at certain points. A two-dimensional arr
ay structure is employed in the construction and analysis of these sequence
s. The original q-phase Legendre sequences are derived by converting the in
dex sequences of lengths r and s to modulo-q form. When q is even, two clas
ses of RP sequence arise, depending on whether L = q + 1 mod 2q or L = 1 mo
d 2q. For odd q, only a single class is available, and here L = 1 mod 2q. T
he out-of-phase periodic correlation values of these RP sequences are indep
endent of the sequence length, and depend only on the number of phases q an
d the difference k between the two related primes. The maximum out-of-phase
correlation values is given by 1 - k. Tables of available sequences are pr
esented.