Multi-Frequency Upper Mid-Band Localization

The upper mid-band, often referred to as FR3, embodies an attractive balance of coverage and spectrum availability. As such, it is envisioned to be a pivotal band for future wireless communication, whose unique characteristics also offer enticing opportunities for RF localization. In this context, the lower FR3 band provides great range but limited resolution due to smaller bandwidth and antenna array size; conversely, higher FR3 frequencies are limited in range due to pronounced path loss attenuation, but offer wider bandwidth and larger antenna counts, which result in greater resolution. This paper explores user localization in an uplink scenario, leveraging multiple sub-bands within FR3 to reduce the localization root mean squared error (RMSE) as compared to localization performed using a single sub-band. We introduce a novel FR3 beamformer that capitalizes on the different analog front-ends and spectral behavior associated with each sub-band. The efficiency of our scheme is evaluated for localization in a challenging urban scenario depicting the heavily clustered NYC Herald Square.