On the Accuracy of Wideband Localization in Quantized Uplink Massive MIMO Systems

As an essential technology for 5G and beyond, massive multiple-input multiple-output (MIMO) is well investigated in the aspect of high data-rate communication. However, its potential benefits for accurate positioning are largely undiscovered. In this letter, we derive the Cramer-Rao bound (CRB) on position estimation uncertainty in quantized uplink massive MIMO systems, where orthogonal frequency division multiplexing (OFDM) is considered and the base station (BS) uses few-bit analog-to-digital converters (ADCs) to acquire the incoming signals. With the obtained CRB, one can evaluate the dependence of localization accuracy on the system parameters, such as the number of quantization bits and different combinations of multipaths. Numerical results show that accurate localization is possible in various multipath scenarios, even with low-resolution ADCs.