Method for improved roaming of a limited-bandwidth user equipment
Provided is a method to operate a user equipment operating in a cellular network different from the user equipment's home cellular network, the user equipment being configured to carry out, following a periodic home network scan cycle, a measurement attempt to the home cellular network, the user equipment operating in a reduced activity mode, comprising reduced measurement activity time periods, comprising the step of comparing the periodic home network scan cycle with the reduced activity mode's reduced measurement activity time period, in case the periodic home network scan cycle is shorter than the reduced measurement activity time period, amending the periodic home network scan cycle.
1. A method of operating a user equipment operating in a cellular network different from the user equipment's home cellular network, the user equipment being configured to carry out, following a periodic home network scan cycle, a measurement attempt to the home cellular network, the user equipment operating in a reduced activity mode, comprising reduced measurement activity time periods,
the method comprising the steps of comparing the periodic home network scan cycle with the reduced activity mode's reduced measurement activity time period, and,
in case the periodic home network scan cycle is shorter than the reduced measurement activity time period, amending the periodic home network scan cycle.
2. The method according to claim 1 , wherein the reduced activity mode comprises an increased enhanced discontinuous reception mode, and the step of amending the periodic home network scan cycle considers the reduced measurement activity time period, wherein the reduced measurement activity time period complements to the increased discontinuous reception cycle.
3. The method according to claim 1 , wherein the reduced activity mode comprises a relaxed monitoring mode, and the step of amending the periodic home network scan cycle considers the reduced measurement activity time period wherein the reduced measurement activity time period complements to neighbor cell measurement cycle.
4. The method according to claim 1 , wherein the user equipment is at least one of:
operated stationary,
operated in a limited-bandwidth mode.
5. The method according to claim 1 , wherein the user equipment is camping on a base station of said cellular network,
further comprising the step of receiving signals from said base station comprising an indication of an amended periodic home network scan cycle,
wherein the step of amending the periodic home network scan cycle considers said received indication.
6. The method according to claim 5 , wherein the signal received from the base station is received in response to amending the periodic home network scan cycle considering the reduced measurement activity time period.
7. The method according to claim 6 ,
the user equipment further comprising a subscriber identity card, the method comprising at least one memory field for storing at least two values for the periodic home network scan cycle, wherein the method comprises the step of ascertaining the value of said at least two values for the periodic home network scan cycle that is designated for a user equipment ( 1 ) operating in reduced activity mode.
8. The method according to claim 4 ,
further comprising the step of evaluating if the user equipment ( 1 ) is operating stationary,
where the step of amending periodic home network scan cycle is carried out only in case the evaluation results indicates a stationary operation.
9. A user equipment configured to operate in a cellular network different from the user equipment's home cellular network, the user equipment being further configured to carry out, following a periodic home network scan cycle, a measurement attempt to the home cellular network, and to operate in a reduced activity mode, comprising reduced measurement activity time periods,
wherein the user equipment is further configured to compare the periodic home network scan cycle with the reduced activity mode's reduced measurement activity time period, and
in case the periodic home network scan cycle is shorter than the reduced measurement activity time period, amend the periodic home network scan cycle.
10. The user equipment according to claim 9 , wherein for amending the periodic home network scan cycle the user equipment is configured to consider the reduced measurement activity time period, wherein the reduced activity mode comprises at least one of:
an increased enhanced discontinuous reception mode, wherein the reduced measurement activity time period complements to the increased discontinuous reception cycle, and
a relaxed monitoring mode, wherein the reduced measurement activity time period complements to neighbor cell measurement cycle.
11. The user equipment according to claim 10 , the user equipment camping on a base station of said cellular network, and further being configured to receive signals from said base station comprising an indication of an amended periodic home network scan cycle, wherein for amending the periodic home network scan cycle the user equipment is configured to consider said received indication.
12. The user equipment according to claim 11 , wherein the user equipment is configured to evaluate if the user equipment is operating stationary, and to amend the periodic home network scan cycle the user equipment only in case the evaluation results indicates a stationary operation.
13. The user equipment according to claim 12 , wherein the user equipment further comprising a subscriber identity card, comprising at least one memory field for storing at least two values for the periodic home network scan cycle, wherein the user equipment is further configured to ascertaining from the subscriber identity card the value of said at least two values for the periodic home network scan cycle that is designated for a user equipment operating in reduced activity mode.
14. A system comprising the user equipment according to claim 11 and further comprising a base station, wherein the base station is configured to transmit an indication to the user equipment indicating the amended periodic home network scan cycle.
15. The system according to claim 14 , wherein said indication is transmitted in a broadcast of system information dedicated for limited-bandwidth user equipments.
16. The system according to claim 15 , wherein the base station is further configured to determine that a user equipment camping on the base station amended the periodic home network scan cycle, and in response to transmit said indication to said user equipment.
17. The user equipment of claim 12 , further comprising a Subscriber identity module configured to be communicatively coupled to the user equipment, and comprising a memory unit, configured to store at least two values for the periodic home network scan cycle, wherein one of said values for the periodic home network scan cycle is designated for a user equipment operating in reduced activity mode.