Computing channel state information in a 5G wireless communication system in 4G spectrum frequencies
The described technology is generally directed towards providing a more accurate channel state information (CSI) based on obtaining information at a user equipment as to whether multiple access technologies (e.g., new radio (NR) and long term evolution (LTE)) are multiplexed on the same carrier or not, e.g., whether LTE-NR coexistence is in use. If so, the user equipment removes LTE resource overhead data and NR overhead data when computing the CSI report. If not, the user equipment removes NR overhead data when computing the CSI report. Also described is generating the CSI report based on mutual information or capacity approaches.
1. A method, comprising:
obtaining, by a user equipment comprising a processor, information that indicates that network equipment is using long term evolution communications in a cell in which the user equipment is operating with new radio communications;
in response to obtaining the information that indicates that the network equipment is using long term evolution communications,
obtaining long term evolution resource overhead data corresponding to long term evolution signals, comprising predicting the long term evolution resource overhead data resulting from the long term evolution signals in an orthogonal frequency division multiplexing time-frequency grid;
obtaining new radio resource overhead data corresponding to new radio signals based on network-configured new radio parameter data; and
determining channel state information reference resources based on removing the long term evolution resource overhead data and the new radio resource overhead data from channel state information computation data, wherein the determining comprises computing a link-quality metric, using the link-quality metric to obtain a precoding matrix indicator and a rank indicator, and estimating a channel quality indicator based on the precoding matrix indicator and the rank indicator.
2. The method of claim 1 , wherein obtaining the information that indicates that the network equipment is using long term evolution communications comprises communicating with the network equipment.
3. The method of claim 1 , wherein obtaining the information that indicates that the network equipment is using long term evolution communications comprises detecting that the network equipment has configured the user equipment with rate matching patterns for avoidance of interference between long term evolution traffic and new radio traffic.
4. The method of claim 1 , wherein obtaining the information that indicates that the network equipment is using long term evolution communications comprises processing a broadcast channel message that indicates that long term evolution transmissions are likely present on a carrier according to a likelihood criterion.
5. The method of claim 1 , wherein obtaining the information that indicates that the network equipment is using long term evolution communications comprises detecting physical control format indicator channel signals corresponding to long term evolution signals at a long term evolution component of the user equipment, and based on the detecting the physical control format indicator channel signals, communicating information from the long term evolution component to a new radio component of the user equipment that indicates that long term evolution is in use.
6. The method of claim 1 , wherein obtaining the information that indicates that the network equipment is using long term evolution communications comprises detecting reference signals corresponding to long term evolution signals at a long term evolution component of the user equipment, and based on the detecting the reference signals, communicating information from the long term evolution component to a new radio component of the user equipment that indicates that long term evolution is in use.
7. The method of claim 1 , wherein obtaining the information that indicates that the network equipment is using long term evolution communications comprises determining that a frequency band in which the user equipment is operating is a frequency band defined to support long term evolution-new radio coexistence.
8. The method of claim 1 , wherein obtaining the information that indicates that the network equipment is using long term evolution communications comprises analyzing a detected subcarrier spacing in a synchronization signal block and a time-domain mapping pattern.
9. The method of claim 8 , wherein the analyzing comprises determining that a symbol offset relative to a frame boundary as defined by a time-domain mapping pattern for the cell indicates that long term evolution-new radio coexistence is deployed for at least one frequency band used by the cell.
10. The method of claim 1 , wherein the determining further comprises using mutual information to compute the link-quality metric.
11. The method of claim 1 , wherein the determining further comprises using a capacity computation to compute the link-quality metric.
12. A user equipment, comprising:
a processor; and
a memory that stores executable instructions that, when executed by the processor, facilitate performance of operations, the operations comprising:
obtaining information at a new radio component indicating whether long term evolution-new radio coexistence is in use in a cell in which the user equipment is operating;
determining, based on the information, whether long term evolution-new radio coexistence is in use;
in response to determining that long term evolution-new radio coexistence is in use,
obtaining first overhead data corresponding to long term evolution signals and new radio signals, and
determining channel state information reference resources based on removing the first overhead data of the long term evolution signals and new radio signals from channel state information computation data, wherein the determining comprises computing a link-quality metric, using the link-quality metric to obtain a precoding matrix indicator and a rank indicator, and estimating a channel quality indicator based on the precoding matrix indicator and the rank indicator; and
in response to determining that long term evolution-new radio coexistence is not in use,
obtaining second overhead data of new radio signals, and
determining channel state information reference resources by removing the second overhead data of the new radio signals from channel state information computation data.
13. The user equipment of claim 12 , wherein obtaining the information that indicates whether long term evolution-new radio coexistence is in use comprises at least one of: communicating with network equipment, processing a broadcast channel message that indicates whether long term evolution transmissions are present on a carrier, determining a physical downlink control channel starting symbol location, or determining a demodulation reference signal starting symbol location.
14. The user equipment of claim 12 , wherein obtaining the information that indicates whether long term evolution-new radio coexistence is in use comprises at least one of: determining that a frequency band in which the user equipment is operating is a frequency band defined to support long term evolution-new radio coexistence, or analyzing a detected subcarrier spacing in a synchronization signal block and a time-domain mapping pattern.
15. The user equipment of claim 14 , wherein obtaining the information that indicates whether long term evolution-new radio coexistence is in use further comprises determining that a symbol offset relative to a frame boundary as defined by a time-domain mapping pattern for the cell indicates that long term evolution-new radio coexistence is deployed for at least one frequency band used by the cell.
16. The user equipment of claim 12 , wherein obtaining the information that indicates whether long term evolution-new radio coexistence is in use comprises detecting that network equipment has configured the user equipment with a rate matching pattern to avoid interference between long term evolution traffic and new radio traffic.
17. The user equipment of claim 12 , wherein obtaining the information that indicates whether long term evolution-new radio coexistence is in use comprises deriving long term evolution overhead data based on configured long term evolution parameters.
18. A non-transitory machine-readable medium, comprising executable instructions that, when executed by a processor of a radio user equipment, facilitate performance of operations, the operations comprising:
obtaining information at a new radio component indicating whether long term evolution communication is in use in a cell in which the radio user equipment is operating with new radio communications;
deciding, based on the information, whether long term evolution communication is in use;
in response to deciding that long term evolution communication is in use, obtaining long term evolution resource overhead data corresponding to long term evolution signals, comprising predicting the long term evolution resource overhead data resulting from long term evolution signals in an orthogonal frequency division multiplexing time-frequency grid, obtaining new radio resource overhead data corresponding to new radio signals based on network-configured new radio parameter data, and computing channel state information reference resources based on removing the long term evolution resource overhead data and the new radio resource overhead data from channel state information computation data at least in part by computing a link-quality metric, using the link-quality metric to obtain a precoding matrix indicator and a rank indicator, and estimating a channel quality indicator based on the precoding matrix indicator and the rank indicator;
in response to deciding that long term evolution communication is not in use, obtaining new radio resource overhead data corresponding to new radio signals based on network-configured new radio parameter data and computing channel state information reference resources based on removing the new radio resource overhead data from channel state information computation data; and
transmitting a channel state information report based on the computing the channel state information reference resources to network equipment corresponding to the cell.
19. The non-transitory machine-readable medium of claim 18 , wherein obtaining the information that indicates whether long term evolution communication is in use comprises detecting that the network equipment has configured the user equipment with a rate matching pattern for avoiding interference between long term evolution traffic and new radio traffic.
20. The non-transitory machine-readable medium of claim 18 , wherein obtaining the information that indicates whether long term evolution communication is in use comprises deriving long term evolution overhead data based on configured long term evolution parameters.