Apparatus, method, program products for maximizing desired multi-transmission point signal to inter-layer-group-interference via UE beam control
An apparatus is provided that includes at least receiver circuitry, a processor, and memory. The apparatus also includes a plurality of directional antennas configured to simultaneously receive different downlink signals for each polarization. The apparatus further includes control circuitry for controlling processes for beam sweeping, beam refinement, and selecting a beam pair that maximizes signal strength while minimizing inter-layer-group interference. A portable electronic device and a stationary electronic device that include the apparatus are also provided. A method carried out by means, such as the apparatus, is also provided. A computer program product, such as a non-transitory computer readable medium, for causing an apparatus to carry out such a method is also provided.
1 . An apparatus comprising:
at least one processor; and
at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to:
determine that two or more different downlink signals received simultaneously from two or more different transmission points should be received on a single mmWave antenna array module of the apparatus,
wherein respective downlink signals of the two or more different downlink signals comprise one or two layers per signal carrying the transmission configuration indicator, TCI, at least one downlink control information, and one or more channel state information per transmission point, and
wherein respective downlink signals of the two or more different downlink signals further comprise one or more TCIs, respective TCIs having a respective TCI state;
receive, simultaneously, on the single mmWave antenna array module of the apparatus, the two or more different downlink signals from the two or more different transmission points; and
steer one or more receiver spatial filters in order to maximize a signal to inter-layer-group-interference, SILGI, ratio, the SILGI ratio being a ratio of a unique beamforming array, UBA, desired signal to inter-layer-group-interference.
2 . The apparatus of claim 1 , wherein the apparatus is further configured to steer the receiver spatial filters by:
for respective TCI states, performing coarse narrow beam refinement to find angles of arrival, AoAs, that maximize a received signal power, a reference signal received power, RSRP, or a reference signal strength indicator, RSSI, on a respective UBA.
3 . The apparatus of claim 1 , wherein the apparatus is further configured to steer the receiver spatial filter by:
for respective TCI states, performing refined narrow beam refinement to find AoAs that maximize the SILGI ratio while the received signal power, the RSRP, or the RSSI of the downlink signal is maintained above a signal threshold.
4 . The apparatus of claim 1 , wherein the apparatus is further configured to:
determine that the apparatus is configured for reception of simultaneous transmission from multiple transmission points with multiple active TCI states that are not sharing spatial receiver filters at the apparatus.
5 . The apparatus of claim 4 , wherein the apparatus is further configured to:
determine, based on the determination that the apparatus is configured for reception of simultaneous transmission from multiple transmission points with multiple active TCI states that are not configured for sharing spatial receiver filters at the apparatus, multiple downlink control information, DCIs, with full overlapping time and frequency resource elements of a physical downlink shared channel, PDSCH.
6 . The apparatus of claim 1 , wherein the received signal power is equal to or greater than an RSRP threshold.
7 . The apparatus of claim 2 , wherein the apparatus is further configured to perform the coarse narrow beam refinement for each TCI state to find AoAs that maximize at least one of the received signal power, the RSRP, or the RSSI on each UBA, to find the two dual polarized beams with the strongest received signal power, RSRP, or RSSI, via a narrow beam sweep, during one or more of:
aperiodic transmission of non-zero power channel state information reference symbols, NZP-CSI-RS, with repetition being implemented for respective active TCI states, synchronization symbol, SS, bursts, or
cyclic prefix based on beam sweeping during/via a physical downlink shared channel, PDSCH.
8 . The apparatus of claim 3 , wherein the apparatus is further configured to perform the refined narrow beam refinement by:
measuring a desired signal for a first UBA and a second UBA of a same mmWave antenna array module;
measuring inter-layer-group interference, ILGI, for the first UBA and the second UBA of the same mmWave antenna array module; and
calculating the SILGI ratio for the first UBA and the second UBA of the same mmWave antenna array module.
9 . The apparatus of claim 3 , wherein the apparatus is further configured to:
after completing a measurement sequence of a full orthogonal frequency-division multiplexing, OFDM, symbol burst, discard the measurements from the beams that lead to a desired signal level below the signal threshold.
10 . The apparatus of claim 1 , wherein the apparatus is further configured to steer the receiver spatial filter in order to increase the SILGI ratio by:
steering UBA beam 1 away from AoA2 from TCI2; and
steering UBA beam 2 away from AoA1 from TCI1.
11 . The apparatus of claim 1 , wherein the apparatus is configured to:
send, to the network node, an indication for at least each TCI of at least one or more of:
a signal strength of the desired signal, the IGLI, or the SILGI, wherein said indication for each TCI is included in at least one of: uplink control information, an L1 reporting message, or a medium access control, MAC, message.
12 . A method comprising:
determining, at a user equipment, that two or more different downlink signals received simultaneously from two or more different transmission points should be received on a single mmWave antenna array module of the user equipment,
wherein respective downlink signals of the two or more different downlink signals comprise one or two layers per signal carrying the transmission configuration indicator, TCI, at least one downlink control information, and one or more channel state information per transmission point, and
wherein respective downlink signals of the two or more different downlink signals further comprise one or more TCIs, respective TCIs having a respective TCI state;
receiving, simultaneously, on the single mmWave antenna array module of the user equipment, the two or more different downlink signals from the two or more different transmission points; and
steering one or more receiver spatial filters in order to maximize a signal to inter-layer-group-interference, SILGI, ratio, the SILGI ratio being a ratio of a unique beamforming array, UBA, desired signal to inter-layer-group-interference.
13 . The method of claim 12 , wherein the steering the receiver spatial filter comprises:
for respective TCI states, performing coarse narrow beam refinement to find angles of arrival, AoAs, that maximize a received signal power, a reference signal received power, RSRP, or a reference signal strength indicator, RSSI, on a respective UBA.
14 . The method of claim 12 , wherein the steering the receiver spatial filter comprises:
for respective TCI states, performing refined narrow beam refinement to find AoAs that maximize the SILGI ratio while the received signal power, the RSRP, or the RSSI of the downlink signal is maintained above a signal threshold.
15 . The method of claim 12 , further comprising:
determining that the user equipment is configured for reception of simultaneous transmission from multiple transmission points with multiple active TCI states that are not sharing spatial receiver filters at the user equipment.
16 . The method of claim 12 , further comprising:
sending, to the network node, an indication for at least each TCI of at least one or more of: a signal strength of the desired signal, the IGLI, or the SILGI.
17 . The method of claim 16 , wherein at least the indication of one of more of: the strength of the desired signal, the ILGI, or the SILGI for each TCI is included in at least one of: uplink control information, an L1 reporting message, or a medium access control, MAC, message.
18 . A non-transitory storage medium storing program instructions that, when executed by a processor, cause a user equipment at least to:
determine that two or more different downlink signals received simultaneously from two or more different transmission points should be received on a single mmWave antenna array module of the user equipment,
wherein respective downlink signals of the two or more different downlink signals comprise one or two layers per signal carrying the transmission configuration indicator, TCI, at least one downlink control information, and one or more channel state information per transmission point, and
wherein respective downlink signals of the two or more different downlink signals further comprise one or more TCIs, respective TCIs having a respective TCI state;
receive, simultaneously, on the single mmWave antenna array module of the user equipment, the two or more different downlink signals from the two or more different transmission points; and
steer one or more receiver spatial filters in order to maximize a signal to inter-layer-group-interference, SILGI, ratio, the SILGI ratio being a ratio of a unique beamforming array, UBA, desired signal to inter-layer-group-interference.
19 . The non-transitory storage medium of claim 18 , wherein the signal received power is equal to or greater than an RSRP threshold.
20 . The non-transitory storage medium of claim 18 , wherein the program instructions, when executed by the processor, cause the user equipment to perform:
sending, to the network node, an indication for at least each TCI of at least one or more of: a signal strength of the desired signal, the IGLI, or the SILGI.
21 . The non-transitory storage medium of claim 20 , wherein at least the indication of one of more of: the strength of the desired signal, the ILGI, or the SILGI for each TCI is included in at least one of: uplink control information, an L1 reporting message, or a medium access control, MAC, message.