EP-4740320-A1 - METHODS FOR NEAR-FIELD DETECTION AND BEAM OPTIMIZATION INCLUDING RECONFIGURABLE INTELLIGENT SURFACES

EP4740320A1EP 4740320 A1EP4740320 A1EP 4740320A1EP-4740320-A1

Abstract

A method of beam correlation measurements may be implemented by a wireless transmit/receive unit (WTRU). The WTRU may be configured to receive a beam correlation measurements configuration information message that may comprise resource sets for beam correlation measurements. Each resource set may comprise reference signals that correspond to a beam. The WTRU may be configured to receive a beam correlation reporting configuration information message. The WTRU may be configured to determine to start beam correlation measurements based on an event. The WTRU may be configured to perform beam correlation measurements on the reference signals based on the received beam correlation measurements configuration information message. The reference signals may be grouped in the resources sets for beam correlation measurements. The WTRU may be configured to send a beam correlation measurements report based on a triggering condition. The WTRU may be configured to stop the beam correlation measurements.

Inventors

LORCA HERNANDO, Javier
SHOJAEIFARD, Arman
SVEDMAN, PATRICK
HAGHIGHAT, AFSHIN

Assignees

InterDigital Patent Holdings, Inc.

Dates

Publication Date: 20260513
Application Date: 20240705

Claims (20)

1. A method of beam correlation measurements, implemented by a wireless transmit/receive unit (WTRU), the method comprising: receiving a beam correlation measurements configuration information message, wherein the beam correlation measurements configuration information message comprises resource sets for beam correlation measurements, wherein each resource set comprises reference signals that correspond to a beam; receiving a beam correlation reporting configuration information message; determining to start beam correlation measurements based on an event; performing beam correlation measurements on the reference signals based on the received beam correlation measurements configuration information message, wherein the reference signals are grouped in the resources sets for beam correlation measurements; and sending a beam correlation measurements report based on a triggering condition.
2. The method of claim 1 , further comprising: stopping the beam correlation measurements, wherein the beam correlation measurements are stopped on a condition that at least one of the following is satisfied: a reference signal for beam correlation measurements is no longer detected; the WTRU was requested by a network entity to start beam correlation measurements and reports are of aperiodic type or of semi-persistent type and are de-activated; the WTRU receives a request to stop the beam correlation measurements; or beam correlation measurement triggering conditions are no longer satisfied.
3. The method of claim 1 , wherein the beam correlation measurements configuration information message further comprises: a number of repetitions N to average measurements with a configured gap between repetitions and one or more threshold values for triggering beam correlation measurements.
4. The method of claim 1 , wherein the beam correlation measurements configuration information message and the beam correlation reporting configuration information message are a same message.
5. The method of claim 1 , wherein the event to start beam correlation measurements comprises: detection of a transmission pattern of the reference signals; a received network request; or a triggering condition for beam correlation measurements.
6. The method of claim 5, wherein the triggering condition for beam correlation measurements comprises: a reference signal received power (RSRP) below an RSRP minimum threshold value, a physical downlink control channel (PDCCH) hypothetical block error rate (BLER) above a BLER maximum threshold value, a detection of a change in a state of a gNB transmitted beam, a detection of a change in physical displacement greater than a threshold value, detection of a change in signal strength greater than a threshold value, or detection of a value of a beam correlation metric larger than a threshold value.
7. The method of claim 1 , further comprising: sending a request for a network entity to transmit the reference signals; and receiving a confirmation information to measure the reference signals.
8. The method of claim 1 , wherein the beam correlation measurements report comprises: a beam correlation width lx given by a beam index difference for a X% correlation relative to a maximum; K compressed or uncompressed correlation values for all possible beam index differences; a quantized version of measured correlation metrics; an indication corresponding to a pre-defined state of a gNB transmitted beam; a signal to noise ratio (SNR); a rank; a reference signal received power (RSRP) value; or an index representing a WTRU receiver spatial beam used for the measurements.
9. The method of claim 1, wherein the beam correlation measurements comprise a sum of products of two channel transfer functions of the reference signals, wherein one of the channel transfer functions in each of the products of two channel transfer functions is first conjugated by reversing a sign of its imaginary component prior to performing beam correlation measurements.
10. The method of claim 1 , further comprising: detecting the reference signals; and obtaining channel transfer functions.
11. A wireless transmit/receive unit (WTRU), configured for beam correlation measurements the WTRU comprising: a receiver; a processor; and a transmitter, wherein: the receiver is configured to receive a beam correlation measurements configuration information message, wherein the beam correlation measurements configuration information message comprises resource sets for beam correlation measurements, wherein each resource set comprises reference signals that correspond to a beam; the receiver is further configured to receive a beam correlation reporting configuration information message; the processor is configured to determine to start beam correlation measurements based on an event; the processor is further configured to perform beam correlation measurements on the reference signals based on the received beam correlation measurements configuration information message, wherein the reference signals are grouped in the resources sets for beam correlation measurements; and the transmitter is configured to send a beam correlation measurements report based on a triggering condition.
12. The WTRU of claim 11 , wherein, the processor is further configured to stop the beam correlation measurements, wherein the beam correlation measurements are stopped on a condition that at least one of the following is satisfied: a reference signal for beam correlation measurements is no longer detected; the WTRU was requested by a network entity to start beam correlation measurements and reports are of aperiodic type or of semi-persistent type and are de-activated; the WTRU receives a request to stop the beam correlation measurements; or beam correlation measurement triggering conditions are no longer satisfied.
13. The WTRU of claim 11, wherein the beam correlation measurements configuration information message further comprises: a number of repetitions N to average measurements with a configured gap between repetitions and one or more threshold values for triggering beam correlation measurements.
14. The WTRU of claim 11, wherein the beam correlation measurements configuration information message and the beam correlation reporting configuration information message are a same message.
15. The WTRU of claim 11 , wherein the event to start beam correlation measurements comprises: detection of a transmission pattern of the reference signals; a received network request; or a triggering condition for beam correlation measurements.
16. The WTRU of claim 15, wherein the triggering condition for beam correlation measurements comprises: a reference signal received power (RSRP) below an RSRP minimum threshold value, a physical downlink control channel (PDCCH) hypothetical block error rate (BLER) above a BLER maximum threshold value, a detection of a change in a state of a gNB transmitted beam, a detection of a change in physical displacement greater than a threshold value, detection of a change in signal strength greater than a threshold value, or detection of a value of a beam correlation metric larger than a threshold value.
17. The WTRU of claim 11 , wherein: the transmitter is further configured to send a request for a network entity to transmit the reference signals; and the receiver is further configured to receive a confirmation information to measure the reference signals.
18. The WTRU of claim 11 , wherein the beam correlation measurements report comprises: a beam correlation width lx given by a beam index difference for a X% correlation relative to a maximum; K compressed or uncompressed correlation values for all possible beam index differences; a quantized version of measured correlation metrics; an indication corresponding to a pre-defined state of a gNB transmitted beam; a signal to noise ratio (SNR); a rank; a reference signal received power (RSRP) value; or an index representing a WTRU receiver spatial beam used for the measurements.
19. The WTRU of claim 11 , wherein the beam correlation measurements comprise a sum of products of two channel transfer functions of the reference signals, wherein one of the channel transfer functions in each of the products of two channel transfer functions is first conjugated by reversing a sign of its imaginary component prior to performing beam correlation measurements.
20. The WTRU of claim 11 , wherein: the processor is further configured to detect the reference signals and obtain channel transfer functions.

Description

METHODS FOR NEAR-FIELD DETECTION AND BEAM OPTIMIZATION INCLUDING RECONFIGURABLE INTELLIGENT SURFACES CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application No. 63/512,321, filed July 7, 2023, the contents of which are incorporated herein by reference. BACKGROUND [0002] The use of Reconfigurable Intelligent Surfaces (RISs) to boost signal coverage and performance has gained interest in response to their ability to tailor the radio frequency (RF) characteristics of reflected signals. A RIS is a device that comprises multiple unit cells that can manipulate (e.g. reflect, refract, and/or absorb) electromagnetic waves impinging on it. They may be envisioned to be used in wireless systems to partially control the properties of radio environments. Since RISs typically comprise large number of antenna elements, they can be used to form very narrow beams thus leading to reinforced coverage. RISs may be passive (e.g. with unit cells applying only pure phase shifts), active (e.g. involving additional amplification at the unit cells), hybrid active-passive (e.g. having a few active elements with the ability to reflect and amplify incident signals), or active (e.g. with all unit cells having active elements). SUMMARY [0003] A method of beam correlation measurements may be implemented by a wireless transmit/receive unit (WTRU). The WTRU may be configured to receive a beam correlation measurements configuration information message. The beam correlation measurements configuration information message may comprise resource sets for beam correlation measurements. Each resource set may comprise reference signals that correspond to a beam. The WTRU may be configured to receive a beam correlation reporting configuration information message. The WTRU may be configured to determine to start beam correlation measurements based on an event. The WTRU may be configured to perform beam correlation measurements on the reference signals based on the received beam correlation measurements configuration information message. The reference signals may be grouped in the resources sets for beam correlation measurements. The WTRU may be configured to send a beam correlation measurements report based on a triggering condition. The WTRU may be configured to stop the beam correlation measurements. The beam correlation measurements may be stopped on a condition that at least one of the following is satisfied: a reference signal for beam correlation measurements is no longer detected; the WTRU was requested by a network entity to start beam correlation measurements and reports are of aperiodic type or of semi-persistent type and are de-activated; the WTRU receives a request to stop the beam correlation measurements; or beam correlation measurement triggering conditions are no longer satisfied. The beam correlation measurements configuration information message may further comprise: a number of repetitions N to average measurements with a configured gap between repetitions and one or more threshold values for triggering beam correlation measurements. The beam correlation measurements configuration information message and the beam correlation reporting configuration information message may be a same message. The event to start beam correlation measurements may comprise: detection of a transmission pattern of the reference signals; a received network request; or a triggering condition for beam correlation measurements. The triggering condition for beam correlation measurements may comprise: a reference signal received power (RSRP) below an RSRP minimum threshold value, a physical downlink control channel (PDCCH) hypothetical block error rate (BLER) above a BLER maximum threshold value, a detection of a change in a state of a gNB transmitted beam, a detection of a change in physical displacement greater than a threshold value, detection of a change in signal strength greater than a threshold value, or detection of a value of a beam correlation metric larger than a threshold value. The WTRU may be configured to send a request for a network entity to transmit the reference signals and receive a confirmation information to measure the reference signals. The beam correlation measurements report may comprise: a beam correlation width lx given by a beam index difference for a X% correlation relative to a maximum; K compressed or uncompressed correlation values for all possible beam index differences; a quantized version of measured correlation metrics; an indication corresponding to a pre-defined state of a gNB transmitted beam; a signal to noise ratio (SNR); a rank; a reference signal received power (RSRP) value; or an index representing a WTRU receiver spatial beam used for the measurements. The beam correlation measurements may comprise a sum of products of two channel transfer functions of the reference signals, wherein one of the channel transfer functions in each of the products of two channe