Influence of Roll-off Pulse Shaping on a Parallel Sequence Spread Spectrum Signal

Parallel sequence spread spectrum (PSSS) is a novel physical layer (PHY) broadband technique, that offers a flexible resource allocation and benefits against fading on wireless channels at a relatively low complexity. This spread spectrum method may especially be used in industrial radio and for high data rates in the THz range. In this paper, we first present the characteristics of the root-raised cosine (RRC) pulse shaped PSSS signal. We examine the amplitude distribution and the peak-to-average power ratio (PAPR) for different roll-off factors. Surprisingly, for large roll-off values high amplitudes become more likely. We then analyze the performance of PSSS under the influence of a memoryless nonlinearity introduced by a solid-state power amplifier (SSPA) using baseband simulation. This power amplifier (PA) is modeled using the well-established Rapp model. We compare the system to a basic orthogonal frequency-division multiplexing (OFDM) implementation.