  Orthogonal Frequency Division Multiple Access (OFDMA) with Dynamic spectrum
allocation (DSA) is able to provide a wide range of data rate requirements.
This paper is focused on the design of preamble sequences in OFDMA systems with
low peak-to-mean envelope power ratio (PMEPR) property in the context of DSA.
We propose a systematic preamble sequence design which gives rise to low PMEPR
for possibly non-contiguous spectrum allocations. With the aid of
Golay-Davis-Jedwab (GDJ) sequences, two classes of preamble sequences are
presented. We prove that their PMEPRs are upper bounded by 4 for any DSA over a
chunk of four contiguous resource blocks.
