Two-stage bistatic sensing

Abstract

Systems, methods, and instrumentalities are described herein for performing two-stage bistatic sensing, for example, using multiple beams in a mobile network. A device (e.g., a WTRU) may comprise a processor configured to perform one or more actions. The device may perform first sensing associated with a first set of beams, determine a scatterer based on the first sensing determine that at least a first beam, from the first set of beams, is associated with the scatterer and a first characteristic associated with at least the first beam, send a first report, wherein the first report indicates the scatterer, at least the first beam associated with the scatterer, and the first characteristic associated with at least the first beam, perform second sensing associated with a second set of beams, determine a second beam, from the second set of beams, and a second characteristic associated with the second beam, determine that a cross-correlation associated with the first characteristic and the second characteristic satisfies a threshold, and send a second report, wherein the second report includes an indication that the scatterer is verified, and an indication of the second beam.

Description

TWO-STAGE BISTATIC SENSINGCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 537,242, filed September 8, 2023 the contents of which is incorporated by reference herein.BACKGROUND

[0002] Mobile communications using wireless communication continue to evolve. A fifth generation may be referred to as 5G. A previous (legacy) generation of mobile communication may be, for example, fourth generation (4G) long term evolution (LTE).SUMMARY

[0003] Systems, methods, and instrumentalities are described herein that may be associated with performing two-stage bistatic sensing, for example, using multiple beams in a mobile network.

[0004] A device (e.g., a WTRU) may comprise a processor configured to perform one or more actions. The device may perform first sensing associated with a first set of beams (e.g., a first stage of sensing). The device may determine a scatterer based on the first sensing. The device may determine that at least a first beam, from the first set of beams, is associated with the scatterer. The device may determine a first characteristic associated with at least the first beam. The device may send a first report. The first report may indicate the scatterer, at least the first beam associated with the scatterer, and the first characteristic associated with at least the first beam.

[0005] The device may perform second sensing associated with a second set of beams. The device may determine a second beam, from the second set of beams. The device may determine a second characteristic associated with the second beam. The device may determine that a cross-correlation associated with the first characteristic and the second characteristic is above a threshold (e.g., the device may determine that the scatterer is verified based on the cross-correlation associated with the first characteristic and the second characteristic satisfies the threshold). The device may send a second report. The second report may include an indication that the scatterer is verified. The second report may include an indication of the second beam.

[0006] The second report may further indicate the second characteristic associated with the second beam. The first set of beams may include a first number of beams. The second set of beams may include a second number of beams. The second number of beams may be less than the first number of beams. At least the first beam may be within the second set of beams. The first characteristic associated with at least the first beam may be at least one of: a first channel impulse response (Cl R); a first channel frequency response (CFR); or a first power delay profile (PDP). The second characteristic associated with the second beam may be at least one of: a second CIR; a second CFR; or a second PDP.

[0007] The device may be further configured to perform a bistatic sensing measurement associated with the second beam. The bistatic sensing measurement associated with the second beam may include at least one of: a delay; an angle of arrival; or a received power. The second report may include the bistatic sensing measurement.

[0008] The bistatic sensing measurement may include (e.g., indicate) relative differences between measurements obtained using the first set of beams and the second set of beams. The threshold may be a first threshold. The determination that at least the first beam of the first set of beams is associated with the scatterer may further include the device being configured to: determine that the scatterer is associated with a second beam from the first set of beams. The device may be further configured to perform a crosscorrelation associated with the first beam of the first set of beams and the second beam of the first set of beams. The device may be further configured to determine that the cross-correlation associated with the first beam of the first set of beams and the second beam of the first set of beams satisfies a second threshold.

[0009] The second set of beams may be selected from the first set of beams based on an association between the scatterer and the first set of beams. The first beam may be associated with a first power. The second beam may be associated with a second power.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1 A is a system diagram illustrating an example communications system in which one or more disclosed embodiments may be implemented.

[0011] FIG. 1 B is a system diagram illustrating an example wireless transmit / receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1A according to an embodiment.

[0012] FIG. 1 C is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communications system illustrated in FIG. 1 A according to an embodiment.

[0013] FIG. 1 D is a system diagram illustrating a further example RAN and a further example CN that may be used within the communications system illustrated in FIG. 1A according to an embodiment.

[0014] FIG. 2A depicts an example of monostatic sensing.

[0015] FIG. 2B depicts an example of bistatic sensing.

[0016] FIG. 2C. depicts an example of multi-static sensing.

[0017] FIG. 3 depicts an example of simultaneous transmission of three beams.

[0018] FIG. 4 depicts an example of multiple beams being transmitted over non-overlapping frequency resources.

[0019] FIG. 5 depicts an example of multiple beams transmitted in a frequency-staggered manner.

[0020] FIG. 6 depicts an example of MPCs identified as a set of scatterers.

[0021] FIG. 7 depicts an example of first stage course sensing with a first set of beams.

[0022] FIG. 8 depicts an example of WTRU operations in a first stage (e.g., course sensing) of a two- stage sensing method.

[0023] FIG. 9 depicts an example of second stage (e.g., fine) sensing using a reduced number of beams.

[0024] FIG. 10 depicts an example of WTRU operations in a second stage (e.g., fine sensing) of a two- stage sensing method.

[0025] FIG. 11 depicts an example message passing in a two-stage sensing method.

[0026] FIG. 12 depicts an example of gNB configuring a WTRU to perform sensing.

[0027] FIG. 13 depicts an example of a WTRU requesting sensing of a specific scatterer or beam.DETAILED DESCRIPTION

[0028] FIG. 1 A is a diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. The communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tail unique-word DFT-Spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block-filtered OFDM, filter bank multicarrier (FBMC), and the like.

[0029] As shown in FIG. 1 A, the communications system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a RAN 104 / 113, a CN 106 / 115, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, though it will be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d, any of which may be referred to as a “station” and / or a “STA”, may be configured to transmit and / or receive wireless signals and may include a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. Any of the WTRUs 102a, 102b, 102c and 102d may be interchangeably referred to as a UE.

[0030] The communications systems 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106 / 115, the I nternet 110, and / or the other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node-B, an eNode B, a Home Node B, a Home eNode B, a gNB, a NR NodeB, a site controller, an access point (AP), a wireless router, and the like. While the base stations 114a, 114b are each depicted as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0031] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, etc. The base station 114a and / or the base station 114b may be configured to transmit and / or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage for a wireless service to a specific geographical area that may be relatively fixed or that may change over time. The cell may further be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e., one foreach sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and / or receive signals in desired spatial directions.

[0032] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0033] More specifically, as noted above, the communications system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, the base station 114a in the RAN 104 / 113 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 115 / 116 / 117 using wideband CDMA (WCDMA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink (DL) Packet Access (HSDPA) and / or High-Speed UL Packet Access (HSUPA).

[0034] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and / or LTE-Advanced Pro (LTE-A Pro).

[0035] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR Radio Access , which may establish the air interface 116 using New Radio (NR).

[0036] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may implement LTE radio access and NR radio access together, for instance using dual connectivity (DC) principles. Thus, the air interface utilized by WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions sent to / from multiple types of base stations (e.g., a eNB and a gNB).

[0037] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System forMobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the like.

[0038] The base station 114b in FIG. 1 A may be a wireless router, Home Node B, Home eNode B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a roadway, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR etc.) to establish a picocell or femtocell. As shown in FIG. 1 A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not be required to access the Internet 110 via the CN 106 / 115.

[0039] The RAN 104 / 113 may be in communication with the CN 106 / 115, which may be any type of network configured to provide voice, data, applications, and / or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have varying quality of service (QoS) requirements, such as differing throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. The CN 106 / 115 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. Although not shown in FIG. 1A, it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may be utilizing a NR radio technology, the CN 106 / 115 may also be in communication with another RAN (not shown) employing a GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0040] The CN 106 / 115 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or the other networks 112. The PSTN 108 may include circuit- switched telephone networks that provide plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the transmission control protocol (TCP), user datagram protocol (UDP) and / or the internet protocol (IP) in the TCP / IP internet protocol suite. The networks 112 may include wired and / or wireless communications networks owned and / or operated by other service providers. For example,the networks 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 / 113 or a different RAT.

[0041] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in FIG. 1A may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0042] FIG. 1 B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1 B, the WTRU 102 may include a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and / or other peripherals 138, among others. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0043] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits, any other type of integrated circuit (IC), a state machine, and the like. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. While FIG. 1 B depicts the processor 118 and the transceiver 120 as separate components, it will be appreciated that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0044] The transmit / receive element 122 may be configured to transmit signals to, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in one embodiment, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In an embodiment, the transmit / receive element 122 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. It will be appreciated that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0045] Although the transmit / receive element 122 is depicted in FIG. 1 B as a single element, the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0046] The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit / receive element 122 and to demodulate the signals that are received by the transmit / receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11 , for example.

[0047] The processor 118 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or organic light-emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from, and store data in, any type of suitable memory, such as the non-removable memory 130 and / or the removable memory 132. The non-removable memory 130 may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0048] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control the power to the other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and the like.

[0049] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or in lieu of, the information from the GPS chipset 136, the WTRU 102 may receive location information over the air interface 116 from a base station (e.g., base stations 114a, 114b) and / or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable locationdetermination method while remaining consistent with an embodiment.

[0050] The processor 118 may further be coupled to other peripherals 138, which may include one or more software and / or hardware modules that provide additional features, functionality and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photographs and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a Virtual Reality and / or Augmented Reality (VR / AR) device, an activity tracker, and the like. The peripherals 138 may include one or more sensors, the sensors may be one or more of a gyroscope, an accelerometer, a hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geolocation sensor; an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0051] The WTRU 102 may include a full duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for both the UL (e.g., for transmission) and downlink (e.g., for reception) may be concurrent and / or simultaneous. The full duplex radio may include an interference management unit to reduce and or substantially eliminate self-interference via either hardware (e.g., a choke) or signal processing via a processor (e.g., a separate processor (not shown) or via processor 118). In an embodiment, the WRTU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for either the UL (e.g., for transmission) or the downlink (e.g., for reception)).

[0052] FIG. 1 C is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0053] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and / or receive wireless signals from, the WTRU 102a.

[0054] Each of the eNode-Bs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, and the like. As shown in FIG. 1 C, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0055] The CN 106 shown in FIG. 1 C may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. While each of the foregoing elements are depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0056] The MME 162 may be connected to each of the eNode-Bs 162a, 162b, 162c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and / or WCDMA.

[0057] The SGW 164 may be connected to each of the eNode Bs 160a, 160b, 160c in the RAN 104 via the S1 interface. The SGW 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring user planes during inter- eNode B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing contexts of the WTRUs 102a, 102b, 102c, and the like.

[0058] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0059] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112, which may include other wired and / or wireless networks that are owned and / or operated by other service providers.

[0060] Although the WTRU is described in FIGS. 1 A-1 D as a wireless terminal, it is contemplated that in certain representative embodiments that such a terminal may use (e.g., temporarily or permanently) wired communication interfaces with the communication network.

[0061] In representative embodiments, the other network 112 may be a WLAN.

[0062] A WLAN in Infrastructure Basic Service Set (BSS) mode may have an Access Point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have an access or an interface to a Distribution System (DS) or another type of wired / wireless network that carries traffic in to and / or out ofthe BSS. Traffic to STAs that originates from outside the BSS may arrive through the AP and may be delivered to the STAs. Traffic originating from STAs to destinations outside the BSS may be sent to the AP to be delivered to respective destinations. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP and the AP may deliver the traffic to the destination STA. The traffic between STAs within a BSS may be considered and / or referred to as peer-to- peer traffic. The peer-to-peer traffic may be sent between (e.g., directly between) the source and destination STAs with a direct link setup (DLS). In certain representative embodiments, the DLS may use an 802.11e DLS or an 802.11 z tunneled DLS (TDLS). A WLAN using an Independent BSS (I BSS) mode may not have an AP, and the STAs (e.g., all of the STAs) within or using the IBSS may communicate directly with each other. The IBSS mode of communication may sometimes be referred to herein as an “ad- hoc” mode of communication.

[0063] When using the 802.11ac infrastructure mode of operation or a similar mode of operations, the AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20 MHz wide bandwidth) or a dynamically set width via signaling. The primary channel may be the operating channel of the BSS and may be used by the STAs to establish a connection with the AP. In certain representative embodiments, Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) may be implemented, for example, in in 802.11 systems. For CSMA / CA, the STAs (e.g., every STA), including the AP, may sense the primary channel. If the primary channel is sensed / detected and / or determined to be busy by a particular STA, the particular STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0064] High Throughput (HT) STAs may use a 40 MHz wide channel for communication, for example, via a combination of the primary 20 MHz channel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHz wide channel.

[0065] Very High Throughput (VHT) STAs may support 20MHz, 40 MHz, 80 MHz, and / or 160 MHz wide channels. The 40 MHz, and / or 80 MHz, channels may be formed by combining contiguous 20 MHz channels. A 160 MHz channel may be formed by combining 8 contiguous 20 MHz channels, or by combining two non-contiguous 80 MHz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, the data, after channel encoding, may be passed through a segment parser that may divide the data into two streams. Inverse Fast Fourier Transform (IFFT) processing, and time domain processing, may be done on each stream separately. The streams may be mapped on to the two 80 MHz channels, and the data may be transmitted by a transmitting STA. At the receiver of the receiving STA, the above described operation for the 80+80 configuration may be reversed, and the combined data may be sent to the Medium Access Control (MAC).

[0066] Sub 1 GHz modes of operation are supported by 802.11 af and 802.11 ah. The channel operating bandwidths, and carriers, are reduced in 802.11 af and 802.11 ah relative to those used in 802.11 n, and 802.11ac. 802.11 af supports 5 MHz, 10 MHz and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11 ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non- TVWS spectrum. According to a representative embodiment, 802.11 ah may support Meter Type Control / Machine-Type Communications, such as MTC devices in a macro coverage area. MTC devices may have certain capabilities, for example, limited capabilities including support for (e.g., only support for) certain and / or limited bandwidths. The MTC devices may include a battery with a battery life above a threshold (e.g., to maintain a very long battery life).

[0067] WLAN systems, which may support multiple channels, and channel bandwidths, such as 802.11 n, 802.11 ac, 802.11 af, and 802.11 ah, include a channel which may be designated as the primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by a STA, from among all STAs in operating in a BSS, which supports the smallest bandwidth operating mode. In the example of 802.11 ah, the primary channel may be 1 MHz wide for STAs (e.g., MTC type devices) that support (e.g., only support) a 1 MHz mode, even if the AP, and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or Network Allocation Vector (NAV) settings may depend on the status of the primary channel. If the primary channel is busy, for example, due to a STA (which supports only a 1 MHz operating mode), transmitting to the AP, the entire available frequency bands may be considered busy even though a majority of the frequency bands remains idle and may be available.

[0068] In the United States, the available frequency bands, which may be used by 802.11 ah, are from 902 MHz to 928 MHz. In Korea, the available frequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11 ah is 6 MHz to 26 MHz depending on the country code.

[0069] FIG. 1 D is a system diagram illustrating the RAN 113 and the CN 115 according to an embodiment. As noted above, the RAN 113 may employ an NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also be in communication with the CN 115.

[0070] The RAN 1 13 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 113 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMOtechnology. For example, gNBs 180a, 108b may utilize beamforming to transmit signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a, for example, may use multiple antennas to transmit wireless signals to, and / or receive wireless signals from, the WTRU 102a. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on unlicensed spectrum while the remaining component carriers may be on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement Coordinated Multi-Point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and / or gNB 180c).

[0071] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using transmissions associated with a scalable numerology. For example, the OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using subframe or transmission time intervals (TTIs) of various or scalable lengths (e.g., containing varying number of OFDM symbols and / or lasting varying lengths of absolute time).

[0072] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c without also accessing other RANs (e.g., such as eNode-Bs 160a, 160b, 160c). In the standalone configuration, WTRUs 102a, 102b, 102c may utilize one or more of gNBs 180a, 180b, 180c as a mobility anchor point. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration WTRUs 102a, 102b, 102c may communicate with / connect to gNBs 180a, 180b, 180c while also communicating with / connecting to another RAN such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In the non-standalone configuration, eNode-Bs 160a, 160b, 160c may serve as a mobility anchor for WTRUs 102a, 102b, 102c and gNBs 180a, 180b, 180c may provide additional coverage and / or throughput for servicing WTRUs 102a, 102b, 102c.

[0073] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, support of network slicing, dual connectivity, interworking between NR and E- UTRA, routing of user plane data towards User Plane Function (UPF) 184a, 184b, routing of control planeinformation towards Access and Mobility Management Function (AMF) 182a, 182b and the like. As shown in FIG. 1 D, the gNBs 180a, 180b, 180c may communicate with one another over an Xn interface.

[0074] The CN 115 shown in FIG. 1 D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. While each of the foregoing elements are depicted as part of the CN 115, it will be appreciated that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0075] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may serve as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, support for network slicing (e.g., handling of different PDU sessions with different requirements), selecting a particular SMF 183a, 183b, management of the registration area, termination of NAS signaling, mobility management, and the like. Network slicing may be used by the AMF 182a, 182b in order to customize CN support for WTRUs 102a, 102b, 102c based on the types of services being utilized WTRUs 102a, 102b, 102c. For example, different network slices may be established for different use cases such as services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services for machine type communication (MTC) access, and / or the like. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies such as WiFi.

[0076] The SMF 183a, 183b may be connected to an AMF 182a, 182b in the CN 115 via an N11 interface. The SMF 183a, 183b may also be connected to a UPF 184a, 184b in the CN 115 via an N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b and configure the routing of traffic through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating UE IP address, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notifications, and the like. A PDU session type may be IP-based, non-IP based, Ethernetbased, and the like.

[0077] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet- switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, and the like.

[0078] The CN 115 may facilitate communications with other networks. For example, the CN 115 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112, which may include other wired and / or wireless networks that are owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to a local Data Network (DN) 185a, 185b through the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0079] In view of Figures 1 A-1 D, and the corresponding description of Figures 1 A-1 D, one or more, or all, of the functions described herein with regard to one or more of: WTRU 102a-d, Base Station 114a-b, eNode-B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-b, UPF 184a-b, SMF 183a-b, DN 185a-b, and / or any other device(s) described herein, may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more, or all, of the functions described herein. For example, the emulation devices may be used to test other devices and / or to simulate network and / or WTRU functions.

[0080] The emulation devices may be designed to implement one or more tests of other devices in a lab environment and / or in an operator network environment. For example, the one or more emulation devices may perform the one or more, or all, functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network in order to test other devices within the communication network. The one or more emulation devices may perform the one or more, or all, functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The emulation device may be directly coupled to another device for purposes of testing and / or may performing testing using over-the-air wireless communications.

[0081] The one or more emulation devices may perform the one or more, including all, functions while not being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation devices may be utilized in a testing scenario in a testing laboratory and / or a non-deployed (e.g., testing) wired and / or wireless communication network in order to implement testing of one or more components. The one or more emulation devices may be test equipment. Direct RF coupling and / or wireless communications via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0082] Systems, methods, and instrumentalities are described herein that may be associated with performing two-stage bistatic sensing, for example, using multiple beams in a mobile network.

[0083] A device (e.g., a WTRU) may comprise a processor configured to perform one or more actions. The device may perform first sensing associated with a first set of beams (e.g., a first stage of sensing). The device may determine a scatterer based on the first sensing. The device may determine that at least a first beam, from the first set of beams, is associated with the scatterer. The device may determine a first characteristic associated with at least the first beam. The device may send a first report. The first report may indicate the scatterer, at least the first beam associated with the scatterer, and the first characteristic associated with at least the first beam.

[0084] The device may perform second sensing associated with a second set of beams. The device may determine a second beam, from the second set of beams. The device may determine a second characteristic associated with the second beam. The device may determine that a cross-correlation associated with the first characteristic and the second characteristic is above a threshold (e.g., the device may determine that the scatterer is verified based on the cross-correlation associated with the first characteristic and the second characteristic satisfies the threshold). The device may send a second report. The second report may include an indication that the scatterer is verified. The second report may include an indication of the second beam.

[0085] The second report may further indicate the second characteristic associated with the second beam. The first set of beams may include a first number of beams. The second set of beams may include a second number of beams. The second number of beams may be less than the first number of beams. At least the first beam may be within the second set of beams. The first characteristic associated with at least the first beam may be at least one of: a first channel impulse response (CIR); a first channel frequency response (CFR); or a first power delay profile (PDP). The second characteristic associated with the second beam may be at least one of: a second CIR; a second CFR; or a second PDP.

[0086] The device may be further configured to perform a bistatic sensing measurement associated with the second beam. The bistatic sensing measurement associated with the second beam may include at least one of: a delay; an angle of arrival; or a received power. The second report may include the bistatic sensing measurement.

[0087] The bistatic sensing measurement may include (e.g., indicate) relative differences between measurements obtained using the first set of beams and the second set of beams. The threshold may be a first threshold. The determination that at least the first beam of the first set of beams is associated with the scatterer may further include the device being configured to: determine that the scatterer is associated with a second beam from the first set of beams. The device may be further configured to perform a crosscorrelation associated with the first beam of the first set of beams and the second beam of the first set of beams. The device may be further configured to determine that the cross-correlation associated with thefirst beam of the first set of beams and the second beam of the first set of beams satisfies a second threshold.

[0088] The second set of beams may be selected from the first set of beams based on an association between the scatterer and the first set of beams. The first beam may be associated with a first power. The second beam may be associated with a second power.

[0089] A device (e.g., a WTRU) may comprise a processor configured to perform one or more actions. The device may perform first sensing associated with a first set of beams (e.g., a first stage of sensing). The device may determine a first scatterer set that includes a first scatterer. The device may determine one or more beams associated with the first scatterer and a characteristic associated with the first scatterer.The device may send a first report that indicates the first scatterer, the one or more beams associated with the first scatterer, and / or the characteristic associated with the first scatterer.

[0090] The device may perform second sensing associated with a second set of beams (e.g., a second stage of sensing). The device may verify the first scatterer based on a cross-correlation associated with the first sensing and the second sensing. The device may perform bistatic detection associated with the first scatterer. The device may send a second report that indicates the first scatterer is verified.

[0091] The determination of the first scatterer set may be based on a channel response associated with the performed first sensing.

[0092] The first set of beams may comprise a first number of beams and the second set of beam may comprise a second number of beams. The second number of beams may less than the first number of beams (e.g., fine sensing may be performed after coarse sensing).

[0093] The second report may indicate a sensing measurement associated with the performed bistatic detection.

[0094] A device (e.g., a WTRU) may comprise a processor configured to perform one or more actions. The device may obtain a first set of channel responses associated with a first set of beams. The first set of channel responses may include a channel response associated with each beam in the first set of beams. The device may identify a first set of scatterers (e.g., where the first set of scatterers includes a beamspecific scatterer of each beam in the first set of beams based on the channel response for the respective beam) and may determine, for each scatterer in the first set of scatterers, an association to one or more beams of the first set of beams. The device may send a first report that includes the first set of scatterers and the respective association for each scatterer in the first set of scatterers.

[0095] The device may obtain a second set of channel responses associated with a second set of beam. The second set of channel responses may include a channel response associated with each beam in the second set of beams. The device may identify a second set of scatterers (e.g., where the second set ofscatterers includes a beam-specific scatterer of each beam in the second set of beams based on the channel response for the respective beam). The device may determine, for each beam in the second set of beams, a comparison metric to each beam in the first set of beams. The comparison metric may be based on the channel response associated with the respective beam in the first set of beams and the channel response associated with the respective beam in the second set of beams. The device may send a first indication indicating at least one beam from the second set of beams and one or more beams from the first set of beams for which the comparison metric is above a threshold. The device may send a second indication indicating at least one beam from the second set of beams for which the comparison metric is below the threshold for all beams from the first set of beams.

[0096] The device may perform non-coherent measurements for each scatterer in the first set of scatterers. The determination of the association of each scatterer in the first set of scatterers to one or more beams of the first set of beams may be based on the non-coherent measurements.

[0097] The device may perform bistatic sensing on the second set of beams.

[0098] The channel response associated with each beam in the first set of beams and the channel response associated with each beam in the second set of beams may (e.g., each) be one or more of: a channel impulse response (CIR), a channel frequency response (CFR), or a power delay profile (PDP).

[0099] Systems, methods, and instrumentalities are described herein for performing two-stage bistatic sensing, for example, using multiple beams in a mobile network.

[0100] A device (e.g., a WTRU) may comprise a processor configured to perform one or more actions. The device may perform first sensing associated with a first set of beams (e.g., a first stage of sensing). The device may determine a first scatterer set that includes a first scatterer. The device may determine one or more beams associated with the first scatterer and a characteristic associated with the first scatterer.The device may send a first report that indicates the first scatterer, the one or more beams associated with the first scatterer, and / or the characteristic associated with the first scatterer.

[0101] The device may perform second sensing associated with a second set of beams (e.g., a second stage of sensing). The device may verify the first scatterer based on a cross-correlation associated with the first sensing and the second sensing. The device may perform bistatic detection associated with the first scatterer. The device may send a second report that indicates the first scatterer is verified.

[0102] The determination of the first scatterer set may be based on a channel response associated with the performed first sensing.

[0103] The first set of beams may comprise a first number of beams and the second set of beam may comprise a second number of beams. The second number of beams may less than the first number of beams (e.g., fine sensing may be performed after coarse sensing).

[0104] The second report may indicate a sensing measurement associated with the performed bistatic detection.

[0105] A device (e.g., a WTRU) may comprise a processor configured to perform one or more actions. The device may obtain / determine a first set of channel responses associated with a first set of beams. The first set of channel responses may include a channel response associated with each beam in the first set of beams. The device may identify a first set of scatterers (e.g., where the first set of scatterers includes a beam-specific scatterer of each beam in the first set of beams based on the channel response for the respective beam) and may determine, for each scatterer in the first set of scatterers, an association to one or more beams of the first set of beams. The device may send a first report that includes the first set of scatterers and the respective association for each scatterer in the first set of scatterers.

[0106] The device may obtain / determine a second set of channel responses associated with a second set of beam. The second set of channel responses may include a channel response associated with each beam in the second set of beams. The device may identify a second set of scatterers (e.g., where the second set of scatterers includes a beam-specific scatterer of each beam in the second set of beams based on the channel response for the respective beam). The device may determine, for each beam in the second set of beams, a comparison metric to each beam in the first set of beams. The comparison metric may be based on the channel response associated with the respective beam in the first set of beams and the channel response associated with the respective beam in the second set of beams. The device may send a first indication indicating at least one beam from the second set of beams and one or more beams from the first set of beams for which the comparison metric is above a threshold. The device may send a second indication indicating at least one beam from the second set of beams for which the comparison metric is below the threshold for all beams from the first set of beams.

[0107] The device may perform non-coherent measurements for each scatterer in the first set of scatterers. The determination of the association of each scatterer in the first set of scatterers to one or more beams of the first set of beams may be based on the non-coherent measurements.

[0108] The device may perform bistatic sensing on the second set of beams.

[0109] The channel response associated with each beam in the first set of beams and the channel response associated with each beam in the second set of beams may (e.g., each) be one or more of: a channel impulse response (CIR), a channel frequency response (CFR), or a power delay profile (PDP).

[0110] Two-stage bistatic sensing (e.g., using multiple beams in a mobile network) may be performed. Sensing may be defined as the detection and / or estimation of characteristics of objects within a mobile network environment. Sensing may include estimating spatial and / or temporal characteristics (e.g., relativeposition, angular location, speed, orientation, size, etc.). Sensing may be employed in a wireless system, for example, in the context of integrated sensing and communication (ISAC).

[0111] Different types (e.g., modes) of sensing, for example, monostatic sensing, bistatic sensing, or multi-static sensing, may be provided. FIG. 2A depicts an example of monostatic sensing. FIG. 2B depicts an example of bistatic sensing. FIG. 20 depicts an example of multi-static sensing. The sensing method used (e.g., monostatic, bistatic, or multi-static) may depend on the location of the transmitter and / or the receiver. In examples, monostatic sensing may be used when the transmitter and the receiver are colocated, as shown in FIG. 2A. In examples, bistatic sensing may be used when the transmitter and the receiver exist at different sides, as shown in FIG. 2B. Bistatic sensing may be extended to multi-static sensing, for example, when multiple receivers in different locations are involved, as shown in FIG. 2C.

[0112] Monostatic sensing may refer to the sensing mode where the transmitter and receiver are colocated (e.g., where the transmitter may transmit the sensing signal and receive the echoes signal from the environment). In the context of new radio (NR), monostatic sensing may be utilized at the WTRU-side or the network-side (e.g., by a network entity such as a gNB), which may, for example, allow a single device to perform sensing of the environment. A single device performing monostatic sensing may require full duplex capabilities at the sensing device or half duplex (e.g., by dividing the transmission and receiving into separate windows).

[0113] Bistatic sensing may be utilized between the network (e.g., by a network entity such as a base station, for example, a gNB) and a WTRU. For bistatic sensing the network or the WTRU may act as the transmitting device and the other may act as the receiving device, for example, if both sides are of the same type (e.g., WTRU-WTRU, or gNB-gNB) or different type (e.g., gNB-WTRU, or WTRU-gNB). Bistatic sensing may not require full duplex transmission.

[0114] NR positioning may be performed. Networking standards may define methods for NR positioning (e.g., for the downlink (DL) and / or the uplink (UL)). Positioning Reference Signals (PRS) may be defined for NR positioning for the DL. Sounding reference signal for positioning (SRSp) may be defined for NR positioning for the UL. In the DL, the PRS may be a one-port signal with, for example, up to 12 OFDM symbols per slot in time (e.g., with a comb frequency multiplexed arrangement to allow for transmitting multiple PRSs from multiple TRPs). In the DL, multiple TRPs may transmit the PRS over shared resources (e.g., allowing the WTRU to estimate its position based on various positioning measurements (e.g., RSRP, Doppler, DL Time difference of arrival (DL-TDoA), etc.)). The SRSp signals may be one-port signals that span on, for example, up to 14 OFDM symbols (e.g., in up to full bandwidth) and may be transmitted from multiple users in a frequency multiplexed manner for multi-user transmission. In the UL, the WTRU may utilize the SRS signals for positioning (e.g., where the WTRU may transmit SRS resources towards multipleTRPs, which may then perform positioning measurements). UL and DL techniques may be combined (e.g., where the TRP transmits the PRS in the DL and the WTRU transmits the SRS).

[0115] A set of sensing use cases may be identified (e.g., which may include different types of sensing, such as monostatic and bistatic sensing). In examples, in bistatic sensing detecting the MPCs may be insufficient to differentiate between various targets. This limitation may arise because the reflections may alone lack sufficient information to distinguish between two targets (e.g., located at same distances from the WTRU). Some processing of the wideband Channel Impulse Response (CIR) or Power Delay Profile (PDP) responses may be performed (e.g., to effectively classify targets during sensing).

[0116] Sensing using a single beam may achieve sensing accuracy but introduce latency (e.g., since multiple single beams need to be activated separately (e.g., over time) to cover a wide area). Sensing using multiple beams may improve the sensing latency at the cost of a reduced sensing accuracy (e.g., since a wider area may be covered simultaneously).

[0117] The accuracy of sensing over a range, R, may be measured using the Cramer-Rao lower bound(CRLB) bound, which may be dependent on the BW and SNR as: c2CRLB-. var R) > ■=- -B2X SNR

[0118] Where c may be the speed of light and B2may be the mean square bandwidth. Using a single beam for transmitting sensing reference signal (e.g., PRS, CSI-RS, etc.) over the power and BW resources may lead to high sensing accuracy. The transmitter (e.g., TRP) may need to switch between multiple single transmission for sensing (e.g., in order to cover a wide area). Switching between multiple single transmission for sensing may introduce latency to the sensing procedure. Multiple beams (e.g., NB beams) may be multiplexed (e.g., over frequency domain or code domain) while sharing the available power and bandwidth resources to cover a wider area (e.g., to improve the latency). This may allow for increasing the coverage area but the accuracy of sensing (e.g., CRLB) may be reduced.

[0119] Feature(s) associated with two stage sensing are provided herein. A two-stage bistatic sensing method, which may be used as an example of a sensing method, may be performed. In the first (e.g., initial) stage, the WTRU (e.g., of a user) may detect scatterer(s). The scatterer(s) may be detected by analyzing the channel responses of a first set of beams. The WTRU may communicate (e.g., to a base station of the network) an association between scatterers and beams. In the second (e.g., subsequent) stage, the WTRU may conduct measurement(s) (e.g., bistatic measurements, or bistatic sensing measurements) on a second set of beams. The WTRU may leverage (e.g., use) the feedback received from the first stage when conducting and / or evaluating the measurement(s) (e.g., bistatic measurements) on the second set of beams.

[0120] A WTRU may be configured for two-stage bistatic sensing. In examples, a first stage of two-stage bistatic sensing may include the WTRU performing one or more of the following.

[0121] The WTRU may receive a configuration (e.g., of time-frequency resource(s)) about (e.g., associated with, indicating, etc.) a first set of beams for sensing (e.g., one or more of: a set of TCI states containing QCL relationships for the beams, time-frequency resource(s) allocation, measurement(s) to perform, or a threshold). The configuration may be received, for example, via RRC configuration or DCI signaling of MAC CE.

[0122] The WTRU may receive a set of reference signals for sensing on the configured time-frequency resources allocated for the first set of beams.

[0123] The WTRU may obtain (e.g., determine) channel response(s) associated with a beam (e.g., respective channel response(s) associated with each beam) of the first set of beams. The channel responses may include, for example, one or more of the channel impulse response (CIR), the channel frequency response (CFR), or the power delay profile (PDP).

[0124] The WTRU may identify / determine (e.g., label) one or more beam-specific scatterers (e.g., a respective set of Multipath Components (MPCs)) for each beam, for example, where each identified beamspecific scatterer may be labeled with a beam-specific scatterer ID. The identification may be based on the obtained channel response(s) (e.g., CIR, CFR, or PDP).

[0125] The WTRU may perform non-coherent measurement(s) on the channel response(s) of the scatterer(s) (e.g., beam-specific scatterer(s), or set of MPCs) detected in the beam(s) (e.g., each beam, or all beams). The non-coherent measurement(s) may be used by the WTRU to, for example, detect common scatterer(s) between beams (e.g., different beams), for example, using the cross-correlation between the PDPs of the beams.

[0126] The WTRU may determine one or more scatterers from the beam-specific scatterers and / or the detected common scatterers. The WTRU may label (e.g., identify) each scatterer (e.g., with a scatterer ID). The WTRU may associate each (e.g., labeled) scatterer (e.g., set of MPCs) with a single beam or set of beams (e.g., based on the non-coherent measurement(s)).

[0127] In examples, if the cross-correlation of a beam-specific scatterer detected by two or more beams is above a threshold (e.g., a specific threshold), then a scatterer may be determined as a common scatterer to be associated with those beams (e.g., the scatterer detected by each of the beams may be the same scatterer).

[0128] In examples, if a scatterer k" is determined to be the same scatterer as beam-specific scatterer k and k' for beams nband nb' (e.g., the cross-correlation between the two beam-specific scatterers may be above a specific threshold), the WTRU may associate scatterer k" with beams nband rib.

[0129] The WTRU may send (e.g., to a base station of the network, such as a gNB) a list of labelled scatterers (e.g., MPCs) and their associations with beam(s) (e.g., to a single beam or set of beams).

[0130] In examples, a second stage of two-stage bistatic sensing may include the WTRU performing one or more of the following.

[0131] The WTRU may run a process (e.g., an iterative process) to sense scatterers (e.g., each of the scatterers) detected in the first stage.

[0132] The WTRU may receive an indication of a second set of beams that may be activated (e.g., are activated) for bistatic sensing. The indication may indicate one or more of: a set of TCI states containing QCL relationships for the beams, time / -frequency resource(s) allocation, measurement(s) to perform, and or a threshold). The WTRU may receive the indication, for example, via a MAC CE.

[0133] The WTRU may receive a set of reference signals for sensing on the configured time-frequency resources allocated for the second set of beams.

[0134] The WTRU may obtain / determine the channel response(s) associated with the second set of beams. The channel response(s) may include one or more of: CIR, CFR, or PDP.

[0135] The WTRU may identify / determine (e.g., label) one or more beam-specific scatterers (e.g., a respective set of MPCs) for each beam (e.g., where each identified beam-specific scatterer may be labeled with a beam-specific scatterer ID). The WTRU may identify (e.g., label) the one or more scatterers based on the channel responses (e.g., obtained CIR, CFR, or PDP).

[0136] The WTRU may obtain / determine a metric comparing the channel responses in the first stage and the channel responses in the second stage (e.g., a comparison metric). The WTRU may use the comparison metric to verify scatterers (e.g., verify a cross-correlation between parameter(s), for example, the PDP profiles of the first set of beams from the first stage and the second set of beams in the second stage). A beam (e.g., each beam) in the second set of beams may have a comparison metric for a beam (e.g., each beam) in the first set of beams.

[0137] The WTRU may perform measurements (e.g., bistatic measurements, or bistatic sensing measurements) on the second set of beams (e.g., the delay, angle of arrival, received power, etc.) of the labelled scatterers (e.g., MPCs).

[0138] The WTRU may send an indication (e.g., a first indication) to the network (e.g., a base station of the network), for example, if the comparison metric is above a threshold. The indication (e.g., firstindication) may indicate one or more beams from the second set of beams and one or more associated beams from the first set of beams (e.g., whose comparison metric is above a threshold). In examples, a beam from the second set of beams may have two comparison metrics above the threshold (e.g., the first indication may include the beam from the second set of beams and, in this example, the two associated beams from the first set of beams that are associated with the two comparison metrics.

[0139] The WTRU may send an indication (e.g., a second indication) to the network (e.g., a base station of the network), for example, if the comparison metric is above a threshold. The indication (e.g., second indication) may indicate one or more beams from the second set of beams whose comparison metric(s) (e.g., the metric(s) comparing the respective beam to (e.g., each beam, or all beams) in the first set of beams, and the respective, labelled scatterer(s) (e.g., MPCs)) are below a threshold, for example, a similar or same threshold, used for the first indication.

[0140] In this disclosure, the following terminology may be used. TRP and gNB may refer to the same meaning. Sensing measurements may refer to the measurements that determine the sensing characteristics of an object (e.g., AoA, ToA, sensing accuracy, RSRP, etc.). A sensing reference signal (RS) may refer to any of the RSs that can be used for sensing (e.g., PRS and CSI-RS).

[0141] A scatterer may be a set of MPCs that have similar attributes and may refer to a potential object (e.g., reflecting the similar set of MPCs) between the gNB / TRP and the WTRU. A sensed object may be an object identified by the WTRU using the sensing RS. A coverage area may denote an angular sector that may be covered by a beam or set of beams. The WTRU may rely on (pre)defined thresholds that are configured by the gNB.

[0142] Feature(s) associated with configurations for sensing RS(s) are provided herein. RS(s) signal may be associated with a specific beam or beams. The RS(s) may have one or more of the following configurations: one or more of a set of TCI states containing QCL relationships for the beams; time / frequency resources allocation; RE offset; or comb pattern (e.g., for PRS).

[0143] FIG. 3 depicts an example of simultaneous transmission of three beams. Transmitting multiple beams simultaneously (e.g., within the same OFDM symbols) may require multiplexing the beams over the same resources (e.g., frequency and code resources). In examples, the multiplexing of multiple beams may be performed using a frequency non-overlapping approach, a frequency-staggered approach, and / or a code-multiplexing approach.

[0144] Multiple beams may be multiplexed over different non-overlapping frequency resources. FIG. 4 depicts an example of multiple beams being transmitted over non-overlapping frequency resources. As shown in FIG. 4, multiple beams may be transmitted over blocks of resource elements (REs), where each beam may be assigned to a set of REs (e.g., beams 1, 2, and 3 of FIG. 3 may be assigned REs 1-20, 21-40, and 41 -60, respectively). The bandwidth may be divided between beams (e.g., all beams) and the sensing accuracy per beam may be reduced based on the Cramer-Rao lower bound (CRLB) (e.g., when transmitting multiple beams over non-overlapping frequency resources).

[0145] Multiple beams may be multiplexed in a frequency-staggered manner (e.g., which may involve interleaving the beams in a comb-like fashion). FIG. 5 depicts an example of multiple beams transmitted in a frequency-staggered manner.

[0146] For example, if there are two beams, one beam may be assigned to the even REs while the other beam may be assigned to the odd REs. This arrangement may ensure a staggered pattern of frequency allocation between the beams. In examples, the beams in FIG. 3 may be transmitted in a frequency- staggered manner as shown in FIG. 5. A maximum unambiguous ranging distance may be reduced (e.g., when using the frequency-staggered approach for multiplexing beams) as the maximum unambiguous ranging distance may be inversely proportional to the comb size.

[0147] Multiple beams may be multiplexed using code domain multiplexing. In examples, beams (e.g., all beams) may be spread over orthogonal codes, such as using orthogonal cover codes (OCC).

[0148] A bistatic sensing operation may be performed over two stages. The first stage of the bistatic sensing operation may use a first set of multiple beams that covers a wide area to perform an initial coarse sensing. The second stage of the bistatic sensing operation may use a second set of beams (e.g., a reduced number of beams that may be selected based on the report from the first stage) for a more fine sensing.

[0149] The two-stage bistatic sensing operation may reduce sensing latency (e.g., where a wide area or angle may be covered simultaneously using multiple beams) and / or may improve sensing accuracy of passive objects, for example, by assigning specific beams with a set of resources (e.g., BW and power) for fine sensing a set of scatterers, for example, that were coarse-sensed in the first stage.

[0150] Feature(s) associated with scatterers identification (e.g., labeling) are provided herein.

[0151] The WTRU may, for example, after receiving the beams, perform measurements to obtain / determine the channel responses associated with each of the beams. In examples, the WTRU may obtain / determine channel responses including one or more of: the channel impulse response (CIR), the channel frequency response (CFR), or the power delay profile (PDP). The WTRU may obtain / determine the channel responses of each beam separately (e.g., since beams are multiplexed and transmitted over separate resources, such as frequency and code resources).

[0152] The channel impulse response may be expressed as:

[0153] Where am tmay be the channel gain of the Z-th Multi-path Component (MPC) illuminating form the m-th scatterer, a(. ) may be the antenna factor, and 6m iand (pmi may be the AoA and AoD of the Z- th MPC illuminating form the m-th scatterer. Tmmay be the delay of the m-th scatterer (e.g., first MPC delay) and Tm imay be the delay of the Z-th MPC illuminating form the m-th scatterer.

[0154] The WTRU may use the obtained (e.g., determined) channel responses in order to identify specific scatterers (e.g., objects illuminating the beams). FIG. 6 depicts an example of MPCs identified as a set of scatterers. In examples, a scatterer may be identified using a set of MPCs exhibiting similarities in their attributes, such as angular (e.g., AoA, AoD), delay, power, etc. This may be performed using a clustering technique as shown in FIG. 6, where a set of MPCs are identified as a single cluster. As shown in FIG. 6, two scatterers may be identified based on their similarities in the delay, angle, and / or power.

[0155] Feature(s) associated with non-coherent measurements are provided herein.

[0156] After obtaining (e.g., determining) the channel responses of each beam and identifying the scatterers detected per beam, the WTRU may store the information related to each scatterer. In examples, the WTRU may store the channel response (e.g., PDP) of each scatterer in each beam (e.g., channel responses related to the MPCs identifying a specific scatterer).

[0157] The WTRU may perform non-coherent measurement(s) (e.g., on the stored information) to identify common scatterers between different beams. Common scatterers may be identified by performing non-coherent measurement(s) on the PDP of scatterer(s) (e.g., one scatterer) identified in a first beam and the PDP of other scatterer(s) (e.g., another scatterer) identified in a second beam. In examples, if the PDP of the fc-th scatterer in the nb-th beam may be expressed as Pnbik, and the PDP of the fc'-th scatterer in the nj,-th beam may be expressed as Pk>n' , the cross correlation between both PDPs (e.g., Pnb.kand Pk'nb< ) may be calculated as:Rpnb,k,pk'nb' ~ 'Pnb,kPk’,nb’ -

[0158] The two scatterers k and k' may be identified as the same scatterer, for example, fc"(e.g., given the correlation may be greater than a specific threshold (e.g., Th.R)). The scatterer k" may be detected by beams nband rib.

[0159] Feature(s) associated with a two-stage sensing operation (e.g., incorporating / using coarse sensing and fine sensing) are provided herein.

[0160] In examples, a first stage (e.g., stage 1) may comprise coarse sensing and may include one or more of the following.

[0161] The WTRU may be configured to, indicated to, and / or may determine to perform measurements and report a first stage (e.g., coarse) sensing report. The WTRU may be configured with information about a first set of RSs transmitted over a first set of beams transmitted by the gNB / TRP (e.g., via RRC, DCI, or MAC-CE). FIG. 7 depicts an example of first stage course sensing with a first set of beams. As shown in FIG. 7, multiple beams (e.g., the first set of beams) may be defined with narrow beamwidths to cover a wide area. The RSs may be defined as one of the DL RSs (e.g., PRS, CSI-RS, SSB, etc.). The WTRU may use the received first set of beams to perform one or more of the following: obtain / determine the channel responses; identify the set of scatterers (e.g., set of MPCs reflecting from the same object) detected by each beam; identify common scatterers between different beams, for example, using non-coherent measurements on the channel responses of each scatterer; associate each scatterer with at least one beam; perform sensing measurements (e.g., coarse sensing) on each of the identified scatterers; or report (e.g., to the gNB / TRP) a first stage coarse sensing report (e.g., including scatterers measurements and beams association to the TRP).

[0162] Bistatic sensing may comprise measuring sensing reference signals at the receiver (e.g., WTRU) that are transmitted by the transmitter (e.g., gNB / TRP) and scattered by objects in the environment. From the WTRU’s perspective, the WTRU may perform measurements on the received signals through different multipath components. The terms sensing, bistatic measurements, and bistatic sensing may be used interchangeably herein.

[0163] The WTRU may obtain / determine a first stage (e.g., coarse) sensing report using a first set of beams by performing one or more the following.

[0164] The WTRU may be configured to perform a first stage (e.g., coarse) scatterer(s) detection by receiving a set of sensing beams (e.g., via RRC) that cover a wide sector area (e.g., angular). The configuration (s) (e.g., received by the WTRU) may include one or more of the following: a configuration about a first set of beams for sensing; a RS configuration; or information about the first stage sensing report.

[0165] The configuration(s) may include configuration(s) about (e.g., indicating) a first set of beams for sensing (e.g., via RRC configuration, DCI, MAC-CE, etc.). The configuration(s) about the first set of beams for sensing may include, for example, one or more of: a set of TCI states containing QCL relationships for the beams, time / frequency resources allocation, measurements to perform, or a threshold.

[0166] The configuration(s) may include RS configuration(s), such as the sensing RS type (e.g., CSI-RS, PRS) or another dedicated sensing RS. RS configuration(s) may include (e.g., all) information about the resources, for example, the symbol and slot number, comb offset, comb size, number of RBs, etc.

[0167] The configuration(s) may include information about the first stage sensing report, including one or more of the following: scatterer(s) (e.g., set of MPCs) measurements to be indicated (e.g., association with beams, PDPs, CIR, CFR, or non-coherent measurements (e.g., cross-correlation)); the type of channel responses to be indicated (e.g., average PDPs, maximum PDPs, random PDPs, etc.); sensing measurements per scatterer to be measured and indicated (e.g., AoA, delays, RSRP, etc.); or one or more thresholds for the first stage sensing (e.g., minimum cross-correlation, minimum RSRP, etc.).

[0168] The WTRU may receive a set of reference signals for sensing on the configured time-frequency resources allocated over the first set of beams. The beams (e.g., the first set of beams) may be identified by a different set of reference signals (e.g., CSI-RS, PRS, etc.) In examples, if PRS is used for performing first stage sensing, multiple PRS signals may be transmitted over multiple beams that are multiplexed (e.g., non-overlapping frequencies, frequency-staggered approach, or code domain multiplexing) in a certain comb offsets.

[0169] The WTRU may obtain (e.g., determine) the channel response(s) associated with each beam. The channel response(s) associated with each beam may be one or more of: the channel impulse response (CIR), the channel frequency response (CFR), or the power delay profile (PDP). In examples, the WTRU may obtain (e.g., determine) channel responses, for example, the CIR, the CFR, and / or PDP. The channel responses may be used to obtain (e.g., determine) MPCs (e.g., that illuminate from scatterers located between the TRP and the WTRU in the direction of the transmitted beams).

[0170] The WTRU may identify one or more beam-specific scatterers (e.g., a set of MPCs with similar attributes) per beam (e.g., each beam in the first set of beams) using the received MPCs.

[0171] The WTRU may store and / or label the beam-specific scatterers in each beam (e.g., representing a beam-specific scatterer with a beam-specific scatterer ID). The WTRU may store the details related to each beam-specific scatterer in each beam. In examples, each beam-specific scatterer may be labeled with a beam-specific scatterer ID and information related to it may be stored (e.g., the channel response (e.g., PDP, CIR, or CFR)), and / or the angles, delay, and / or power measurements (e.g., AoA, ToA, or RSRP), as shown in Table 1 ). Table 1 depicts an example of information stored by the WTRU for respective scatterer(s) associated with each beam. The example of Table 1 includes three columns: the beam column containing beam identification (e.g., label or ID of each beam); the beam-specific scatterer column including the identification of each scatterer (e.g., label or ID of each scatterer detected in that beam); andthe characteristics column containing the characteristics of each scatterer, for example, the PDP, channel gain (a), AoA (e.g., 0), AoD (e.g., <p), etc., of each beam-specific scatterer.

[0172] Table 1 : information stored at the WTRU for scatterers in each beam.

[0173] The WTRU may perform non-coherent measurements on the channel responses of the beamspecific scatterers (e.g., set of MPCs) detected in beams (e.g., all beams). The non-coherent measurements may be used by the WTRU to detect common scatterers between different beams, for example, using the cross-correlation between the PDPs of the beams.

[0174] Non-coherent measurements may be defined by the cross correlation between the PDPs of at least two beam-specific scatterers associated with two different beams. In examples, the cross-correlation between the fc-th beam-specific scatterer detected by the nb-th beam and the k '-th beam-specific scatterer detected by thebeam may be captured by a cross-correlation parameter (e.g.,Rpnb.k,Pk'J-

[0175] If the cross-correlation between two beam-specific scatterers, e.g., k and k', in two different beams (e.g., nband nb' ), is above a specific threshold, the WTRU may identify both beam-specific scatterers as a single scatterer (e.g., beam-specific scatterers k and fc'may be identified as the same scatterer k").

[0176] The WTRU may determine one or more scatterers from the beam-specific scatterers and / or the detected common scatterers. The WTRU may label each scatterer (e.g., with a scatterer ID). The WTRU may associate each (e.g., labelled) scatterer (e.g., a set of MPCs) with a single beam or a set of beams (e.g., based on the non-coherent measurements). The WTRU may store the information related to each scatterer (e.g., as shown in Table 2). In examples, the WTRU perform one or more of the following:

[0177] The WTRU may associate a scatterer with two or more beams if the cross-correlation of a beamspecific scatterer detected by those beams is above a specific threshold. In examples, if a scatterer k" is determined to be the same scatterer as beam-specific scatterer k and k' for beams nband nb' (e.g., the cross-correlation between the two beam-specific scatterers may be above a specific threshold), then the WTRU may associate scatterer k" with beams nband rib.

[0178] If at least two beam-specific scatterers (e.g., set of MPCs) from at least two beams are identified as a single scatterer, the WTRU may provide a scatterer ID to (e.g., may label) the scatterer and / or may store its corresponding measurements.

[0179] The WTRU may store the scatterer ID and measurements of each scatterer using one or more of the following: store measurements (e.g., all of the measurements) of a specific scatterer, average the measurements of the scatterer across the associated beams (e.g., all the associated beams), or select at least one set of measurements obtained (e.g., determined) for a specific scatterer detected using a single beam (e.g., randomly or using a specific criterion, such as maximum received power).

[0180] The WTRU may store the measurements (e.g., all the measurements) of a specific scatterer (e.g., the beam-specific scatterer measurements) that are obtained (e.g., determined) in multiple beams (e.g., PDPs, angles, delays, power, etc., of the scatterer in each beam). If a scatterer is associated with one or more beams, the measurements of the scatterer for each beam may be the measurements of the beam-specific scatterer associated with the scatterer. In examples, the measurements for scatterer k" may be the measurements for beam-specific scatterer k of beam nband beam-specific scatterer k' of beam nbwhen scatterers k and k' are determined to be scatterer k" (e.g., and scatterer k" is associated with beam nband beam nb' ).

[0181] The WTRU may average the measurements of the scatterer across the associated beams (e.g., all the associated beams), for example, average PDPs Pfc(T), average angles (<9fc,fc), average delays (f), average power, etc. The average may be of the measurements of the beam-specific scatterers of the beams associated with the scatterer. In examples, for scatterer k", the average may be of beam-specific scatterer measurements for beam-specific scatterer k of beam nband beam-specific scatterer k' of beam nb' when scatterers k and k' are determined to be scatterer k" and scatterer k" may be associated with beam nband beam nb' )

[0182] The WTRU may select at least one set of measurements obtained (e.g., determined) for a specific scatterer using a single beam (e.g., based on random selection, or using a specific criterion, such as maximum received power).

[0183] Table 2 shows an example of the information stored by the WTRU after associating each scatterer with a set of beams. In examples, the Scatterer ID column may contain the identity of each scatterer (e.g., label or ID), the beams column may include the set of beams that are associated with the scatterer, and the characteristics column may contain the set of characteristics related to each scatterer (e.g., as described herein).

[0184] Table 2: information stored at the WTRU for scatterers associated with multiple beams and their measurements.

[0185] The WTRU may perform sensing measurements (e.g., SNR, RSRP, AoA, velocity, sensing accuracy (e.g., ranging or delay)) on the identified scatterers (e.g., each identified scatterer). In examples, bistatic measurements may be the set of measurements related to sensing. The WTRU may use the set of channel measurements (e.g., AoA, ToA, RSRP, etc.) to determine the detected scatterer’s relative location, velocity, ranging, sensing accuracy, etc.

[0186] The WTRU may prepare and send the first stage (e.g., coarse) sensing report over the UL data or control channels (e.g., PUSCH, PUCCH, etc.). The first stage (e.g., stage 1) sensing report may include one or more of the following: a list of identified scatterers (e.g., including their corresponding channel measurements, such as CIR, PDP, CFR, etc.); association(s) between scatterers and beams (e.g., scatterer k may be associated with Skbeams); non-coherent measurement(s) per beam and / or scatterer (e.g., cross-correlations, MSE, estimation error, number of iterations, etc.); sensing measurement(s) related to each scatterer (e.g., AoA, ToA, RSRP, etc.).

[0187] Table 3 shows an example of list measurements, where one or more of the measurements may be reported by the WTRU in the first stage (e.g., as described herein).

[0188] Table 3: example of the list of measurements reported by the WTRU in stage-1.

[0189] FIG. 8 depicts an example of WTRU operations in a first stage (e.g., course sensing) of a two- stage sensing method, where one or more of the illustrated actions may be performed as described herein.

[0190] FIG. 9 depicts an example of second stage (e.g., fine) sensing using a reduced number of beams.

[0191] In examples, a second stage (e.g., stage 2) may comprise fine sensing and may include one or more of the following.

[0192] The WTRU may be configured to, indicated to, and / or may determine to perform measurements and / or report a second stage (e.g., fine) sensing report. The WTRU may be configured with information about (e.g., indicating) a second set of RS transmitted over a second set of beams transmitted by the gNB / TRP (e.g., via RRC, DCI or MAC-CE). The second set of beams may be based on the first stage report from the WTRU (e.g., the second set of RS and beams may include a reduced number of RSs and beams). The second set of beams may be used to perform a more accurate sensing of each of the scatterers (e.g., fine sensing) reported in the first stage (e.g., stage 1). As shown in FIG. 9, the second set of beams may be defined with narrow beamwidths (e.g., that may share the same power resources for covering a reduced area or angle). The WTRU may use the report from stage 1 to perform one or more of the following on the received second set of beams: obtain (e.g., determine) the channel responses; identify the set of scatterers; verify scatterer(s) detected in stage 1 (e.g., by obtaining (e.g., determining) correlation with scatterer(s) detected in stage 1); perform second stage sensing measurements (e.g., fine sensing) on the identified scatterer(s) (e.g., each of the identified scatterers); or report to the network (e.g., gNB / TRP) a second stage fine sensing report with set of verified and / or unverified scatterer(s).

[0193] For stage 2, the TRP may run an iterative detection with the WTRU to sense the scatterer(s) identified in stage 1 (e.g., each of the scatterers identified in stage 1). The WTRU may perform one or more of the following.

[0194] The WTRU may be configurated to, indicated to, and / or may determine to generate a second stage (e.g., fine) sensing report for sending to the gNB / TRP (e.g., via RRC configuration, DCI, MAC-CE, etc.). The WTRU may obtain (e.g., determine) configuration information on second stage fine sensing thatincludes one or more of the following: a second set of sensing beams that are used to perform fine bistatic sensing (e.g., active TCI states, containing QCL relationships for the beams, time / frequency resources allocation etc.); RS(s) and / or beam(s) resources, such as the sensing RS type (e.g., CSI-RS, PRS), or another sensing RS; or information about the sensing report(s).

[0195] The WTRU may obtain (e.g., determine) configuration information that includes information about the resources (e.g., the symbol and slot number, comb offset, comb size, number of RBs, etc.).

[0196] The WTRU may obtain (e.g., determine) configuration information that includes information about the sensing reports. Information about the sensing reports may include one or more of: scatterers (e.g., set of MPCs) to be detected (e.g., number of scatterers or scatterers IDs); measurements to be indicated for unverified scatterers (e.g., PDPs, RSRP, etc.); sensing measurements per scatterer to be measured and indicated, (e.g., AoA, delays, RSRP, accuracy, etc.); or one or more thresholds for the second stage sensing (e.g., minimum scatterer verification, minimum RSRP, etc.).

[0197] The WTRU may receive a set of reference signals for sensing on the configured time-frequency resources allocated for the second set of beams.

[0198] The WTRU may obtain (e.g., determine) the channel responses associated with the second set of beams (e.g., CIR, CFR, or PDP).

[0199] The WTRU may verify the scatterers indicated (e.g., for fine sensing) by the gNB / TRP using the second set of beam(s). The WTRU may verify scatterers indicated (e.g., for fine sensing) by the gNB / TRP by performing one or more of the following.

[0200] The WTRU may obtain (e.g., determine) a metric comparing the channel responses in stage 1 and those in stage 2 (e.g., the cross-correlation between the PDP profiles of a specific scatterer from the first set of beams and second set of beams, for example, based on the scatterer ID and / or stored measurements). In examples, the WTRU may detect the beam-specific scatterers (e.g., using the second set of beams received in stage 2). The WTRU may obtain (e.g., determine) the scatterers corresponding channel responses (e.g., PDP, CIR, CFR). The WTRU may compare (e.g., using cross-correlations) the channel responses with the channel responses of scatterer(s) detected in stage 1 .

[0201] The WTRU may verify the scatterer being sensed. In examples, if the cross-correlation between the channel responses (e.g., PDPs) of a scatterer are detected using the second set of beam(s) (e.g., in stage 2) and / or the channel responses of a scatterer detected in the first set of beams (e.g., in stage 2) is above a specific threshold (e.g., indicated by the gNB / TRP), the WTRU may verify that the scatterer detected in stage 2 may be the same scatterer detected in stage 1 (e.g., the scatterer being sensed may be verified).

[0202] New scatterers (e.g., scatterers with measurements that do not match any of the stored scatterers from stage 1) may be considered as unverified scatterers. The WTRU may identify (e.g., label) unverified scatterer(s) and / or may store measurements (e.g., PDPs, etc.) associated with the unverified scatterer(s) (e.g., each unverified scatterer).

[0203] The WTRU may perform bistatic detection. Bistatic detection may include one or more of the following.

[0204] For a verified scatterer (e.g., a scatterer for which cross-correlation between PDPs from stage 1 and stage 2 for a specific scatterer is above a predefined threshold) the WTRU may perform bistatic sensing measurement(s). The WTRU may perform bistatic sensing measurements on the verified scatterer using the second set of beams (e.g., sensing measurements such as AoAs, ToA, RSRPs, sensing accuracy, etc.). The WTRU may (e.g., also) determine the location of the scatterer, speed (e.g., speed of the beam), etc.

[0205] For an unverified scatterer (e.g., a scatterer for which cross-correlation between PDPs from stage-1 and stage-2 for a specific scatterer is below a predefined threshold), the WTRU may perform bistatic measurements on unverified (e.g., non-verified) scatterer(s).

[0206] The WTRU may prepare and / or report a second stage sensing report (e.g., over the UL data or control channels (e.g., PUSCH, PUCCH, etc.)). The second stage sensing report may include one or more of the following: a list of identified scatterers and information associated with each (e.g., scatterer ID, verified, unverified, beams used for detection, etc.); non-coherent measurements for a (e.g., each) scatterer (e.g., cross-correlations, estimation error, etc.); sensing measurements related to each scatterer (e.g., AoA, ToA, RSRP, etc.); non-coherent measurements per beam and / or scatterer (e.g., crosscorrelations, MSE, estimation error, number of iterations etc.); or sensing measurements related to each scatterer, both verified and unverified (e.g.. AoA, ToA, RSRP, etc.).

[0207] Sensing measurements related to each scatterer (e.g., AoA, ToA, RSRP, etc.) may depend on whether the scatterer is verified. For verified scatterers (e.g., each verified scatterer), information included in the second stage sensing report may include information about the accuracy improvement (e.g., given accuracy of sensing as, the delta may be reported as Aas). For unverified scatterers (e.g., each unverified scatterer), information included in the second stage sensing report may include information about sensing accuracy.

[0208] Non-coherent measurements related to each scatterer (e.g., cross-correlations, estimation error, etc.) may depend on whether the scatterer is verified. For verified scatterers (e.g., each verified scatterer), information included in the second stage sensing report may include the delta of non-coherent measurements between stage 1 and stage 2 (e.g., AR, etc.). For unverified scatterers (e.g., each unverifiedscatterer), information included in the second stage sensing report may include full non-coherent measurements (e.g., as indicated by the gNB / TRP).

[0209] FIG. 10 depicts an example of WTRU operations in a second stage (e.g., fine sensing) of a two- stage sensing, where one or more of the illustrated actions may be performed.

[0210] FIG. 11 depicts an example message passing in a two-stage sensing, where one or more of the illustrated actions may be performed.

[0211] Feature(s) associated with specific scatterer and / or beam sensing are provided herein.

[0212] A WTRU may request sensing enhancements, for example, for a specific scatterer. The WTRU may (e.g., alternatively) be configured to, indicated to, and / or determine to perform measurements and / or report a more enhanced accuracy sensing report for a specific scatterer (e.g., by the gNB / TRP). The more enhanced accuracy sensing report (e.g., sensing enhancements for a specific scatterer) may be utilized when the requirements of sensing are not met, for example, the sensing accuracy of a scatterer (e.g., if sensing accuracy is below a sensing threshold).

[0213] The WTRU may receive a single beam that is transmitted (e.g., by the gNB / TRP) towards a specific known scatterer (e.g., known at the WTRU). The WTRU may perform bistatic sensing measurements (e.g., of the received single beam). The WTRU may report the bistatic sensing measurements to the network (e.g., the gNB / TRP).

[0214] The WTRU may be configurated to, indicated to, and / or may determine to perform sensing (e.g., via RRC configuration, DCI, MAC-CE, etc.). The WTRU may obtain / determine configuration information on sensing that includes one or more of the following: information about the scatterer to be reported, information about the sensing reports, or information about the beam that is transmitted.

[0215] The WTRU may obtain / determine configuration information on sensing that includes information about the scatterer to be reported (e.g., if available). Information about the scatterer to be reported may include one or more of: scatterer measurements (e.g., channel responses, PDP, CIR, etc.); scatterer- related measurements (e.g., AoA, ToA, RSRP, etc.); or the sensing beam associated with the specific scatterer used to perform bistatic sensing.

[0216] The WTRU may obtain / determine configuration information on sensing that includes information about the sensing reports. Information about the sensing reports may include one or more of: the specific scatterer(s) to be detected (e.g., scatterer ID); measurements to be indicated for scatterers (e.g., PDPs, RSRP, etc.); specific sensing measurements to be measured and indicated (e.g., AoA, delays, RSRP, accuracy, etc.); or one or more thresholds for the second stage sensing (e.g., minimum scatterer verification, minimum RSRP, etc.).

[0217] The WTRU may obtain / determine configuration information on sensing that includes information about the beam that is transmitted. Information about the beam that is transmitted may include one or more of: a specific beam configuration (e.g., the beam on which the gNB requests the WTRU to perform bistatic sensing, for example, active TCI states, containing QCL relationships for the beams, time / frequency resources allocation etc.); or RSs and beam resources, such as the sensing RS type (e.g., CSI-RS, PRS), or another sensing RS.

[0218] The gNB / TRP may indicate to the WTRU to perform (e.g., that the gNB / TRP wants the WTRU to perform) a bistatic sensing for a specific scatterer or set of scatterers (e.g., with prior knowledge of scatterers in the direction of the active beam). The configuration transmitted (e.g., by the gNB / TRP) may include information about a specific scatterer for which the gNB requires finer sensing (e.g., improved sensing accuracy). The gNB may configure the WTRU for bistatic sensing for a specific beam (e.g., without prior knowledge of any scatterers in the direction of the active beam).

[0219] FIG. 12 depicts an example of a gNB configuring a WTRU to perform sensing. The WTRU may request to perform sensing for a specific scatterer or a specific beam (e.g., via PUCCH, PUSCH, etc.). The WTRU may include the one or more of the following information in the request: information about the scatterer to be reported; or information about a beam (e.g., that the WTRU wants for sensing). Information about the scatterer to be reported may include one or more of the following: scatterer measurements (e.g., channel responses, for example, PDP, CIR, etc.); scatterer related measurements (e.g., AoA, ToA, RSRP, accuracy, etc.); or the sensing beam associated with the specific scatterer.

[0220] The WTRU may request (e.g., from the gNB) to perform a bistatic sensing for a specific scatterer or set of scatterers in the direction of a specific beam (e.g., which didn’t meet a specific sensing accuracy level, for example, as defined by a threshold). The WTRU may include information about the scatterer or set of scatterers that the WTRU wants to perform finer sensing (e.g., improved sensing accuracy). In examples, the WTRU may request bistatic sensing for a specific beam. In examples, bistatic sensing for a specific beam may be requested when the WTRU may be unable to detect any scatterer in the direction of a specific beam when transmitted and multiplexed with other beams (e.g., the requests separate sensing for that specific beam).

[0221] FIG. 13 depicts an example of a WTRU requesting sensing of a specific scatterer or beam.

[0222] The WTRU may receive one or more reference signals for sensing on the configured timefrequency resources allocated for at least one or more beams. The WTRU may perform one or more of the following.

[0223] The WTRU may obtain / determine the channel responses using the received beams (e.g., PDP, CIR, CFR).

[0224] The WTRU may identify and / or may label the set of scatterers in the direction of the active beam (e.g., each set of PDPs or MPCs are grouped and identified as single scatterer).

[0225] The WTRU may perform bistatic sensing measurements on the specific scatterer (e.g., set of PDPs or MPS that are grouped and identified as a single scatterer) using the received beam or set of beams (e.g., sensing measurements such as AoAs, ToA, RSRPs, sensing accuracy, etc.).

[0226] The WTRU may prepare and / or report a sensing report over the UL data or control channels (e.g., PUSCH, PUCCH, etc.). The sensing report may include one or more of the following: a list of identified scatterer(s) (e.g., scatterer ID(s)); scatterers related channel responses (e.g., set of channel responses related to a specific scatterer and / or delta channel responses, such as the difference in channel responses between a previous stage sensing and the current stage sensing, for example, APDP, ACIR, ACFR, etc.); sensing measurements related to each scatterer (e.g., AoA, ToA, RSRP, etc.); or correction measurements (e.g., AAoA, AToA, ARSRP, Aaccuracy, etc.).

[0227] Although features and elements described above are described in particular combinations, each feature or element may be used alone without the other features and elements of the preferred embodiments, or in various combinations with or without other features and elements.

[0228] Although the implementations described herein may consider 3GPP specific protocols, it is understood that the implementations described herein are not restricted to this scenario and may be applicable to other wireless systems. For example, although the solutions described herein consider LTE, LTE-A, New Radio (NR) or 5G specific protocols, it is understood that the solutions described herein are not restricted to this scenario and are applicable to other wireless systems as well.

[0229] The processes described above may be implemented in a computer program, software, and / or firmware incorporated in a computer-readable medium for execution by a computer and / or processor. Examples of computer-readable media include, but are not limited to, electronic signals (transmitted over wired and / or wireless connections) and / or computer-readable storage media. Examples of computer- readable storage media include, but are not limited to, a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as, but not limited to, internal hard disks and removable disks, magneto-optical media, and / or optical media such as compact disc (CD)-ROM disks, and / or digital versatile disks (DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, terminal, base station, RNC, and / or any host computer.

Claims

CLAIMSWhat is claimed is:1 . A wireless transmit / receive unit (WTRU) comprising: a processor configured to: perform first sensing associated with a first set of beams; determine a scatterer based on the first sensing; determine that at least a first beam, from the first set of beams, is associated with the scatterer and a first characteristic associated with at least the first beam; send a first report, wherein the first report indicates the scatterer, at least the first beam associated with the scatterer, and the first characteristic associated with at least the first beam; perform second sensing associated with a second set of beams; determine a second beam, from the second set of beams, and a second characteristic associated with the second beam; determine that a cross-correlation associated with the first characteristic and the second characteristic satisfies a threshold; and send a second report, wherein the second report includes: an indication that the scatterer is verified, and an indication of the second beam.

2. The WTRU of claim 1 , wherein the second report further indicates the second characteristic associated with the second beam.

3. The WTRU of claim 1 , wherein the first set of beams comprises a first number of beams and the second set of beams comprises a second number of beams, wherein the second number of beams is less than the first number of beams, and wherein at least the first beam is within the second set of beams.

4. The WTRU of claim 1 , wherein: the first characteristic associated with at least the first beam is at least one of: a first channel impulse response (CIR); a first channel frequency response (CFR); or a first power delay profile (PDP); andthe second characteristic associated with the second beam is at least one of: a second CIR; a second CFR; or a second PDP.

5. The WTRU of claim 1 , wherein the processor is further configured to perform a bistatic sensing measurement associated with the second beam, wherein the bistatic sensing measurement associated with the second beam comprises at least one of: a delay; an angle of arrival; or a received power, and wherein the second report comprises the bistatic sensing measurement.

6. The WTRU of claim 5, wherein the bistatic sensing measurement comprises relative differences between measurements obtained using the first set of beams and the second set of beams.

7. The WTRU of claim 1 , wherein the threshold is a first threshold, and wherein the determination that at least the first beam of the first set of beams is associated with the scatterer further comprises the processor being configured to: determine that the scatterer is associated with a second beam from the first set of beams; perform a cross-correlation associated with the first beam of the first set of beams and the second beam of the first set of beams; and determine that the cross-correlation associated with the first beam of the first set of beams and the second beam of the first set of beams satisfies a second threshold.

8. The WTRU of claim 1 , wherein the second set of beams is selected from the first set of beams based on an association between the scatterer and the first set of beams.

9. The WTRU of claim 3, wherein the first beam is associated with a first power and the second beam is associated with a second power.

10. A method comprising: performing first sensing associated with a first set of beams; determining a scatterer based on the first sensing; determining that at least a first beam, from the first set of beams, is associated with the scatterer and a first characteristic associated with at least the first beam;sending a first report, wherein the first report indicates the scatterer, at least the first beam associated with the scatterer, and the first characteristic associated with at least the first beam; performing second sensing associated with a second set of beams; determining a second beam, from the second set of beams, and a second characteristic associated with the second beam; determining that a cross-correlation associated with the first characteristic and the second characteristic satisfies a threshold; and sending a second report, wherein the second report includes: an indication that the scatterer is verified, and an indication of the second beam.11 . The method of claim 10, wherein the second report further indicates the second characteristic associated with the second beam.

12. The method of claim 10, wherein the first set of beams comprises a first number of beams and the second set of beams comprises a second number of beams, wherein the second number of beams is less than the first number of beams, and wherein at least the first beam is within the second set of beams.

13. The method of claim 10, wherein: the first characteristic associated with at least the first beam is at least one of: a first channel impulse response (Cl R); a first channel frequency response (CFR); or a first power delay profile (PDP); and the second characteristic associated with the second beam is at least one of: a second CIR; a second CFR; or a second PDP.

14. The method of claim 10, further comprising performing a bistatic sensing measurement associated with the second beam, wherein the bistatic sensing measurement associated with the second beam comprises at least one of: a delay; an angle of arrival; or a received power, and wherein the second report comprises the bistatic sensing measurement.

15. The method of claim 14, wherein the bistatic sensing measurement comprises relative differences between measurements obtained using the first set of beams and the second set of beams.

16. The method of claim 10, wherein the threshold is a first threshold, and wherein the determining that at least the first beam of the first set of beams is associated with the scatterer further comprises the method comprising: determining that the scatterer is associated with a second beam from the first set of beams; performing a cross-correlation associated with the first beam of the first set of beams and the second beam of the first set of beams; and determining that the cross-correlation associated with the first beam of the first set of beams and the second beam of the first set of beams satisfies a second threshold.

17. The method of claim 10, wherein the second set of beams is selected from the first set of beams based on an association between the scatterer and the first set of beams.

18. The method of claim 12, wherein the first beam is associated with a first power and the second beam is associated with a second power.

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