Parallel sequence spread spectrum (PSSS) is a novel physical layer (PHY) technique allowing a flexible resource allocation through code multiplexing. This broadband technique is designed for high data rates in industrial applications, as it offers benefits in fading environments at a relatively low hardware complexity. In this paper we compare different approaches for the equalization of wireless channels in a PSSS communication system. For this purpose we employ multiple baseband impulse responses representing diverse transmission conditions. We analyze the performance of the cyclic prefix based PSSS design from previous work and compare it with our more efficient equalization approaches.

We propose a closed-loop industrial radio system with a star topology for factory automation using Parallel Sequence Spread Spectrum (PSSS) technology. This system implements all significant concepts for synchronization, duplex-communication, channel estimation/equalization based on an innovative transceiver concept. The industrial environment tends to have non-line of sight channels that lead to RMS delay spreads of less than 100 ns. Here, we propose a channel equalization scheme to compensate for these delay spreads. Another challenging aspect is the implementation of a code division duplexing (CDD) scheme. We propose a closed-loop system architecture that can achieve the targets set by Industry 4.0 bodies such as IWSAN. This paper gives an overview of the closed-loop systems concept.

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.

Parallel Sequence Spread Spectrum (PSSS) is a spread spectrum physical layer (PHY) offering beneficial properties against the effects of fading as well as the possibility of a flexible resource allocation, while maintaining a low complexity. Additionally it is being investigated for high data rates in the THz range. In this paper, we give an overview on the current state of research on PSSS, its advantages, but also its challenges. We present simulations and measurements comparing the performance of PSSS with OFDM, showing its potential for future wireless communications.