Slepian Waveform Precoding for Spectrally Efficient Wireless Transmission

The patent segments the 100 MHz contiguous band into multiple narrower sub-bands, each processed by separate filtering operations. This segmentation allows the receiver to handle each sub-band independently with simpler filters, avoiding the need for a single complex filter that would be required for the entire 100 MHz band, thus reducing receiver complexity while maintaining overall capacity and coverage.

The patent applies preliminary time-domain windowing functions to the OFDM symbols before transformation. This preliminary action in the time domain pre-localizes the signal energy, which when combined with frequency-domain filtering, achieves superior joint time-frequency localization. This preliminary preparation enables more efficient spectral utilization by reducing out-of-band emissions and improving signal confinement, thereby increasing spectral efficiency.

The patent transitions from relying solely on frequency-domain filtering to incorporating time-domain windowing operations. By adding this temporal dimension to the localization approach, the system achieves effective frequency localization without requiring excessively long filters or extended cyclic prefixes. The time-domain windowing compresses the signal energy in time, which translates to better frequency confinement without the time penalty of longer filters.

The patent develops a universal waveform structure with standardized time-domain windowing and frequency-domain filtering that can be applied across multiple carrier frequencies and bandwidth configurations. This universal approach allows the same signal processing framework to handle various carrier aggregation scenarios (different numbers of component carriers, different bandwidths) without requiring fundamentally different processing architectures, thereby reducing the complexity increment when implementing carrier aggregation for high data rates and capacity.