Doubly Spread SS/CDMA Signals for GNSS

Kurzfassung

In this paper we propose a new way of designing a GNSS signal using a Spread-Spectrum-Code-Division- Multiple-Access (SS/CDMA) in which the spreading operation is performed by means of frequency-domain and time-domain signature sequences. Each user is allocated a spreading matrix, which is a key parameter design, as it affects several aspects of the signal performance. In this work we propose a simple optimization strategy for the spreading matrix for either a GNSS pilot signal or a GNSS data channel signal, with the aim of minimising the Multiple-Access-Interference (MAI) and the Peakto- Average-Power-Ratio (PAPR), while at the same time preserving a certain freedom for the spectral shaping of the signal.