  Traditional communications focus on regular and orthogonal signal waveforms
for simplified signal processing and improved spectral efficiency. In contrast,
the next-generation communications would aim for irregular and non-orthogonal
signal waveforms to introduce new capabilities. This work proposes a spectrally
efficient irregular Sinc (irSinc) shaping technique, revisiting the traditional
Sinc back to 1924, with the aim of enhancing performance in industrial Internet
of things (IIoT). In time-critical IIoT applications, low-latency and
time-jitter tolerance are two critical factors that significantly impact the
performance and reliability. Recognizing the inevitability of latency and
jitter in practice, this work aims to propose a waveform technique to mitigate
these effects via reducing latency and enhancing the system robustness under
time jitter effects. The utilization of irSinc yields a signal with increased
spectral efficiency without sacrificing error performance. Integrating the
irSinc in a two-stage framework, a single-carrier non-orthogonal frequency
shaping (SC-NOFS) waveform is developed, showcasing perfect compatibility with
5G standards, enabling the direct integration of irSinc in existing industrial
IoT setups. Through 5G standard signal configuration, our signal achieves
faster data transmission within the same spectral bandwidth. Hardware
experiments validate an 18% saving in timing resources, leading to either
reduced latency or enhanced jitter tolerance.
