A study on 5G performance and fast conditional handover for public transit systems

Fifth-generation (5G) networks are now in a stable phase in terms of commercial release. 5G design is flexible to support a diverse range of radio bands (i.e., low-, mid-, and high-band) and application requirements. Since its initial roll-out in 2019, extensive measurements studies have revealed key aspects of commercial 5G deployments (e.g., coverage, signal strength, throughput, latency, handover, and power consumption among others) for several scenarios (e.g., pedestrian and car mobility, mid-, and high-bands, etc.). In this paper, we make a twofold contribution. First, we carry out an in-depth measurement study of 5G in a large public bus transit system in a major European city. Second, based on the insights observed with the measurement study, we propose a new target cell selection criteria applicable to Fast Conditional Handover (FCHO), a 3GPP-specific 5G technique to foster reliable mobility. Our results are based on an extensive measurement campaign performed with several mobile phones connected to several mobile network operators totaling more than 1500 km over three months. The measurements reveal how flexible the network deployment is by analyzing Radio Resource Control (RRC) messages, mobility management and the suitability of our FCHO solution, and application performance.