RFID Localization via Wideband Backscatter

A wideband, radio-frequency localization system may estimate the one-dimensional, two-dimensional or three-dimensional position and trajectory of a static or moving object. These estimates may have a high spatial accuracy and low latency. The localization may be determined based on phase or amplitude of a wideband signal in each frequency band in a set of multiple frequency bands. The localization may be based on a single shot of measurements across a wide band of radio frequencies, without frequency hopping. The measurements of the wideband signal may be taken over time and over space at multiple receivers. The localization may be based on measurements taken while a backscatter node remains in a first reflective state or in a second reflective state, rather than when the backscatter node is transitioning between reflective states. In some cases, the localization achieves sub-centimeter spatial resolution in each of three spatial dimensions.