CP- DSSS: A Novel Waveform for Multiple Access in IoT

Abstract

Cyclic prefix direct sequence spread spectrum (CP-DSSS) is a novel waveform that positions itself well as a secondary network to relieve the congested wireless spectrum. The underlying structure of CP-DSSS allows for efficient and effective multiaccess capabilities through frequency and time division schemes. The sum-rate capacity of the system is maximized when the spectrum is divided and allocated to users with the best signal-to-noise (SNR) ratio for the given channel slice. We propose an algorithm for dividing and allocating portions of the spectrum to multiple users with the final goal of maximizing the sum-rate capacity of the network. We also propose and develop a precoding/equalization technique that reduces the length of the channel impulse response. This, when used along with a matched filter detector, leads to a noticeable improvement in the sum-rate capacity of the network.