A Study on Aperiodic Auto-Correlation Properties of Concatenated Codes by Barker Sequences and NFSR Sequences

摘要

In positioning systems, it is important to capture the signal transmitted from a beacon for getting the exact arrival time. As in the GPS systems, several beacons transmit different spreading codes, and a receiver can get the arrival time by receiving the signal in the principle of CDMA (code division multiple access) communications. In this paper, we investigate aperiodic auto-correlation properties, which are important in the CDMA-based positioning systems, of the concatenated codes obtained by a Barker sequence and an NFSR (nonlinear feedback shift register) sequence.