# US 2019/0357221 A1 · Reduced csi (channel state information)-rs (reference signal) density support for fd (full dimensional)-mimo (multiple input multiple output) systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0357221 A1 - Document ID: US20190357221A1 - Status: Published application - Kind: A1 - Application number: 16/467,566 - Filed: 2017-09-19 - Published: 2019-11-21 - Earliest claimed: 2016-09-21 - Assignees: Intel Corporation - Applicants: Intel Corporation - Inventors: Alexei Davydov; Gregory V Morozov; Sameer Pawar - Web page: https://patentgrep.com/patent/US20190357221A1 ## CPC - H04B 7/0613: {using simultaneous transmission (H04B7/0686 takes precedence)} - H04W 72/541: using the level of interference - H04B 17/336: Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] - H04J 13/16: Code allocation - H04L 5/0048: {Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091)} - H04L 5/005: {of common pilots, i.e. pilots destined for multiple users or terminals} - H04L 5/0064: {Rate requirement of the data, e.g. scalable bandwidth, data priority} - H04W 72/046: {the resource being in the space domain, e.g. beams} - H04B: TRANSMISSION - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Techniques discussed herein can facilitate reduced density CSI (Channel State Information)-RS (Reference Signals). One example embodiment can be employed at a UE (User Equipment) and can comprise processing circuitry configured to: process one or more configuration messages that comprise one or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS, wherein the one or more configuration parameters indicate a PRB (Physical Resource Block) decimation and a PRB offset; determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the one or more configuration parameters; measure the reduced density CSI-RS from the set of REs to determine one or more CSI parameters. ## Claims ### Claim at position 1 1-30. (canceled) ### Claim 31 An apparatus configured to be employed in a UE (User Equipment), comprising: a memory interface; and processing circuitry configured to: process one or more configuration messages that comprise one or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS, wherein the one or more configuration parameters indicate a PRB (Physical Resource Block) decimation and a PRB offset; determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the one or more configuration parameters; measure the reduced density CSI-RS from the set of REs to determine one or more CSI parameters; and send the PRB decimation and the PRB offset to a memory via the memory interface. ### Claim 32 (depends on 31) The apparatus of claim 31, wherein the one or more configuration parameters comprises a single configuration parameter that indicates the PRB decimation and the PRB offset. ### Claim 33 (depends on 31) The apparatus of claim 31, wherein the one or more configuration parameters comprise the PRB decimation and the PRB offset. ### Claim 34 (depends on 33) The apparatus of claim 33, wherein the one or more configuration messages comprise a RRC (Radio Resource Control) message that comprises the PRB decimation and a DCI (Downlink Control Information) message that comprises the PRB offset. ### Claim 35 (depends on 31) The apparatus of claim 31, wherein the one or more configuration messages comprises a RRC (Radio Resource Control) message. ### Claim 36 (depends on 31) The apparatus of claim 31, wherein the one or more configuration messages comprises a DCI (Downlink Control Information) message. ### Claim 37 (depends on 31) The apparatus of claim 31, wherein the one or more CSI-RS APs comprise a single CSI-RS AP. ### Claim 38 (depends on 31) The apparatus of claim 31, wherein the one or more CSI-RS APs comprise two or more CSI-RS APs in a CSI-RS group. ### Claim 39 (depends on 38) The apparatus of claim 38, wherein the two or more CSI-RS APs in the CSI-RS group comprise a first half of configured CSI-RS APs for the UE or a second half of configured CSI-RS APs for the UE. ### Claim 40 (depends on 31) The apparatus of claim 31, wherein the one or more CSI-RS APs comprise each CSI-RS AP of a CSI-RS resource configuration. ### Claim 41 An apparatus configured to be employed in a gNB (next Generation Node B), comprising: a memory interface; and processing circuitry configured to: generate one or more configuration messages that comprise one or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS, wherein the one or more configuration parameters indicate a PRB (Physical Resource Block) decimation and a PRB offset; determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the one or more configuration parameters; map the reduced density CSI-RS for the one or more CSI-RS APs to the determined set of REs; and send the PRB decimation and the PRB offset to a memory via the memory interface. ### Claim 42 (depends on 41) The apparatus of claim 41, wherein the one or more configuration parameters comprises a single configuration parameter that indicates the PRB decimation and the PRB offset. ### Claim 43 (depends on 41) The apparatus of claim 41, wherein the one or more configuration parameters comprise the PRB decimation and the PRB offset. ### Claim 44 (depends on 43) The apparatus of claim 43, wherein the one or more configuration messages comprise a RRC (Radio Resource Control) message that comprises the PRB decimation and a DCI (Downlink Control Information) message that comprises the PRB offset. ### Claim 45 (depends on 41) The apparatus of claim 41, wherein the one or more configuration messages comprises a RRC (Radio Resource Control) message. ### Claim 46 (depends on 41) The apparatus of claim 41, wherein the one or more configuration messages comprises a DCI (Downlink Control Information) message. ### Claim 47 (depends on 41) The apparatus of claim 41, wherein the one or more CSI-RS APs comprise a single CSI-RS AP. ### Claim 48 (depends on 41) The apparatus of claim 41, wherein the one or more CSI-RS APs comprise two or more CSI-RS APs in a CSI-RS group. ### Claim 49 (depends on 48) The apparatus of claim 48, wherein the two or more CSI-RS APs in the CSI-RS group comprise a first half of configured CSI-RS APs for the UE or a second half of configured CSI-RS APs for the UE. ### Claim 50 (depends on 41) The apparatus of claim 41, wherein the one or more CSI-RS APs comprise each CSI-RS AP of a CSI-RS resource configuration. ### Claim 51 (depends on 41) The apparatus of claim 41, wherein the processing circuitry is further configured to map PDSCH (Physical Downlink Shared Channel) around the reduced density CSI-RS based on an assumption of a non-reduced density CSI-RS corresponding to the reduced density CSI-RS. ### Claim 52 (depends on 41) The apparatus of claim 41, wherein the processing circuitry is further configured to perform collision handling between the reduced density CSI-RS and at least one of paging messages or broadcast messages based on an assumption of a non-reduced density CSI-RS corresponding to the reduced density CSI-RS. ### Claim 53 (depends on 41) The apparatus of claim 41, wherein the processing circuitry is further configured to renumber the one or more CSI-RS APs such that the processing circuitry is configured to map the reduced density CSI-RS for each CSI-RS AP to a first RE of an associated RE pair of an associated CDM (Code Division Multiplexing) group and to map, to a second RE of the associated RE pair of the associated CDM group, the reduced density CSI-RS for an additional CSI-RS AP, wherein that CSI-RS AP and the additional CSI-RS AP are both associated with a common beam, wherein that CSI-RS is associated with a first polarization of the common beam and the additional CSI-RS AP is associated with a distinct second polarization of the common beam. ### Claim 54 A non-transitory machine readable medium comprising instructions that, when executed, cause a User Equipment (UE) to: receive one or more configuration messages that comprise one or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS, wherein the one or more configuration parameters indicate a PRB (Physical Resource Block) decimation and a PRB offset; determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the one or more configuration parameters; receive the reduced density CSI-RS from the set of REs; and measure the reduced density CSI-RS to determine one or more CSI parameters. ### Claim 55 (depends on 54) The machine readable medium of claim 54, wherein the one or more configuration parameters comprises a single configuration parameter that indicates the PRB decimation and the PRB offset. ### Claim 56 (depends on 54) The machine readable medium of claim 54, wherein the one or more configuration parameters comprise the PRB decimation and the PRB offset. ### Claim 57 A non-transitory machine readable medium comprising instructions that, when executed, cause a next Generation Node B (gNB) to: transmit one or more configuration messages that comprise one or more configuration parameters for one or more CSI (Channel State Information)-RS (Reference Signal) APs (Antenna Ports) of a reduced density CSI-RS, wherein the one or more configuration parameters indicate a PRB (Physical Resource Block) decimation and a PRB offset; determine a set of REs (Resource Elements) for the one or more CSI-RS APs of the reduced density CSI-RS based on the one or more configuration parameters; and transmit the reduced density CSI-RS for the one or more CSI-RS APs via the determined set of REs. ### Claim 58 (depends on 57) The machine readable medium of claim 57, wherein the one or more configuration parameters comprises a single configuration parameter that indicates the PRB decimation and the PRB offset. ### Claim 59 (depends on 57) The machine readable medium of claim 57, wherein the one or more configuration parameters comprise the PRB decimation and the PRB offset. ### Claim 60 (depends on 57) The machine readable medium of claim 57, wherein the instructions, when executed, further cause the gNB to: renumber the one or more CSI-RS APs; map the reduced density CSI-RS for each CSI-RS AP to a first RE of an associated RE pair of an associated CDM (Code Division Multiplexing) group and map, to a second RE of the associated RE pair of the associated CDM group, the reduced density CSI-RS for an additional CSI-RS AP, wherein that CSI-RS AP and the additional CSI-RS AP are both associated with a common beam, wherein that CSI-RS is associated with a first polarization of the common beam and the additional CSI-RS AP is associated with a distinct second polarization of the common beam.