Power headroom reporting and channel state information reporting for energy harvesting devices
Methods, systems, and devices for wireless communication are described. An energy harvesting wireless device may accumulate energy during an energy harvesting state for use in subsequent operation. In some cases, the energy harvesting wireless device may detect a trigger, such as a change in an energy status of the energy harvesting wireless device or explicit control signaling from a network, for transmitting a power headroom report (PHR), channel state information (CSI), or both. The energy harvesting wireless device may transmit the message including one or more of the PHR or the CSI and indicating that energy information (e.g., an energy report, an energy request, or both) is multiplexed with the PHR, the CSI, or both. In some cases, the message may include control information such as a medium access control (MAC) control element (MAC-CE).
1 . An apparatus for wireless communication at an energy harvesting wireless device, comprising:
at least one processor; and
memory coupled with the at least one processor, the memory storing instructions for the at least one processor to cause the energy harvesting wireless device to:
detect a trigger for transmitting one or more of a power headroom report or channel state information; and
transmit a message comprising one or more of the power headroom report or the channel state information, wherein the message comprises an indication that energy information for the energy harvesting wireless device is multiplexed with one or more of the power headroom report or the channel state information.
2 . The apparatus of claim 1 , wherein the instructions to transmit the message are for the at least one processor to cause the energy harvesting wireless device to:
transmit, via the message, control information that indicates the power headroom report, wherein one or more reserved bits of the control information indicate a type of the power headroom report.
3 . The apparatus of claim 2 , wherein the control information comprises a first set of one or more bits that indicate the power headroom report and a second set of one or more bits that indicate an energy request, the energy information, or both, wherein the second set of one or more bits comprises the one or more reserved bits.
4 . The apparatus of claim 2 , wherein a first reserved bit of the one or more reserved bits indicates an energy request and a second reserved bit of the one or more reserved bits indicates the energy information.
5 . The apparatus of claim 4 , wherein the energy request comprises a request for additional energy, and the energy information indicates an energy charging status.
6 . The apparatus of claim 1 , wherein the instructions to transmit the message are for the at least one processor to cause the energy harvesting wireless device to:
transmit, via the message, control information that comprises a first set of one or more reserved bits, a second set of one or more bits that indicate an energy request, the energy information, or both, and a third set of one or more bits that indicate the power headroom report.
7 . The apparatus of claim 1 , wherein the instructions to transmit the message are for the at least one processor to cause the energy harvesting wireless device to:
transmit, via the message, control information that comprises a first set of one or more reserved bits, a second set of one or more bits that indicate an energy request, the energy information, or both, and a third set of one or more bits that indicate the channel state information.
8 . The apparatus of claim 1 , wherein the instructions to transmit the message are for the at least one processor to cause the energy harvesting wireless device to:
transmit, via the message, control information that indicates the power headroom report, wherein a reserved bit of the control information indicates that the energy information is multiplexed with the power headroom report.
9 . The apparatus of claim 1 , wherein the instructions to transmit the message are for the at least one processor to cause the energy harvesting wireless device to:
transmit, via the message, control information that comprises a first set of one or more bits that indicates a rank indicator associated with the channel state information, a second set of one or more bits that indicates a channel quality indicator associated with the channel state information, and a third set of one or more bits that indicates an energy request, the energy information, or both.
10 . The apparatus of claim 1 , wherein the instructions to detect the trigger are for the at least one processor to cause the energy harvesting wireless device to:
detect one or more changes in the energy information that trigger transmission of the message, wherein the one or more changes are associated with a discharging rate, a charging rate, a pathloss, or any combination thereof.
11 . The apparatus of claim 1 , wherein the instructions to detect the trigger are for the at least one processor to cause the energy harvesting wireless device to:
detect a change in a discharging rate below a threshold value, a change in a charging rate above or below a threshold value, or both, wherein a pathloss is unchanged, and wherein the changes trigger transmission of the message.
12 . The apparatus of claim 1 , wherein the instructions to transmit the message are for the at least one processor to cause the energy harvesting wireless device to:
transmit, via the message, the power headroom report in accordance with a timer.
13 . The apparatus of claim 1 , wherein the instructions to detect the trigger are for the at least one processor to cause the energy harvesting wireless device to:
receive control signaling that triggers transmission of the message, wherein the control signaling indicates to transmit the power headroom report at a time or during a period of time.
14 . The apparatus of claim 1 , wherein the energy information comprises a charging rate profile, a discharging rate profile, an energy level profile, or any combination thereof.
15 . The apparatus of claim 1 , wherein the message comprises a medium access control (MAC) control element (MAC-CE) that indicates one or more of the power headroom report or the channel state information.
16 . A method for wireless communication at an energy harvesting wireless device, comprising:
detecting a trigger for transmitting one or more of a power headroom report or channel state information; and
transmitting a message comprising one or more of the power headroom report or the channel state information, wherein the message comprises an indication that energy information for the energy harvesting wireless device is multiplexed with one or more of the power headroom report or the channel state information.
17 . The method of claim 16 , wherein transmitting the message comprises:
transmitting, via the message, control information that indicates the power headroom report, wherein one or more reserved bits of the control information indicate a type of the power headroom report.
18 . The method of claim 17 , wherein the control information comprises a first set of one or more bits that indicate the power headroom report and a second set of one or more bits that indicate an energy request, the energy information, or both, wherein the second set of one or more bits comprises the one or more reserved bits.
19 . The method of claim 17 , wherein a first reserved bit of the one or more reserved bits indicates an energy request and a second reserved bit of the one or more reserved bits indicates the energy information.
20 . The method of claim 19 , wherein the energy request comprises a request for additional energy, and the energy information indicates an energy charging status.
21 . The method of claim 16 , wherein transmitting the message comprises:
transmitting, via the message, control information that comprises a first set of one or more reserved bits, a second set of one or more bits that indicate an energy request, the energy information, or both, and a third set of one or more bits that indicate the power headroom report.
22 . The method of claim 16 , wherein transmitting the message comprises:
transmitting, via the message, control information that comprises a first set of one or more reserved bits, a second set of one or more bits that indicate an energy request, the energy information, or both, and a third set of one or more bits that indicate the channel state information.
23 . The method of claim 16 , wherein transmitting the message comprises:
transmitting, via the message, control information that indicates the power headroom report, wherein a reserved bit of the control information indicates that the energy information is multiplexed with the power headroom report.
24 . The method of claim 16 , wherein transmitting the message comprises:
transmitting, via the message, control information that comprises a first set of one or more bits that indicates a rank indicator associated with the channel state information, a second set of one or more bits that indicates a channel quality indicator associated with the channel state information, and a third set of one or more bits that indicates an energy request, the energy information, or both.
25 . The method of claim 16 , wherein detecting the trigger comprises:
detecting one or more changes in the energy information that trigger transmission of the message, wherein the one or more changes are associated with a discharging rate, a charging rate, a pathloss, or any combination thereof.
26 . The method of claim 16 , wherein detecting the trigger comprises:
detecting a change in a discharging rate below a threshold value, a change in a charging rate above or below a threshold value, or both, wherein a pathloss is unchanged, and wherein the changes trigger transmission of the message.
27 . The method of claim 16 , wherein transmitting the message comprises:
transmitting, via the message, the power headroom report in accordance with a timer.
28 . The method of claim 16 , wherein detecting the trigger comprises:
receiving control signaling that triggers transmission of the message, wherein the control signaling indicates to transmit the power headroom report at a time or during a period of time.
29 . The method of claim 16 , wherein the energy information comprises a charging rate profile, a discharging rate profile, an energy level profile, or any combination thereof.
30 . The method of claim 16 , wherein the message comprises a medium access control (MAC) control element (MAC-CE) that indicates one or more of the power headroom report or the channel state information.