WO2024077443A1

WO2024077443A1 - Method of user equipment triggering global navigation satellite system measurement

Info

Publication number: WO2024077443A1
Application number: PCT/CN2022/124371
Authority: WO
Inventors: Jingyuan Sun; Mads LAURIDSEN; Ping Yuan
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2022-10-10
Filing date: 2022-10-10
Publication date: 2024-04-18

Abstract

Systems, methods, apparatuses, and computer program products for UE triggering global navigation satellite system measurements. One method may include estimating at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal; determining that at least one of the downlink time error or downlink frequency error is larger than a threshold; and transmitting, to a network entity, an indication of global navigation satellite system related information.

Description

METHOD OF USER EQUIPMENT TRIGGERING GLOBAL NAVIGATION SATELLITE SYSTEM MEASUREMENT

TECHNICAL FIELD:

Some example embodiments may generally relate to mobile or wireless telecommunication systems, such as 3 ^rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) , 5 ^th generation (5G) radio access technology (RAT) , new radio (NR) access technology, 6 ^th generation (6G) , and/or other communications systems. For example, certain example embodiments may relate to systems and/or methods for a user equipment (UE) triggering global navigation satellite system (GNSS) measurements.

BACKGROUND:

Examples of mobile or wireless telecommunication systems may include radio frequency (RF) 5G RAT, the Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN) , LTE Evolved UTRAN (E-UTRAN) , LTE-Advanced (LTE-A) , LTE-A Pro, NR access technology, and/or MulteFire Alliance. 5G wireless systems refer to the next generation (NG) of radio systems and network architecture. A 5G system is typically built on a 5G NR, but a 5G (or NG) network may also be built on E-UTRA radio. It is expected that NR can support service categories such as enhanced mobile broadband (eMBB) , ultra-reliable low-latency-communication (URLLC) , and massive machine-type communication (mMTC) . NR is expected to deliver extreme broadband, ultra-robust, low-latency connectivity, and massive networking to support the Internet of Things (IoT) . The next generation radio access network (NG-RAN) represents the radio access network (RAN) for 5G, which may provide radio access for NR, LTE, and LTE-A. It is noted that the nodes in 5G providing radio access functionality to a user equipment (e.g., similar to the Node B in UTRAN or the Evolved Node B (eNB) in LTE) may be referred to as next- generation Node B (gNB) when built on NR radio, and may be referred to as next-generation eNB (NG-eNB) when built on E-UTRA radio.

SUMMARY:

In accordance with some example embodiments, a method may include estimating at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal. The method may further include determining that at least one of the downlink time error or downlink frequency error is larger than a threshold. The method may further include transmitting, to a network entity, an indication of global navigation satellite system (GNSS) related information.

In accordance with certain example embodiments, an apparatus may include means for estimating at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal. The apparatus may further include means for determining that at least one of the downlink time error or downlink frequency error is larger than a threshold. The apparatus may further include means for transmitting, to a network entity, an indication of global navigation satellite system (GNSS) related information.

In accordance with various example embodiments, a non-transitory computer readable medium may include program instructions that, when executed by an apparatus, cause the apparatus to perform at least a method. The method may include estimating at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal. The method may further include determining that at least one of the downlink time error or downlink frequency error is larger than a threshold. The method may further include transmitting, to a network entity, an indication of global navigation satellite system (GNSS) related information.

In accordance with some example embodiments, a computer program product may perform a method. The method may include estimating at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal. The method may further include determining that at least one of the downlink time error or downlink frequency error is larger than a threshold. The method may further include transmitting, to a network entity, an indication of global navigation satellite system (GNSS) related information.

In accordance with certain example embodiments, an apparatus may include at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to estimate at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal. The at least one memory and instructions, when executed by the at least one processor, may further cause the apparatus at least to determine that at least one of the downlink time error or downlink frequency error is larger than a threshold. The at least one memory and instructions, when executed by the at least one processor, may further cause the apparatus at least to transmit, to a network entity, an indication of global navigation satellite system (GNSS) related information.

In accordance with various example embodiments, an apparatus may include estimating circuitry configured to estimate at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal. The apparatus may further include determining circuitry configured to determine that at least one of the downlink time error or downlink frequency error is larger than a threshold. The apparatus may further include transmitting circuitry configured to transmit, to a network entity, an indication of global navigation satellite system (GNSS) related information.

In accordance with some example embodiments, a method may include receiving, from a user equipment, an indication of global navigation satellite system (GNSS) related information. The method may further include determining that the user equipment has GNSS information based on the indication of GNSS related information.

In accordance with certain example embodiments, an apparatus may include means for receiving, from a user equipment, an indication of global navigation satellite system (GNSS) related information. The apparatus may further include means for determining that the user equipment has GNSS information based on the indication of GNSS related information.

In accordance with various example embodiments, a non-transitory computer readable medium may include program instructions that, when executed by an apparatus, cause the apparatus to perform at least a method. The method may include receiving, from a user equipment, an indication of global navigation satellite system (GNSS) related information. The method may further include determining that the user equipment has GNSS information based on the indication of GNSS related information.

In accordance with some example embodiments, a computer program product may perform a method. The method may include receiving, from a user equipment, an indication of global navigation satellite system (GNSS) related information. The method may further include determining that the user equipment has GNSS information based on the indication of GNSS related information.

In accordance with certain example embodiments, an apparatus may include at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to receive, from a user equipment, an indication of global navigation satellite system (GNSS) related information. The at least one memory and instructions, when executed by the at least one processor, may further cause the apparatus at least to determine that the user equipment has GNSS information based on the indication of GNSS related information.

In accordance with various example embodiments, an apparatus may include receiving circuitry configured to receive, from a user equipment, an indication of global navigation satellite system (GNSS) related information. The apparatus may further include determining circuitry configured to determine that the user equipment has GNSS information based on the indication of GNSS related information.

BRIEF DESCRIPTION OF THE DRAWINGS:

For a proper understanding of example embodiments, reference should be made to the accompanying drawings, wherein:

FIG. 1 illustrates an example of a signaling diagram according to certain example embodiments;

FIG. 2 illustrates an example of a flow diagram of a method performed by a UE according to some example embodiments;

FIG. 3 illustrates an example of a flow diagram of a method performed by a network entity according to various example embodiments;

FIG. 4 illustrates an example of various network devices according to certain example embodiments; and

FIG. 5 illustrates an example of a 5G network and system architecture according to some example embodiments.

DETAILED DESCRIPTION:

It will be readily understood that the components of certain example embodiments, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of some example embodiments of systems, methods, apparatuses, and computer program products for UE triggering GNSS measurements is not intended to limit the scope of certain example embodiments, but is instead representative of selected example embodiments.

As a lower-Earth orbit, IoT non-terrestrial network (NTN) satellite moves, a UE may need to pre-compensate for time and frequency in uplink (UL) synchronization based on the location of the UE in relation to the GNSS, as well as the location of the satellite in relation to satellite ephemeris data (i.e., position and/or velocity information of the satellite over a predetermined duration of time) . In 3GPP Rel-17, the IoT NTN may include short sporadic transmissions. For example, before accessing the network, the UE may acquire GNSS position data, but may not need to reacquire a GNSS position for the transmission of the packets.

Currently, when a UE is in a radio resource control (RRC) connected mode and receiving/transmitting, the UE may not use its GNSS module, resulting in the UE being unaware of whether its location has moved. It would be advantageous to define how a UE can identify UE movement and trigger such GNSS measurements.

Certain example embodiments described herein may have various benefits and/or advantages to overcome the disadvantages described above. For example, in some example embodiments, a UE may always detect a change of location, even when no UL transmission is performed for a duration of time, and where the network may not know the UL synchronization status of the UE. Thus, certain example embodiments discussed below are directed to improvements in computer-related technology.

Some example embodiments described herein may enable a UE to trigger GNSS measurements by transmitting a pre-configured indication signal (e.g., physical random access channel (PRACH) -like signal as m-sequence, golden sequence, pseudo-random/pseudo-noise (PN) sequence, or PRACH sequence) when the UE detects a predicted downlink (DL) receiving time of a DL signal (e.g., primary synchronization signal (PSS) /secondary synchronization signal (SSS) ) having a time error more than a threshold compared to a received synchronization signal.

FIG. 1 illustrates an example of a signaling diagram for a UE triggering GNSS measurements. NE 120 and UE 110 may be similar to NE 410 and UE 420, as illustrated in FIG. 4, according to certain example embodiments.

At 101, NE 120 may detect that UE 110 has not transmitted a UL transmission for a predetermined duration of time (e.g., 5 seconds) . In response to the detection, at 102, NE 120 may transmit to UE 110 a configuration to start a measurement of DL time/frequency (T/F) error in a time duration (e.g., 100 ms) for triggering GNSS measurements and transmitting a preconfigured indication signal (e.g., similar to PRACH) to UE 110. The configuration may enable UE 110 to trigger new GNSS measurements, and/or T/F resources for transmission of this signal.

In some example embodiments, the preconfigured indication signal may be predefined but not configured by NE 120.

In some example embodiments, upon UE 110 detecting that UE 110 has not transmitted a UL transmission for a predetermined duration of time (e.g., 5 seconds) , UE 110 may begin a measurement of DL time/frequency (T/F) error in a time duration (e.g., 100 ms) for triggering GNSS measurements.

In certain example embodiments, NE 120 may configure UE 110 to measure the DL T/F error at any time, and to configure UE 110 to only measure the DL T/F after a duration of time (e.g., 5 seconds) since the last UL transmission by UE 110.

In some example embodiments, NE 120 may configure UE 110 to measure the DL T/F error when there are less than y seconds until the current GNSS validity duration expires (i.e., before the GNSS validity duration expires) .

In various example embodiments, NE 120 may configure UE 110 with an indication sequence (as indication signal) index as the trigger to request a new GNSS measurement if the detected DL T/F error is larger than a value that is unacceptable for GNSS accuracy. In addition, the time and frequency resource for the indication sequence (as indication signal) may be allocated to UE 110 within the time duration (e.g., on an UL slot 100 ms after the first reception of the first physical downlink shared channel (PDSCH) containing the configuration) . In addition, the frequency resource may be a valid frequency resource for UE 110 (e.g., the 1 physical resource block (PRB) for NB-IoT, or PRB n for enhanced machine type communication (eMTC) UE) . The indication signal and/or the PRACH-like sequence may be an m-sequence, golden sequence, or PN sequence. The resource for the PRACH-like sequence triggering may be a special resource for PRACH, which may not be used for PRACH.

At 103, UE 110 may detect the DL T/F error by measuring a synchronization signal (i.e., PSS/SSS) . UE 110 may also detect physical broadcast channel (PBCH) and demodulation reference signal (DMRS) of the PBCH for DL time error measurements in a time duration as configured by NE 120 and/or a time duration start from N slots after the end of the PDSCH with the network configuration for triggering of the UE measurement with a length of M slots. UE 110 may also measure the narrowband reference signal (NRS) and/or the narrowband positioning reference signal (NPRS) (for positioning) , if configured. UE 110 may also determine the system frame number (SFN) of the master information block (MIB) as a time reference. For example, when UE 110 is an eMTC device, a resynchronization signal (RSS) may be used to measure the T/F error.

UE 110 may evaluate the DL T/F error based on the received network configuration. For example, when UE 110 is in an RRC connected mode, UE 110 may receive synchronization signals for DL synchronization (e.g., PSS/SSS/NRS) .

In various example embodiments, UE 110 may predict the DL T/F for next synchronization signals based on its last measured GNSS location and a satellite’s location from ephemeris data. For example, the ephemeris data may be a new received ephemeris of a satellite or predicted during a ephemeris validity duration.

In certain example embodiments, UE 110 may calculate the T/F difference between a predicted receiving T/F and an actual receiving T/F of the DL signal, and designate the difference as the DL T/F error.

At 104, UE 110 may trigger a new GNSS measurement if the T/F error at 102 is larger than a threshold; thus, the GNSS of UE 110 may be invalid (i.e., inaccurate to calculate uplink pre-compensation (e.g., UE 110 has moved) ) .

In various example embodiments, UE 110 may also consider a remaining GNSS validity duration of the previous GNSS measurement, in addition to the DL T/F measurement. If UE 110 determines that the DL T/F difference is above a predetermined percentage of the error threshold (e.g., 80%) , and the remaining GNSS validity is below a threshold of y seconds, UE 110 may transmit the indication signal to trigger the GNSS measurement since the GNSS is likely to soon become invalid. The values of x and y may be configured by NE 120.

In certain example embodiments, UE 110 may consider the remaining GNSS validity duration (of the previous GNSS measurement) , in addition to the DL T/F measurement, if the remaining GNSS validity duration is larger than a threshold. UE 110 may transmit the indication sequence (as indication signal) to trigger NE 120 to schedule a GNSS measurement gap for new GNSS measurements. In contrast, if the remaining GNSS validity duration is smaller than a threshold, UE 110 may re-acquire GNSS immediately, and UE 110 may report the validity duration to NE 120 after the GNSS adjustment.

In some example embodiments, UE 110 may detect DL frequency errors or T/F errors; when the DL frequency error or T/F errors are larger than a threshold, UE 110 may trigger the new GNSS measurement.

In various example embodiments, UE 110 may be configured with PRACH transmissions as the trigger for new GNSS measurements.

However, if UE 110 determines that the time duration to acquire a GNSS adjustment is less than the threshold, UE 110 may re-acquire a GNSS adjustment immediately, and may report the validity duration to NE 120 after the GNSS adjustment.

At 105, UE 110 may evaluate the time duration required to re-acquire GNSS based on the GNSS channel status. When UE 110 detects that the detected DL time error is larger than a threshold (e.g., larger than Y) where the threshold can be configured by NE 120 or is pre-defined, UE 110 may initiate the triggering procedure for a new GNSS measurement. For example, in order for UE 110 to trigger a request for new GNSS measurements, UE 110 may transmit a preconfigured indication signal to NE 120 on the network configured resource. As an example, this indication signal may be transmitted as a different signal from other signals, thereby avoiding interference with other UE transmissions, such as PRACH.

In various example embodiments, the triggering from UE 110 may be based on a sequence selection. For example, UE 110 may be configured with multiple sequences representing different information, and UE 110 may transmit the selected sequence to transmit the corresponding information to NE 120, including, for example, whether new GNSS measurements are needed; how much the T/F error is; whether UE 110 detected movement of itself and how large the location difference is; and whether UE 110 needs more or less time (and how much) for GNSS measurements than the previous reported time requested.

At 106, NE 120 may configure UE 110 with a new GNSS measurement gap for the new GNSS measurement. For example, in response to NE 120 receiving the UE triggering at 105, NE 120 may decide, based on the triggering information from UE 110, to schedule and transmit a new GNSS measurement to UE 110. NE 120 may transmit a DL physical downlink control channel (PDCCH) /PDSCH to UE 110.

FIG. 2 illustrates an example of a flow diagram of a method for UE triggering GNSS measurements that may be performed by a UE, such as UE 420 illustrated in FIG. 4, according to various example embodiments.

At 201, after the UE has not transmitted a UL transmission for a predetermined duration of time (e.g., 5 seconds) , the method may include receiving, from a NE, such as NE 410 illustrated in FIG. 4, a configuration to start a measurement of DL T/F error in a time duration (e.g., 100 ms) for triggering GNSS measurements and transmitting a preconfigured indication signal (e.g., similar to PRACH) . The configuration may enable the UE to trigger new GNSS measurements, and/or T/F resources for transmission of this signal.

In some example embodiments, the preconfigured indication signal may be predefined but not configured by the NE.

In some example embodiments, upon the UE detecting that the UE has not transmitted a UL transmission for a predetermined duration of time (e.g., 5 seconds) , the UE may begin a measurement of DL T/F error in a time duration (e.g., 100 ms) for triggering GNSS measurements.

In certain example embodiments, the UE may be configured to measure the DL T/F error at any time, and to configure the UE to only measure the DL T/F after a duration of time (e.g., 5 seconds) since the last uplink transmission by the UE.

In some example embodiments, the UE may be configured by the NE to measure the DL T/F error when there are less than y seconds until the current GNSS validity duration expires (i.e., before the GNSS validity duration expires) .

In various example embodiments, the UE may be configured with an indication sequence (as indication signal) index as the trigger to request a new GNSS measurement if the detected DL T/F error is larger than a value that is unacceptable for GNSS accuracy. In addition, the time and frequency resource for the indication signal may be allocated to the UE within the time duration (e.g., on an UL slot 100 ms after the first reception of the first PDSCH containing the configuration) . In addition, the frequency resource may be a valid frequency resource for the UE (e.g., the 1 PRB for NB-IoT, or PRB n for eMTC UE) . The indication signal or the PRACH-like sequence may be an m-sequence, golden sequence, or PN sequence. The resource for the indication signal triggering may be a special resource for PRACH, which may not be used for PRACH.

At 202, the method may include detecting the DL T/F error by measuring a downlink signal (i.e., PSS/SSS) . The method may include detecting PBCH and DMRS of the PBCH for DL time error measurement in a time duration as configured by network or a time duration start from N slots after the end of the PDSCH with the network configuration for triggering of the UE measurement with a length of M slots. The method may also include measuring the NRS or the NPRS (for positioning) , if configured. The method may also include determining the SFN of the MIB as a time reference. For example, when the UE is an eMTC device, a RSS may be used to measure the T/F error.

In various example embodiments, the method may include evaluating the DL T/F error based on the received network configuration. For example, when the UE is in an RRC connected mode, the method may include receiving synchronization signals for DL synchronization (e.g., PSS/SSS/NRS) .

In various example embodiments, the method may include predicting the DL T/F for next synchronization signals based on its last measured GNSS location and the satellite’s location from ephemeris. For example, the ephemeris may be a new received ephemeris of satellite or predicted during ephemeris validity duration.

In certain example embodiments, the method may include calculating the T/F difference between a predicted receiving T/F and a real receiving T/F of the DL signal, and designating this difference as the DL T/F error.

At 203, the method may include triggering a new GNSS measurement if the T/F error at 201 is larger than a threshold; thus, the GNSS of the UE may be invalid (i.e., inaccurate to calculate uplink pre-compensation (e.g., the UE has moved) ) .

In various example embodiments, the method may include considering a remaining GNSS validity duration of the previous GNSS measurement, in addition to the DL T/F measurement. If the UE determines that the DL T/F difference is above a predetermined percentage of the error threshold (e.g., 80%) , and the remaining GNSS validity is below a threshold of y seconds, the method may include transmitting the indication signal to trigger the GNSS measurement since the GNSS is likely to soon become invalid. The values of x and y can be configured by the NE.

In certain example embodiments, the method may include considering the remaining GNSS validity duration (of the previous GNSS measurement) , in addition to the DL T/F measurement, if the remaining GNSS validity duration is larger than a threshold. The method may include transmitting the indication signal to trigger the NE to schedule GNSS measurement gap for new GNSS measurement. In contrast, if the remaining GNSS validity duration is smaller than a threshold, the method may include re-acquiring GNSS immediately, and reporting the validity duration to the NE after the GNSS adjustment.

In some example embodiments, upon detecting DL frequency errors or T/F errors, when the DL frequency error or T/F errors are larger than threshold, the method may include triggering the new GNSS measurement.

In various example embodiments, the UE may be configured with PRACH transmissions as the trigger for new GNSS measurement.

However, if the UE determines that the time duration to acquire a GNSS adjustment is less than the threshold, the method may include re-acquiring GNSS immediately, and may report the validity duration to the NE after the GNSS adjustment.

At 204, the method may include evaluating the time duration required to re-acquire GNSS based on the GNSS channel status. When the UE detects that the detected DL time error is larger than a threshold (e.g., larger than Y) where the threshold can be configured by the NE or pre-defined, the method may include initiating the triggering procedure for a new GNSS measurement. For example, in order for the UE to trigger a request for new GNSS measurements, the method may include transmitting a preconfigured indication signal to the NE on the network configured resource. As an example, this indication signal may be transmitted as a different signal from other signals, thereby avoiding interference with other UE transmissions, such as PRACH.

In various example embodiments, the triggering by the UE may be based on a sequence selection. For example, the UE may be configured with multiple sequences representing different information, and the UE may transmit the selected sequence to transmit the corresponding information to the NE, including, for example, whether new GNSS measurements are needed; how much the T/F error is; whether the UE detected movement of itself and how large the location difference is; and whether the UE needs more or less time (and how much) for GNSS measurements than the previous reported time requested.

At 205, the UE may be configured by the NE with a new GNSS measurement gap for the new GNSS measurement (e.g., DL PDCCH/PDSCH) . For example, in response to the NE receiving the UE triggering at 204, the UE may, based on the triggering information from the UE, receive a new GNSS measurement from the NE.

FIG. 3 illustrates an example of a flow diagram of a method for UE triggering GNSS measurements that may be performed by a NE, such as NE 410 illustrated in FIG. 4, according to various example embodiments.

At 301, the method may include detecting that a UE, such as UE 420 illustrated in FIG. 4, has not transmitted a UL transmission for a predetermined duration of time (e.g., 5 seconds) . In response to the detection, at 302, the method may include transmitting to the UE a configuration to start a measurement of DL T/F error in a time duration (e.g., 100 ms) for triggering GNSS measurements and preconfiguring signal (e.g., similar to PRACH) to the UE. The configuration may enable the UE to trigger new GNSS measurements, and/or T/F resources for transmission of this signal.

In certain example embodiments, the method may include configuring the UE to measure the DL T/F error at any time, and configuring the UE to only measure the DL T/F after a duration of time (e.g., 5 seconds) since the last uplink transmission by the UE.

In some example embodiments, the method may include configuring the UE to measure the DL T/F error when there are less than y seconds until the current GNSS validity duration expires (i.e., before the GNSS validity duration expires) .

In various example embodiments, the method may include configuring the UE with an indication sequence (as indication signal) index as the trigger to request a new GNSS measurement if the detected DL T/F error is larger than a value that is unacceptable for GNSS accuracy. In addition, the time and frequency resource for the indication sequence (as indication signal) may be allocated to the UE within the time duration (e.g., on an UL slot 100 ms after the first reception of the first PDSCH containing the configuration) . In addition, the frequency resource may be a valid frequency resource for the UE (e.g., the 1 PRB for NB-IoT, or PRB n for eMTC UE) . The indication signal or the PRACH-like sequence may be an m-sequence, golden sequence, or PN sequence. The resource for the indication signal triggering may be a special resource for PRACH, which may not be used for PRACH.

At 303, after the UE detects that a detected DL time error is larger than a threshold (e.g., larger than Y) where the threshold can be configured by the NE or pre-defined, the method may include initiating a triggering procedure for a new GNSS measurement. For example, in order for the UE to trigger a request for new GNSS measurements, the method may include receiving a preconfigured PRACH-like signal from the UE on the network configured resource. As an example, this PRACH-like signal may be received as a different signal from other signals, thereby avoiding interference with other UE transmissions, such as PRACH.

In various example embodiments, the triggering from the UE may be based on a sequence selection. For example, the UE may be configured with multiple sequences representing different information, and the NE may receive the selected sequence to transmit the corresponding information from the UE, including, for example, whether new GNSS measurements are needed; how much the T/F error is; whether the UE detected movement of itself and how large the location difference is; and whether the UE needs more or less time (and how much) for GNSS measurements than the previous reported time requested.

At 304, the method may include configuring the UE with a new GNSS measurement gap for the new GNSS measurement. For example, in response to the NE receiving the UE triggering at 303, the method may include deciding, based on the triggering information from the UE, to schedule and transmit a new GNSS measurement to the UE (e.g., DL PDCCH/PDSCH) .

FIG. 4 illustrates an example of a system according to certain example embodiments. In one example embodiment, a system may include multiple devices, such as, for example, NE 410 and/or UE 420.

NE 410 may be one or more of a base station (e.g., 3G UMTS NodeB, 4G LTE Evolved NodeB, or 5G NR Next Generation NodeB) , a serving gateway, a server, and/or any other access node or combination thereof.

NE 410 may further comprise at least one gNB-centralized unit (CU) , which may be associated with at least one gNB-distributed unit (DU) . The at least one gNB-CU and the at least one gNB-DU may be in communication via at least one F1 interface, at least one X _n-C interface, and/or at least one NG interface via a 5 ^th generation core (5GC) .

UE 420 may include one or more of a mobile device, such as a mobile phone, smart phone, personal digital assistant (PDA) , tablet, or portable media player, digital camera, pocket video camera, video game console, navigation unit, such as a global positioning system (GPS) device, desktop or laptop computer, single-location device, such as a sensor or smart meter, or any combination thereof. Furthermore, NE 410 and/or UE 420 may be one or more of a citizens broadband radio service device (CBSD) .

NE 410 and/or UE 420 may include at least one processor, respectively indicated as 411 and 421.

Processors

411 and 421 may be embodied by any computational or data processing device, such as a central processing unit (CPU) , application specific integrated circuit (ASIC) , or comparable device. The processors may be implemented as a single controller, or a plurality of controllers or processors.

At least one memory may be provided in one or more of the devices, as indicated at 412 and 422. The memory may be fixed or removable. The memory may include computer program instructions or computer code contained therein.

Memories

412 and 422 may independently be any suitable storage device, such as a non-transitory computer-readable medium. The term “non-transitory, ” as used herein, may correspond to a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., random access memory (RAM) vs. read-only memory (ROM) ) . A hard disk drive (HDD) , random access memory (RAM) , flash memory, or other suitable memory may be used. The memories may be combined on a single integrated circuit as the processor, or may be separate from the one or more processors. Furthermore, the computer program instructions stored in the memory, and which may be processed by the processors, may be any suitable form of computer program code, for example, a compiled or interpreted computer program written in any suitable programming language.

Processors

411 and 421,

memories

412 and 422, and any subset thereof, may be configured to provide means corresponding to the various blocks of FIGs. 1-3. Although not shown, the devices may also include positioning hardware, such as GPS or micro electrical mechanical system (MEMS) hardware, which may be used to determine a location of the device. Other sensors are also permitted, and may be configured to determine location, elevation, velocity, orientation, and so forth, such as barometers, compasses, and the like.

As shown in FIG. 4,

transceivers

413 and 423 may be provided, and one or more devices may also include at least one antenna, respectively illustrated as 414 and 424. The device may have many antennas, such as an array of antennas configured for multiple input multiple output (MIMO) communications, or multiple antennas for multiple RATs. Other configurations of these devices, for example, may be provided.

Transceivers

413 and 423 may be a transmitter, a receiver, both a transmitter and a receiver, or a unit or device that may be configured both for transmission and reception.

The memory and the computer program instructions may be configured, with the processor for the particular device, to cause a hardware apparatus, such as UE, to perform any of the processes described above (i.e., FIGs. 1-3) . Therefore, in certain example embodiments, a non-transitory computer-readable medium may be encoded with computer instructions that, when executed in hardware, perform a process such as one of the processes described herein. Alternatively, certain example embodiments may be performed entirely in hardware.

In certain example embodiments, an apparatus may include circuitry configured to perform any of the processes or functions illustrated in FIGs. 1-3. As used in this application, the term “circuitry” may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) , (b) combinations of hardware circuits and software, such as (as applicable) : (i) a combination of analog and/or digital hardware circuit (s) with software/firmware and (ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) , and (c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation. This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

FIG. 5 illustrates an example of a 5G network and system architecture according to certain example embodiments. Shown are multiple network functions that may be implemented as software operating as part of a network device or dedicated hardware, as a network device itself or dedicated hardware, or as a virtual function operating as a network device or dedicated hardware. The NE and UE illustrated in FIG. 5 may be similar to NE 410 and UE 420, respectively. The user plane function (UPF) may provide services such as intra-RAT and inter-RAT mobility, routing and forwarding of data packets, inspection of packets, user plane quality of service (QoS) processing, buffering of DL packets, and/or triggering of DL data notifications. The application function (AF) may primarily interface with the core network to facilitate application usage of traffic routing and interact with the policy framework.

According to certain example embodiments,

processors

411 and 421, and

memories

412 and 422, may be included in or may form a part of processing circuitry or control circuitry. In addition, in some example embodiments,

transceivers

413 and 423 may be included in or may form a part of transceiving circuitry.

In some example embodiments, an apparatus (e.g., NE 410 and/or UE 420) may include means for performing a method, a process, or any of the variants discussed herein. Examples of the means may include one or more processors, memory, controllers, transmitters, receivers, and/or computer program code for causing the performance of the operations.

In various example embodiments, apparatus 420 may be controlled by memory 422 and processor 421 to estimate at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal; determine that at least one of the downlink time error or downlink frequency error is larger than a threshold; and transmit, to a network entity, an indication of global navigation satellite system (GNSS) related information.

Certain example embodiments may be directed to an apparatus that includes means for performing any of the methods described herein including, for example, means for estimating at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal; means for determining that at least one of the downlink time error or downlink frequency error is larger than a threshold; and means for transmitting, to a network entity, an indication of global navigation satellite system (GNSS) related information.

In various example embodiments, apparatus 410 may be controlled by memory 412 and processor 411 to receive, from a user equipment, an indication of global navigation satellite system (GNSS) related information; and determine that the user equipment has GNSS information based on the indication of GNSS related information.

Certain example embodiments may be directed to an apparatus that includes means for performing any of the methods described herein including, for example, means for receiving, from a user equipment, an indication of global navigation satellite system (GNSS) related information; and means for determining that the user equipment has GNSS information based on the indication of GNSS related information.

The features, structures, or characteristics of example embodiments described throughout this specification may be combined in any suitable manner in one or more example embodiments. For example, the usage of the phrases “various embodiments, ” “certain embodiments, ” “some embodiments, ” or other similar language throughout this specification refers to the fact that a particular feature, structure, or characteristic described in connection with an example embodiment may be included in at least one example embodiment. Thus, appearances of the phrases “in various embodiments, ” “in certain embodiments, ” “in some embodiments, ” or other similar language throughout this specification does not necessarily all refer to the same group of example embodiments, and the described features, structures, or characteristics may be combined in any suitable manner in one or more example embodiments.

As used herein, “at least one of the following: <a list of two or more elements>” and “at least one of <a list of two or more elements>” and similar wording, where the list of two or more elements are joined by “and” or “or, ” mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

Additionally, if desired, the different functions or procedures discussed above may be performed in a different order and/or concurrently with each other. Furthermore, if desired, one or more of the described functions or procedures may be optional or may be combined. As such, the description above should be considered as illustrative of the principles and teachings of certain example embodiments, and not in limitation thereof.

One having ordinary skill in the art will readily understand that the example embodiments discussed above may be practiced with procedures in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although some embodiments have been described based upon these example embodiments, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the spirit and scope of the example embodiments.

Partial Glossary

3GPP 3 ^rd Generation Partnership Project

5G 5 ^th Generation

5GC 5 ^th Generation Core

6G 6 ^th Generation

AF Application Function

ASIC Application Specific Integrated Circuit

CBSD Citizens Broadband Radio Service Device

CPU Central Processing Unit

CU Centralized Unit

DL Downlink

DMRS Demodulation Reference Signal

DU Distributed Unit

eMBB Enhanced Mobile Broadband

eMTC Enhanced Machine Type Communication

eNB Evolved Node B

gNB Next Generation Node B

GNSS Global Navigation Satellite System

GPS Global Positioning System

HDD Hard Disk Drive

IoT Internet of Things

LTE Long-Term Evolution

LTE-A Long-Term Evolution Advanced

MEMS Micro Electrical Mechanical System

MIB Master Information Block

MIMO Multiple Input Multiple Output

mMTC Massive Machine Type Communication

NE Network Entity

NG Next Generation

NG-eNB Next Generation Evolved Node B

NG-RAN Next Generation Radio Access Network

NPRS Narrowband Positioning Reference Signal

NR New Radio

NRS Narrowband Reference Signal

NTN Non-Terrestrial Network

PBCH Physical Broadcast Channel

PDA Personal Digital Assistance

PDSCH Physical Downlink Shared Channel

PN Pseudo-Random/Pseudo-Noise

PRACH Physical Random Access Channel

PRB Physical Resource Block

PRS Positioning Reference Signal

PSS Primary Synchronization Signal

QoS Quality of Service

RAM Random Access Memory

RAN Radio Access Network

RAT Radio Access Technology

RF Radio Frequency

ROM Read-Only Memory

RRC Radio Resource Control

RSS Resynchronization Signal

SFN System Frame Number

SSS Secondary Synchronization Signal

T/F Time/Frequency

UE User Equipment

UL Uplink

UMTS Universal Mobile Telecommunications System

UPF User Plane Function

URLLC Ultra-Reliable and Low-Latency Communication

UTRAN Universal Mobile Telecommunications System Terrestrial Radio Access Network

Claims

An apparatus comprising:

at least one processor; and

at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to:

estimate at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal;

determine that at least one of the downlink time error or downlink frequency error is larger than a threshold; and

transmit, to a network entity, an indication of global navigation satellite system (GNSS) related information.
The apparatus of claim 1, wherein the at least one downlink receiving signal comprises a synchronization signal.
The apparatus of claim 1 or 2, wherein the indication of GNSS related information comprises a physical random access channel.
The apparatus of any of claims 1-3, wherein the indication of GNSS related information is configured to trigger at least one of a location measurement or GNSS measurement.
The apparatus of any of claims 1-4, wherein the at least one memory and the instructions, when executed by the at least one processor, further cause the apparatus at least to:

receive, from the network entity, a configuration to initiate an estimation of at least one of the downlink time error or downlink frequency error in a time duration for triggering location measurements.
The apparatus of any of claims 1-5, wherein at least one of the downlink time error or downlink frequency error comprises an error of at least one of predicted receiving time or predicted receiving frequency of a downlink signal compared with at least one of a time or frequency of the at least one downlink receiving signal.
The apparatus of any of claims 1-6, wherein at least one of the downlink time error or downlink frequency error is based on at least one of a latest measured GNSS location or a latest received satellite assistance information.
The apparatus of any of claims 1-7, wherein the at least one memory and the instructions, when executed by the at least one processor, further cause the apparatus at least to:

receive, from the network entity, at least one of a configuration of the estimation, a configuration of resources to transmit the indication of GNSS, the threshold, or a time to start the estimation.
The apparatus of claim 8, wherein the time to start the estimation comprises:

a time since a last uplink transmission that exceeds a second threshold; or

a time until a GNSS validity duration expiry that is less than a third threshold.
The apparatus of any of claims 1-9, wherein the GNSS related information comprises at least one of the following:

an indication of whether a new GNSS measurement is needed;

a magnitude of at least one of the downlink time error or downlink frequency error;

detected movement of the apparatus;

a distance that the apparatus has moved;

whether the apparatus needs more or less time for a GNSS measurement than a previously reported time requested; or

how much time the apparatus needs for a GNSS measurement than a previously reported time requested.
The apparatus of any of claims 1-10, wherein the at least one memory and the instructions, when executed by the at least one processor, further cause the apparatus at least to:

after the apparatus transmits the indication of GNSS related information, starting reacquiring of the GNSS.
The apparatus of any of claims 1-11, wherein the configuration to initiate an estimation enables the apparatus to trigger at least one of a new GNSS measurement or time/frequency resources for transmission of the synchronization signal.
An apparatus comprising:

at least one processor; and

at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to:

receive, from a user equipment, an indication of global navigation satellite system (GNSS) related information; and

determine that the user equipment has GNSS information based on the indication of GNSS related information.
The apparatus of claim 13, wherein the indication of GNSS related information is based at least in part on an estimation by the user equipment of at least one of a downlink time error or downlink frequency error associated with at least one downlink receiving signal.
The apparatus of claim 13 or 14, wherein the at least one downlink receiving signal comprises a synchronization signal.
The apparatus of any of claims 13-15, wherein the indication of GNSS related information comprises a physical random access channel.
The apparatus of any of claims 13-16, wherein the indication of GNSS related information is configured to trigger at least one of a location measurement or GNSS measurement.
The apparatus of any of claims 13-17, wherein the at least one memory and the instructions, when executed by the at least one processor, further cause the apparatus at least to:

transmit, to the user equipment, a configuration to initiate an estimation of at least one of the downlink time error or downlink frequency error in a time duration for triggering location measurements.
The apparatus of claim 18, wherein the configuration to initiate an estimation is transmitted after the apparatus has not received an uplink transmission within a predetermined duration of time.
The apparatus of any of claims 13-19, wherein at least one of the downlink time error or downlink frequency error comprises an error of at least one of predicted receiving time or predicted receiving frequency of a downlink signal compared with at least one of a time or frequency of the at least one downlink receiving signal.
The apparatus of any of claims 13-20, wherein at least one of the downlink time error or downlink frequency error is based on at least one of a latest measured GNSS location or a latest received satellite assistance information.
The apparatus of any of claims 13-21, wherein the at least one memory and the instructions, when executed by the at least one processor, further cause the apparatus at least to:

transmit, to the user equipment, at least one of a configuration of the estimation, a configuration of resources to transmit the indication of GNSS, the threshold, or a time to start the estimation.
The apparatus of claim 22, wherein the time to start the estimation comprises:

a time since a last uplink transmission that exceeds a second threshold; or

a time until a GNSS validity duration expiry that is less than a third threshold.
The apparatus of any of claims 13-23, wherein the GNSS related information comprises at least one of the following:

an indication of whether a new GNSS measurement is needed;

a magnitude of at least one of the downlink time error or downlink frequency error;

detected movement of the apparatus;

a distance that the apparatus has moved;

whether the apparatus needs more or less time for a GNSS measurement than a previously reported time requested; or

how much time the apparatus needs for a GNSS measurement than a previously reported time requested.
The apparatus of any of claims 13-24 wherein the configuration to initiate an estimation enables the apparatus to trigger at least one of a new GNSS measurement or time/frequency resources for transmission of the synchronization signal.
An apparatus comprising:

means for estimating at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal;

means for determining that at least one of the downlink time error or downlink frequency error is larger than a threshold; and

means for transmitting, to a network entity, an indication of global navigation satellite system (GNSS) related information.
The apparatus of claim 26, wherein the at least one downlink receiving signal comprises a synchronization signal.
The apparatus of claim 26 or 27, wherein the indication of GNSS related information comprises a physical random access channel.
The apparatus of any of claims 26-28, wherein the indication of GNSS related information is configured to trigger at least one of a location measurement or GNSS measurement.
The apparatus of any of claims 26-29, further comprising:

means for receiving, from the network entity, a configuration to initiate an estimation of at least one of the downlink time error or downlink frequency error in a time duration for triggering location measurements.
The apparatus of any of claims 26-30, wherein at least one of the downlink time error or downlink frequency error comprises an error of at least one of predicted receiving time or predicted receiving frequency of a downlink signal compared with at least one of a time or frequency of the at least one downlink receiving signal.
The apparatus of any of claims 26-31, wherein at least one of the downlink time error or downlink frequency error is based on at least one of a latest measured GNSS location or a latest received satellite assistance information.
The apparatus of any of claims 26-32, further comprising:

means for receiving, from the network entity, at least one of a configuration of the estimation, a configuration of resources to transmit the indication of GNSS, the threshold, or a time to start the estimation.
The apparatus of claim 33, wherein the time to start the estimation comprises:

a time since a last uplink transmission that exceeds a second threshold; or

a time until a GNSS validity duration expiry that is less than a third threshold.
The apparatus of any of claims 26-34, wherein the GNSS related information comprises at least one of the following:

an indication of whether a new GNSS measurement is needed;

a magnitude of at least one of the downlink time error or downlink frequency error;

detected movement of the apparatus;

a distance that the apparatus has moved;

whether the apparatus needs more or less time for a GNSS measurement than a previously reported time requested; or

how much time the apparatus needs for a GNSS measurement than a previously reported time requested.
The apparatus of any of claims 26-35, further comprising:

means for starting reacquiring of the GNSS after the apparatus transmits the indication of GNSS related information.
The apparatus of any of claims 26-36, wherein the configuration to initiate an estimation enables the apparatus to trigger at least one of a new GNSS measurement or time/frequency resources for transmission of the synchronization signal.
An apparatus comprising:

means for receiving, from a user equipment, an indication of global navigation satellite system (GNSS) related information; and

means for determining that the user equipment has GNSS information based on the indication of GNSS related information.
The apparatus of claim 38, wherein the indication of GNSS related information is based at least in part on an estimation by the user equipment of at least one of a downlink time error or downlink frequency error associated with at least one downlink receiving signal.
The apparatus of claim 38 or 39, wherein the at least one downlink receiving signal comprises a synchronization signal.
The apparatus of any of claims 38-40, wherein the indication of GNSS related information comprises a physical random access channel.
The apparatus of any of claims 38-41, wherein the indication of GNSS related information is configured to trigger at least one of a location measurement or GNSS measurement.
The apparatus of any of claims 38-42, further comprising:

means for transmitting, to the user equipment, a configuration to initiate an estimation of at least one of the downlink time error or downlink frequency error in a time duration for triggering location measurements.
The apparatus of claim 43, wherein the configuration to initiate an estimation is transmitted after the apparatus has not received an uplink transmission within a predetermined duration of time.
The apparatus of any of claims 38-44, wherein at least one of the downlink time error or downlink frequency error comprises an error of at least one of predicted receiving time or predicted receiving frequency of a downlink signal compared with at least one of a time or frequency of the at least one downlink receiving signal.
The apparatus of any of claims 38-45, wherein at least one of the downlink time error or downlink frequency error is based on at least one of a latest measured GNSS location or a latest received satellite assistance information.
The apparatus of any of claims 38-46, further comprising:

means for transmitting, to the user equipment, at least one of a configuration of the estimation, a configuration of resources to transmit the indication of GNSS, the threshold, or a time to start the estimation.
The apparatus of claim 47, wherein the time to start the estimation comprises:

a time since a last uplink transmission that exceeds a second threshold; or

a time until a GNSS validity duration expiry that is less than a third threshold.
The apparatus of any of claims 38-48, wherein the GNSS related information comprises at least one of the following:

an indication of whether a new GNSS measurement is needed;

a magnitude of at least one of the downlink time error or downlink frequency error;

detected movement of the apparatus;

a distance that the apparatus has moved;

whether the apparatus needs more or less time for a GNSS measurement than a previously reported time requested; or

how much time the apparatus needs for a GNSS measurement than a previously reported time requested.
The apparatus of any of claims 38-49, wherein the configuration to initiate an estimation enables the apparatus to trigger at least one of a new GNSS measurement or time/frequency resources for transmission of the synchronization signal.
A method comprising:

estimating, by a user equipment, at least one of a downlink time error or downlink frequency error by measuring at least one downlink receiving signal;

determining that at least one of the downlink time error or downlink frequency error is larger than a threshold; and

transmitting, to a network entity, an indication of global navigation satellite system (GNSS) related information.
The method of claim 51, wherein the at least one downlink receiving signal comprises a synchronization signal.
The method of claim 51 or 52, wherein the indication of GNSS related information comprises a physical random access channel.
The method of any of claims 51-53, wherein the indication of GNSS related information is configured to trigger at least one of a location measurement or GNSS measurement.
The method of any of claims 51-54, further comprising:

receiving, from the network entity, a configuration to initiate an estimation of at least one of the downlink time error or downlink frequency error in a time duration for triggering location measurements.
The method of any of claims 51-55, wherein at least one of the downlink time error or downlink frequency error comprises an error of at least one of predicted receiving time or predicted receiving frequency of a downlink signal compared with at least one of a time or frequency of the at least one downlink receiving signal.
The method of any of claims 51-56, wherein at least one of the downlink time error or downlink frequency error is based on at least one of a latest measured GNSS location or a latest received satellite assistance information.
The method of any of claims 51-57, further comprising:

receiving, from the network entity, at least one of a configuration of the estimation, a configuration of resources to transmit the indication of GNSS, the threshold, or a time to start the estimation.
The method of claim 58, wherein the time to start the estimation comprises:

a time since a last uplink transmission that exceeds a second threshold; or

a time until a GNSS validity duration expiry that is less than a third threshold.
The method of any of claims 51-59, wherein the GNSS related information comprises at least one of the following:

an indication of whether a new GNSS measurement is needed;

a magnitude of at least one of the downlink time error or downlink frequency error;

detected movement of the user equipment;

a distance that the user equipment has moved;

whether the user equipment needs more or less time for a GNSS measurement than a previously reported time requested; or

how much time the user equipment needs for a GNSS measurement than a previously reported time requested.
The method of any of claims 51-60, further comprising:

starting reacquiring of the GNSS after the user equipment transmits the indication of GNSS related information.
The method of any of claims 51-61, wherein the configuration to initiate an estimation enables the user equipment to trigger at least one of a new GNSS measurement or time/frequency resources for transmission of the synchronization signal.
A method comprising:

receiving, by a network entity, from a user equipment, an indication of global navigation satellite system (GNSS) related information; and

determining that the user equipment has GNSS information based on the indication of GNSS related information.
The method of claim 63, wherein the indication of GNSS related information is based at least in part on an estimation by the user equipment of at least one of a downlink time error or downlink frequency error associated with at least one downlink receiving signal.
The method of claim 63 or 64, wherein the at least one downlink receiving signal comprises a synchronization signal.
The method of any of claims 63-65, wherein the indication of GNSS related information comprises a physical random access channel.
The method of any of claims 63-66, wherein the indication of GNSS related information is configured to trigger at least one of a location measurement or GNSS measurement.
The method of any of claims 63-67, further comprising:

transmitting, to the user equipment, a configuration to initiate an estimation of at least one of the downlink time error or downlink frequency error in a time duration for triggering location measurements.
The method of claim 68, wherein the configuration to initiate an estimation is transmitted after the network entity has not received an uplink transmission within a predetermined duration of time.
The method of any of claims 63-69, wherein at least one of the downlink time error or downlink frequency error comprises an error of at least one of predicted receiving time or predicted receiving frequency of a downlink signal compared with at least one of a time or frequency of the at least one downlink receiving signal.
The method of any of claims 63-70, wherein at least one of the downlink time error or downlink frequency error is based on at least one of a latest measured GNSS location or a latest received satellite assistance information.
The method of any of claims 63-71, further comprising:

transmitting, to the user equipment, at least one of a configuration of the estimation, a configuration of resources to transmit the indication of GNSS, the threshold, or a time to start the estimation.
The method of claim 72, wherein the time to start the estimation comprises:

a time since a last uplink transmission that exceeds a second threshold; or

a time until a GNSS validity duration expiry that is less than a third threshold.
The method of any of claims 63-73, wherein the GNSS related information comprises at least one of the following:

an indication of whether a new GNSS measurement is needed;

a magnitude of at least one of the downlink time error or downlink frequency error;

detected movement of the user equipment;

a distance that the user equipment has moved;

whether the user equipment needs more or less time for a GNSS measurement than a previously reported time requested; or

how much time the user equipment needs for a GNSS measurement than a previously reported time requested.
The method of any of claims 63-74, wherein the configuration to initiate an estimation enables the user equipment to trigger at least one of a new GNSS measurement or time/frequency resources for transmission of the synchronization signal.
A non-transitory computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to perform at least a method according to any of claims 51-75.
An apparatus comprising circuitry configured to perform a method according to any of claims 51-75.
A computer program comprising instructions, which, when executed by an apparatus, cause the apparatus to perform the method of any of claims 51-75.