Low Cubic Metric Reed-Muller Sequence Design for Pilot-Less Transmission

A versatile sequence set design with both low cubic metric (CM) and low maximum-absolute-crosscorrelation is proposed for pilot-less sequence-based transmission as a solution to current pilot/symbol-based 5G design in coverage-limited scenarios. Based on generalized second-order Reed-Muller sequences that provide already sequence length flexibility and good correlation properties, a modified construction is introduced to achieve a very low CM for any resource allocation. New sequences inherently incorporate a symbol spreading pattern matching the signal bandwidth, leading to a windowing effect that limits the time-domain signal variations. Simulation results show that the proposed design effectively improves CMs and outperforms error rates of current 5G NR uplink control signals.