Two-Step FMCW Channel Estimation Across Ultra-Wide Bandwidths

The patent divides the channel estimation process into two sequential steps: first transmitting a wideband FMCW reference signal to cover the entire frequency range, then transmitting a narrowband FMCW reference signal at specific frequency locations to obtain high-resolution channel estimates. This segmentation allows the system to achieve both wide frequency coverage and high measurement precision without requiring a single overly complex wideband measurement.

The patent dynamically adjusts the FMCW bandwidth parameter based on the specific measurement task. Instead of using a fixed high-bandwidth configuration that requires high ADC rates continuously, the system selects an appropriate bandwidth for each reference signal transmission. The wideband signal provides overview coverage while the narrowband signal provides detailed estimation, allowing the ADC to operate at lower rates for the majority of the measurement process, thus reducing overall energy consumption while maintaining precision where needed.

The patent changes the FMCW bandwidth parameter adaptively based on channel conditions and measurement requirements. The system transmits a wideband FMCW reference signal when broad frequency coverage is needed, and switches to a narrowband FMCW reference signal when high frequency resolution is required at specific locations. This parameter change approach allows the system to adapt to different channel conditions without requiring a completely complex fixed configuration, maintaining flexibility while managing device complexity through software-controlled parameter selection.