IP Library Granted Patent US 12,550,003
Granted Patent B2
US 12,550,003 · App. 17/841,325 · Granted Feb 10, 2026

Repurposing mobility management with virtual radio in software radio access networks

Inventors: Manikanta Kotaru (Kenmore, WA); Paramvir Bahl (Bellevue, WA); Daehyeok Kim (Redmond, WA); Xenofon Foukas (Cambridge, GB)
Assignee: Microsoft Technology Licensing, LLC
H04W28/0831H04W28/0858H04W28/086H04W36/08
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Quick Facts
Patent No.
US 12,550,003
App. No.
17/841,325
Granted
Feb 10, 2026
Kind
B2
Abstract

Described are examples for repurposing mobility management with virtual radio in software radio access networks. A virtual mobile network includes a first server configured to host a first mobile network distributed unit (DU) for providing a first virtual cell to a plurality of user devices via a radio unit. The virtual mobile network also includes a second server configured to host a second mobile network distributed unit providing a second virtual cell via the same radio unit. A radio access network (RAN) intelligent controller (RIC) is configured to control the first DU and the second DU to hand over the plurality of user devices from the first virtual cell to the second virtual cell. The first server may then be shut down for maintenance or updates without dropping service to the user devices.

Claims (28)

1 . A virtual mobile network comprising:

a radio unit;

a first server configured to host a first mobile network distributed unit (DU) for providing a first virtual cell to a plurality of user devices via the radio unit;

a second server configured to host a second mobile network distributed unit providing a second virtual cell via the radio unit; and

a radio access network (RAN) intelligent controller (RIC) configured to control the first DU and the second DU to hand over the plurality of user devices from the first virtual cell to the second virtual cell, wherein the first virtual cell and the second virtual cell have a same center frequency and are assigned different frequency domain resources.

2 . The virtual mobile network of claim 1 , wherein the RIC is configured to control the first DU and the second DU to perform an inter-gNB-DU handover for each of the plurality of user devices when the first mobile network DU is not co-located with a mobile network central unit.

3 . The virtual mobile network of claim 1 , wherein the RIC is configured to control the first DU and the second DU to perform a handover via an Access and Mobility Management Function (AMF) for each of the plurality of user devices when the first mobile network DU is co-located with a mobile network central unit (CU).

4 . The virtual mobile network of claim 1 , further comprising a hypervisor configured to combine in-phase and quadrature (IQ) samples from the first mobile network DU and the second mobile network DU for the radio unit.

5 . The virtual mobile network of claim 1 , wherein the RIC is configured to shut down the first server when no user devices are connected to the first virtual cell.

6 . The virtual mobile network of claim 1 , wherein the RIC is configured to initialize the second virtual cell on the second server prior to controlling the first DU and the second DU to hand over the plurality of user devices.

7 . The virtual mobile network of claim 1 , wherein the first virtual cell and the second virtual cell are configured with a same transmission power.

8 . The virtual mobile network of claim 1 , wherein the RIC is configured to control the first DU and the second DU to hand over the plurality of user devices based on load balancing between the first server and the second server.

9 . The virtual mobile network of claim 1 , wherein the first server is configured to host a first central unit, wherein the RIC is configured to control the first DU to hand over one or more of the user devices to a third virtual cell provided by a third DU on the first server and supported by a second central unit on the second server.

10 . A method, comprising:

determining to reduce a load on a first server hosting a first mobile network distributed unit (DU) for providing a first virtual cell to a plurality of user devices via a radio unit;

identifying a second server hosting a second mobile network DU providing a second virtual cell via the radio unit; and

handing over the plurality of user devices from the first virtual cell to the second virtual cell, wherein the first virtual cell and the second virtual cell have a same center frequency and are assigned different frequency domain resources.

11 . The method of claim 10 , wherein handing over the plurality of user devices comprises performing an inter-gNB-DU handover for each of the plurality of user devices when the first mobile network DU is not co-located with a mobile network central unit.

12 . The method of claim 10 , wherein handing over the plurality of user devices comprises performing a handover via an Access and Mobility Management Function (AMF) for each of the plurality of user devices when the first mobile network distributed unit is co-located with a mobile network central unit.

13 . The method of claim 10 , further comprising combining in-phase and quadrature (IQ) samples from the first mobile network DU and the second mobile network DU for the radio unit.

14 . The method of claim 10 , further comprising shutting down the first server when no user devices are connected to the first virtual cell.

15 . The method of claim 10 , further comprising initializing the second virtual cell via the radio unit on the second server in response to determining to reduce the load on the first server.

16 . The method of claim 10 , wherein the first virtual cell and the second virtual cell are configured with a same transmission power.

17 . The method of claim 10 , wherein the first server is configured to host a first central unit, further comprising handing over one or more user devices to a third virtual cell provided by a third DU on the first server and supported by a second central unit on the second server.

18 . A non-transitory computer-readable medium storing computer-executable instructions that when executed by a processor cause the processor to:

determine to reduce a load on a first server hosting a first mobile network distributed unit (DU) for providing a first virtual cell to a plurality of user devices via a radio unit;

identify a second server hosting a second mobile network DU providing a second virtual cell via the radio unit; and

hand over the plurality of user devices from the first virtual cell to the second virtual cell, wherein the first virtual cell and the second virtual cell have a same center frequency and are assigned different frequency domain resources.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 26, 2023
From: KOTARU, MANIKANTA; BAHL, PARAMVIR; KIM, DAEHYEOK; FOUKAS, XENOFON
To: MICROSOFT TECHNOLOGY LICENSING, LLC
Reel/Frame 063443/0987 →
Continuity (1)
Related Publication 20230413111A1 · Dec 21, 2023
References Cited (11)
US 20160029205A1 · Sirotkin · 2016 [cited by applicant]
US 20170318516A1 · Huang · 2017 [cited by examiner]
US 20170353903A1 · Rost · 2017 [cited by examiner]
US 20180139655A1 · Hsu et al. · 2018 [cited by applicant]
US 20180376380A1 · Leroux · 2018 [cited by examiner]
US 20230300701A1 · Wang · 2023 [cited by examiner]
US 20240305533A1 · Bai · 2024 [cited by examiner]
US 20240334200A1 · Jamadagni · 2024 [cited by examiner]
WO 2021242153A1 · 2021 [cited by applicant]
“Network Functions Virtualisation (NFV) Release 5; Architectural Framework; Report on NFV support for virtualization of RAN”, In ETSI Draft Specification, ETSI GR NFV-IFA 046, Jun. 13, 2022, 58 Pages. [cited by applicant]
“International Search Report and Written Opinion Issued in PCT Application No. PCT/US2023/021789”, Mailed Date: Aug. 24, 2023, 13 Pages. [cited by applicant]