# A Reliable Low-Latency Multipath Routing Algorithm for Urban Rail Transit Ad Hoc Networks
## 3 The Improved Multipath Routing Algorithm
### RLLMR Algorithm
Static route configuration solves the problem of a long multipath route discovery time, the AMS algorithm adaptively adjusts the number of parallel paths according to the latency requirements of different services to improve the transmission efficiency, and the LRM scheme reduces the maintenance cost by replacing the alternate path with maintenance nodes and shortens the repair latency by establishing temporary paths with maintenance nodes. Finally, the RLLMR algorithm is simulated and compared with the traditional AODV and AOMDV. The results show that the RLLMR algorithm for urban rail transit ad hoc networks can reduce the latency and packet loss rate, and it is suitable for the next-generation urban rail transit vehicle-ground communication system, which carries several services. Conceptualization, H.H. and F.B. ; methodology, L.S. ; software, L.S. ; validation, L.S., S.C. and Z.S. ; formal analysis, L.S. ; investigation, Z.H. ; resources, L.L. ; data curation, L.S. ; writing--original draft preparation, L.S. ; writing--review and editing, L.L. ; supervision, L.L. ; project administration, H.H. ; funding acquisition, L.L. All authors have read and agreed to the published version of the manuscript. This research was supported by the Beijing Natural Science Foundation under the grant of [L211002]. Not applicable. Due to the fact that the data in this paper will continue to be used in the future, the participants of this study did not allow data to be publicly shared. The paper was completed entirely by the listed authors and approved by all authors for publication. Anyone else who contributed to the manuscript but does not qualify for authorship has been acknowledged with their permission. The authors declare that there are no conflict of interest regarding the publication. ## References

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