  Radio stripes (RSs) is an emerging technology in beyond 5G and 6G wireless
networks to support the deployment of cell-free architectures. In this paper,
we investigate the potential use of RSs to enable joint positioning and
synchronization in the uplink channel at sub-6 GHz bands. The considered
scenario consists of a single-antenna user equipment (UE) that communicates
with a network of multiple-antenna RSs distributed over a wide area. The UE is
assumed to be unsynchronized to the RSs network, while individual RSs are time-
and phase-synchronized. We formulate the problem of joint estimation of
position, clock offset, and phase offset of the UE and derive the corresponding
maximum-likelihood (ML) estimator, both with and without exploiting carrier
phase information. To gain fundamental insights into the achievable
performance, we also conduct a Fisher information analysis and inspect the
theoretical lower bounds numerically. Simulation results demonstrate that
promising positioning and synchronization performance can be obtained in
cell-free architectures supported by RSs, revealing at the same time the
benefits of carrier phase exploitation through phase-synchronized RSs.
