NTT DOCOMO has expanded its use of D-Wave quantum technology to a second hybrid-quantum application that minimizes paging and location-registration signals at the same time. The application has been deployed and is now in operation nationwide.
The carrier serves more than 93 million subscriptions across a national network of roughly 250,000 base stations. For a segment of 333 base stations, three TA-Lists and nine TAs, the solver completed the optimization in approximately five minutes. That segment has 2 8991 possible configurations.
Across the 333 base station segment, the application reduced the daily peak volume of location-registration signals by 65.3% and paging signals by 7%. DOCOMO's previous classical methods could not solve this problem within the time required for production use.
DOCOMO has used D-Wave's constrained quadratic model (CQM) hybrid solver in production since 2024 to optimize paging-signal traffic within individual TAs. Using mobile traffic data from three regions, that application reorganized 270 base stations into 21 TA-Lists, a problem that took 27 hours with classical methods compared with 40 seconds using D-Wave's platform. Once deployed, it reduced peak-period paging signals by roughly 15%, giving an estimated 20% more capacity for connected devices.
The new application uses D-Wave's CQM hybrid solver, which combines classical computing with the Advantage2 annealing quantum computer, through the Leap quantum cloud service. DOCOMO also built a map-based visualization tool that converts the output into a base-station reassignment plan for review by regional branch offices.
Source: D-Wave news
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