Method for radio bearer optimization through an adaptive access probability factor
View Patent ↗A communication system determines whether to establish a point-to-point or point-to-multipoint communication for conveyance of Multimedia Broadcast Multicast Services (MBMS) data based on a number of user equipments being serviced by the communication system for MBMS service. The system broadcasts an access probability factor in a control message to the user equipments. For a large number of MBMS users being counted, the method will select a point-to-multipoint broadcast. If the number of user equipments being counted is relatively small, the access probability factor is modified by a ratio of the number of point-to-point connections over the point-to-multipoint connections over the number of users being counted. The UE may need to join multiple base stations' in the counting procedure to obtain the system diversity gain.
1. A method for adapting an access probability for a Multimedia Broadcast Multicast Service (MBMS) service for a communication system comprising:
determining a quantity of mobile stations subscribed to the MEMS service;
setting an initial access probability factor;
broadcasting a control message comprising the initial access probability factor;
receiving from one or more mobile stations, a response to the control message;
determining whether a number of received responses from the mobile stations is zero; and
if the number of received responses is not zero, adapting a new access probability factor equal to the initial access probability factor multiplied by a ratio of a number of point-to-point connections divided by a number of point-to-multipoint connections to the number of received responses.
2. The method as claimed in claim 1 , wherein there is further included a step of if the number of received responses is zero, setting the new access probability factor equal to 1.
3. The method as claimed in claim 2 , wherein if the number of received responses is not equal to zero, there is further included a step of determining whether the new access probability factor is greater than a threshold value.
4. The method as claimed in claim 3 , wherein if the new access probability factor is greater than the threshold value, there is further included a step of setting the new access probability factor equal to 1.
5. The method as claimed in claim 4 , wherein there is further included a step of determining whether the new access probability factor is greater than 1.
6. The method as claimed in claim 5 wherein if the new access probability factor is greater than 1, there is further included a step of selecting a point-to-point broadcast communication for access to the MBMS service.
7. The method as claimed in claim 6 , wherein if the new access probability factor is greater than 1 there is further included a step of adjusting the initial access probability factor to be equal to the new access probability factor.
8. The method as claimed in claim 1 , wherein after the step of receiving from one or more mobile stations, there is further included a step of determining whether the number of received responses is greater than a ratio of point-to-point connections to a number of point-to-multipoint connections.
9. The method as claimed in claim 8 , wherein if the ratio of the number of received responses is greater than the ratio of the number of point-to-point connections to the number of point-to-multipoint connections, there is further included a step of selecting a point-to-multipoint broadcast for MBMS service.
10. The method as claimed in claim 9 , wherein there is further included a step of adjusting the initial access probability factor to be equal to the new access probability factor multiplied by a ratio of the number of point-to-point connections divided by the number of point-to-multipoint connections to the number of received responses.
11. The method as claimed in claim 1 , wherein the communication system includes a Code Division Multiple Access (CDMA) communication system.
12. The method as claimed in claim 1 , wherein the communication system includes a General Packet Radio Service (GPRS) communication system.
13. The method as claimed in claim 1 , wherein the communication system includes an Orthogonal Frequency Division Multiple Access (OFDM) communication system.
14. A method for adapting an access probability for a Multimedia Broadcast Multicast Service (MBMS) service for a communication system comprising:
determining a quantity of mobile stations subscribed to the MBMS service;
setting an initial access probability factor;
broadcasting a control message comprising the initial access probability factor;
receiving from one or more mobile stations, a response to the control message;
determining whether a number of received responses from the mobile stations is zero;
if the number of received responses is not zero, adapting a new access probability factor equal to the initial access probability factor multiplied by a ratio of the number of point-to-point connections divided by the number of point-to-multipoint connections to the number of received responses; and
determining by a mobile station whether a control connection between the mobile station and the communication system exists.
15. The method as claimed in claim 14 , wherein if the control connection does not exist, there is further included a step of selecting a random number between zero and one.
16. The method as claimed in claim 15 , wherein there is further included a step of determining whether the selected random number is less than the new access probability factor.
17. The method as claimed in claim 16 , wherein if the selected random number is less than the new access probability factor, there is further included a step of establishing by the mobile station a connection with the communication system.
18. The method as claimed in claim 14 , wherein there is further included a step of if the number of received responses is zero, setting the new access probability factor equal to 1.
19. The method as claimed in claim 18 , wherein if the number of received responses is not equal to zero, there is further included a step of determining whether the new access probability factor is greater than a threshold value.
20. The method as claimed in claim 19 , wherein if the new access probability factor is greater than the threshold value, there is further included a step of setting the new access probability factor equal to 1.
21. The method as claimed in claim 20 , wherein there is further included a step of determining whether the new access probability factor is greater than 1.
22. The method as claimed in claim 21 , wherein if the new access probability factor is greater than 1, there is further included a step of selecting a point-to-point broadcast communication for access to the MBMS service.
23. The method as claimed in claim 22 , wherein if the new access probability factor is greater than 1 there is further included a step of adjusting the initial access probability factor to be equal to the new access probability factor.
24. The method as claimed in claim 14 , wherein after the step of receiving from one or more mobile stations, there is further included a step of determining whether the number of received responses is greater than a ratio of a number of point-to-point connections to a number of point-to-multipoint connections.
25. The method as claimed in claim 24 , wherein if the ratio of the number of received responses is greater than the ratio of the number of point-to-point connections to the number of point-to-multipoint connections, there is further included a step of selecting a point-to-multipoint broadcast for MBMS service.
26. The method as claimed in claim 25 , wherein there is further included a step of adjusting the initial access probability factor to be equal to the new access probability factor multiplied by a ratio of the number of point-to-point connections divided by the number of point-to-multipoint connections to the number of received responses.
27. The method as claimed in claim 14 , wherein the step of determining whether a control connection exists includes a step of counting by a base station of the communication system the mobile station as an MBMS service user.
28. The method as claimed in claim 27 , wherein the step of counting includes a step of counting the mobile station as an MBMS service user by each of a plurality of base stations of the communication system having a control connection with the mobile station.