Combining synchronization sequences of different lengths

Abstract

A system and method for generating a composite synchronization sequence in a communication system. In one embodiment, the apparatus (110, 200, 120, 300) is configured to provide a first synchronization sequence and a second synchronization sequence in a first domain, transform the first synchronization sequence and the second synchronization sequence into a second domain, and extend the first synchronization sequence and the second synchronization sequence in the second domain to a common length to produce an extended first synchronization sequence and an extended second synchronization sequence. The apparatus (110, 200, 120, 300) is also configured to transform the extended first synchronization sequence and the extended second synchronization sequence into the first domain, and multiply elementwise the extended first synchronization sequence by the extended second synchronization sequence in the first domain to obtain a composite synchronization sequence. The extension proposed is an interpolation in time domain through zero padding in frequency domain. Typically a Zadoff-Chu sequence with different cyclic shifts is combined with a m-sequence. Such a combination increases the number of available sequences for PRACH with good auto- and cross-correlation properties.

Dependencies are inferred from the claim text.