Abstract: With its excellent anti-interference capability, low probability of interception, and code-division multiple access capability, direct sequence spread spectrum plays a crucial role in unmanned aerial vehicle swarm communications, high-precision ranging, and massive connectivity in beyond fifth-generation and sixth-generation networks. However, low spectral efficiency and poor energy concentration of conventional rectangular chip waveforms used in spread spectrum modulation make it difficult to meet the high-rate and high-sensitivity reception requirements of future systems. To address this issue, this study proposes a spread spectrum chip waveform design method based on prolate spheroidal wave functions (PSWFs). By constructing a set of four orthogonal PSWF-based chip waveforms, the proposed method enhances signal dimensionality and spectral efficiency under finite time–bandwidth product constraints. Furthermore, an equivalent low-pass filter structure is integrated to reduce implementation complexity. Theoretical analysis and simulation results demonstrate that the proposed waveform achieves approximately double the spectral efficiency of conventional waveforms while maintaining comparable error performance. It also exhibits superior anti-interference and anti-interception capabilities, providing a viable waveform design approach for next-generation spread spectrum communication systems.

基于椭圆球面波函数的新型四维直接序列扩频波形设计

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