Receiving messages in connection with LTE wakeup
In some implementations, a method for managing a receiver for user equipment in a Long Term Evolution (LTE) system includes receiving, when in a DRX state or sub-state, a message within a Physical Downlink Control Channel (PDCCH) resource region of a first sub-frame. The message is associated with a PDSCH transmission in a second sub-frame different from the first sub-frame. When not in the DRX state or sub-state, a message is received within a Physical Downlink Control Channel (PDCCH) resource region of a first sub-frame. The message associated with a PDSCH transmission in the first sub-frame.
1. A method for managing a receiver for user equipment in a Long Term Evolution (LTE) system, comprising:
receiving a command from an eNodeB (eNB) to transition to a discontinuous reception (DRX) state or sub-state, the DRX state or sub-state comprising a set of defined sub-frame instances during which the UE is required to receive between one and four Orthogonal Frequency Division Multiplexing (OFDM) symbols within a Physical Downlink Control Channel (PDCCH) resource region but is not required to receive signals within a Physical Downlink Shared Channel (PDSCH) resource region; and, subsequent to receiving the command:
receiving, when in the DRX state or sub-state, a message within a PDCCH resource region of a first sub-frame, the message associated with a transmission in a second sub-frame different from the first sub-frame; and
receiving, when not in the DRX state or sub-state, a message within a PDCCH resource region of a first sub-frame, the message associated with a PDSCH transmission in the first sub-frame.
2. The method of claim 1 , the method further comprising:
decoding, when in the DRX state or sub-state, the PDCCH resource region of the first sub-frame to identify a wake-up message for the UE, the wake-up message configured to activate the UE receiver in the second sub-frame; and
activating the UE receiver during the second sub-frame.
3. The method of claim 2 , wherein activating the UE receiver during the second sub-frame includes activating the receiver for at least a portion of a PDCCH resource region of the second sub-frame.
4. The method of claim 2 , wherein activating the UE receiver during the second sub-frame includes activating the receiver for at least a portion of a PDSCH resource region of the second sub-frame.
5. The method of claim 2 , wherein activating the UE receiver during the second sub-frame includes activating the receiver for at least a portion of a PDCCH resource region of the second sub-frame and for at least a portion of a PDSCH region of the second sub-frame.
6. The method of claim 2 , wherein the wake-up message contains information relating to a number of sub-frame durations between the first and second sub-frames.
7. The method of claim 1 , wherein the message received in the DRX state or sub-state within the PDCCH resource region of the first sub-frame is conveyed using at least one of a Downlink Control Information (DCI) format 1C or 3/3A.
8. The method of claim 1 , further comprising transmitting, prior to receiving the command, a request to the eNB to transition to the DRX state or sub-state in response to the UE identifying a trigger event.
9. The method of claim 1 , wherein the UE receives the command independent of initially transmitting a request to the eNB.
10. The method of claim 1 , further comprising transmitting, to the eNB, an acknowledgement indicating a transition to the DRX state or sub-state.
11. The method of claim 1 , further comprising determining that the message received in the DRX state or sub-state within the PDCCH resource region of the first sub-frame communicates at least a Radio Network Temporary Identifier (RNTI) associated at least with the UE.
12. The method of claim 11 , wherein the RNTI is indicative of a number of wake-up indicators included in the message.
13. The method of claim 11 , wherein the Radio Network Temporary Identifier (RNTI) is a C-RNTI.
14. The method of claim 11 , wherein the Radio Network Temporary Identifier (RNTI) is associated with a group of UEs including the UE.
15. The method of claim 11 , further comprising, determining the presence of the message communicating the RNTI, decoding a wake-up indicator communicated within the message, and determining that the wake-up indicator is set to a positive wake-up value for the UE.
16. The method of claim 15 , wherein the wake-up indicator set to a positive wake-up value is a downlink or uplink assignment message.
17. The method of claim 15 , wherein decoding the wake-up indicator comprises:
decoding the message to identify a codeword and
decoding the codeword using an algorithm assigned to the UE.
18. User Equipment (UE) for managing a UE receiver in a Long Term Evolution (LTE) system, comprising:
one or more processors configure to:
receive a command from an eNodeB (eNB) to transition to a discontinuous reception (DRX) state or sub-state, the DRX state or sub-state comprising a set of defined sub-frame instances during which the UE is required to receive between one and four Orthogonal Frequency Division Multiplexing (OFDM) symbols within a Physical Downlink Control Channel (PDCCH) resource region but is not required to receive signals within a Physical Downlink Shared Channel (PDSCH) resource region; and, subsequent to receiving the command:
receive, when in the DRX state or sub-state, a message within a PDCCH resource region of a first sub-frame, the message associated with a transmission in a second sub-frame different from the first sub-frame; and
receive, when not in the DRX state or sub-state, a message within a Physical Downlink Control Channel (PDCCH) resource region of a first sub-frame, the message associated with a PDSCH transmission in the first sub-frame.
19. The UE of claim 18 , the processors further configured to:
decode, when in the DRX state or sub-state, the PDCCH resource region of the first sub-frame to identify a wake-up message for the UE, the wake-up message configured to activate the UE receiver in the second sub-frame; and
activate the UE receiver during the second sub-frame.
20. The UE of claim 19 , wherein the processors configured to activate the UE receiver during the second sub-frame includes the processors configured to activate the receiver for at least a portion of a PDCCH resource region of the second sub-frame.
21. The UE of claim 19 , wherein the processors configured to activate the UE receiver during the second sub-frame includes the processors configured to activate the receiver for at least a portion of a PDSCH resource region of the second sub-frame.
22. The UE of claim 19 , wherein the processors configured to activate the UE receiver during the second sub-frame includes the processors configured to activate the receiver for at least a portion of a PDCCH resource region of the second sub-frame and for at least a portion of a PDSCH region of the second sub-frame.
23. The UE of claim 19 , wherein the wake-up message contains information relating to a number of sub-frame durations between the first and second sub-frames.
24. The UE of claim 18 , wherein the message received in the DRX state or sub-state within the PDCCH resource region of the first sub-frame is conveyed using at least one of a Downlink Control Information (DCI) format 1C or 3/3A.
25. The UE of claim 18 , the processors further configured to transmit, prior to receiving the command, a request to the eNB to transition to the DRX state or sub-state in response to the UE identifying a trigger event.
26. The UE of claim 18 , wherein the UE receives the command independent of initially transmitting a request to the eNB.
27. The UE of claim 18 , the processors further configured to transmit, to the eNB, an acknowledgement indicating a transition to the DRX state or sub-state.
28. The UE of claim 18 , the processors further configured to determine that the message received in the DRX state or sub-state within the PDCCH resource region of the first sub-frame communicates at least a Radio Network Temporary Identifier (RNTI) associated with at least the UE.
29. The UE of claim 28 , wherein the RNTI is indicative of a number of wake-up indicators included in the message.
30. The UE of claim 28 , wherein the Radio Network Temporary Identifier (RNTI) is a C-RNTI.
31. The UE of claim 28 , wherein the Radio Network Temporary Identifier (RNTI) is associated with a group of UEs including the UE.
32. The UE of claim 28 , the processors further configured to determine the presence of the message communicating the RNTI, decoding a wake-up indicator communicated within the message, and determining that the wake-up indicator is set to a positive wake-up value for the UE.
33. The UE of claim 32 , wherein the wake-up indicator set to a positive wake-up value is a downlink or uplink assignment message.
34. The UE of claim 32 , wherein decoding the wake-up indicator comprises:
decode the message to identify a codeword and
decode the codeword using an algorithm assigned to the UE.