Partial Random Access Channel Procedure

Abstract

In one embodiment, a serving BS for the UE may transmit a PDCCH communication to the UE. The PDCCH communication triggers a partial RACH procedure, which results in a RACH transmission. In some designs, the RACH transmission is for positioning, and the positioning measurements are performed at the serving BS and (possibly) at one or more non-serving BSs. In some designs, measurement data based on the positioning measurements is conveyed to a location estimation entity (e.g., an LMF) that performs a position estimation for the UE.

Description

Claim of Priority

[0001] Cross - Reference to Related Applications

[0001] This patent application claims the benefit of U.S. Provisional Application No. 63 / 027,694, filed May 20, 2020, and U.S. Non - Provisional Application No. 17 / 319,416, filed May 13, 2021, both of which are assigned to the assignee of this application and are hereby incorporated by reference in their entirety.

Technical Field

[0002]

[0002] Aspects of the present disclosure generally relate to partial random access channel (RACH) procedures.

Background Art

[0003]

[0003] Wireless communication systems have evolved through various generations, including first - generation analog wireless telephone services (1G), second - generation (2G) digital wireless telephone services (including intermediate 2.5G networks), third - generation (3G) high - speed data, Internet - enabled wireless services, and fourth - generation (4G) services (e.g., LTE (registered trademark) or WiMax (registered trademark)). Currently, there are many different types of wireless communication systems in use, including cellular and personal communication service (PCS) systems. Examples of known cellular systems include the cellular analog advanced mobile phone system (AMPS), and digital cellular systems based on code - division multiple access (CDMA), frequency - division multiple access (FDMA), time - division multiple access (TDMA), and mobile access - specific variants of TDMA such as the Global System for Mobile (GSM (registered trademark)).

[0004]

[0004] The fifth-generation (5G) wireless standard, called New Radio (NR), enables, among other improvements, higher data transfer speeds, a greater number of connections, and better coverage. The 5G standard by the Next Generation Mobile Networks Alliance is designed to provide data rates of tens of megabits per second to each of tens of thousands of users and data rates of one gigabit per second to tens of workers on an office floor. Hundreds of thousands of simultaneous connections should be supported to support large wireless deployments. Thus, the spectral efficiency of 5G mobile communications should be significantly extended compared to current 4G standards. Further, signaling efficiency should be extended and latency should be significantly reduced compared to current standards.

SUMMARY OF THE INVENTION

[0005]

[0005] The following presents a simplified summary relating to one or more aspects disclosed herein. Accordingly, the following summary should not be considered an extensive overview relating to all contemplated aspects, nor should the following summary be considered to identify key or critical elements relating to all contemplated aspects or to delineate the scope relating to any particular aspect. Thus, the following summary has the sole purpose of presenting in a simplified form some concepts relating to one or more aspects relating to the mechanisms disclosed herein prior to the forms for implementing the inventions presented below.

[0006]

[0006] In one aspect, a method of operating a user equipment (UE) includes receiving physical downlink control channel (PDCCH) communications and, in response to the PDCCH communications, triggering a partial random access channel (RACH) procedure.

[0007]

[0007] In some aspects, the partial RACH procedure includes transmitting a RACH signal for positioning.

[0008]

[0008] In some aspects, the positioning RACH signal targets the UE's serving base station (BS) and at least one non-serving BS of the UE.

[0009]

[0009] In some aspects, triggering is in response to the configuration of PDCCH communication.

[0010]

[0010] In some aspects, triggering is in response to at least one field of PDCCH communication.

[0011]

[0011] In some aspects, at least one field comprises a radio network temporary identifier (RNTI), or at least one field is part of downlink control information (DCI) communication, or any combination thereof.

[0012]

[0012] In some aspects, at least one field in DCI communication has a first value, and the partial RACH procedure comprises RACH transmission with a first configuration based on the first value, and further comprises receiving another DCI communication in which at least one field has a second value, and this another DCI communication triggers another partial RACH procedure comprising another RACH transmission with a second configuration based on the second value.

[0013]

[0013] In some aspects, triggering is in response to the size of PDCCH communication.

[0014]

[0014] In some aspects, the partial RACH procedure is a partial four-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0015]

[0015] In some aspects, the partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or physical uplink shared channel (PUSCH) communication.

[0016]

[0016] In some aspects, the UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between receiving and triggering.

[0017]

[0017] In some aspects, the partial RACH procedure comprises RACH transmission transmitted on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the partial RACH procedure comprises RACH transmission transmitted via one or more frequency layers for each of one or more RACH occasions, the number of one or more frequency layers being based on the number of configured frequency layers for the UE, or the partial RACH procedure comprises transmission of repetition of the RACH preamble over a plurality of RACH occasions, or any combination thereof.

[0018]

[0018] In some aspects, the RACH procedure is based on a timing offset indicated via PDCCH communication.

[0019]

[0019] In some aspects, the RACH procedure is implemented via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH procedure is implemented via a shared spectrum shared by a plurality of RATs.

[0020]

[0020] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger the downlink part of the joint uplink and downlink positioning procedure.

[0021]

[0021] In one aspect, a method of operating a serving base station (BS) of a user equipment (UE) includes transmitting physical downlink control channel (PDCCH) communication configured to trigger a partial random access channel (RACH) procedure to the UE, and receiving an RACH transmission from the UE in response to the PDCCH communication.

[0022]

[0022] In some aspects, the RACH transmission is for positioning and further includes performing one or more positioning measurements on the RACH transmission.

[0023]

[0023] In some aspects, the RACH signal for positioning targets at least one non-serving BS of the UE and the serving BS of the UE.

[0024]

[0024] In some aspects, the method includes notifying at least one non-serving BS or a location management function (LMF) of a partial RACH procedure to facilitate the at least one non-serving BS performing positioning measurements on the RACH transmission.

[0025]

[0025] In some aspects, the method includes sending measurement data based on one or more positioning measurements to a location estimation entity.

[0026]

[0026] In some aspects, the PDCCH communication is configured to trigger a partial RACH procedure based on the configuration of the PDCCH communication.

[0027]

[0027] In some aspects, the PDCCH communication is configured to trigger a partial RACH procedure based on at least one field of the PDCCH communication.

[0028]

[0028] In some aspects, the at least one field comprises a radio network temporary identifier (RNTI), or the at least one field is part of a downlink control information (DCI) communication, or any combination thereof.

[0029]

[0029] In some aspects, at least one field in the DCI communication has a first value, the RACH transmission is configured with a first configuration based on the first value, and further comprises transmitting another DCI communication in which at least one field has a second value, and this another DCI communication is configured to trigger another partial RACH procedure having another RACH transmission with a second configuration based on the second value.

[0030]

[0030] In some aspects, the PDCCH communication is configured to trigger a partial RACH procedure based on the size of the PDCCH communication.

[0031]

[0031] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only receiving a RACH preamble without a RACH response to the RACH preamble.

[0032]

[0032] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises receiving a RACH preamble and a PUSCH communication without a RACH response to the RACH preamble or the PUSCH communication.

[0033]

[0033] In some aspects, the UE does not have an active SRS configuration for triggering the transmission of sounding reference signals (SRS) for positioning between transmitting and receiving.

[0034]

[0034] In some aspects, RACH transmissions are received on one or more beams corresponding to multiple synchronization signal blocks (SSBs), or RACH transmissions are received via one or more frequency layers for each of one or more RACH occasions, where the number of one or more frequency layers is based on the number of configured frequency layers for the UE, or RACH transmissions comprise repetitions of RACH preambles over multiple RACH occasions, or any combination thereof.

[0035]

[0035] In some aspects, the RACH procedure may be based on a timing offset indicated via PDCCH communication.

[0036]

[0036] In some aspects, RACH transmissions are received via an authorized spectrum approved for a particular radio access technology (RAT), or RACH transmissions are received via a shared spectrum shared by multiple RATs.

[0037]

[0037] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger the downlink part of the joint uplink and downlink positioning procedure.

[0038]

[0038] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure.

[0039]

[0039] In one aspect, a method of operating a non-serving base station (BS) of a user equipment (UE) includes receiving, from the UE, an indication of a random access channel (RACH) transmission associated with a partial RACH procedure, and receiving the RACH transmission based on the indication.

[0040]

[0040] In some aspects, the RACH transmission is for positioning, and further includes performing one or more positioning measurements on the RACH transmission.

[0041]

[0041] In some aspects, the method includes sending measurement data based on one or more positioning measurements to a position estimation entity.

[0042]

[0042] In some aspects, the partial RACH procedure is a partial four-step RACH procedure, where the partial RACH procedure includes only transmitting a RACH preamble without a RACH response to the RACH preamble.

[0043]

[0043] In some aspects, the partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure includes transmitting a RACH preamble and a physical uplink shared channel (PUSCH) communication without a RACH response to the RACH preamble or the PUSCH communication.

[0044]

[0044] In some aspects, the RACH transmission is received via an authorized spectrum authorized for a particular radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0045]

[0045] In one aspect, a method of operating a location estimation entity includes receiving measurement data based on one or more positioning measurements performed by a set of base stations (BSs) on a random access channel (RACH) transmission for positioning from a user equipment (UE), and determining a positioning estimate of the UE based at least in part on the measurement data.

[0046]

[0046] In some aspects, the RACH transmission is associated with a partial RACH procedure.

[0047]

[0047] In some aspects, the partial RACH procedure is triggered by physical downlink control channel (PDCCH) communication from the serving BS of the UE.

[0048]

[0048] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0049]

[0049] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the transmission of a RACH preamble and physical uplink shared channel (PUSCH) communication without a RACH response to the RACH preamble or the PUSCH communication.

[0050]

[0050] In some aspects, the RACH transmission for positioning is transmitted by the UE via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0051]

[0051] In one aspect, a user equipment (UE) includes a memory, a communication interface, and at least one processor communicatively coupled to the memory and the communication interface, the at least one processor being configured to receive physical downlink control channel (PDCCH) communication via the communication interface and trigger a partial random access channel (RACH) procedure in response to the PDCCH communication.

[0052]

[0052] In some aspects, the partial RACH procedure comprises transmitting a RACH signal for positioning.

[0053]

[0053] In some aspects, the RACH signal for positioning targets the serving base station (BS) of the UE and at least one non-serving BS of the UE.

[0054]

[0054] In some aspects, triggering is in response to the configuration of the PDCCH communication.

[0055]

[0055] In some aspects, triggering is in response to at least one field of the PDCCH communication.

[0056]

[0056] In some aspects, the at least one field comprises a radio network temporary identifier (RNTI), or the at least one field is part of downlink control information (DCI) communication, or any combination thereof.

[0057]

[0057] In some aspects, at least one field in the DCI communication has a first value, the partial RACH procedure comprises a RACH transmission having a first configuration based on the first value, and further comprises receiving, via the communication interface, another DCI communication in which the at least one field has a second value, the another DCI communication triggering another partial RACH procedure comprising another RACH transmission having a second configuration based on the second value.

[0058]

[0058] In some aspects, triggering responds to the size of PDCCH communication.

[0059]

[0059] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0060]

[0060] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication.

[0061]

[0061] In some aspects, the UE does not have an active SRS configuration for triggering the transmission of a sounding reference signal (SRS) for positioning between receiving and triggering.

[0062]

[0062] In some aspects, the partial RACH procedure comprises a RACH transmission transmitted on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the partial RACH procedure comprises a RACH transmission transmitted via one or more frequency layers for each of one or more RACH occasions, the number of one or more frequency layers being based on the number of configured frequency layers for the UE, or the partial RACH procedure comprises the repeated transmission of RACH preambles over a plurality of RACH occasions, or any combination thereof.

[0063]

[0063] In some aspects, the RACH procedure is based on a timing offset indicated via PDCCH communication.

[0064]

[0064] In some aspects, the RACH procedure is performed via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH procedure is performed via a shared spectrum shared by multiple RATs.

[0065]

[0065] In some aspects, the partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger a downlink part of the joint uplink and downlink positioning procedure.

[0066]

[0066] In some aspects, the partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure.

[0067]

[0067] In one aspect, a base station includes a memory, a communication interface, and at least one processor communicatively coupled to the memory and the communication interface, and the at least one processor is configured to cause the communication interface to transmit physical downlink control channel (PDCCH) communication configured to trigger a partial random access channel (RACH) procedure to a UE, and to receive, from the UE in response to the PDCCH communication, an RACH transmission via the communication interface.

[0068]

[0068] In some aspects, the RACH transmission is for positioning and further includes performing one or more positioning measurements on the RACH transmission.

[0069]

[0069] In some aspects, the RACH signal for positioning targets at least one non-serving BS of the UE and the serving BS of the UE.

[0070]

[0070] In some aspects, at least one processor is further configured to notify at least one non-serving BS or a location management function (LMF) of a partial RACH procedure to facilitate the at least one non-serving BS performing positioning measurements on RACH transmissions.

[0071]

[0071] In some aspects, at least one processor is further configured to cause a communication interface to send measurement data based on one or more positioning measurements to a position estimation entity.

[0072]

[0072] In some aspects, PDCCH communication is configured to trigger a partial RACH procedure based on the configuration of the PDCCH communication.

[0073]

[0073] In some aspects, PDCCH communication is configured to trigger a partial RACH procedure based on at least one field of the PDCCH communication.

[0074]

[0074] In some aspects, at least one field comprises a radio network temporary identifier (RNTI), or at least one field is part of downlink control information (DCI) communication, or any combination thereof.

[0075]

[0075] In some aspects, at least one field in DCI communication has a first value, the RACH transmission is configured with a first configuration based on the first value, and further comprises causing a communication interface to send another DCI communication in which at least one field has a second value, the another DCI communication being configured to trigger another partial RACH procedure comprising another RACH transmission having a second configuration based on the second value.

[0076]

[0076] In some aspects, the PDCCH communication is configured to trigger a partial RACH procedure based on the size of the PDCCH communication.

[0077]

[0077] In some aspects, the partial RACH procedure is a partial four-step RACH procedure, where the partial RACH procedure comprises only reception of a RACH preamble without a RACH response to the RACH preamble.

[0078]

[0078] In some aspects, the partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises reception of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication.

[0079]

[0079] In some aspects, the UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between transmitting and receiving.

[0080]

[0080] In some aspects, the RACH transmission is received on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the RACH transmission is received via one or more frequency layers for each of one or more RACH occasions, the number of one or more frequency layers being based on the number of configured frequency layers for the UE, or the RACH transmission comprises repetitions of RACH preambles over a plurality of RACH occasions, or any combination thereof.

[0081]

[0081] In some aspects, the RACH procedure may be based on a timing offset indicated via PDCCH communication.

[0082]

[0082] In some aspects, the RACH transmission is received via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0083]

[0083] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger the downlink part of the joint uplink and downlink positioning procedure.

[0084]

[0084] In one aspect, a base station includes a memory, a communication interface, and at least one processor communicatively coupled to the memory and the communication interface, the at least one processor being configured to receive, from a UE via the communication interface, an indication of a RACH transmission associated with a partial random access channel (RACH) procedure, and to receive, via the communication interface, a RACH transmission based on the indication.

[0085]

[0085] In some aspects, the RACH transmission is for positioning and further comprises performing one or more positioning measurements on the RACH transmission.

[0086]

[0086] In some aspects, the at least one processor is further configured to cause the communication interface to send measurement data based on one or more positioning measurements to a position estimation entity.

[0087]

[0087] In some aspects, the partial RACH procedure is a partial four-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0088]

[0088] In some aspects, the partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises transmitting a RACH preamble and PUSCH communication without a RACH response for the RACH preamble or physical uplink shared channel (PUSCH) communication.

[0089]

[0089] In some aspects, the RACH transmission is received via an authorized spectrum authorized for a particular radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0090]

[0090] In one aspect, the position estimation entity includes a memory, a communication interface, and at least one processor communicatively coupled to the memory and the communication interface, and the at least one processor is configured to receive, via the communication interface, measurement data based on one or more positioning measurements performed by a set of base stations (BSs) on a random access channel (RACH) transmission for positioning from a user equipment (UE), and to determine a positioning estimate of the UE based at least in part on the measurement data.

[0091]

[0091] In some aspects, the RACH transmission is associated with a partial RACH procedure.

[0092]

[0092] In some aspects, the partial RACH procedure is triggered by physical downlink control channel (PDCCH) communication from the serving BS of the UE.

[0093]

[0093] In some aspects, the partial RACH procedure is a partial four-step RACH procedure, where the partial RACH procedure comprises transmitting only the RACH preamble without a RACH response to the RACH preamble.

[0094]

[0094] In some aspects, the partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises transmitting a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or physical uplink shared channel (PUSCH) communication.

[0095]

[0095] In some aspects, the RACH transmission for positioning is transmitted by a UE via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0096]

[0096] In one aspect, a user equipment (UE) includes means for receiving physical downlink control channel (PDCCH) communication and means for triggering a partial random access channel (RACH) procedure in response to the PDCCH communication.

[0097]

[0097] In some aspects, the partial RACH procedure comprises transmitting a RACH signal for positioning.

[0098]

[0098] In some aspects, the RACH signal for positioning targets at least one non-serving BS of the UE and a serving base station (BS) of the UE.

[0099]

[0099] In some aspects, triggering is in response to the configuration of the PDCCH communication.

[0100]

[0100] In some aspects, triggering is in response to at least one field of the PDCCH communication.

[0101]

[0101] In some aspects, the at least one field comprises a radio network temporary identifier (RNTI), or the at least one field is part of downlink control information (DCI) communication, or any combination thereof.

[0102]

[0102] In some aspects, at least one field in DCI communication has a first value, and the partial RACH procedure comprises RACH transmission having a first configuration based on the first value, and further comprises means for receiving another DCI communication in which at least one field has a second value, and this another DCI communication triggers another partial RACH procedure comprising another RACH transmission having a second configuration based on the second value.

[0103]

[0103] In some aspects, triggering responds to the size of PDCCH communication.

[0104]

[0104] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0105]

[0105] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication.

[0106]

[0106] In some aspects, the UE does not have an active SRS configuration for triggering the transmission of a sounding reference signal (SRS) for positioning between receiving and triggering.

[0107]

[0107] In some aspects, the partial RACH procedure comprises RACH transmissions sent on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the partial RACH procedure comprises RACH transmissions sent via one or more frequency layers for each of one or more RACH occasions, where the number of one or more frequency layers is based on the number of configured frequency layers for the UE, or the partial RACH procedure comprises transmissions of repetitions of RACH preambles over a plurality of RACH occasions, or any combination thereof.

[0108]

[0108] In some aspects, the RACH procedure is based on a timing offset indicated via PDCCH communication.

[0109]

[0109] In some aspects, the RACH procedure is carried out via an authorized spectrum authorized for a particular radio access technology (RAT), or the RACH procedure is carried out via a shared spectrum shared by a plurality of RATs.

[0110]

[0110] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger the downlink part of the joint uplink and downlink positioning procedure.

[0111]

[0111] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure.

[0112]

[0112] In one aspect, a base station includes means for transmitting physical downlink control channel (PDCCH) communication configured to trigger a partial random access channel (RACH) procedure to a UE, and means for receiving RACH transmissions from the UE in response to the PDCCH communication.

[0113]

[0113] In some aspects, the RACH transmission is for positioning, and further comprises means for performing one or more positioning measurements on the RACH transmission.

[0114]

[0114] In some aspects, the RACH signal for positioning targets the serving BS of the UE and at least one non-serving BS of the UE.

[0115]

[0115] In some aspects, the method includes means for notifying at least one non-serving BS or a location management function (LMF) of a partial RACH procedure to facilitate the at least one non-serving BS performing positioning measurements on the RACH transmission.

[0116]

[0116] In some aspects, the method includes means for sending measurement data based on one or more positioning measurements to a position estimation entity.

[0117]

[0117] In some aspects, the PDCCH communication is configured to trigger a partial RACH procedure based on the configuration of the PDCCH communication.

[0118]

[0118] In some aspects, the PDCCH communication is configured to trigger a partial RACH procedure based on at least one field of the PDCCH communication.

[0119]

[0119] In some aspects, at least one field comprises a radio network temporary identifier (RNTI), or at least one field is part of downlink control information (DCI) communication, or any combination thereof.

[0120]

[0120] In some aspects, at least one field in DCI communication has a first value, the RACH transmission is configured with a first configuration based on the first value, and further comprises means for transmitting another DCI communication in which at least one field has a second value, and this another DCI communication is configured to trigger another partial RACH procedure having another RACH transmission with a second configuration based on the second value.

[0121]

[0121] In some aspects, the PDCCH communication is configured to trigger a partial RACH procedure based on the size of the PDCCH communication.

[0122]

[0122] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only the reception of a RACH preamble without a RACH response to the RACH preamble.

[0123]

[0123] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the reception of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication.

[0124]

[0124] In some aspects, the UE does not have an active SRS configuration for triggering the transmission of a sounding reference signal (SRS) for positioning between transmitting and receiving.

[0125]

[0125] In some aspects, the RACH transmission is received on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the RACH transmission is received via one or more frequency layers for each of one or more RACH occasions, the number of one or more frequency layers being based on the number of configured frequency layers for the UE, or the RACH transmission comprises repetitions of RACH preambles over a plurality of RACH occasions, or any combination thereof.

[0126]

[0126] In some aspects, the RACH procedure may be based on a timing offset indicated via PDCCH communication.

[0127]

[0127] In some aspects, the RACH transmission is received via an authorized spectrum authorized for a particular radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by a plurality of RATs.

[0128]

[0128] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger the downlink part of the joint uplink and downlink positioning procedure.

[0129]

[0129] In one aspect, a base station includes means for receiving from a UE an indication of a RACH transmission associated with a partial random access channel (RACH) procedure, and means for receiving the RACH transmission based on the indication.

[0130]

[0130] In some aspects, the RACH transmission is for positioning and further comprises means for performing one or more positioning measurements on the RACH transmission.

[0131]

[0131] In some aspects, the method includes means for sending measurement data based on one or more positioning measurements to a positioning entity.

[0132]

[0132] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0133]

[0133] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or physical uplink shared channel (PUSCH) communication.

[0134]

[0134] In some aspects, the RACH transmission is received via an authorized spectrum authorized for a particular radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0135]

[0135] In one aspect, the positioning entity includes means for receiving measurement data based on one or more positioning measurements performed by a set of base stations (BSs) on a random access channel (RACH) transmission for positioning from a user equipment (UE), and means for determining a positioning estimate of the UE based at least in part on the measurement data.

[0136]

[0136] In some aspects, the RACH transmission is associated with a partial RACH procedure.

[0137]

[0137] In some aspects, the partial RACH procedure is triggered by physical downlink control channel (PDCCH) communication from the serving BS of the UE.

[0138]

[0138] In some aspects, the partial RACH procedure is a partial four-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0139]

[0139] In some aspects, the partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises the transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or physical uplink shared channel (PUSCH) communication.

[0140]

[0140] In some aspects, the RACH transmission for positioning is transmitted by a user equipment (UE) via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0141]

[0141] In one aspect, a non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to receive physical downlink control channel (PDCCH) communication and, in response to the PDCCH communication, trigger a partial random access channel (RACH) procedure.

[0142]

[0142] In some aspects, the partial RACH procedure comprises the transmission of a RACH signal for positioning.

[0143]

[0143] In some aspects, the RACH signal for positioning targets at least one non-serving BS of the UE and a serving base station (BS) of the UE.

[0144]

[0144] In some aspects, triggering is in response to the configuration of the PDCCH communication.

[0145]

[0145] In some aspects, triggering responds to at least one field of PDCCH communication.

[0146]

[0146] In some aspects, at least one field comprises a radio network temporary identifier (RNTI), or at least one field is part of downlink control information (DCI) communication, or any combination thereof.

[0147]

[0147] In some aspects, at least one field in DCI communication has a first value, and the partial RACH procedure comprises RACH transmission with a first configuration based on the first value, and further comprises receiving another DCI communication in which at least one field has a second value, and this another DCI communication triggers another partial RACH procedure comprising another RACH transmission with a second configuration based on the second value.

[0148]

[0148] In some aspects, triggering responds to the size of PDCCH communication.

[0149]

[0149] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0150]

[0150] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or physical uplink shared channel (PUSCH) communication.

[0151]

[0151] In some aspects, the UE does not have an active SRS configuration for triggering the transmission of a sounding reference signal (SRS) for positioning between receiving and triggering.

[0152]

[0152] In some aspects, the partial RACH procedure comprises RACH transmissions that are sent on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the partial RACH procedure comprises RACH transmissions that are sent via one or more frequency layers for each of one or more respective RACH occasions, the number of one or more frequency layers being based on the number of configured frequency layers for the UE, or the partial RACH procedure comprises the transmission of repetitions of RACH preambles over a plurality of RACH occasions, or any combination thereof.

[0153]

[0153] In some aspects, the RACH procedure is based on a timing offset indicated via PDCCH communication.

[0154]

[0154] In some aspects, the RACH procedure is carried out via an authorized spectrum authorized for a particular radio access technology (RAT), or the RACH procedure is carried out via a shared spectrum shared by a plurality of RATs.

[0155]

[0155] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger the downlink part of the joint uplink and downlink positioning procedure.

[0156]

[0156] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure.

[0157]

[0157] In one aspect, a non-transitory computer-readable medium storing computer-executable instructions that, when executed by a base station, cause the base station to transmit physical downlink control channel (PDCCH) communications configured to trigger a partial random access channel (RACH) procedure to a UE and to receive an RACH transmission from the UE in response to the PDCCH communications.

[0158]

[0158] In some aspects, the RACH transmission is for positioning and further comprises performing one or more positioning measurements on the RACH transmission.

[0159]

[0159] In some aspects, the RACH signal for positioning targets the UE's serving BS and at least one non-serving BS of the UE.

[0160]

[0160] In some aspects, one or more instructions further cause the base station to notify at least one non-serving BS or a location management function (LMF) of the partial RACH procedure to facilitate the at least one non-serving BS performing positioning measurements on the RACH transmission.

[0161]

[0161] In some aspects, one or more instructions further cause the base station to send measurement data based on one or more positioning measurements to a position estimation entity.

[0162]

[0162] In some aspects, the PDCCH communications are configured to trigger a partial RACH procedure based on the configuration of the PDCCH communications.

[0163]

[0163] In some aspects, the PDCCH communications are configured to trigger a partial RACH procedure based on at least one field of the PDCCH communications.

[0164]

[0164] In some aspects, at least one field comprises a radio network temporary identifier (RNTI), or at least one field is part of downlink control information (DCI) communication, or any combination thereof.

[0165]

[0165] In some aspects, at least one field in DCI communication has a first value, a RACH transmission is configured with a first configuration based on the first value, and further comprises transmitting another DCI communication in which at least one field has a second value, the another DCI communication being configured to trigger another partial RACH procedure having another RACH transmission with a second configuration based on the second value.

[0166]

[0166] In some aspects, PDCCH communication is configured to trigger a partial RACH procedure based on the size of the PDCCH communication.

[0167]

[0167] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only receiving a RACH preamble without a RACH response to the RACH preamble.

[0168]

[0168] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises receiving a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication.

[0169]

[0169] In some aspects, the UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between transmitting and receiving.

[0170]

[0170] In some aspects, the RACH transmission is received on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the RACH transmission is received via one or more frequency layers for each of one or more respective RACH occasions, the number of one or more frequency layers being based on the number of configured frequency layers for the UE, or the RACH transmission comprises repetitions of RACH preambles over a plurality of RACH occasions, or any combination thereof.

[0171]

[0171] In some aspects, the RACH procedure may be based on a timing offset indicated via PDCCH communication.

[0172]

[0172] In some aspects, the RACH transmission is received via an authorized spectrum authorized for a particular radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by a plurality of RATs.

[0173]

[0173] In some aspects, the partial RACH procedure is the uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger the downlink part of the joint uplink and downlink positioning procedure.

[0174]

[0174] In one aspect, a non-transitory computer-readable medium storing computer-executable instructions that, when executed by a base station, cause the base station to receive, from a UE, an indication of a RACH transmission associated with a partial random access channel (RACH) procedure and to receive the RACH transmission based on the indication.

[0175]

[0175] In some aspects, the RACH transmission is for positioning and further comprises performing one or more positioning measurements on the RACH transmission.

[0176]

[0176] In some aspects, one or more instructions further cause the base station to send measurement data based on one or more positioning measurements to a positioning entity.

[0177]

[0177] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0178]

[0178] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication.

[0179]

[0179] In some aspects, the RACH transmission is received via an authorized spectrum approved for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0180]

[0180] In one aspect, a non-transitory computer-readable medium storing computer-executable instructions that, when executed by a positioning entity, cause the positioning entity to receive measurement data based on one or more positioning measurements performed by a set of base stations (BSs) on a random access channel (RACH) transmission for positioning from a user equipment (UE), and determine a positioning estimate of the UE based at least in part on the measurement data.

[0181]

[0181] In some aspects, the RACH transmission is associated with a partial RACH procedure.

[0182]

[0182] In some aspects, the partial RACH procedure is triggered by physical downlink control channel (PDCCH) communication from the UE's serving BS.

[0183]

[0183] In some aspects, the partial RACH procedure is a partial 4-step RACH procedure, where the partial RACH procedure comprises only the transmission of a RACH preamble without a RACH response to the RACH preamble.

[0184]

[0184] In some aspects, the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or the PUSCH communication.

[0185]

[0185] In some aspects, the RACH transmission for positioning is transmitted by the UE via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by multiple RATs.

[0186]

[0186] Other objects and advantages related to the aspects disclosed herein will become apparent to those skilled in the art based on the accompanying drawings and the mode for carrying out the invention.

[0187]

[0187] The accompanying drawings are presented to assist in the description of various aspects of the present disclosure and are provided for purposes of illustration of the aspects rather than limitation.

Brief Description of the Drawings

[0188]

Figure 1

[0188] A diagram showing an exemplary wireless communication system according to various aspects.

Figure 2A

[0189] A diagram showing an exemplary wireless network structure according to various aspects.

Figure 2B

Figure 3

[0190] Block diagram showing an exemplary UE in various aspects.

Figure 4A

[0191] Figure showing an exemplary frame structure and channels within the frame according to aspects of the present disclosure.

Figure 4B

Figure 4C

Figure 4D

Figure 5

[0192] Figure showing the DCI-triggered SRS-P procedure according to an aspect of the present disclosure.

Figure 6

[0193] Figure showing the 4-step physical random access channel (PRACH) procedure according to an embodiment of the present disclosure.

Figure 7

[0194] Figure showing the 2-step PRACH procedure according to an embodiment of the present disclosure.

Figure 8

[0195] Figure showing an exemplary process of wireless communication according to aspects of the present disclosure.

Figure 9

[0196] Figure showing an exemplary process of wireless communication according to aspects of the present disclosure.

Figure 10

[0197] Figure showing an exemplary process of wireless communication according to aspects of the present disclosure.

Figure 11

[0198] Figure showing an exemplary process of wireless communication according to aspects of the present disclosure.

Figure 12

[0199] Figure showing an exemplary implementation form of a process according to an aspect of the present disclosure.

Figure 13

[0200] A diagram showing an exemplary implementation of a process according to one aspect of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

[0189]

[0201] Aspects of the present disclosure are provided in the following description and the associated drawings directed to various examples provided for illustrative purposes. Alternative aspects may be devised without departing from the scope of the present disclosure. Further, well-known elements of the present disclosure are not described in detail or are omitted so as not to obscure the relevant details of the present disclosure.

[0190]

[0202] The words “exemplary” and / or “example” are used herein to mean “an example, instance, or act of exemplifying.” Any aspect described herein as “exemplary” and / or “example” should not necessarily be construed as preferred or advantageous over other aspects. Similarly, the term “aspect of the present disclosure” does not require that all aspects of the present disclosure include the described features, advantages, or mode of operation.

[0191]

[0203] Those skilled in the art will appreciate that the information and signals described below may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the following description may be represented, in part, depending on a particular application example, in part on a desired design, in part on the corresponding technology, etc., by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0192]

[0204] Furthermore, many aspects are described with respect to a series of actions to be performed, for example, by elements of a computing device. It should be recognized that the various actions described herein can be implemented by a particular circuit (e.g., an application specific integrated circuit (ASIC)), by program instructions executed by one or more processors, or by a combination of both. Further, the series of actions described herein can be considered to be implemented in their entirety within any form of non-transitory computer-readable storage medium storing a corresponding set of computer instructions that, when executed, cause the relevant processor of the device to perform or cause to be performed the functions described herein. Accordingly, the various aspects of the present disclosure can be implemented in several different forms all of which are contemplated to fall within the scope of the claimed subject matter. Further, for each of the aspects described herein, a corresponding form of any such aspect can be described herein, for example, as "logic configured to" perform the actions described.

[0193]

[0205] As used herein, the terms "user equipment" (UE) and "base station" are not intended to be specific to or otherwise limited to any particular radio access technology (RAT) unless otherwise stated. Generally, a UE can be any wireless communication device used by a user to communicate via a wireless communication network (e.g., a mobile phone, router, tablet computer, laptop computer, tracking device, wearable (e.g., smartwatch, glasses, augmented reality (AR) / virtual reality (VR) headset, etc.), vehicle (e.g., automobile, motorcycle, bicycle, etc.), Internet of Things (IoT) device, etc.). The UE can be mobile or (e.g., at some times) stationary and can communicate with a radio access network (RAN). The term "UE" as used herein may be interchangeably referred to as "access terminal" or "AT", "client device", "wireless device", "subscriber device", "subscriber terminal", "subscriber station", "user terminal" or UT, "mobile terminal", "mobile station", or variants thereof. Generally, a UE can communicate with a core network via the RAN, and through the core network, the UE can be connected to external networks such as the Internet and other UEs. Of course, other mechanisms for connecting to the core network and / or the Internet are also possible for the UE, such as via a wired access network, a wireless local area network (WLAN) network (e.g., based on IEEE802.11, etc.).

[0194]

[0206] The base station may operate according to one of several RATs with which it is communicating with the UE, depending on the network in which it is deployed, and may alternatively be referred to as an access point (AP), network node, Node B, evolved Node B (eNB), new radio (NR) Node B (also referred to as gNB or g-node B), etc. Further, in some systems, the base station may provide only a pure edge node signaling function, while in other systems, it may provide additional control and / or network management functions. The communication link through which the UE can send signals to the base station is called the uplink (UL) channel (e.g., reverse traffic channel, reverse control channel, access channel, etc.). The communication link through which the base station can send signals to the UE is called the downlink (DL) or forward link channel (e.g., paging channel, control channel, broadcast channel, forward traffic channel, etc.). The term traffic channel (TCH) as used herein may refer to either the UL / reverse traffic channel or the DL / forward traffic channel.

[0195]

[0207] The term "base station" can refer to a single physical transmission point, or multiple physical transmission points that may or may not be collocated. For example, when the term "base station" refers to a single physical transmission point, the physical transmission point can be the base station's antenna corresponding to the base station's cell. When the term "base station" refers to multiple collocated physical transmission points, the physical transmission points can be an array of antennas (such as in a multiple-input multiple-output (MIMO) system or when the base station employs beamforming). When the term "base station" refers to multiple non-collocated physical transmission points, the physical transmission points can be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transport medium) or a remote radio head (RRH) (a remote base station connected to a serving base station). Alternatively, the non-collocated physical transmission points can be the serving base station that receives measurement reports from the UE and the neighboring base station whose reference RF signal the UE is measuring.

[0196]

[0208] An "RF signal" comprises an electromagnetic wave of a given frequency that transports information through the space between a transmitter and a receiver. As used herein, a transmitter can send a single "RF signal" or multiple "RF signals" to a receiver. However, due to the propagation characteristics of the RF signal through a multipath channel, a receiver can receive multiple "RF signals" corresponding to each transmitted RF signal. The same transmitted RF signal on different paths between the transmitter and the receiver may be referred to as a "multipath" RF signal.

[0197]

[0209] In various aspects, FIG. 1 shows an exemplary wireless communication system 100 (which may also be referred to as a Wireless Wide Area Network (WWAN)). The wireless communication system 100 may include various base stations 102 and various UEs 104. The base stations 102 may include macrocell base stations (high-power cellular base stations) and / or small cell base stations (low-power cellular base stations). In one aspect, the macrocell base stations may include an eNB to which the wireless communication system 100 corresponds to an LTE network, or a gNB to which the wireless communication system 100 corresponds to a 5G network, or a combination of both, and the small cell base stations may include femtocells, picocells, microcells, and the like.

[0198]

[0210] The base stations 102 collectively form a RAN and interface with a core network 170 (e.g., an evolved packet core (EPC) or a next generation core (NGC)) through a backhaul link 122, and may interface to one or more location servers 172 through the core network 170. In addition to other functions, the base stations 102 may perform functions related to one or more of transferring user data, wireless channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection setup and release, load distribution, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and device tracing, RAN information management (RIM), paging, positioning, and delivery of warning messages. The base stations 102 may communicate with each other directly or indirectly (e.g., through the EPC / NGC) via a backhaul link 134 that may be wired or wireless.

[0199]

[0211] The base station 102 can wirelessly communicate with the UE 104. Each of the base stations 102 can provide communication coverage to its respective geographic coverage area 110. In one aspect, one or more cells can be supported by the base stations 102 in each coverage area 110. A "cell" is a logical communication entity used for communication with a base station (e.g., via some frequency resource such as a carrier frequency, component carrier, carrier, band, etc.) and can be associated with an identifier (e.g., a physical cell identifier (PCID), virtual cell identifier (VCID)) for distinguishing cells operating via the same or different carrier frequencies. In some cases, different cells can be configured according to different protocol types (e.g., machine type communication (MTC), narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or others) that can provide access to different types of UEs. In some cases, the term "cell" can also refer to the geographic coverage area (e.g., a sector) of a base station as long as a carrier frequency is detected and can be used for communication within some portion of the geographic coverage area 110.

[0200]

[0212] The geographic coverage areas 110 of neighboring macro cell base stations 102 can partially overlap (e.g., in a handover region), but some of the geographic coverage areas 110 can be significantly overlapped by a larger geographic coverage area 110. For example, a small cell base station 102' can have a coverage area 110' that significantly overlaps with the coverage areas 110 of one or more macro cell base stations 102. A network that includes both small cell base stations and macro cell base stations can be known as a heterogeneous network. A heterogeneous network can also include a home eNB (HeNB) that can provide services to a restricted group known as a closed subscriber group (CSG).

[0201]

[0213] The communication link 120 between the base station 102 and the UE 104 may include UL transmissions (also called reverse links) from the UE 104 to the base station 102 and / or downlink (DL) transmissions (also called forward links) from the base station 102 to the UE 104. The communication link 120 may use MIMO antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link 120 may be through one or more carrier frequencies. The carrier allocation may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL than for UL).

[0202]

[0214] The wireless communication system 100 may further include a WLAN access point (AP) 150 that communicates with a WLAN station (STA) 152 via a communication link 154 in an unlicensed frequency spectrum (e.g., 5 GHz). When communicating in the unlicensed frequency spectrum, the WLAN STA 152 and / or the WLAN AP 150 may perform a clear channel assessment (CCA) before communicating to determine whether the channel is available.

[0203]

[0215] The small cell base station 102’ may operate in licensed and / or unlicensed frequency spectra. When operating in the unlicensed frequency spectrum, the small cell base station 102’ may adopt LTE or 5G technology and use the same 5 GHz unlicensed frequency spectrum as used by the WLAN AP 150. The small cell base station 102’ adopting LTE / 5G in the unlicensed frequency spectrum may boost the coverage to the access network and / or increase the capacity of the access network. LTE in the unlicensed spectrum may be referred to as unlicensed LTE (LTE-U), licensed-assisted access (LAA), or MulteFire.

[0204]

[0216] The wireless communication system 100 may further include an mmW base station 180 that can operate in millimeter wave (mmW) frequencies and / or near mmW frequencies while communicating with the UE 182. Extremely high frequency (EHF) is a part of RF in the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10 millimeters. Radio waves in this band are sometimes called millimeter waves. Near mmW can extend downward to a frequency of 3 GHz with a wavelength of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, also called centimeter waves. Communication using the mmW / near mmW radio frequency band has high path loss and a relatively short range. The mmW base station 180 and the UE 182 may utilize beamforming (transmission and / or reception) via the mmW communication link 184 to compensate for the extremely high path loss and short range. Further, in an alternative configuration, it will be appreciated that one or more base stations 102 may also transmit using mmW or near mmW and beamforming. Thus, it will be appreciated that the above description is merely exemplary and should not be construed as limiting the various aspects disclosed herein.

[0205]

[0217] Transmission beamforming is a technique for focusing RF signals in a specific direction. Conventionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts the signal omnidirectionally, i.e., in all directions. In transmission beamforming, the network node determines where a given target device (e.g., a UE) is located (with respect to the transmitting network node) and projects a stronger downlink RF signal in that specific direction, thereby providing a faster and stronger RF signal (in terms of data rate) to the receiving device(s). To change the directivity of the RF signal when transmitting, the network node can control the phase and relative amplitude of the RF signal at each of one or more transmitters that are broadcasting the RF signal. For example, the network node can use an array of antennas (referred to as a "phased array" or "antenna array") that can create a beam of RF waves that can be "steered" to point in different directions without actually moving the antennas. In particular, the RF currents from the transmitters are supplied to the individual antennas with an appropriate phase relationship such that the radio waves from the separate antennas are added together to increase the radiation in the desired direction while canceling and suppressing the radiation in the undesired directions.

[0206]

[0218] The transmission beams can be quasi-collocated, which means that the transmission beams appear to have the same parameters to a receiver (e.g., UE), regardless of whether the transmission antennas of the network nodes are physically collocated or not. In NR, there are four types of quasi-collocation (QCL) relationships. In particular, a given type of QCL relationship means that some parameters regarding a second reference RF signal on a second beam can be derived from information regarding a source reference RF signal on a source beam. Thus, if the source reference RF signal is of QCL type A, the receiver can use the source reference RF signal to estimate the Doppler shift, Doppler spread, mean delay, and delay spread of the second reference RF signal transmitted on the same channel. If the source reference RF signal is of QCL type B, the receiver can use the source reference RF signal to estimate the Doppler shift and Doppler spread of the second reference RF signal transmitted on the same channel. If the source reference RF signal is of QCL type C, the receiver can use the source reference RF signal to estimate the Doppler shift and mean delay of the second reference RF signal transmitted on the same channel. If the source reference RF signal is of QCL type D, the receiver can use the source reference RF signal to estimate the spatial reception parameters of the second reference RF signal transmitted on the same channel.

[0207]

[0219] In receive beamforming, the receiver uses a receive beam to amplify the RF signals detected on a given channel. For example, the receiver can increase the gain setting of the antenna array and / or adjust the phase setting in that direction to amplify the RF signals received from a particular direction (e.g., increase its gain level). Thus, when the receiver is said to beamform in a certain direction, it means that the beam gain in that direction is high relative to the beam gains along other directions, or that the beam gain in that direction is the highest compared to the beam gains in that direction of all other receive beams available to the receiver. This results in a stronger received signal strength (e.g., reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference plus noise ratio (SINR), etc.) of the RF signals received from that direction.

[0208]

[0220] Receive beams can be spatially related. A spatial relationship means that the parameters for the transmit beam for a second reference signal can be derived from information about the receive beam for the first reference signal. For example, a UE may use a particular receive beam to receive a reference downlink reference signal (e.g., a synchronization signal block (SSB)) from a base station. The UE can then form a transmit beam for sending an uplink reference signal (e.g., a sounding reference signal (SRS)) to that base station based on the parameters of the receive beam.

[0209]

[0221] Note that the "downlink" beam can be either a transmission beam or a reception beam depending on the entity forming it. For example, when the base station forms a downlink beam to transmit a reference signal to the UE, the downlink beam is a transmission beam. However, when the UE forms a downlink beam, it is a reception beam for receiving the downlink reference signal. Similarly, the "uplink" beam can be either a transmission beam or a reception beam depending on the entity forming it. For example, when the base station forms an uplink beam, it is an uplink reception beam, and when the UE forms an uplink beam, it is an uplink transmission beam.

[0210]

[0222] In 5G, the frequency spectrum in which wireless nodes (e.g., base stations 102 / 180, UEs 104 / 182) operate is divided into multiple frequency ranges: FR1 (from 450 to 6000 MHz), FR2 (from 24250 to 52600 MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). In a multi-carrier system such as 5G, one of the carrier frequencies is called the "primary carrier" or "anchor carrier" or "primary serving cell" or "PCell", and the remaining carrier frequencies are called "secondary carriers" or "secondary serving cells" or "SCells". In carrier aggregation, the anchor carrier is the carrier that operates on the primary frequency (e.g., FR1) used by the UE 104 / 182 and the cell with which the UE 104 / 182 either performs the initial radio resource control (RRC) connection establishment procedure or starts the RRC connection re-establishment procedure. The primary carrier carries all common and UE-specific control channels. The secondary carrier can be configured when the RRC connection is established between the UE 104 and the anchor carrier and can be used to provide additional radio resources. The secondary carrier may contain only the necessary signaling information and signals. For example, since both the primary uplink carrier and the primary downlink carrier are typically UE-specific, UE-specific ones may not be present in the secondary carrier. This means that different UEs 104 / 182 in a cell can have different downlink primary carriers. The same is true for the uplink primary carrier. The network can change the primary carrier of any UE 104 / 182 at any time. This is done, for example, to distribute the load across different carriers. The terms "cell", "serving cell", "component carrier", "carrier frequency", etc. can be used interchangeably since a "serving cell" (regardless of whether it is a PCell or an SCell) corresponds to the carrier frequency / component carrier through which some base station is communicating.

[0211]

[0223] For example, still referring to FIG. 1, one of the frequencies utilized by macrocell base station 102 can be an anchor carrier (or "PCell"), and the other frequencies utilized by macrocell base station 102 and / or mmW base station 180 can be secondary carriers ("SCell"). Simultaneous transmission and / or reception of multiple carriers enables UE104 / 182 to significantly increase its data transmission and / or reception rate. For example, two aggregated 20 MHz carriers in a multi-carrier system would theoretically lead to a doubling of the data rate (i.e., 40 MHz) compared to what can be achieved by a single 20 MHz carrier.

[0212]

[0224] Wireless communication system 100 may further include one or more UEs, such as UE190, that are indirectly connected to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links. In the example of FIG. 1, UE190 has a D2D P2P link 192 with one of UEs 104 connected to one of base stations 102 (e.g., through which UE190 can indirectly obtain cellular connectivity), and a D2D P2P link 194 with WLAN STA152 connected to WLAN AP150 (through which UE190 can indirectly obtain WLAN-based Internet connectivity). In one example, D2D P2P links 192 and 194 can be supported using any well-known D2D RAT, such as LTE Direct (LTE-D), WiFi Direct (registered trademark) (WiFi(registered trademark)-D), Bluetooth(registered trademark).

[0213]

[0225] The wireless communication system 100 may further include a UE 164 that can communicate with a macrocell base station 102 via a communication link 120 and / or with a mmW base station 180 via a mmW communication link 184. For example, the macrocell base station 102 may support a PCell and one or more SCell for the UE 164, and the mmW base station 180 may support one or more SCell for the UE 164. In one aspect, the UE 164 may include a positioning component 166 that may enable the UE 164 to perform the UE operations described herein. Although only one UE of FIG. 1 is shown as having a sufficiently staggered SRS component 166, it should be noted that any of the UEs in FIG. 1 may be configured to perform the UE operations described herein.

[0214]

[0226] In various aspects, FIG. 2A shows an exemplary wireless network structure 200. For example, NGC 210 (also referred to as "5GC") can be functionally regarded as control plane functions 214 (e.g., UE registration, authentication, network access, gateway selection, etc.) and user plane functions 212 (e.g., UE gateway function, access to the data network, IP routing, etc.) that operate collaboratively to form a core network. The user plane interface (NG-U) 213 and the control plane interface (NG-C) 215 connect gNB 222 to NGC 210, particularly to the control plane function 214 and the user plane function 212. In an additional configuration, eNB 224 can also be connected to NGC 210 via NG-C 215 to the control plane function 214 and NG-U 213 to the user plane function 212. Further, eNB 224 can communicate directly with gNB 222 via a backhaul connection 223. In some configurations, the new RAN 220 can have only one or more gNB 222s, while other configurations include one or more of both eNB 224 and gNB 222. Either gNB 222 or eNB 224 can communicate with UE 204 (e.g., any of the UEs shown in FIG. 1). Another optional aspect can include a location server 230 that may be communicating with NGC 210 to provide location assistance to UE 204. The location server 230 can be implemented as a plurality of distinct servers (e.g., physically distinct servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.) or, alternatively, can correspond to each a single server. The location server 230 can be configured to support one or more location services for UE 204 that can be connected to the location server 230 via the core network, NGC 210, and / or the Internet (not shown). Further, the location server 230 can be integrated into the components of the core network or, alternatively, can be external to the core network.

[0215]

[0227] In various ways, FIG. 2B shows another exemplary wireless network structure 250. For example, NGC 260 (also referred to as “5GC”) can be considered, functionally, as a control plane function provided by access and mobility management function (AMF) / user plane function (UPF) 264 that operates collaboratively to form a core network (i.e., NGC 260), as well as a user plane function provided by session management function (SMF) 262. User plane interface 263 and control plane interface 265 connect eNB 224 to NGC 260, particularly to SMF 262 and AMF / UPF 264 respectively. In an additional configuration, gNB 222 can also be connected to NGC 260 via a control plane interface 265 to AMF / UPF 264 and a user plane interface 263 to SMF 262. Further, eNB 224 can communicate directly with gNB 222 via backhaul connection 223, with or without using gNB direct connectivity to NGC 260. In some configurations, new RAN 220 can have only one or more gNBs 222, while other configurations include one or more of both eNB 224 and gNB 222. Either gNB 222 or eNB 224 can communicate with UE 204 (e.g., any of the UEs shown in FIG. 1). The base stations of new RAN 220 communicate with the AMF side of AMF / UPF 264 via the N2 interface and with the UPF side of AMF / UPF 264 via the N3 interface.

[0216]

[0228] The functions of the AMF include registration management, connection management, reachability management, mobility management, lawful interception, transport for session management (SM) messages between the UE 204 and the SMF 266, a transparent proxy service for routing SM messages, access authentication and authorization, transport for short message service (SMS) messages between the UE 204 and a short message service function (SMSF) (not shown), and a security anchor function (SEAF). The AMF also interacts with an authentication server function (AUSF) (not shown) and receives an intermediate key established as a result of the UE 204 authentication process. In the case of authentication based on a UMTS (Universal Mobile Telecommunications System) subscriber identity module (USIM), the AMF retrieves security materials from the AUSF. The functions of the AMF also include security context management (SCM). SCM receives a key from the SEAF for use in deriving an access network specific key. The functions of the AMF also include location service management for regulatory services, transport of location service messages between the UE 204 and a location management function (LMF) 270, and between the new RAN 220 and the LMF 270, EPS bearer identifier allocation for interoperability with an evolved packet system (EPS), and UE 204 mobility event notification. Further, the AMF also supports functions for non-3GPP (registered trademark) access networks.

[0217]

[0229] The functions of the UPF include, when applicable, acting as an anchor point for in / intra-RAT mobility, acting as an external protocol data unit (PDU) session point of interconnection to a data network (not shown), providing packet routing and forwarding, packet inspection, user plane policy rule enforcement (e.g., gating, redirection, traffic steering), lawful interception (user plane collection), traffic usage reporting, quality of service (QoS) handling for the user plane (e.g., UL / DL rate enforcement, reflective QoS marking in DL), UL traffic verification (service data flow (SDF) to QoS flow mapping), transport level packet marking in UL and DL, DL packet buffering and DL data notification triggering, sending and forwarding one or more "end markers" to the source RAN node.

[0218]

[0230] The functions of the SMF262 include session management, UE Internet Protocol (IP) address allocation and management, selection and control of user plane functions, configuration of traffic steering in the UPF for routing traffic to appropriate destinations, policy enforcement and partial control of QoS, and downlink data notification. The interface through which the SMF262 communicates with the AMF side of the AMF / UPF264 is called the N11 interface.

[0219]

[0231] Another optional aspect may include an LMF 270 that may communicate with the NGC 260 to provide location assistance to the UE 204. The LMF 270 may be implemented as a plurality of distinct servers (e.g., physically distinct servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternatively, may correspond to each single server. The LMF 270 may be configured to support one or more location services for the UE 204 that can connect to the LMF 270 via a core network, via the NGC 260, and / or via the Internet (not shown).

[0220]

[0232] FIG. 3 shows some exemplary components (represented by corresponding blocks) that may be incorporated in a UE 302 (which may correspond to any of the UEs described herein), a base station 304 (which may correspond to any of the base stations described herein), and a network entity 306 (which may correspond to or implement any of the network functions described herein, including a location server 230 and an LMF 270) to support the file transfer operations taught herein. It will be appreciated that these components may be implemented in different types of devices (e.g., in an ASIC, in a system-on-chip (SoC), etc.) in different implementations. The illustrated components may also be incorporated in other devices in the communication system. For example, other devices in the system may include similar components as those described to provide similar functionality. Also, a given device may include one or more of the components. For example, a device may include multiple transceiver components that enable the device to operate on multiple carriers and / or communicate by different technologies.

[0221]

[0233] UE 302 and base station 304 each include at least one wireless communication device (represented by communication devices 308 and 314 (and, if device 304 is a relay, communication device 320)) for communicating with other nodes via at least one designated RAT. For example, communication devices 308 and 314 may communicate with each other via wireless communication link 360, which may correspond to communication link 120 of FIG. 1. Each communication device 308 includes at least one transmitter (represented by transmitter 310) for transmitting and encoding signals (e.g., messages, instructions, information, etc.) and at least one receiver (represented by receiver 312) for receiving and decoding signals (e.g., messages, instructions, information, pilots, etc.). Similarly, each communication device 314 includes at least one transmitter (represented by transmitter 316) for transmitting signals (e.g., messages, instructions, information, pilots, etc.) and at least one receiver (represented by receiver 318) for receiving signals (e.g., messages, instructions, information, etc.). If base station 304 is a relay station, each communication device 320 may include at least one transmitter (represented by transmitter 322) for transmitting signals (e.g., messages, instructions, information, pilots, etc.) and at least one receiver (represented by receiver 324) for receiving signals (e.g., messages, instructions, information, etc.).

[0222]

[0234] In some implementations, the transmitter and receiver may comprise an integrated device (e.g., implemented as the transmitter circuitry and receiver circuitry of a single communication device, commonly referred to as a "transceiver"), in some implementations, may comprise a separate transmitter device and a separate receiver device, or in other implementations, may be implemented in other ways. The wireless communication device of base station 304 (e.g., one of a plurality of wireless communication devices) may also comprise a network listening module (NLM) for performing various measurements, etc.

[0223]

[0235] The network entity 306 (and, if it is not a relay station, the base station 304) includes at least one communication device (represented by the communication device 326 and optionally 320) for communicating with other nodes. For example, the communication device 326 may comprise a network interface configured to communicate with one or more network entities via a wire-based or wireless backhaul 370 (which may correspond to the backhaul link 122 of FIG. 1). In some aspects, the communication device 326 may be implemented as a transceiver configured to support wire-based or wireless signal communication, and the transmitter 328 and the receiver 330 may be an integrated unit. This communication may involve, for example, sending and receiving messages, parameters, or other types of information. Thus, in the example of FIG. 3, the communication device 326 is shown as comprising a transmitter 328 and a receiver 330. Alternatively, the transmitter 328 and the receiver 330 may be separate devices within the communication device 326. Similarly, if the base station 304 is not a relay station, the communication device 320 may comprise a network interface configured to communicate with one or more network entities 306 via a wire-based or wireless backhaul 370. Similar to the communication device 326, the communication device 320 is shown as comprising a transmitter 322 and a receiver 324.

[0224]

[0236] The apparatuses 302, 304, and 306 also include other components that can be used with the file transmission operations disclosed herein. The UE 302 includes, for example, a processing system 332 for providing functions related to the UE operations described herein and for providing other processing functions. The base station 304 includes, for example, a processing system 334 for providing functions related to the base station operations described herein and for providing other processing functions. The network entity 306 includes, for example, a processing system 336 for providing functions related to the network functional operations described herein and for providing other processing functions. The apparatuses 302, 304, and 306 each include memory components 338, 340, and 342 (for example, each including a memory device) to maintain information (such as information indicating reserved resources, thresholds, parameters, etc.). Further, the UE 302 includes a user interface 350 that provides means for providing an indication to the user (such as an audible and / or visual indication) and / or means for receiving user input (such as when a user operates a sensing device such as a keypad, touch screen, microphone, etc.). Although not shown, the apparatuses 304 and 306 may also include a user interface.

[0225]

[0237] Looking at the processing system 334 in more detail, in the downlink, IP packets from the network entity 306 can be provided to the processing system 334. The processing system 334 may implement functions for the radio resource control (RRC) layer, the packet data convergence protocol (PDCP) layer, the radio link control (RLC) layer, and the media access control (MAC) layer. The processing system 334 is responsible for RRC layer functions related to the broadcasting of system information (e.g., master information block (MIB), system information block (SIB)), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-RAT mobility, measurement configuration for UE measurement reports, header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; PDCP layer functions related to header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functions related to the transfer of upper layer packet data units (PDUs), error correction via ARQ, concatenation, segmentation, and reassembly of RLC service data units (SDUs), resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions related to the mapping between logical channels and transport channels, scheduling information reporting, error correction, priority handling, and logical channel prioritization.

[0226]

[0238] The transmitter 316 and the receiver 318 may implement layer 1 functions related to various signal processing functions. Layer 1, including the physical (PHY) layer, may include error detection on the transport channel, forward error correction (FEC) coding / decoding of the transport channel, interleaving, rate matching, mapping onto the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. The transmitter 316 handles mapping to signal constellations based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase shift keying (M-PSK), multi-value quadrature amplitude modulation (M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream is then mapped to orthogonal frequency division multiplexing (OFDM) subcarriers to generate a physical channel carrying a time-domain OFDM symbol stream, multiplexed with a reference signal (e.g., a pilot) in the time and / or frequency domain, and then synthesized with each other using an inverse fast Fourier transform (IFFT). The OFDM stream is spatially precoded to generate a plurality of spatial streams. The channel estimate values from the channel estimator may be used to determine the coding and modulation schemes, as well as for spatial processing. The channel estimate values may be derived from the reference signals transmitted by the UE 302 and / or channel state feedback. Each spatial stream may then be provided to one or more different antennas. The transmitter 316 may modulate an RF carrier with each spatial stream for transmission.

[0227]

[0239] At UE 302, receiver 312 receives signals through its respective antenna(s). Receiver 312 recovers the information modulated on the RF carrier and provides the information to processing system 332. Transmitter 310 and receiver 312 implement layer 1 functions related to various signal processing functions. Receiver 312 may perform spatial processing on the information to recover the spatial stream destined for UE 302. If multiple spatial streams are destined for UE 302, they may be combined by receiver 312 into a single OFDM symbol stream. Receiver 312 then uses a fast Fourier transform (FFT) to convert the OFDM symbol stream from the time domain to the frequency domain. The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier and the reference signals are recovered and demodulated by determining the most likely signal constellation points transmitted by base station 304. These soft decisions may be based on the channel estimates calculated by the channel estimator. The soft decisions are then decoded and deinterleaved to recover the data and control signals originally transmitted by base station 304 on the physical channel. The data and control signals are then provided to processing system 332 which implements layer 3 and layer 2 functions.

[0228]

[0240] In the UL, processing system 332 provides demultiplexing in reverse between the transport channel and the logical channel, packet reassembly, decoding, header recovery, and control signal processing to recover IP packets from the core network. Processing system 332 is also responsible for error detection.

[0229]

[0241] Similar to the functions described for DL transmission by the base station 304, the processing system 332 provides RRC layer functions related to system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting, PDCP layer functions related to header compression / decompression and security (encryption, decryption, integrity protection, integrity verification), transfer of upper layer PDUs, error correction via ARQ, concatenation, segmentation, and reassembly of RLC SDUs, resegmentation of RLC data PDUs, rearrangement of RLC data PDUs, RLC layer functions related to mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via HARQ, priority handling, and logical channel prioritization.

[0230]

[0242] Channel estimates derived by the channel estimator from reference signals or feedback transmitted by the base station 304 can be used by the transmitter 310 to select an appropriate coding and modulation scheme and to enable spatial processing. The spatial streams generated by the transmitter 310 can be provided to (one or more) different antennas. The transmitter 310 can modulate the RF carriers with each spatial stream for transmission.

[0231]

[0243] UL transmission is processed at the base station 304 in a manner similar to the manner described for the receiver function in the UE 302. The receiver 318 receives signals through its respective (one or more) antennas. The receiver 318 recovers the information modulated on the RF carriers and provides that information to the processing system 334.

[0232]

[0244] In the UL, the processing system 334 provides demultiplexing between the transport channel and the logical channel, packet reassembly, decoding, header restoration, and control signal processing to restore IP packets from the UE 302. The IP packets from the processing system 334 can be provided to the core network. The processing system 334 is also responsible for error detection.

[0233]

[0245] In one aspect, the apparatuses 302, 304, and 306 may each include RACH components 344, 348, and positioning components 349, respectively. It will be appreciated that the functions of the various components 344, 348, and 349 may vary based on the device in which they are implemented. The RACH components 344, 348, and the positioning components 349 may each be part of or coupled to the processing systems 332, 334, and 336 that cause the apparatuses 302, 304, and 306 to perform the functions described herein when executed, or may be hardware circuits. Alternatively, the RACH components 344, 348, and the positioning components 349 may each be memory modules stored in the memory components 338, 340, and 342 that cause the apparatuses 302, 304, and 306 to perform the functions described herein when executed by the processing systems 332, 334, and 336.

[0234]

[0246] For convenience, the apparatuses 302, 304, and / or 306 are shown in FIG. 3 as including various components that may be configured according to the various examples described herein. However, it will be appreciated that the illustrated blocks may have different functions in different designs.

[0235]

[0247] The various components of apparatuses 302, 304, and 306 can communicate with each other via data buses 352, 354, and 356, respectively. The components in FIG. 3 can be implemented in various ways. In some implementations, the components in FIG. 3 can be implemented in one or more circuits, such as, for example, one or more processors and / or one or more ASICs (which may include one or more processors). Here, each circuit uses at least one memory component for storing information or executable code used by the circuit to provide this functionality and / or can incorporate it. For example, some or all of the functions represented by blocks 308, 332, 338, 334, and 350 can be implemented by the processor of UE 302 and (one or more) memory components (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). Similarly, some or all of the functions represented by blocks 314, 320, 334, 340, and 348 can be implemented by the processor of base station 304 and (one or more) memory components (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). Also, some or all of the functions represented by blocks 326, 336, 342, and 349 can be implemented by the processor of network entity 306 and (one or more) memory components (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). For simplicity, various operations, actions, and / or functions are described herein as being performed "by the UE", "by the base station", "by the positioning entity", etc. However, as will be appreciated, such operations, actions, and / or functions are actually performed by specific components or combinations of components of the UE, base station, positioning entity, etc., such as processing systems 332, 334, 336, communication devices 308, 314, 326, RACH components 344, 348, and positioning components 349.

[0236]

[0248] To support downlink and uplink transmissions between network nodes (e.g., base stations and UEs), various frame structures can be used. FIG. 4A is a diagram 400 showing an example of a downlink frame structure according to an aspect of the present disclosure. FIG. 4B is a diagram 430 showing an example of channels within the downlink frame structure according to an aspect of the present disclosure. FIG. 4C is a diagram 450 showing an example of an uplink frame structure according to an aspect of the present disclosure. FIG. 4D is a diagram 480 showing an example of channels within the uplink frame structure according to an aspect of the present disclosure. Other wireless communication technologies may have different frame structures and / or different channels.

[0237]

[0249] LTE, and in some cases NR, utilize OFDM on the downlink and single-carrier frequency-division multiplexing (SC-FDM) on the uplink. However, unlike LTE, NR has an option to use OFDM on the uplink as well. OFDM and SC-FDM divide the system bandwidth into a plurality (K) of orthogonal subcarriers, also commonly referred to as tones, bins, etc. Each subcarrier can be modulated with data. Generally, modulation symbols are sent in the frequency domain in OFDM and in the time domain in SC-FDM. The spacing between adjacent subcarriers can be fixed, and the total number (K) of subcarriers can depend on the system bandwidth. For example, the subcarrier spacing can be 15 kilohertz (kHz), and the minimum resource allocation (resource block) can be 12 subcarriers (or 180 kHz). Thus, the nominal FFT size can be equal to 128, 256, 512, 1024, or 2048 for system bandwidths of 1.25, 2.5, 5, 10, or 20 megahertz (MHz), respectively. The system bandwidth can also be divided into subbands. For example, a subband can cover 1.08 MHz (i.e., 6 resource blocks), and there can be 1, 2, 4, 8, or 16 subbands for system bandwidths of 1.25, 2.5, 5, 10, or 20 MHz, respectively.

[0238]

[0250] LTE supports a single numerology (such as subcarrier spacing (SCS), symbol length, etc.). In contrast, NR can support multiple numerologies (μ), for example, subcarrier spacings of 15 kHz (μ = 0), 30 kHz (μ = 1), 60 kHz (μ = 2), 120 kHz (μ = 3), and 240 kHz (μ = 4), or larger ones may be available. At each subcarrier spacing, there are 14 symbols per slot. For 15 kHz SCS (μ = 0), there is 1 slot per subframe and 10 slots per frame, the slot duration is 1 millisecond (ms), the symbol duration is 66.7 microseconds (μs), and the maximum nominal system bandwidth in MHz with a 4K FFT size is 50. For 30 kHz SCS (μ = 1), there are 2 slots per subframe and 20 slots per frame, the slot duration is 0.5 ms, the symbol duration is 33.3 μs, and the maximum nominal system bandwidth in MHz with a 4K FFT size is 100. For 60 kHz SCS (μ = 2), there are 4 slots per subframe and 40 slots per frame, the slot duration is 0.25 ms, the symbol duration is 16.7 μs, and the maximum nominal system bandwidth in MHz with a 4K FFT size is 200. For 120 kHz SCS (μ = 3), there are 8 slots per subframe and 80 slots per frame, the slot duration is 0.125 ms, the symbol duration is 8.33 μs, and the maximum nominal system bandwidth in MHz with a 4K FFT size is 400. For 240 kHz SCS (μ = 4), there are 16 slots per subframe and 160 slots per frame, the slot duration is 0.0625 ms, the symbol duration is 4.17 μs, and the maximum nominal system bandwidth in MHz with a 4K FFT size is 800.

[0239]

[0251] In the examples of FIGS. 4A to 4D, a numerology of 15 kHz is used. Therefore, in the time domain, a 10 ms frame is divided into 10 equal-sized sub-frames of 1 ms each, and each sub-frame contains one time slot. In FIGS. 4A to 4D, time is represented horizontally (on the X-axis), time increases from left to right, frequency is represented vertically (on the Y-axis), and frequency increases (or decreases) from bottom to top.

[0240]

[0252] A resource grid can be used to represent time slots, and each time slot contains one or more time-parallel resource blocks (RBs) (also called physical RBs (PRBs)) in the frequency domain. The resource grid is further divided into a plurality of resource elements (REs). An RE can correspond to one symbol length in the time domain and one sub-carrier in the frequency domain. In the numerology of FIGS. 4A to 4D, for the normal cyclic prefix, an RB may contain 12 consecutive sub-carriers in the frequency domain for a total of 84 REs and may contain 7 consecutive symbols in the time domain. For the extended cyclic prefix, an RB may contain 12 consecutive sub-carriers in the frequency domain for a total of 72 REs and may contain 6 consecutive symbols in the time domain. The number of bits carried by each RE depends on the modulation scheme.

[0241]

[0253] Some of the REs carry downlink reference (pilot) signals (DL-RS). The DL-RS can include PRS, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, etc. FIG. 4A shows an exemplary location of the REs that carry the PRS (labeled "R").

[0242]

[0254] The set of resource elements (REs) used for the transmission of PRS is referred to as a "PRS resource". The set of resource elements can span multiple PRBs in the frequency domain and can span (one or more, etc.) "N" consecutive symbols within a slot in the time domain. In a given OFDM symbol in the time domain, the PRS resource occupies consecutive PRBs in the frequency domain.

[0243]

[0255] The transmission of the PRS resource within a given PRB has a specific comb size (also referred to as the "comb density"). The comb size "N" represents the subcarrier spacing (or frequency / tone spacing) within each symbol of the PRS resource configuration. Specifically, in the case of comb size "N", the PRS is transmitted in every Nth subcarrier of the symbol of the PRB. For example, in the case of comb 4, for each symbol of the PRS resource configuration, the REs corresponding to every fourth subcarrier (such as subcarriers 0, 4, 8, etc.) are used to transmit the PRS of the PRS resource. Currently, comb sizes of comb 2, comb 4, comb 6, and comb 12 are supported for DL-PRS. FIG. 4A shows an exemplary PRS resource configuration for comb 6 (spanning 6 symbols). That is, the location of the shaded REs (labeled "R") indicates the comb 6 PRS resource configuration.

[0244]

[0256] Currently, the DL-PRS resource can span 2, 4, 6, or 12 consecutive symbols within a slot with a fully frequency-domain staggered pattern. The DL-PRS resource can be configured in any upper-layer configured downlink or flexible (FL) symbol of the slot. There can be a constant resource element unit energy (EPRE) for all REs of a given DL-PRS resource. The following are the frequency offsets between symbols for comb sizes 2, 4, 6, and 12 spanning 2, 4, 6, and 12 symbols. Comb 2 of 2 symbols: {0,1}, Comb 2 of 4 symbols: {0,1,0,1}, Comb 2 of 6 symbols: {0,1,0,1,0,1}, Comb 2 of 12 symbols: {0,1,0,1,0,1,0,1,0,1,0,1}, Comb 4 of 4 symbols: {0,2,1,3}, Comb 4 of 12 symbols: {0,2,1,3,0,2,1,3,0,2,1,3}, Comb 6 of 6 symbols: {0,3,1,4,2,5}, Comb 6 of 12 symbols: {0,3,1,4,2,5,0,3,1,4,2,5}, and Comb 12 of 12 symbols: {0,6,3,9,1,7,4,10,2,8,5,11}.

[0245]

[0257] A "PRS resource set" is a set of PRS resources used for the transmission of PRS signals, where each PRS resource has a PRS resource ID. Further, the PRS resources in a PRS resource set are associated with the same TRP. A PRS resource set is identified by a PRS resource set ID and is associated with a specific TRP (identified by the TRP ID). Further, the PRS resources in a PRS resource set have the same periodicity, the same common muting pattern configuration, and the same repetition factor (such as "PRS-ResourceRepetitionFactor") across slots. The periodicity is the time from the first repetition of the first PRS resource of the first PRS instance to the first repetition of the same first PRS resource of the next PRS instance. The periodicity can have a length selected from 2^μ*{4,5,8,10,16,20,32,40,64,80,160,320,640,1280,2560,5120,10240} slots, where μ = 0, 1, 2, 3. The repetition factor can have a length selected from {1,2,4,6,8,16,32} slots.

[0246]

[0258] The PRS resource ID in a PRS resource set is associated with a single beam (or beam ID) transmitted from a single TRP (where the TRP can transmit one or more beams). That is, each PRS resource of a PRS resource set can be transmitted on a different beam, and thus, a "PRS resource" or simply a "resource" may be referred to as a "beam". It should be noted that this has no implication regarding whether the TRP and the beam on which the PRS is transmitted are known to the UE.

[0247]

[0259] A "PRS instance" or "PRS occasion" is one instance of a periodically repeating time window (such as a group of one or more consecutive slots) in which a PRS is expected to be transmitted. A PRS occasion may also be referred to as a "PRS positioning occasion", "PRS positioning instance", "positioning occasion", "positioning instance", "positioning repetition", or simply "occasion", "instance", or "repetition".

[0248]

[0260] A "positioning frequency layer" (also simply referred to as "frequency layer") is a set of one or more PRS resource sets across one or more TRPs having the same value for several parameters. Specifically, the set of PRS resource sets has the same subcarrier spacing and cyclic prefix (CP) type (meaning that all numerologies supported for PDSCH are also supported for PRS), the same point A, the same value of the downlink PRS bandwidth, the same starting PRB (and center frequency), and the same comb size. The point A parameter takes the value of the parameter "ARFCN-ValueNR" (where "ARFCN" represents "absolute radio frequency channel number") and is an identifier / code that specifies a pair of physical radio channels used for transmission and reception. The downlink PRS bandwidth may have a granularity of 4 PRBs, is at least 24 PRBs, and at most 272 PRBs. Currently, up to 4 frequency layers are defined, and up to 2 PRS resource sets can be configured per TRP per frequency layer.

[0249]

[0261] The concept of frequency layer is somewhat similar to the concepts of component carrier and bandwidth part (BWP), but different in that component carriers and BWPs are used by one base station (or macro cell base station and small cell base station) to transmit data channels, while frequency layers are used by several (usually three or more) base stations to transmit PRS. The UE may indicate the number of frequency layers it can support when sending its positioning capabilities to the network, such as during an LTE positioning protocol (LPP) session. For example, the UE may indicate whether it can support one or four positioning frequency layers.

[0250]

[0262] Figure 4B shows an example of various channels within the downlink slot of a radio frame. In NR, the channel bandwidth or system bandwidth is divided into multiple BWPs. A BWP is a contiguous set of PRBs selected from a contiguous subset of common RBs for a given numerology on a given carrier. Generally, up to four BWPs can be specified for both downlink and uplink. That is, the UE may consist of up to four BWPs on the downlink and up to four BWPs on the uplink. At a given time, only one BWP (either uplink or downlink) can be active, which means that the UE can only receive or transmit on one BWP at a time. On the downlink, the bandwidth of each BWP should be equal to or larger than the bandwidth of the SSB, which may or may not include the SSB.

[0251]

[0263] Referring to FIG. 4B, the primary synchronization signal (PSS) is used by the UE to determine subframe / symbol timing and physical layer identification information. The secondary synchronization signal (SSS) is used by the UE to determine the physical layer cell identification information group number and radio frame timing. Based on the physical layer identification information and the physical layer cell identification information group number, the UE can determine the PCI. Based on the PCI, the UE can determine the location of the above-mentioned DL-RS. The physical broadcast channel (PBCH) carrying the MIB can be logically grouped using the PSS and SSS to form an SSB (also called SS / PBCH). The MIB provides the number of RBs in the downlink system bandwidth and the system frame number (SFN). The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH such as the system information block (SIB), and paging messages.

[0252]

[0264] The physical downlink control channel (PDCCH) carries downlink control information (DCI) within one or more control channel elements (CCE), each CCE containing one or more resource element group (REG) bundles (which can span multiple symbols in the time domain), each REG bundle containing one or more REGs, and each REG corresponding to 12 resource elements (one resource block) in the frequency domain and one OFDM symbol in the time domain. The set of physical resources used to carry the PDCCH / DCI is called a control resource set (CORESET) in NR. In NR, the PDCCH is limited to a single CORESET and is transmitted together with its own DMRS. This enables UE-specific beamforming for the PDCCH.

[0253]

[0265] In the example of FIG. 4B, there is one CORESET for each BWP, and the CORESET spans three symbols in the time domain (however, it can be only one or two symbols). Different from the LTE control channel that occupies the entire system bandwidth, in NR, the PDCCH channel is localized in a specific region in the frequency domain (i.e., CORESET). Therefore, the frequency components of the PDCCH shown in FIG. 4B are shown as smaller than a single BWP in the frequency domain. Note that the illustrated CORESET is continuous in the frequency domain, but it does not have to be continuous. Furthermore, the CORESET can span less than three symbols in the time domain.

[0254]

[0266] The DCI in the PDCCH carries information regarding uplink resource allocation (persistent and non-persistent) and a description of the downlink data transmitted to the UE, called uplink grant and downlink grant, respectively. More specifically, the DCI indicates the resources scheduled for the downlink data channel (e.g., PDSCH) and the uplink data channel (e.g., PUSCH). Multiple (e.g., up to eight) DCIs can be configured in the PDCCH, and these DCIs can have one of multiple formats. For example, there are different DCI formats for uplink scheduling, for downlink scheduling, for uplink transmission power control (TPC), etc. The PDCCH can be transported by one, two, four, eight, or sixteen CCEs to adapt to different DCI payload sizes or coding rates.

[0255]

[0267] As shown in FIG. 4C, some of the REs (labeled "R") carry DMRS for channel estimation at a receiver (e.g., a base station, another UE, etc.). The UE may further transmit SRS, for example, in the last symbol of a slot. The SRS may have a comb structure, and the UE may transmit the SRS on one of the combs. In the example of FIG. 4C, the illustrated SRS is comb 2 over one symbol. The SRS may be used by the base station to obtain channel state information (CSI) for each UE. The CSI describes how an RF signal propagates from the UE to the base station and represents the combined effects of scattering, fading, and power attenuation due to distance. The system uses the SRS for resource scheduling, link adaptation, massive MIMO, beam management, etc.

[0256]

[0268] Currently, the SRS resources can span one, two, four, eight, or twelve consecutive symbols within a slot having a comb size of comb 2, comb 4, or comb 8. The following are the frequency offsets between symbols for the currently supported SRS comb patterns. One-symbol comb 2: {0}, two-symbol comb 2: {0,1}, four-symbol comb 2: {0,1,0,1}, four-symbol comb 4: {0,2,1,3}, eight-symbol comb 4: {0,2,1,3,0,2,1,3}, twelve-symbol comb 4: {0,2,1,3,0,2,1,3,0,2,1,3}, four-symbol comb 8: {0,4,2,6}, eight-symbol comb 8: {0,4,2,6,1,5,3,7}, and twelve-symbol comb 8: {0,4,2,6,1,5,3,7,0,4,2,6}.

[0257]

[0269] The set of resource elements used for the transmission of SRS is called an "SRS resource" and can be identified by the parameter "SRS-ResourceId". The set of resource elements can span multiple PRBs in the frequency domain and can span N (e.g., one or more) consecutive symbols within a slot in the time domain. In a given OFDM symbol, the SRS resource occupies consecutive PRBs. An "SRS resource set" is a set of SRS resources used for the transmission of SRS signals and is identified by an SRS resource set ID ("SRS-ResourceSetId").

[0258]

[0270] Generally, a UE transmits SRS to enable a receiving base station (either a serving base station or a neighboring base station) to measure the channel quality between the UE and the base station. However, SRS can also be specifically configured as an uplink positioning reference signal for uplink-based positioning procedures such as uplink time difference of arrival (UL-TDOA), round trip time (RTT), uplink angle of arrival (UL-AoA). The term "SRS" as used herein can refer to SRS configured for channel quality measurement or SRS configured for positioning purposes. When it is necessary to distinguish between those two types of SRS, the former may be referred to herein as "SRS-for-communication" and / or the latter as "SRS-for-positioning".

[0259]

[0271] Several enhancements over previous definitions of SRS are proposed for positioning SRS (also referred to as "UL-PRS"), such as a new staggered pattern within the SRS resource (excluding single-symbol / COM2), a new COM type for SRS, a new sequence for SRS, a higher number of SRS resource sets per component carrier, and a higher number of SRS resources per component carrier. Further, the parameters "SpatialRelationInfo" and "PathLossReference" should be configured based on the downlink reference signal or SSB from the neighboring TRP. Additionally, one SRS resource can be transmitted outside the active BWP, and one SRS resource can span across multiple component carriers. Also, SRS is configured in the RRC connected state and can be transmitted only within the active BWP. Further, there can be frequency hopping, no repetition factor, a single antenna port, and new lengths for SRS (e.g., 8 and 12 symbols). Also, there can be open-loop power control and no closed-loop power control, and COM8 (i.e., SRS transmitted in every 8th subcarrier within the same symbol) can be used. Finally, the UE can transmit through the same transmit beam from multiple SRS resources for UL-AoA. All of these are features added to the current SRS framework, and they are configured through RRC upper layer signaling (and potentially triggered or activated through MAC control element (CE) or DCI).

[0260]

[0272] FIG. 4D shows an example of various channels within an uplink slot of a frame according to an aspect of the present disclosure. A random access channel (RACH), also referred to as a physical random access channel (PRACH), can be within one or more slots in a frame based on a PRACH configuration. The PRACH can include six consecutive RB pairs within a slot. The PRACH enables a UE to perform an initial system access and achieve uplink synchronization. A physical uplink control channel (PUCCH) can be located on the edge of the uplink system bandwidth. The PUCCH carries uplink control information (UCI) such as scheduling requests, CSI reports, channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI), and HARQ ACK / NACK feedback. A physical uplink shared channel (PUSCH) carries data and can be further used to carry a buffer status report (BSR), a power headroom report (PHR), and / or UCI.

[0261]

[0273] Note that the terms "positioning reference signal" and "PRS" generally refer to the specific reference signals used for positioning in NR and LTE systems. However, the terms "positioning reference signal" and "PRS" as used herein may refer to any type of reference signal that can be used for positioning, including but not limited to PRS, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, SRS, UL-PRS, etc., defined in LTE and NR. Further, the terms "positioning reference signal" and "PRS" may refer to downlink or uplink positioning reference signals, unless otherwise specified by the context. When it is necessary to further distinguish the types of PRS, the downlink positioning reference signal may be referred to as "DL-PRS", and the uplink positioning reference signal (e.g., SRS for positioning, PTRS) may be referred to as "UL-PRS". Further, in the case of signals that can be transmitted in both uplink and downlink (e.g., DMRS, PTRS), those signals may be prefixed with "UL" or "DL" to distinguish the direction. For example, "UL-DMRS" can be distinguished from "DL-DMRS".

[0262]

[0274] SRS is an uplink dedicated signal transmitted by a UE to assist the base station in obtaining the channel state information (CSI) of each user. The channel state information describes how the RF signal propagates from the UE to the base station and represents the combined effects of scattering, fading, and power attenuation due to distance. The system uses SRS for resource scheduling, link adaptation, massive MIMO, beam management, etc.

[0263]

[0275] Several extensions to the previous definition of SRS, such as new stagger patterns within the SRS resource, new comb types for SRS, new sequences for SRS, higher numbers of SRS resource sets per component carrier, and higher numbers of SRS resources per component carrier, have been proposed for the positioning SRS (SRS-P). Further, the parameters "SpatialRelationInfo" and "PathLossReference" are to be configured based on the DL RS from neighboring TRPs. Furthermore, one SRS resource can be transmitted outside the active bandwidth part (BWP), and one SRS resource can span multiple component carriers. Finally, the UE can transmit through the same transmission beam from multiple SRS resources for UL-AoA. All of these are features added to the current SRS framework, and they are configured through RRC upper layer signaling (and potentially triggered or activated through MAC control elements (CE) or downlink control information (DCI)).

[0264]

[0276] As described above, the sounding reference signal (SRS) in NR is a UE-specific configured reference signal transmitted by the UE for the purpose of sounding the uplink radio channel. Similar to CSI-RS, such sounding provides various levels of knowledge about the radio channel characteristics. At one extreme, the SRS can be used at the gNB, for example, for UL beam management purposes, simply to obtain signal strength measurements. At the other extreme, the SRS can be used at the gNB to obtain detailed amplitude and phase estimates as a function of frequency, time, and space. In NR, channel sounding using SRS supports a more diverse set of use cases compared to LTE (e.g., downlink CSI collection (downlink MIMO) for reciprocity-based gNB transmission beamforming, uplink CSI collection for link adaptation, and codebook / non-codebook-based precoding for uplink MIMO, uplink beam management, etc.).

[0265]

[0277] The SRS can be configured using various options. The time / frequency mapping of the SRS resource is defined by the following characteristics.

[0266] · Duration N symb SRS - Different from LTE which allows only a single OFDM symbol per slot for the SRS resource duration, it can be 1, 2, or 4 consecutive OFDM symbols within a slot.

[0267] · Starting symbol location l0 - The starting symbol of the SRS resource can be located anywhere within the last 6 OFDM symbols of the slot, provided that the resource does not cross the slot end boundary.

[0268] · Repetition factor R - In an SRS resource configured with frequency hopping, the repetition enables the same set of sub - carriers to be sounded in R consecutive OFDM symbols before the next hop occurs (when used herein, "hop" specifically refers to a frequency hop). For example, the value of R is 1, 2, 4, where R ≤ N symb SRS 。

[0269] · Transmission comb interval K TC and comb offset k TC - The SRS resource can occupy resource elements (REs) of a frequency - domain comb structure, where the comb interval is 2 or 4 REs as in LTE. Such a structure enables frequency - domain multiplexing of different SRS resources of the same or different users on different combs, where different combs are offset from each other by an integer number of REs. The comb offset is defined with respect to the PRB boundary and can take values in the range 0, 1, …, K TC - 1 within an RE. Thus, for a comb interval K TC = 2, there are 2 different available combs for multiplexing if needed, and for a comb interval K TC = 4, there are 4 different available combs.

[0270] · Periodicity and slot offset in the case of periodic / semi-persistent SRS.

[0271] · Sounding bandwidth within the bandwidth part.

[0272]

[0278] For low-latency positioning, the gNB may trigger UL SRS-P via DCI (e.g., the transmitted SRS-P may include repetitions or beam sweeps to enable some gNBs to receive the SRS-P). Alternatively, the gNB may send information regarding aperiodic PRS transmission to the UE (e.g., this configuration may include information regarding PRS from multiple gNBs to enable the UE to perform positioning (UE-based) or reporting (UE-assisted) timing calculations).

[0273]

[0279] FIG. 5 shows a DCI-triggered SRS-P procedure 500 according to one aspect of the present disclosure. At 502, an active SRS configuration is established between the serving BS 304 and the UE 302. At 504, the serving BS 304 utilizes the active SRS configuration established at 502 to transmit a DCI comprising a PDCCH configured to trigger SRS-P. At 506, the UE 302 transmits SRS-P in response to the PDCCH. The serving BS 304 and one or more non-serving BSs 304 each measure the SRS-P at 508-510.

[0274]

[0280] In some scenarios, it may be possible for a UE not to have an active SRS configuration that can be utilized by a gNB to immediately trigger SRS transmission. Embodiments of the present disclosure may thereby be part of a partial RACH procedure that corresponds to a limited or shortened version of the "normal" random access channel (RACH) procedure in some designs, targeting RACH transmissions for positioning (e.g., RACH preamble transmissions). Such embodiments may provide various technical advantages, such as obtaining a rough positioning estimate of the UE with lower latency (e.g., especially in scenarios where an active SRS configuration is not set up for the UE). Below, the complete RACH (or PRACH) procedure is described with respect to FIGS. 6-7, and then the discussion of the partial RACH procedure according to various aspects of the present disclosure follows.

[0275]

[0281] FIG. 6 shows a four-step physical random access channel (PRACH) procedure 600 according to an embodiment of the present disclosure. The four-step PRACH procedure 600 is an initial access procedure by which a UE (e.g., UE 302) can initiate communication with a BS (e.g., BS 304).

[0276]

[0282] Referring to FIG. 6, at 602, a message 1 ("Msg-1") of the four-step PRACH procedure 600 is transmitted by UE 302 to BS 304. The Msg-1 at 602 may be characterized herein as a PRACH preamble (or more generally as a RACH preamble). In one example, the Msg-1 at 602 may indicate the presence of a random access attempt and may be implemented as a Zadoff-Chu sequence that enables BS 304 to perform channel estimation between BS 304 and UE 302.

[0277]

[0283] Referring to FIG. 6, at 604, a message 2 (“Msg-2”) of the 4-step PRACH procedure 600 is transmitted by the BS 304 to the UE 302. The Msg-2 at 604 may be characterized as a random access response (RAR) herein. For example, in response to the detected PRACH preamble (or Msg-1) at 602, the BS 304 may transmit the Msg-2 at 604 on the downlink (DL) shared channel (SCH) with any of the following combinations.

[0278] · The index of the detected PRACH preamble (or Msg-1) from 602, · Uplink timing correction for the UE 302, · A scheduling grant indicating what resources the UE 302 should use for transmitting a message 3 (“Msg-3”) of the 4-step PRACH procedure 600, and · A temporary cell radio network temporary identifier (TC-RNTI) used for further communication between the UE 302 and the BS 304

[0284] In one example, the Msg-2 at 604 is scheduled on the SL SCH and may be indicated on the physical downlink control channel (PDCCH) using identification information (e.g., a random access RNTI (RA-RNTI)) indicated by the time and frequency resources on which the PRACH preamble (or Msg-1) from 602 is transmitted.

[0279]

[0285] Referring to FIG. 6, at 606, a message 3 ("Msg-3") comprising at least the UE identifier (ID) of UE 302 is transmitted by UE 302 to BS 304. In some designs, Msg-3 is transmitted via the physical uplink shared channel (PUSCH) and may be referred to as Msg-3 PUSCH. In one example, the Msg-3 transmitted at 606 may be transmitted via the UL SCH resources indicated by Msg-2 from 604. In some designs, device scrambling is used for the transmission of Msg-3 at 606 (e.g., scrambling based on the TC-RNTI allocated via Msg-2 from 604). In some designs, if UE 302 is in a radio resource control (RRC) connection state with the C-RNTI already allocated to it, the C-RNTI may be used as the UE-ID in Msg-3 at 606. In some designs, if UE 302 is not in the RRC-connection state, a core network device identifier such as a 40-bit serving temporary mobile subscriber identity (S-TMSI) may be used as the UE-ID in Msg-3 at 606.

[0280]

[0286] Referring to FIG. 6, at 608, another Msg-3 is, in some cases, transmitted as a hybrid automatic repeat request (HARQ) acknowledgement (ACK) for Msg-2 from 604. In some designs, Msg-3 is transmitted via the PUCCH and may be referred to as Msg-3 PUCCH. In some designs, whether Msg-3 PUCCH is transmitted at 608 or not may be configured via RRC signaling or via one or more information elements (IEs) in the system information block (SIB).

[0281]

[0287] Referring to FIG. 6, at 610, a message 4 ( "Msg-4") of the 4-step PRACH procedure 600 is transmitted by the BS 304 to the UE 302. In some designs, the Msg-4 at 608 includes a downlink message for contention resolution when there is some probability of contention related to the Msg-3 transmission at 606-608. For example, if multiple UEs transmit the same Msg-1 (602) simultaneously, the multiple UEs may respond to the same Msg-2 (604) such that a collision occurs. In some designs, if the UE 302 has already been assigned a C-RNTI, contention resolution can be handled by addressing the UE 302 on the PDCCH using the C-RNTI. In some designs, if the UE 302 does not have a valid C-RNTI (e.g., the UE 302 is in RRC idle prior to 602), Msg-4 contention resolution can be handled by addressing the UE 302 on the PDCCH using the TC-RNTI, and the UE 302 compares the UE-ID received within the PDSCH scheduled by the PDCCH of the Msg-4 with the UE-ID transmitted in the Msg-3 PUSCH at 606, and if a match is observed, determines that the 4-step PRACH procedure 600 is successful, and thereafter, the C-RNTI is confirmed as the C-RNTI. At 612, the UE 302 and the BS 304 may exchange user data, if applicable.

[0282]

[0288] FIG. 7 shows a 2-step PRACH procedure 700 according to an embodiment of the present disclosure. Similar to the 4-step PRACH procedure 600, the 2-step PRACH procedure 700 is an initial access procedure by which a UE (e.g., UE 302) can initiate communication with a BS (e.g., BS 304). However, in the 2-step PRACH procedure 700, the Msg-1 and Msg-3 (PUSCH) are transmitted to the BS 304 before any response from the BS 304 is transmitted as "Msg-A" and the BS 304 sends back a "Msg-B" (e.g., including Msg-2 and Msg-4) to the UE 302.

[0283]

[0289] Referring to FIG. 7, at 702, UE 302 transmits Msg-A (e.g., PRACH preamble and related UE ID information or PUSCH as in Msg-1 and Msg-3) to BS 304. At 704, BS 304 transmits Msg-B (e.g., RAR together with contention resolution as in Msg-2 and Msg-4) to BS 304. At 706, UE 302 and BS 304 may exchange user data in some cases. The processing of Msg-A and Msg-B is otherwise equivalent to the processing of Msg-1, Msg-2, Msg-3, and Msg-4 in the 4-step PRACH procedure 600 of FIG. 6.

[0284]

[0290] In some designs, the 2-step or 4-step RACH procedure may be triggered by a PDCCH command. In the case of PRACH transmission triggered by a PDCCH command, the PRACH mask index field [5, TS 38.212] indicates a PRACH occasion for PRACH transmission if the value of the random access preamble index field is not 0, where the PRACH occasion is associated with the SS / PBCH block index indicated by the SS / PBCH block index field of the PDCCH command. When random access is triggered by a PDCCH command, the UE transmits a PRACH at the selected PRACH occasion if requested via a higher layer signal [TS 38.321], and for this occasion, the time between the last symbol of PDCCH command reception and the first symbol of PRACH transmission is >=N T,2 +Δ BWPSwitch +Δ Delay and where these parameters are defined in section 8.1 of TS 38.213.

[0285]

[0291] When the CRC of DCI format 1_0 is scrambled by C-RNTI and all bits in the "Frequency Domain Resource Allocation" field are 1, DCI format 1_0 is for the random access procedure initiated by a PDCCH command, and all the remaining fields are set as follows.

[0286] · Random access preamble index - 6 bits by ra-PreambleIndex in clause 5.1.2 of [8, TS38.321] · UL / SUL indicator - 1 bit. If the value of "Random access preamble index" is not all 0 and the UE is configured with supplementaryUplink in ServingCellConfig in the cell, this field indicates which UL carrier in the cell should transmit the PRACH according to Table 7.3.1.1.1-1; otherwise, this field is reserved.

[0287] · SS / PBCH index - 6 bits. If the value of "Random access preamble index" is not all zero, this field indicates the SS / PBCH used to determine the RACH occasion for PRACH transmission; otherwise, this field is reserved.

[0288] · PRACH mask index - 4 bits. If the value of "Random access preamble index" is not all 0, this field indicates the RACH occasion related to the SS / PBCH indicated by the "SS / PBCH index" for PRACH transmission according to clause 5.1.1 of [8, TS38.321]; otherwise, this field is reserved.

[0289] · Reserved bits - 12 bits for operation in cells using shared spectrum channel access, 10 bits otherwise.

[0290]

[0292] As will be described in more detail below with respect to various embodiments of the present disclosure, a modified version of a PDCCH-triggered RACH procedure can be implemented in which a partial RACH procedure, rather than a complete RACH procedure, is triggered by a PDCCH. In some designs, the partial RACH procedure can be used, particularly for positioning. As described above, such embodiments provide a technical advantage of providing a rough location estimate for further speed, particularly in scenarios where an active SRS configuration is not set up for the UE. Moreover, the use of a partial RACH procedure rather than a complete RACH procedure can reduce system overhead (e.g., since only the RACH / PRACH preamble or Msg-1 / Msg-A need to be transmitted) and improve spectral efficiency.

[0291]

[0293] FIG. 8 shows an exemplary process 800 of wireless communication according to an aspect of the present disclosure. Process 800 can be performed by UE 302.

[0292]

[0294] At 802, UE 302 (e.g., receiver 312, etc.) receives PDCCH communication. For example, the PDCCH communication can be received from serving BS 304 as part of DCI communication. In one example, the means for performing the reception of 802 can include receiver 312.

[0293]

[0295] At 804, the UE 302 (e.g., RACH component 344, processing system 332, transmitter 310, etc.) transmits a partial RACH procedure in response to PDCCH communication. In one example, the partial RACH procedure may include transmitting a RACH signal for positioning (e.g., Msg-1 or Msg-A transmission), while the partial RACH procedure is restricted with respect to RACH procedures 600 - 700 in the sense that the RACH procedure stops after transmitting the RACH preamble (e.g., Msg-2, Msg-3, Msg-4 are not transmitted for a 4-step PRACH procedure, or Msg-B is not transmitted for a 2-step PRACH procedure). In other designs, the partial RACH procedure may be triggered for purposes not related to positioning, such as coverage extension or UL beam sounding, or alternatively, may be triggered as a combination of both positioning and coverage extension or UL beam sounding. In one example, the means for performing the transmission at 804 may include transmitter 310.

[0294]

[0296] Figure 9 shows an exemplary process 900 of wireless communication according to an aspect of the present disclosure. Process 900 may be performed by BS 304, which may be the serving BS of UE 302.

[0295]

[0297] At 902, BS 304 (e.g., transmitter 316, etc.) transmits PDDCH communication configured to trigger a partial RACH procedure to UE 302. In one example, the means for performing the transmission at 902 may include transmitter 316.

[0296]

[0298] At 904, BS304 (such as receiver 318, etc.) receives a RACH transmission from UE302 in response to PDCCH communication. In one example, the RACH transmission may correspond to a Msg-1 or Msg-A transmission, while in the partial RACH procedure, the RACH procedure is restricted with respect to RACH procedures 600 - 700 in the sense that the RACH procedure stops after the RACH preamble transmission (e.g., Msg-2, Msg-3, Msg-4 are not transmitted for a 4-step PRACH procedure, or Msg-B is not transmitted for a 2-step PRACH procedure). In some designs, the RACH transmission may correspond to a RACH transmission for positioning, and BS304 performs positioning measurements thereon. In other designs, the partial RACH procedure may be triggered for purposes not related to positioning, such as coverage expansion or UL beam sounding, or alternatively, may be triggered as a combination of both positioning and coverage expansion or UL beam sounding. In some designs where the RACH transmission is a RACH transmission for positioning, BS304 may notify (e.g., via a backhaul connection) one or more non-serving BSs of 302 regarding the RACH transmission so that the non-serving BSs can also perform positioning measurements on the RACH transmission (which may be reported to a positioning entity such as an LMF integrated with BS304 or remote from BS304). In one example, the means for performing the reception at 904 may include receiver 318.

[0297]

[0299] FIG. 10 shows an exemplary process 1000 of wireless communication according to an aspect of the present disclosure. Process 1000 may be performed by BS304, which may be a non-serving BS of UE302.

[0298]

[0300] At 1002, BS304 (such as, for example, receiver 324) receives from the UE an indication of RACH transmission associated with a partial RACH procedure. In some designs, the indication at 1002 can be received from the serving BS of UE302 via a backhaul connection. In one example, the means for performing the reception at 1002 can include receiver 324.

[0299]

[0301] At 1004, BS304 (such as, for example, receiver 318) receives a RACH transmission based on the indication. In some designs, the RACH transmission can correspond to a RACH transmission for positioning, and BS304 can perform positioning measurements thereon (which can be reported, for example, to a positioning entity such as an LMF integrated with BS304 or remote from BS304). In one example, the means for performing the reception at 1004 can include receiver 318.

[0300]

[0302] FIG. 11 shows an exemplary process 1100 of wireless communication according to an aspect of the present disclosure. Process 1100 can be implemented, in some designs, by a positioning entity such as an LMF that can be integrated with BS304 (such as, for example, the serving BS of UE302) or alternatively remote from BS304, such as network entity 306. In other designs, the positioning entity can correspond to the UE itself (such as, for example, for UE-based positioning).

[0301]

[0303] At 1102, a position estimation entity 302 / 304 / 306 (e.g., RACH component 344 or 348, receiver 312 or 318 or 324 or 330, etc.) receives measurement data based on one or more positioning measurements performed by a set of BSs on a positioning RACH transmission from the UE. In one example, the RACH transmission may be part of a partial RACH procedure, but in other designs, the RACH transmission may be part of a complete PDCCH-triggered RACH procedure in which the positioning measurements are performed. In one example, the means for performing the reception at 1102 may include RACH component 344 or 348, and / or receiver 312 or 318 or 324 or 330.

[0302]

[0304] At 1104, a position estimation entity 302 / 304 / 306 (e.g., positioning component 349 or processing system 332 or 334 or 336) determines an estimated position of the UE based at least in part on the measurement data. In one example, the means for performing the reception at 1104 may include positioning component 349 and / or processing system 332 or 334 or 336.

[0303]

[0305] FIG. 12 shows an exemplary implementation 1200 of processes 800 - 1100 according to one aspect of the present disclosure. In particular, the exemplary implementation 1200 relates to a scenario where the position estimation entity corresponds to an LMF integrated with serving BS 304.

[0304]

[0306] Referring to FIG. 12, at 1202, serving BS304 notifies the non-serving BS of the upcoming RACH transmission for positioning from UE302 (as in 1002 of FIG. 11 for example). At 1204, serving BS304 transmits a PDCCH configured to trigger a partial RACH procedure to UE302 (as in 802 of FIG. 8 or 902 of FIG. 9 for example). At 1206, UE302 transmits a PRACH preamble (such as Msg-1 or Msg-A) in response to the PDCCH from 1204. At 1208, serving BS304 performs positioning measurements on the PRACH preamble. At 1210, non-serving BS304 performs positioning measurements on the PRACH preamble. Since at 1212 the LMF is integrated with serving BS304 (as in 1102 of FIG. 11 for example), non-serving BS304 sends measurement data to the LMF of serving BS304. At 1214, the LMF of serving BS304 determines a positioning estimate of UE302 based on the measurement data received from the non-serving BS at 1212, and also determines measurement data obtained based on the positioning measurements from 1208 at serving BS304.

[0305]

[0307] FIG. 13 shows an exemplary implementation 1300 of processes 800 - 1100 according to one aspect of the present disclosure. In particular, the exemplary implementation 1300 relates to a scenario where the positioning entity corresponds to an LMF integrated with a network entity 306 remote from serving BS304 and non-serving BS304.

[0306]

[0308] Referring to FIG. 13, at 1302, the serving BS 304 notifies the non-serving BS of the upcoming RACH transmission for positioning from the UE 302 (as in 1002 of FIG. 11 for example). At 1304, the serving BS 304 transmits a PDCCH configured to trigger a partial RACH procedure to the UE 302 (as in 802 of FIG. 8 or 902 of FIG. 9 for example). At 1306, the UE 302 transmits a PRACH preamble (e.g., Msg-1 or Msg-A) in response to the PDCCH from 1304. At 1308, the serving BS 304 performs a positioning measurement on the PRACH preamble. At 1310, the non-serving BS 304 performs a positioning measurement on the PRACH preamble. Since the LMF is integrated with the network entity 306 at 1312 - 1314 (as in 1102 of FIG. 11 for example), the serving BS 304 and the non-serving BS 304 send measurement data to the LMF 306. At 1316, the LMF 306 determines a positioning estimate of the UE 302 based on the measurement data received at 1312 - 1314.

[0307]

[0309] Referring to FIGS. 8-13, in some designs, a partial RACH procedure may be triggered in response to the configuration of PDCCH communication. For example, the partial RACH procedure may be triggered in response to at least one field of the PDCCH communication. In some designs, at least one field may comprise a radio network temporary identifier (RNTI), or at least one field may be part of DCI communication, or any combination thereof. In some designs, at least one field in the DCI communication may comprise a first value, and the partial RACH procedure may comprise a RACH transmission having a first configuration based on the first value. Then, another DCI communication in which at least one field comprises a second value may be transported, and this another DCI communication triggers another partial RACH procedure comprising another RACH transmission having a second configuration based on the second value. For example, at least one field may be part of the existing DCI format 1_0 that is currently scrambled with a C-RNTI and FDRA that are all set to 1 for a PDCCH-ordered RA preamble, or instead may be scrambled with another bit combination (or value) to indicate RACH for positioning or a partial RACH procedure. For example, these first and second configurations may correspond to different configurations of one or more PRACH preambles (Msg-1 or Msg-A), including but not limited to the following.

[0308] · Preamble format, · Sequence length (shown as "L" in FIGS. 4A-4B, for example), · Numerology or subcarrier spacing (SCS), · Bandwidth, · Cyclic prefix (CP) duration, · Guard time (GT) duration, · Full length, and / or · Number of OFDM symbols

[0310] Referring to FIGS. 8 to 13, in some designs, the partial RACH procedure may be triggered in response to the size of the PDCCH communication (e.g., a new DCI size specific to RACH for positioning or the partial RACH procedure).

[0309]

[0311] Referring to FIGS. 8 to 13, in some designs, the PDCCH that triggers the partial RACH procedure may be part of a sequence of DCIs each associated with different parameters for transmitting multiple RACH instances (or multiple RACH procedures).

[0310]

[0312] Referring to FIGS. 8 to 13, in some designs, the partial RACH procedure may be part of a joint DL and UL positioning procedure. For example, the PDCCH of the DCI that triggers the downlink part (e.g., DL PRS transmission) of the joint DL and UL positioning procedure may be further configured to trigger the uplink part (e.g., UL RACH, or the partial RACH procedure for positioning) of the joint DL and UL positioning procedure.

[0311]

[0313] Referring to FIGS. 8 to 13, in some designs, the partial RACH procedure may comprise the following.

[0312] · An RACH transmission transmitted on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs) (e.g., two or more SSB indices are mapped to the same UL beam and the UE transmits only once), · RACH transmissions sent via one or more frequency layers for each one or more RACH occasions, provided that the number of one or more frequency layers is based on the number of configured frequency layers for the UE (e.g., in some designs, up to 4 frequency layers can be used for positioning, and the gNB can indicate RACH occasions on up to that number of configured frequency layers for the UE to transmit UL PRS. Note: Generally, parallel RACH transmissions are not enabled, and thus the UE may need to TDM transmissions across multiple frequencies), · Repeated transmission of RACH preambles over multiple RACH or PRACH occasions (e.g., if the PRACH occasions are on different frequency resources, this can improve the link budget and / or resolution), or · Any combination thereof

[0314] Referring to FIGS. 8 - 13, in some designs, the RACH procedure may be based on a timing offset indicated via PDCCH communication. For example, a timing offset related to UE Rx - Tx measurements or gNB Rx - Tx measurements (e.g., the hardware / circuit delay between the receiver and transmitter used in various positioning measurements such as RTT, TDOA, etc.). In another example, when the RACH signal is transmitted as part of the UL TDoA / AoA procedure, the gNB can provide relevant timing information to the LMF. In another example, when the RACH signal is transmitted as part of the RTT / AoD, either the gNB or the UE can provide timing information to the LMF (depending on the node that initiates the procedure). Since the LMF may generally not be aware of PDCCH command - based triggering, the serving gNB can notify the LMF and / or other nearby gNBs to listen for the UE's RACH transmissions (e.g., as in 1202 of FIG. 12 or 1302 of FIG. 13).

[0313]

[0315] Referring to FIGS. 8 to 13, in some designs where the RACH transmission of the partial RACH procedure includes Msg-A (e.g., the PRACH preamble for the two-step PRACH procedure), related information such as DL measurement or UL timing reference can be transmitted on the PUSCH (or Msg-3 component) of Msg-A, which can be decomposed at the timing in the serving BS 304.

[0314]

[0316] Referring to FIGS. 8 to 13, in some designs, the RACH transmission of the partial RACH procedure can be transmitted via an authorized spectrum approved for a specific radio access technology (RAT) (e.g., LTE, 5G NR, etc.). In other designs, the RACH transmission can be transmitted via a shared spectrum shared by multiple RATs (e.g., LTE, 5G NR, Wi-Fi (registered trademark) or 802.11, etc.).

[0315]

[0317] In the above detailed description, it can be seen that different features are grouped in examples. This mode of disclosure should not be understood as intending that the exemplary clauses have more features than those explicitly stated in each clause. Rather, various aspects of the present disclosure may include fewer than all the features of the individual exemplary clauses disclosed. Accordingly, the following clauses should be considered to be incorporated herein, and each clause can exist as a separate example by itself. Each dependent clause can refer to a specific combination with one of the other clauses in the clause, but the (one or more) aspects of that dependent clause are not limited to the specific combination. It will be understood that other exemplary clauses can also include combinations of (one or more) aspects of dependent clauses with the subject matter of any other dependent or independent clause, or combinations of any features with other dependent and independent clauses. Various aspects disclosed herein do not explicitly include these combinations unless it is explicitly stated or can be readily inferred that a particular combination (such as defining an element as both an insulator and a conductor, etc., conflicting aspects) is not intended. Further, it is also intended that aspects of a clause can be included in any other independent clause even if that clause is not directly subordinate to that independent clause.

[0316]

[0318] Implementation examples are described in the following numbered clauses.

[0317]

[0319] Clause 1. A method of operating a user equipment (UE), comprising receiving physical downlink control channel (PDCCH) communication and triggering a partial random access channel (RACH) procedure in response to the PDCCH communication.

[0318]

[0320] Clause 2. The method of Clause 1, wherein the partial RACH procedure comprises transmitting a RACH signal for positioning.

[0319]

[0321] Clause 3. The method of Clause 2, wherein the RACH signal for positioning targets at least one non-serving BS of the UE and the serving base station (BS) of the UE.

[0320]

[0322] Clause 4. Triggering is by any of the methods of Clauses 1 to 3 in response to the configuration of PDCCH communication.

[0321]

[0323] Clause 5. Triggering is by the method of Clause 4 in response to at least one field of PDCCH communication.

[0322]

[0324] Clause 6. The method of Clause 5, wherein at least one field comprises a Radio Network Temporary Identifier (RNTI), or at least one field is part of Downlink Control Information (DCI) communication, or any combination thereof.

[0323]

[0325] Clause 7. The method of any of Clauses 5 to 6, wherein at least one field in DCI communication comprises a first value, a partial RACH procedure comprises RACH transmission with a first configuration based on the first value, and further comprises receiving another DCI communication in which at least one field comprises a second value, and this another DCI communication triggers another partial RACH procedure comprising another RACH transmission with a second configuration based on the second value.

[0324]

[0326] Clause 8. Triggering is by any of the methods of Clauses 4 to 7 in response to the size of PDCCH communication.

[0325]

[0327] Clause 9. The method of any of Clauses 1 to 8, wherein the partial RACH procedure is a partial four-step RACH procedure, and wherein the partial RACH procedure comprises only transmission of a RACH preamble without a RACH response to the RACH preamble.

[0326]

[0328] Clause 10. The partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises transmitting a RACH preamble and PUSCH communication without a RACH response for the RACH preamble or physical uplink shared channel (PUSCH) communication, according to any of the methods of Clauses 1 to 9.

[0327]

[0329] Clause 11. The UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between reception and triggering, according to any of the methods of Clauses 1 to 10.

[0328]

[0330] Clause 12. The partial RACH procedure comprises RACH transmission transmitted on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the partial RACH procedure comprises RACH transmission transmitted via one or more frequency layers for each of one or more RACH occasions, the number of one or more frequency layers being based on the number of configured frequency layers for the UE, or the partial RACH procedure comprises transmitting repetitions of the RACH preamble over a plurality of RACH occasions, or any combination thereof, according to any of the methods of Clauses 1 to 11.

[0329]

[0331] Clause 13. The RACH procedure is based on a timing offset indicated via PDCCH communication, according to any of the methods of Clauses 1 to 12.

[0330]

[0332] Clause 14. The RACH procedure is implemented via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH procedure is implemented via a shared spectrum shared by a plurality of RATs, according to any of the methods of Clauses 1 to 13.

[0331]

[0333] Clause 15. A method according to any of Clauses 1 to 14, wherein a partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger a downlink part of the joint uplink and downlink positioning procedure.

[0332]

[0334] Clause 16. A method of operating a serving base station (BS) of a user equipment (UE), the method comprising: transmitting physical downlink control channel (PDCCH) communication configured to trigger a partial random access channel (RACH) procedure to the UE; and receiving an RACH transmission from the UE in response to the PDCCH communication.

[0333]

[0335] Clause 17. The method of Clause 16, further comprising performing one or more positioning measurements on the RACH transmission, wherein the RACH transmission is for positioning.

[0334]

[0336] Clause 18. The method of Clause 17, wherein a positioning RACH signal is targeted at a serving BS of the UE and at least one non-serving BS of the UE.

[0335]

[0337] Clause 19. The method of Clause 18, further comprising notifying at least one non-serving BS or a location management function (LMF) of a partial RACH procedure to facilitate the at least one non-serving BS performing a positioning measurement on the RACH transmission.

[0336]

[0338] Clause 20. The method according to any of Clauses 17 to 19, further comprising sending measurement data based on one or more positioning measurements to a position estimation entity.

[0337]

[0339] Clause 21. The method according to any of Clauses 16 to 20, wherein the PDCCH communication is configured to trigger a partial RACH procedure based on the configuration of the PDCCH communication.

[0338]

[0340] Clause 22. The method of Clause 21, wherein the PDCCH communication is configured to trigger a partial RACH procedure based on at least one field of the PDCCH communication.

[0339]

[0341] Clause 23. The method of Clause 22, wherein at least one field comprises a Radio Network Temporary Identifier (RNTI), or at least one field is part of a Downlink Control Information (DCI) communication, or any combination thereof.

[0340]

[0342] Clause 24. The method of Clause 23, wherein at least one field in the DCI communication has a first value, the RACH transmission is configured with a first configuration based on the first value, and at least one field further comprises transmitting another DCI communication having a second value, and this another DCI communication is configured to trigger another partial RACH procedure having another RACH transmission with a second configuration based on the second value.

[0341]

[0343] Clause 25. The method according to any one of Clauses 22 to 24, wherein the PDCCH communication is configured to trigger a partial RACH procedure based on the size of the PDCCH communication.

[0342]

[0344] Clause 26. The method according to any one of Clauses 16 to 25, wherein the partial RACH procedure is a partial 4-step RACH procedure, and wherein the partial RACH procedure comprises only receiving a RACH preamble without a RACH response to the RACH preamble.

[0343]

[0345] Clause 27. The method according to any one of Clauses 16 to 26, wherein the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises receiving a RACH preamble and a Physical Uplink Shared Channel (PUSCH) communication without a RACH response to the RACH preamble or the PUSCH communication.

[0344]

[0346] Clause 28. Any method of Clauses 16 to 27, wherein the UE does not have an active SRS configuration for triggering the transmission of a sounding reference signal (SRS) for positioning between transmission and reception.

[0345]

[0347] Clause 29. Any method of Clauses 16 to 28, wherein the RACH transmission is received on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the RACH transmission is received via one or more frequency layers for each of one or more RACH occasions, the number of one or more frequency layers being based on the number of configured frequency layers for the UE, or the RACH transmission comprises repetitions of RACH preambles over a plurality of RACH occasions, or any combination thereof.

[0346]

[0348] Clause 30. Any method of Clauses 16 to 29, wherein the RACH procedure may be based on a timing offset indicated via PDCCH communication.

[0347]

[0349] Clause 31. Any method of Clauses 16 to 30, wherein the RACH transmission is received via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by a plurality of RATs.

[0348]

[0350] Clause 32. Any method of Clauses 16 to 31, wherein a partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger the downlink part of the joint uplink and downlink positioning procedure.

[0349]

[0351] Clause 33. A method of operating a non-serving base station (BS) of a user equipment (UE), the method comprising: receiving, from the UE, an indication of a random access channel (RACH) transmission associated with a partial RACH procedure; and receiving the RACH transmission based on the indication.

[0350]

[0352] Clause 34. The method of clause 33, further comprising performing one or more positioning measurements on the RACH transmission, wherein the RACH transmission is for positioning.

[0351]

[0353] Clause 35. The method of clause 34, further comprising sending measurement data based on the one or more positioning measurements to a position estimation entity.

[0352]

[0354] Clause 36. The method according to any one of clauses 33 to 35, wherein the partial RACH procedure is a partial four-step RACH procedure, and wherein the partial RACH procedure comprises only transmission of a RACH preamble without a RACH response to the RACH preamble.

[0353]

[0355] Clause 37. The method according to any one of clauses 33 to 36, wherein the partial RACH procedure is a partial two-step RACH procedure, and wherein the partial RACH procedure comprises transmission of a RACH preamble and a physical uplink shared channel (PUSCH) communication without a RACH response to the RACH preamble or the PUSCH communication.

[0354]

[0356] Clause 38. The method according to any one of clauses 33 to 37, wherein the RACH transmission is received via an authorized spectrum authorized for a particular radio access technology (RAT), or wherein the RACH transmission is received via a shared spectrum shared by a plurality of RATs.

[0355]

[0357] Clause 39. The method according to any one of clauses 16 to 38, wherein the partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure.

[0356]

[0358] Clause 40. A method of operating a location estimation entity, the method comprising: receiving measurement data based on one or more positioning measurements performed by a set of base stations (BSs) on a positioning random access channel (RACH) transmission from a user equipment (UE); and determining a positioning estimate of the UE based at least in part on the measurement data.

[0357]

[0359] Clause 41. The method of clause 40, wherein the RACH transmission is associated with a partial RACH procedure.

[0358]

[0360] Clause 42. The method of clause 41, wherein the partial RACH procedure is triggered by physical downlink control channel (PDCCH) communication from the serving BS of the UE.

[0359]

[0361] Clause 43. The method according to any one of clauses 41 to 42, wherein the partial RACH procedure is a partial 4-step RACH procedure, wherein the partial RACH procedure comprises only transmission of a RACH preamble without a RACH response to the RACH preamble.

[0360]

[0362] Clause 44. The method according to any one of clauses 41 to 43, wherein the partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises transmission of a RACH preamble and PUSCH communication without a RACH response to the RACH preamble or the PUSCH communication.

[0361]

[0363] Clause 45. The method according to any one of clauses 41 to 44, wherein the RACH transmission for positioning is transmitted by the UE via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by a plurality of RATs.

[0362]

[0364] Clause 46. An apparatus comprising a memory and at least one processor communicatively coupled to the memory, wherein the memory and the at least one processor are configured to perform the method according to any one of Clauses 1 to 45.

[0363]

[0365] Clause 47. An apparatus comprising means for performing the method according to any one of Clauses 1 to 45.

[0364]

[0366] Clause 48. A non-transitory computer-readable medium storing computer-executable instructions, the computer-executable including at least one instruction for causing a computer or processor to perform the method according to any one of Clauses 1 to 45.

[0365]

[0367] Those skilled in the art will appreciate that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0366]

[0368] Furthermore, those skilled in the art will appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the aspects disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described generally in terms of their functionality above. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in varying ways for each particular application, but such implementations should not be construed as departing from the scope of the present disclosure.

[0367]

[0369] With respect to the aspects disclosed herein, the various exemplary logical blocks, modules, and circuits described may be implemented or performed using a general purpose processor, a DSP, an ASIC, an FPGA, or other programmable logic device, discrete gates or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0368]

[0370] The methods, sequences and / or algorithms described with respect to the aspects disclosed herein may be implemented directly in hardware, in software modules executed by a processor, or in a combination of the two. Software modules may reside in RAM, flash memory, ROM, erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM (registered trademark)), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal (e.g., a UE). In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

[0369]

[0371] In one or more exemplary embodiments, the described functions may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted via a computer-readable medium as one or more instructions or code. A computer-readable medium includes both a computer storage medium and a communication medium including any medium that facilitates transfer of a computer program from one place to another. The storage medium may be any available medium that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Any connection is properly a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, where disk typically magnetically reproduces data and disc optically reproduces data with a laser. The above combinations should also be included within the scope of computer-readable media.

[0370]

[0372] The above disclosure shows exemplary aspects of the present disclosure, but it should be noted that various changes and modifications can be made herein without departing from the scope of the present disclosure as defined by the appended patent claims. The functions, steps, and / or actions of the method claims according to the aspects of the present disclosure described herein need not be performed in a particular order. Further, elements of the present disclosure may be described or claimed in the singular, but the plural is contemplated unless explicitly stated to be limited to the singular. The invention described in the claims of the present application at the time of filing is appended below. [C1] A method for operating a user equipment (UE), comprising: receiving physical downlink control channel (PDCCH) communication; and triggering a partial random access channel (RACH) procedure in response to the PDCCH communication. The method as described above. [C2] The method according to C1, wherein the partial RACH procedure comprises transmitting a RACH signal for positioning. [C3] The method according to C2, wherein the RACH signal for positioning targets at least one non-serving BS of the UE and a serving base station (BS) of the UE. [C4] The method according to C1, wherein the triggering is in response to a configuration of the PDCCH communication. [C5] The method according to C4, wherein the triggering is in response to at least one field of the PDCCH communication. [C6] The at least one field comprises a radio network temporary identifier (RNTI), or the at least one field is part of downlink control information (DCI) communication, or any combination thereof. The method according to C5. [C7] The at least one field in the DCI communication has a first value, and the partial RACH procedure comprises RACH transmission with a first configuration based on the first value. The method further comprises receiving another DCI communication in which the at least one field has a second value, and the another DCI communication triggers another partial RACH procedure comprising another RACH transmission with a second configuration based on the second value. The method according to C6. [C8] The method according to C4, wherein the triggering is in response to a size of the PDCCH communication. [C9] The partial RACH procedure is a partial 4-step RACH procedure, and the partial RACH procedure comprises only transmitting the RACH preamble without a RACH response to the RACH preamble. The method according to C1. [C10] The partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises transmitting the RACH preamble and the PUSCH communication without a RACH response for the RACH preamble or physical uplink shared channel (PUSCH) communication. The method according to C1. [C11] The method according to C1, wherein the UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between the receiving and the triggering. [C12] The partial RACH procedure comprises RACH transmission transmitted on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the partial RACH procedure comprises RACH transmission transmitted via one or more frequency layers for each of one or more RACH occasions, and the number of the one or more frequency layers is based on the number of configured frequency layers for the UE, or the partial RACH procedure comprises transmitting repetitions of the RACH preamble over a plurality of RACH occasions, or any combination thereof. The method according to C1. [C13] The RACH procedure is based on a timing offset indicated via the PDCCH communication, according to the method of C1. [C14] The RACH procedure is implemented via an authorized spectrum authorized for a specific radio access technology (RAT), or The RACH procedure is implemented via a shared spectrum shared by a plurality of RATs. The method according to C1. [C15] The partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure, The PDCCH is further configured to trigger a downlink part of the joint uplink and downlink positioning procedure. The method according to C1. [C16] A method for operating a serving base station (BS), comprising: transmitting physical downlink control channel (PDCCH) communication configured to trigger a partial random access channel (RACH) procedure to a user equipment (UE); receiving RACH transmission from the UE in response to the PDCCH communication; A method comprising... [C17] The RACH transmission is for positioning, further comprising performing one or more positioning measurements on the RACH transmission, the method according to C16. The method according to C16. [C18] The RACH signal for positioning targets the serving BS of the UE and at least one non-serving BS of the UE, the method according to C17. [C19] Notifying the at least one non-serving BS or a Location Management Function (LMF) of the partial RACH procedure to facilitate the at least one non-serving BS performing a positioning measurement on the RACH transmission, further comprising the method according to C18. [C20] Sending measurement data based on the one or more positioning measurements to a location estimation entity, further comprising the method according to C17. [C21] The PDCCH communication is configured to trigger the partial RACH procedure based on the configuration of the PDCCH communication, the method according to C16. [C22] The PDCCH communication is configured to trigger the partial RACH procedure based on at least one field of the PDCCH communication, the method according to C21. [C23] The at least one field comprises a Radio Network Temporary Identifier (RNTI), or the at least one field is part of a Downlink Control Information (DCI) communication, or any combination thereof, the method according to C22. [C24] The at least one field in the DCI communication has a first value, and the RACH transmission is configured with a first configuration based on the first value, further comprising transmitting another DCI communication in which the at least one field has a second value, the another DCI communication being configured to trigger another partial RACH procedure comprising another RACH transmission having a second configuration based on the second value, the method according to C23. [C25] The PDCCH communication is configured to trigger the partial RACH procedure based on the size of the PDCCH communication, the method according to C22. [C26] The partial RACH procedure is a partial 4-step RACH procedure, and the partial RACH procedure comprises only receiving the RACH preamble without a RACH response to the RACH preamble. The method according to C16. [C27] The partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises receiving the RACH preamble and the PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication. The method according to C16. [C28] The UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between the transmitting and the receiving, the method according to C16. [C29] The RACH transmission is received on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or the RACH transmission is received via one or more frequency layers for each of one or more RACH occasions, and the number of the one or more frequency layers is based on the number of configured frequency layers for the UE, or the RACH transmission comprises repetitions of the RACH preamble over a plurality of RACH occasions, or any combination thereof. The method according to C16. [C30] The RACH procedure may be based on a timing offset indicated via the PDCCH communication, the method according to C16. [C31] The RACH transmission is received via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by a plurality of RATs. The method according to C16. [C32] The partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure, the PDCCH is further configured to trigger a downlink part of the joint uplink and downlink positioning procedure. The method according to C16. [C33] A method for operating a non-serving base station (BS), Receiving, from a user equipment (UE), an indication of a random access channel (RACH) transmission associated with a partial RACH procedure; Receiving the RACH transmission based on the indication; A method comprising the above. [C34] The RACH transmission is for positioning; Further comprising performing one or more positioning measurements on the RACH transmission. The method according to C33; The method according to C33. [C35] The method according to C34, further comprising sending measurement data based on the one or more positioning measurements to a position estimation entity. [C36] The partial RACH procedure is a partial four-step RACH procedure, and the partial RACH procedure comprises only transmission of the RACH preamble without a RACH response to the RACH preamble. The method according to C33. [C37] The partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises transmission of the RACH preamble and the physical uplink shared channel (PUSCH) communication without a RACH response to the RACH preamble or the PUSCH communication. The method according to C33. [C38] The RACH transmission is received via an authorized spectrum authorized for a specific radio access technology (RAT), or The RACH transmission is received via a shared spectrum shared by a plurality of RATs. The method according to C33. [C39] The partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure according to C16. [C40] A method of operating a position estimation entity, comprising: Receiving, from a user equipment (UE), measurement data based on one or more positioning measurements performed by a set of base stations (BSs) on a positioning random access channel (RACH) transmission; Determining a positioning estimate of the UE based at least in part on the measurement data; A method comprising the above. [C41] The method according to C40, wherein the RACH transmission is associated with a partial RACH procedure. [C42] The method according to C41, wherein the partial RACH procedure is triggered by physical downlink control channel (PDCCH) communication from a serving BS of the UE. [C43] The partial RACH procedure is a partial 4-step RACH procedure, and the partial RACH procedure comprises only the transmission of the RACH preamble without a RACH response to the RACH preamble. The method according to C41. [C44] The partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises the transmission of the RACH preamble and the PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication. The method according to C41. [C45] The RACH transmission for positioning is transmitted by the UE via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by a plurality of RATs. The method according to C41. [C46] A user equipment (UE), a memory, a communication interface, and at least one processor communicatively coupled to the memory and the communication interface, wherein the at least one processor is configured to receive physical downlink control channel (PDCCH) communication via the communication interface, and configured to trigger a partial random access channel (RACH) procedure in response to the PDCCH communication. The UE thus configured. [C47] The partial RACH procedure of the UE according to C46 comprises the transmission of a RACH signal for positioning. [C48] The RACH signal for positioning of the UE according to C47 targets the serving base station (BS) of the UE and at least one non-serving BS of the UE. [C49] The triggering of the UE according to C46 is in response to the configuration of the PDCCH communication. [C50] The triggering of the UE according to C49 is in response to at least one field of the PDCCH communication. [C51] The at least one field comprises a radio network temporary identifier (RNTI), or the at least one field is part of downlink control information (DCI) communication, or any combination thereof. The UE according to C50. [C52] At least one field in the DCI communication has a first value, and the partial RACH procedure comprises RACH transmission having a first configuration based on the first value. It further comprises receiving, via the communication interface, another DCI communication in which the at least one field has a second value, the another DCI communication triggering another partial RACH procedure comprising another RACH transmission having a second configuration based on the second value. The UE according to C51. [C53] The triggering is in response to the size of the PDCCH communication, the UE according to C49. [C54] The partial RACH procedure is a partial 4-step RACH procedure, and the partial RACH procedure comprises only transmission of the RACH preamble without a RACH response to the RACH preamble. The UE according to C46. [C55] The partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises transmission of the RACH preamble and the PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication. The UE according to C46. [C56] The UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between the receiving and the triggering, the UE according to C46. [C57] The partial RACH procedure comprises RACH transmission transmitted on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or The partial RACH procedure comprises RACH transmission transmitted via one or more frequency layers for each of one or more RACH occasions, the number of the one or more frequency layers being based on the number of configured frequency layers for the UE, or The partial RACH procedure comprises repeated transmission of RACH preambles over a plurality of RACH occasions, or Any combination thereof. The UE according to C46. [C58] The RACH procedure is based on a timing offset indicated via the PDCCH communication, the UE according to C46. [C59] The RACH procedure is performed via an authorized spectrum approved for a specific radio access technology (RAT), or the RACH procedure is performed via a shared spectrum shared by multiple RATs, the UE according to C46. [C60] The partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure, the PDCCH is further configured to trigger a downlink part of the joint uplink and downlink positioning procedure, the UE according to C46. [C61] A base station, a memory, a communication interface, at least one processor communicatively coupled to the memory and the communication interface, wherein the at least one processor is configured to transmit physical downlink control channel (PDCCH) communication to trigger a partial random access channel (RACH) procedure for a user equipment (UE), receive an RACH transmission from the UE via the communication interface in response to the PDCCH communication, a base station configured to cause the communication interface to perform the above. [C62] The RACH transmission is for positioning, the at least one processor is further configured to perform one or more positioning measurements on the RACH transmission, the base station according to C61. [C63] The RACH signal for positioning targets the serving BS of the UE and at least one non-serving BS of the UE, the base station according to C62. [C64] The at least one processor is further configured to notify the at least one non-serving BS or a location management function (LMF) of the partial RACH procedure to facilitate the at least one non-serving BS to perform positioning measurements on the RACH transmission, the base station according to C63. [C65] The at least one processor is further configured to cause the communication interface to send measurement data based on the one or more positioning measurements to a position estimation entity, the base station according to C62. [C66] The base station according to C61, wherein the PDCCH communication is configured to trigger the partial RACH procedure based on the configuration of the PDCCH communication. [C67] The base station according to C66, wherein the PDCCH communication is configured to trigger the partial RACH procedure based on at least one field of the PDCCH communication. [C68] The at least one field comprises a Radio Network Temporary Identifier (RNTI), or the at least one field is part of Downlink Control Information (DCI) communication, or is any combination thereof, The base station according to C67. [C69] The at least one field in the DCI communication has a first value, and the RACH transmission is configured with a first configuration based on the first value. [C70] The at least one processor is further configured to cause the communication interface to transmit another DCI communication in which the at least one field has a second value, the another DCI communication being configured to trigger another partial RACH procedure comprising another RACH transmission having a second configuration based on the second value. The base station according to C68. [C70] The base station according to C67, wherein the PDCCH communication is configured to trigger the partial RACH procedure based on the size of the PDCCH communication. [C71] The partial RACH procedure is a partial 4-step RACH procedure, and the partial RACH procedure comprises only reception of the RACH preamble without a RACH response to the RACH preamble. The base station according to C61. [C72] The partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure comprises reception of the RACH preamble and the PUSCH communication without a RACH response to the RACH preamble or the Physical Uplink Shared Channel (PUSCH) communication. The base station according to C61. [C73] The base station according to C61, wherein the UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between the transmitting and the receiving. [C74] The RACH transmission is received on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), or, the RACH transmission is received via one or more frequency layers for each of one or more RACH occasions, and the number of the one or more frequency layers is based on the number of configured frequency layers for the UE, or, the RACH transmission comprises repetitions of RACH preambles over a plurality of RACH occasions, or, any combination thereof, The base station according to C61. [C75] The RACH procedure may be based on a timing offset indicated via the PDCCH communication. The base station according to C61. [C76] The RACH transmission is received via an authorized spectrum authorized for a specific radio access technology (RAT), or, the RACH transmission is received via a shared spectrum shared by a plurality of RATs, The base station according to C61. [C77] The partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure, the PDCCH is further configured to trigger a downlink part of the joint uplink and downlink positioning procedure, The base station according to C61. [C78] The partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure. The base station according to C55. [C79] A base station, a memory, a communication interface, at least one processor communicatively coupled to the memory and the communication interface, wherein the at least one processor is configured to receive, from a user equipment (UE) via the communication interface, an indication of an RACH transmission associated with a partial random access channel (RACH) procedure, receive the RACH transmission based on the indication via the communication interface, A base station configured to perform. [C80] The RACH transmission is for positioning, the at least one processor is further configured to perform one or more positioning measurements on the RACH transmission, The base station according to C79. [C81] The at least one processor is The base station according to C80, further configured to cause the communication interface to send measurement data based on the one or more positioning measurements to a position estimation entity. [C82] The partial RACH procedure is a partial 4-step RACH procedure, and the partial RACH procedure includes only transmission of the RACH preamble without a RACH response to the RACH preamble. The base station according to C79. [C83] The partial RACH procedure is a partial 2-step RACH procedure, and the partial RACH procedure includes transmission of the RACH preamble and the PUSCH communication without a RACH response to the RACH preamble or the physical uplink shared channel (PUSCH) communication. The base station according to C79. [C84] The RACH transmission is received via an authorized spectrum authorized for a specific radio access technology (RAT), or The RACH transmission is received via a shared spectrum shared by a plurality of RATs. The base station according to C79. [C85] A position estimation entity, A memory, A communication interface, At least one processor communicatively coupled to the memory and the communication interface, the at least one processor is configured to: Receive, via the communication interface, measurement data based on one or more positioning measurements performed by a set of base stations (BSs) for a random access channel (RACH) transmission for positioning from a user equipment (UE); Determine a positioning estimate of the UE based at least in part on the measurement data; A position estimation entity configured to perform the above. [C86] The RACH transmission is related to a partial RACH procedure, and the position estimation entity according to C85. [C87] The partial RACH procedure is triggered by physical downlink control channel (PDCCH) communication from a serving BS of the UE, and the position estimation entity according to C86. [C88] The partial RACH procedure is a partial 4-step RACH procedure, and the partial RACH procedure includes only transmission of the RACH preamble without a RACH response to the RACH preamble. The location estimation entity described in C86. [C89] The partial RACH procedure is a partial two-step RACH procedure, and the partial RACH procedure comprises transmitting the RACH preamble and the PUSCH communication without a RACH response for the RACH preamble or physical uplink shared channel (PUSCH) communication. The location estimation entity described in C86. [C90] The RACH transmission for positioning is transmitted by the UE via an authorized spectrum authorized for a specific radio access technology (RAT), or the RACH transmission is received via a shared spectrum shared by a plurality of RATs. The location estimation entity described in C86.

Claims

1. A method for operating a user equipment (UE), comprising: receiving physical downlink control channel (PDCCH) communication; triggering a partial random access channel (RACH) procedure in response to the PDCCH communication; wherein the partial RACH procedure comprises RACH transmissions sent on one or more beams corresponding to a plurality of synchronization signal blocks (SSBs), wherein two or more SSB indexes are mapped to the same uplink beam, and / or the partial RACH procedure comprises RACH transmissions sent via a plurality of frequency layers for each of one or more RACH occasions, the number of the plurality of frequency layers being based on the number of configured frequency layers for the UE. The method.

2. The method according to claim 1, wherein the partial RACH procedure comprises transmitting a RACH signal for positioning.

3. The method according to claim 2, wherein the RACH signal for positioning targets the serving base station (BS) of the UE and at least one non-serving BS of the UE.

4. The method according to claim 1, wherein the triggering is in response to the configuration of the PDCCH communication.

5. The method according to claim 4, wherein the triggering is in response to at least one field of the PDCCH communication.

6. The at least one field comprises a radio network temporary identifier (RNTI), or the at least one field is part of downlink control information (DCI) communication, or any combination thereof. The method according to claim 5.

7. The at least one field in the DCI communication has a first value, and the partial RACH procedure comprises RACH transmissions having a first configuration based on the first value. The method further comprises receiving another DCI communication in which the at least one field has a second value, the another DCI communication triggering another partial RACH procedure comprising another RACH transmission having a second configuration based on the second value. The method according to claim 6.

8. The method according to claim 4, wherein the triggering is in response to the size of the PDCCH communication.

9. The partial RACH procedure comprises transmission of a RACH preamble and physical uplink shared channel (PUSCH) communication. The method according to claim 1.

10. The method according to claim 1, wherein the UE does not have an active SRS configuration for triggering transmission of a sounding reference signal (SRS) for positioning between the receiving and the triggering.

11. The partial RACH procedure comprises repeated transmission of a RACH preamble over a plurality of RACH occasions. The method according to claim 1.

12. The partial RACH procedure is performed via an authorized spectrum approved for a specific radio access technology (RAT), or The partial RACH procedure is performed via a shared spectrum shared by a plurality of RATs. The method according to claim 1.

13. The partial RACH procedure is an uplink part of a joint uplink and downlink positioning procedure, and the PDCCH is further configured to trigger a downlink part of the joint uplink and downlink positioning procedure. The method according to claim 1.

14. A user equipment (UE) comprising: a memory; a communication interface; and at least one processor communicatively coupled to the memory and the communication interface, the at least one processor being configured to: receive physical downlink control channel (PDCCH) communication via the communication interface; and trigger a partial random access channel (RACH) procedure in response to the PDCCH communication. The partial RACH procedure comprises RACH transmission transmitted on one or more beams corresponding to a plurality of synchronization signal blocks (SSB), wherein two or more SSB indexes are mapped to the same uplink beam. The partial RACH procedure comprises RACH transmission transmitted via a plurality of frequency layers for each of one or more RACH occasions, the number of the plurality of frequency layers being based on the number of configured frequency layers for the UE. UE.

15. ​ The UE according to claim 14, wherein the at least one processor is further configured to execute the method according to any one of claims 2 to 13.

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