Devices, systems and methods for power efficient beam management in wireless systems
A wireless transmit/receive unit (WTRU) is configured to receive a radio resource control (RRC) message. The RRC message may comprise information that indicates an association between each of a plurality of beams and power information. The WTRU is configured to receive a trigger message. The WTRU is configured to select a beam in response to the received trigger message. The WTRU is configured to send a control channel transmission using a power level. The power level may be based on the power information mapped to the selected beam.
1. A wireless transmit/receive unit (WTRU) comprising:
a transceiver; and
a processor, wherein:
the transceiver is configured to receive a radio resource control (RRC) message, wherein the RRC message comprises information that indicates an association between each of a plurality of beams and power information;
the transceiver is further configured to receive a trigger message;
the processor is configured to select a beam in response to the received trigger message; and
the transceiver is further configured to send a control channel transmission using a power level, wherein the power level is based on the power information associated with the selected beam.
2. The WTRU of claim 1 , wherein the selected beam is associated with a reference signal (RS).
3. The WTRU of claim 2 , wherein the RS is a channel state information (CSI)-RS or a synchronization RS.
4. The WTRU of claim 1 , wherein the transceiver is further configured to transmit, prior to the reception of the trigger message, a second control channel transmission using a power level based on power information not associated with a beam.
5. The WTRU of claim 1 , wherein the power information is associated with closed loop power control.
6. The WTRU of claim 1 , wherein the power information is associated with open loop power control.
7. The WTRU of claim 1 , wherein the control channel transmission includes feedback information and uplink reference signals.
8. The WTRU of claim 1 , wherein the processor is further configured to select, on a condition that a first beam fails, a backup beam.
9. The WTRU of claim 1 , wherein a transition from one beam to another beam is based on a beam management algorithm.
10. A method for use by a wireless transmit/receive unit (WTRU), the method comprising:
receiving a radio resource control (RRC) message, wherein the RRC message comprises information that indicates an association between each of a plurality of beams and power information;
receiving a trigger message;
selecting a beam in response to the received trigger message; and
sending a control channel transmission using a power level, wherein the power level is based on the power information associated with the selected beam.
11. The method of claim 10 , wherein the selected beam is associated with a reference signal (RS).
12. The method of claim 11 , wherein the RS is a channel state information (CSI)-RS or a synchronization RS.
13. The method of claim 10 , further comprising:
transmitting, prior to the reception of the trigger message, a second control channel transmission using a power level based on power information not associated with a beam.
14. The method of claim 10 , wherein the power information is associated with closed loop power control.
15. The method of claim 10 , wherein the power information is associated with open loop power control.
16. The method of claim 10 , wherein the control channel transmission includes feedback information and uplink reference signals.
17. The method of claim 10 , further comprising:
selecting, on a condition that a first beam fails, a backup beam.
18. The method of claim 10 , wherein a transition from one beam to another beam is based on a beam management algorithm.