UWB PPDU Synchronization Sequences for Multi-Device Interference

The patent segments the synchronization sequence design by introducing specific autocorrelation and cross-correlation properties. The first sequence is designed with periodic autocorrelation characteristics where the main lobe amplitude is non-zero and side lobe amplitude is zero, while the second sequence is designed with cross-correlation characteristics having at most three different values. This segmentation of correlation properties reduces mutual interference between concurrent transmissions.

The patent changes the correlation function parameters of the synchronization sequences. Specifically, it defines sequences with controlled periodic autocorrelation and cross-correlation functions, where the cross-correlation function has a limited number of different values (maximum three). This parameter control ensures that when multiple devices transmit simultaneously, the interference patterns are bounded and manageable, preventing transmission failures.

The patent applies local quality by differentiating the correlation properties at different locations in the correlation function domain. The first sequence maintains perfect periodic autocorrelation characteristics (main lobe non-zero, side lobes zero) for accurate timing detection, while the second sequence controls cross-correlation values to have at most three different values to minimize interference. This localized optimization of correlation properties achieves both goals simultaneously.

The patent introduces asymmetry in the correlation function design between the first and second sequences. The first sequence is optimized for autocorrelation properties to enable precise timing synchronization, while the second sequence is optimized for cross-correlation properties to reduce interference with other devices. This asymmetric design allows each sequence to excel at its specific function without compromising the other.