Systems and methods for maintaining constant closed subscriber group cell reselection radius
View Patent ↗A method for self-configuration of offset factors between two base stations in a wireless communications system is described. A first offset factor is sent to a first user equipment (UE) by a first base station. An offset factor is an indication of the reselection area around a home evolved nodeB (HeNB). A second offset factor is received from a second UE. The first offset factor is modified using the second offset factor. The modified first offset factor is sent to the first UE.
1. A method for adaptive pilot power transmission for a home evolved NodeB (HeNB) in a cell, the method comprising:
establishing, by the HeNB, a re-selection area around the HeNB in accordance with an offset factor, an HeNB pilot power level of the HeNB, and a path loss;
measuring, by the HeNB, a pilot power of a pilot signal received from a macro evolved NodeB (eNodeB);
estimating, by the HeNB, an updated path loss in accordance with the measured pilot power; and
adjusting, by the HeNB, the HeNB pilot power level in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor,
wherein adjusting the HeNB pilot power level in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor comprises adjusting the HeNB pilot power level to maintain a radius of the re-selection area above or below a threshold.
2. The method of claim 1 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the macro eNode B.
3. The method of claim 1 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the UE.
4. The method of claim 1 , wherein adjusting the HeNB pilot power level to maintain the re-selection area around the HeNB comprises:
adjusting the HeNB pilot power level to maintain a radius of the re-selection area within a range.
5. The method of claim 1 , wherein adjusting the HeNB pilot power level to maintain the re-selection area around the HeNB comprises:
adjusting the HeNB pilot power level to compensate for the updated path loss being different than the path loss.
6. The method of claim 1 , wherein adjusting the HeNB pilot power level to maintain the re-selection area around the HeNB comprises:
adjusting the HeNB pilot power level in accordance with the following equation:
Pr ,UE= Pcsg ,pilot− Pcsg ,losses( r )−Pen B ,interference( d ),
where Pr,UE is a receive power of the UE, Pcsg,pilot is a pilot transmit power of an HeNB, Pcsg,losses(r) is a path loss from the HeNB to the UE at a distance r, and PenB,interference(d) is an interference caused by the eNodeB at a distance d from the HeNB.
7. A method for adaptive pilot power transmission for a home evolved NodeB (HeNB) in a cell, the method comprising:
establishing, by the HeNB, a re-selection area around the HeNB in accordance with an offset factor, an HeNB pilot power level, and a path loss;
receiving, by the HeNB, measurement reports from a user equipment (UE), wherein the measurement reports indicate a measured interference resulting from transmissions of a macro evolved NodeB (eNodeB);
estimating, by the HeNB, an updated path loss in accordance with the measured interference; and
adjusting, by the HeNB, a HeNB pilot power of the HeNB in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor,
wherein adjusting HeNB pilot power of the HeNB in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor comprises adjusting the HeNB pilot power level to maintain a radius of the re-selection area above or below a threshold.
8. The method of claim 7 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the macro eNode B.
9. The method of claim 7 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the UE.
10. The method of claim 7 , wherein adjusting the HeNB pilot power level to maintain the re-selection area around the HeNB comprises:
adjusting the HeNB pilot power level to maintain a radius of the re-selection area within a range.
11. The method of claim 7 , wherein adjusting the HeNB pilot power level to maintain the re-selection area around the HeNB comprises:
adjusting the HeNB pilot power level to compensate for the updated path loss being different than the path loss.
12. The method of claim 7 , wherein adjusting the HeNB pilot power level to maintain the re-selection area around the HeNB comprises:
adjusting the HeNB pilot power level in accordance with the following equation:
Pr ,UE= Pcsg ,pilot− Pcsg ,losses( r )−Pen B ,interference( d ),
where Pr,UE is a receive power of the UE, Pcsg,pilot is the pilot transmit power of an HeNB, Pcsg,losses(r) is a path loss from the HeNB to the UE at a distance r, and PenB,interference(d) is an interference caused by the eNodeB at a distance d from the HeNB.
13. A home evolved NodeB (HeNB) comprising:
a first unit configured to establish a re-selection area around the HeNB in accordance with an offset factor, an HeNB pilot power level of the HeNB, and a path loss;
a measurement unit, in the HeNB, configured to measure a pilot power of a pilot signal received from a macro evolved NodeB (eNodeB);
a second unit configured to estimate an updated path loss in accordance with the measured pilot power; and
an adjustment unit configured to adjust the HeNB pilot power level in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor,
the adjustment unit being configured to adjust the HeNB pilot power level in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor by adjusting the HeNB pilot power level to maintain a radius of the re-selection area above or below a threshold.
14. The HeNB of claim 13 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the macro eNode B.
15. The HeNB of claim 13 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the UE.
16. The HeNB of claim 13 , wherein the adjustment unit is further configured to:
adjust the HeNB pilot power level to maintain a radius of the re-selection area within a range.
17. The HeNB of claim 13 , wherein the adjustment unit is further configured to:
adjust the HeNB pilot power level to compensate for the updated path loss being different than the path loss.
18. The HeNB of claim 13 , wherein the adjustment unit is further configured to:
adjust the HeNB pilot power level in accordance with the following equation:
Pr ,UE= Pcsg ,pilot− Pcsg ,losses( r )−Pen B ,interference( d ),
where Pr,UE is a receive power of the UE, Pcsg,pilot is the pilot transmit power of an HeNB, Pcsg,losses(r) is a path loss from the HeNB to the UE at a distance r, and PenB,interference(d) is an interference caused by the eNodeB at a distance d from the HeNB.
19. A communications apparatus comprising:
a first unit configured to establish a re-selection area around a home evolved NodeB (HeNB) in accordance with an offset factor, an HeNB pilot power level of the HeNB, and a path loss;
a receiving unit configured to receive measurement reports from a user equipment (UE), wherein the measurement reports indicate a measured interference resulting from transmissions of a macro evolved NodeB (eNodeB);
a second unit configured to estimate an updated path loss in accordance with the measured interference; and
an adjustment unit configured to adjust the HeNB pilot power level in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor,
the adjustment unit being configured to adjust the HeNB pilot power level in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor by adjusting the HeNB pilot power level to maintain a radius of the re-selection area above or below a threshold.
20. The communications apparatus of claim 19 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the macro eNode B.
21. The communications apparatus of claim 19 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the UE.
22. The communications apparatus of claim 19 , wherein the adjustment unit is further configured to:
adjust the HeNB pilot power level to maintain a radius of the re-selection area within a range.
23. The communications apparatus of claim 19 , wherein the adjustment unit is further configured to:
adjust the HeNB pilot power level to compensate for the updated path loss being different than the path loss.
24. The communications apparatus of claim 19 , wherein the adjustment unit is further configured to:
adjust the HeNB pilot power level in accordance with the following equation:
Pr ,UE= Pcsg ,pilot− Pcsg ,losses( r )−Pen B ,interference( d ),
where Pr,UE is a receive power of the UE, Pcsg,pilot is the pilot transmit power of an HeNB, Pcsg,losses(r) is a path loss from the HeNB to the UE at a distance r, and PenB,interference(d) is an interference caused by the eNodeB at a distance d from the HeNB.
25. A non-transitory computer-readable medium having programming for execution by a processor for causing the processor to perform a method for adaptive pilot power transmission for a home evolved NodeB (HeNB) in a cell, the programming including instructions to:
establish a re-selection area around the HeNB in accordance with an offset factor, an HeNB pilot power level of the HeNB, and a path loss;
measure, by the HeNB, a pilot power of a pilot signal received from a macro evolved NodeB (eNodeB);
estimate an updated path loss in accordance with the measured pilot power; and
adjust the HeNB pilot power level of the HeNB in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor,
wherein the instructions to adjust the HeNB pilot power level to maintain the re-selection area around the HeNB without adjusting the offset factor include instructions to adjust the HeNB pilot power level to maintain a radius of the re-selection area above or below a threshold.
26. The non-transitory computer-readable medium of claim 25 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the macro eNode B.
27. The non-transitory computer-readable medium of claim 25 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the UE.
28. The non-transitory computer-readable medium of claim 25 , wherein the instructions to adjust the HeNB pilot power level to maintain the re-selection area around the HeNB include instructions to:
adjust the HeNB pilot power level to maintain a radius of the re-selection area within a range.
29. The non-transitory computer-readable medium of claim 25 , wherein the instructions to adjust the HeNB pilot power level to maintain the re-selection area around the HeNB include instructions to:
adjust the HeNB pilot power level to compensate for the updated path loss being different than the path loss.
30. The non-transitory computer-readable medium of claim 25 , wherein the instructions to adjust the HeNB pilot power level to maintain the re-selection area around the HeNB include instructions to:
adjust the HeNB pilot power level in accordance with the following equation:
Pr ,UE = Pcsg ,pilot− Pcsg ,losses( r )−Pen B ,interference( d ),
where Pr,UE is a receive power of the UE, Pcsg,pilot is the pilot transmit power of an HeNB, Pcsg,losses(r) is a path loss from the HeNB to the UE at a distance r, and PenB,interference(d) is an interference caused by the eNodeB at a distance d from the HeNB.
31. A non-transitory computer-readable medium having programming for execution by a processor for causing the processor to perform a method for adaptive pilot power transmission for a home evolved NodeB (HeNB) in a cell, the programming including instructions to:
establish a re-selection area around the HeNB in accordance with an offset factor, an HeNB pilot power level of the HeNB, and a path loss;
receive measurement reports from a user equipment (UE), wherein the measurement reports indicate a measured interference resulting from transmissions of a macro evolved NodeB (eNodeB);
estimate an updated path loss in accordance with the measured interference; and
adjust a HeNB pilot power level of the HeNB in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor,
wherein the instructions to adjust the HeNB pilot power level of the HeNB in accordance with the updated path loss in order to maintain the re-selection area around the HeNB without adjusting the offset factor include instructions to adjust the HeNB pilot power level to maintain a radius of the re-selection area above or below a threshold.
32. The non-transitory computer-readable medium of claim 31 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the macro eNode B.
33. The non-transitory computer-readable medium of claim 31 , wherein the path loss and the updated path loss correspond to a path extending between the HeNB and the UE.
34. The non-transitory computer-readable medium of claim 31 , wherein the instructions to adjust the HeNB pilot power level to maintain the re-selection area around the HeNB include instructions to:
adjust the HeNB pilot power level to maintain a radius of the re-selection area within a range.
35. The non-transitory computer-readable medium of claim 31 , wherein the instructions to adjust the HeNB pilot power level to maintain the re-selection area around the HeNB include instructions to:
reduce the HeNB pilot power level to compensate for the updated path loss being less than the path loss.
36. The non-transitory computer-readable medium of claim 31 , wherein the instructions to adjust the HeNB pilot power level to maintain the re-selection area around the HeNB include instructions to:
increase the HeNB pilot power level to compensate for the updated path loss being greater than the path loss.
37. The non-transitory computer-readable medium of claim 31 , wherein the instructions to adjust the HeNB pilot power level to maintain the re-selection area around the HeNB include instructions to:
adjust the HeNB pilot power level in accordance with the following equation:
Pr ,UE= Pcsg ,pilot− Pcsg ,losses( r )−Pen B ,interference( d ),
where Pr,UE is a receive power of the UE, Pcsg,pilot is the pilot transmit power of an HeNB, Pcsg,losses(r) is a path loss from the HeNB to the UE at a distance r, and PenB,interference(d) is an interference caused by the eNodeB at a distance d from the HeNB.