Alleviating Mobile Device Overload Conditions in a Mobile Communication System

• US 20090215442A1
• Filed: 09/26/2008
• Published: 08/27/2009
• Est. Priority Date: 02/25/2008
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Wilde, Andreas, Palenius, Torgny, Lindoff, Bengt, Bernhardsson, Bo, Nilsson, Johan, Anzill, Werner
• Granted Patent: US 8,086,229 B2
• Time in Patent Office: Days
• US Class Current: 455/423
• CPC Class Codes: H04B 1/036 Cooling arrangements
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0028 Formatting
• CPC Class Codes: H04L 1/0031 Multiple signaling transmission H04L1/1664, F15 take precedence
• CPC Class Codes: H04L 1/0036 arrangements specific to the receiver
• CPC Class Codes: H04L 1/1607 Details of the supervisory signal
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/52 based on load

Abstract

A user equipment (UE) in a mobile communications system is operated in a manner that alleviates or avoids an overload condition in the UE. This involves operating a receiver of the UE to receive one or more data blocks via a channel. In response to a user equipment overload condition being detected, a channel quality indicator (CQI) value is reported to a serving base station, wherein the reported CQI value represents a channel quality that is lower than an actual quality of the channel. The UE is then operated in a manner that is consistent with the reported CQI value. UE overload conditions include overheating, and an inability to process received data blocks at the rate at which they are being received.

Claims

1. A method of operating a user equipment in a mobile communications system, the method comprising:

operating a receiver of the user equipment to receive one or more data blocks via a channel;

detecting a user equipment overload condition;

in response to the detected user equipment overload condition, reporting a channel quality indicator (CQI) value to a serving base station, wherein the reported CQI value represents a channel quality that is lower than an actual quality of the channel;

operating the user equipment in a manner that is consistent with the reported CQI value.

2. The method of claim 1, comprising:

sending negative acknowledgements (NAKs) to the serving base station at a rate that is consistent with operation by means of a channel having a quality that corresponds to the reported CQI value, including sending one or more NAKs in response to acceptable reception of one or more data blocks.

3. The method of claim 2, wherein sending NAKs to the serving base station at the rate that is consistent with operation by means of the channel having the quality that corresponds to the reported CQI value is further performed in a manner such that the NAKs are distributed over time in a way that emulates a distribution of NAKs that corresponds to the channel having the quality that corresponds to the reported CQI value.

4. The method of claim 3, wherein the distribution of sent NAKs over time is a random or pseudorandom distribution.

5. The method of claim 1, wherein the reported CQI value is selected by determining which of a plurality of candidate CQI values will cause the user equipment to maintain as much functionality as possible while at the same time alleviating or avoiding the user equipment overload condition.

6. The method of claim 1, wherein the user equipment overload condition is an overheating condition.

7. The method of claim 1, wherein the user equipment overload condition is a limitation in user equipment processing capability.

8. The method of claim 7, wherein the limitation in user equipment processing capability is a receiving buffer bottleneck.

9. The method of claim 7, wherein the limitation in user equipment processing capability is a transmitting buffer bottleneck.

10. The method of claim 7, wherein the limitation in user equipment processing capability is a signal processing bottleneck.

11. The method of claim 7, wherein the limitation in user equipment processing capability is an inability to process received data blocks at an instantaneous downlink throughput rate.

12. The method of claim 1, wherein the user equipment overload condition is an alert that an actual overload condition will exist if the user equipment continues operating in a present manner of operation.

13. A method of operating a user equipment in a mobile communications system, the method comprising:

operating a receiver of the user equipment to receive one or more data blocks via a channel;

detecting a user equipment overload condition;

in response to the detected user equipment overload condition, sending a signal to a serving base station, wherein the signal is a request for the serving base station to reduce a downlink data throughput rate, and wherein the signal comprises a first field for indicating whether a downlink data throughput rate reduction is being requested, and a second field that indicates how the serving base station should respond when the downlink data throughput rate reduction is being requested.

14. The method of claim 13, wherein the second field is a channel quality indicator (CQI) field when the downlink data throughput rate reduction is not being requested.

15. The method of claim 13, wherein the second field indicates by how much the downlink data throughput rate should be reduced.

16. The method of claim 13, wherein the second field indicates a maximum data rate value that the user equipment is able to handle.

17. An apparatus for operating a user equipment in a mobile communications system, the apparatus comprising:

logic configured to operate a receiver of the user equipment to receive one or more data blocks via a channel;

logic configured to detect a user equipment overload condition;

logic configured to report a channel quality indicator (CQI) value to a serving base station in response to the detected user equipment overload condition, wherein the reported CQI value represents a channel quality that is lower than an actual quality of the channel;

logic configured to operate the user equipment in a manner that is consistent with the reported CQI value.

18. The apparatus of claim 17, comprising:

logic configured to send negative acknowledgements (NAKs) to the serving base station at a rate that is consistent with operation by means of a channel having a quality that corresponds to the reported CQI value, including sending one or more NAKs in response to acceptable reception of one or more data blocks.

19. The apparatus of claim 18, wherein the logic configured to send NAKs to the serving base station at the rate that is consistent with operation by means of the channel having the quality that corresponds to the reported CQI value operates in a manner such that the NAKs are distributed over time in a way that emulates a distribution of NAKs that corresponds to the channel having the quality that corresponds to the reported CQI value.

20. The apparatus of claim 19, wherein the distribution of sent NAKs over time is a random or pseudorandom distribution.

21. The apparatus of claim 17, wherein the logic configured to report the CQI value to the serving base station in response to the detected user equipment overload condition selects the reported CQI value by determining which of a plurality of candidate CQI values will cause the user equipment to maintain as much functionality as possible while at the same time alleviating or avoiding the user equipment overload condition.

22. The apparatus of claim 17, wherein the user equipment overload condition is an overheating condition.

23. The apparatus of claim 17, wherein the user equipment overload condition is a limitation in user equipment processing capability.

24. The apparatus of claim 23, wherein the limitation in user equipment processing capability is a receiving buffer bottleneck.

25. The apparatus of claim 23, wherein the limitation in user equipment processing capability is a transmitting buffer bottleneck.

26. The apparatus of claim 23, wherein the limitation in user equipment processing capability is a signal processing bottleneck.

27. The apparatus of claim 23, wherein the limitation in user equipment processing capability is an inability to process received data blocks at an instantaneous downlink throughput rate.

28. The apparatus of claim 17, wherein the user equipment overload condition is an alert that an actual overload condition will exist if the user equipment continues operating in a present manner of operation.

29. An apparatus for operating a user equipment in a mobile communications system, the apparatus comprising:

logic configured to operate a receiver of the user equipment to receive one or more data blocks via a channel;

logic configured to detect a user equipment overload condition;

logic configured to send a signal to a serving base station in response to the detected user equipment overload condition, wherein the signal is a request for the serving base station to reduce a downlink data throughput rate, and wherein the signal comprises a first field for indicating whether a downlink data throughput rate reduction is being requested, and a second field that indicates how the serving base station should respond when the downlink data throughput rate reduction is being requested.

30. The apparatus of claim 29, wherein the second field is a channel quality indicator (CQI) field when the downlink data throughput rate reduction is not being requested.

31. The apparatus of claim 29, wherein the second field indicates by how much the downlink data throughput rate should be reduced.

32. The apparatus of claim 29, wherein the second field indicates a maximum data rate value that the user equipment is able to handle.