WO2021089906A1 - Enhancement on provision of timing advance data - Google Patents

Abstract

A method may include receiving, at a user equipment, a broadcast including network range markers data from a network element. The method may also include performing a distance measurement of the user equipment to the network element. The method may further include determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located.

Description

TITLE:

ENHANCEMENT ON PROVISION OF TIMING ADVANCE DATA

CROSS-REFERENCE TO RELATED APPLICATIONS: This application claims priority from U.S. provisional patent application no. 62/930,909 filed on November 5, 2019. The contents of this earlier filed application are hereby incorporated by reference in their entirety

FIELD: Some example embodiments may generally relate to mobile or wireless telecommunication systems, such as Long Term Evolution (LTE) or fifth generation (5G) radio access technology or new radio (NR) access technology, or other communications systems. For example, certain embodiments may relate to apparatuses, systems, and/or methods for enhancing provision of timing advance data.

BACKGROUND:

Examples of mobile or wireless telecommunication systems may include the Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN), Long Term Evolution (LTE) Evolved UTRAN (E-UTRAN), LTE- Advanced (LTE- A), MulteFire, LTE-A Pro, and/or fifth generation (5G) radio access technology or new radio (NR) access technology. Fifth generation (5G) wireless systems refer to the next generation (NG) of radio systems and network architecture. 5G is mostly built on a new radio (NR), but the 5G (or NG) network can also build on E- UTRAN radio. It is estimated that NR will provide bitrates on the order of 10-20 Gbit/s or higher, and will support at least enhanced mobile broadband (eMBB) and ultra reliable low-latency-communication (URLLC) as well as massive machine type communication (mMTC). NR is expected to deliver extreme broadband and ultra- robust, low latency connectivity and massive networking to support the Internet of Things (IoT). With IoT and machine-to-machine (M2M) communication becoming more widespread, there will be a growing need for networks that meet the needs of lower power, low data rate, and long battery life. It is noted that, in 5G, the nodes that can provide radio access functionality to a user equipment (i.e., similar to Node B in UTRAN or eNB in LTE) are named gNB when built on NR radio and named NG-eNB when built on E-UTRAN radio.

SUMMARY:

Some example embodiments are directed to a method. The method may include receiving, at a user equipment, a broadcast including network range markers data from a network element. The method may also include performing a distance measurement of the user equipment to the network element. The method may further include determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located.

Other example embodiments may be directed to an apparatus. The apparatus may include at least one processor and at least one memory including computer program code. The at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus at least to receive a broadcast including network range markers data from a network element. The apparatus may also be caused to perform a distance measurement of the apparatus to the network element. The apparatus may further be caused to determine, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the apparatus is located. Other example embodiments may be directed to an apparatus. The apparatus may include means for receiving a broadcast including network range markers data from a network element. The apparatus may also include means for performing a distance measurement of the user equipment to the network element. The apparatus may further include means for determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located.

In accordance with other example embodiments, a non-transitory computer readable medium may be encoded with instmctions that may, when executed in hardware, perform a method. The method may include receiving, at a user equipment, a broadcast including network range markers data from a network element. The method may also include performing a distance measurement of the user equipment to the network element. The method may further include determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located.

Other example embodiments may be directed to a computer program product that performs a method. The method may include receiving, at a user equipment, a broadcast including network range markers data from a network element. The method may also include performing a distance measurement of the user equipment to the network element. The method may further include determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located.

Other example embodiments may be directed to an apparatus that may include circuitry configured to receive a broadcast including network range markers data from a network element. The apparatus may also include circuitry configured to perform a distance measurement of the apparatus to the network element. The apparatus may further include circuitry configured to determine, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the apparatus is located.

Certain example embodiments may be directed to a method. The method may include determining, by a network element, network range markers data which partitions a cell coverage into sectors. The method may also include calculating a timing advance value for a user equipment. The method may further include determining a timing advance index value based on the calculated timing advance value and the network range markers data. In addition, the method may include sending the timing advance index value to the user equipment. Other example embodiments may be directed to an apparatus. The apparatus may include at least one processor and at least one memory including computer program code. The at least one memory and computer program code may be configured to, with the at least one processor, cause the apparatus at least to determine network range markers data which partitions a cell coverage into sectors. The apparatus may also be caused to calculate a timing advance value for a user equipment. The apparatus may further be caused to determine a timing advance index value based on the calculated timing advance value and the network range markers data. In addition, the apparatus may be caused to send the timing advance index value to the user equipment.

Other example embodiments may be directed to an apparatus. The apparatus may include means for determining network range markers data which partitions a cell coverage into sectors. The apparatus may also include means for calculating a timing advance value for a user equipment. The apparatus may further include means for determining a timing advance index value based on the calculated timing advance value and the network range markers data. In addition, the apparatus may include means for sending the timing advance index value to the user equipment.

In accordance with other example embodiments, a non-transitory computer readable medium may be encoded with instructions that may, when executed in hardware, perform a method. The method may include determining, by a network element, network range markers data which partitions a cell coverage into sectors. The method may also include calculating a timing advance value for a user equipment. The method may further include determining a timing advance index value based on the calculated timing advance value and the network range markers data. In addition, the method may include sending the timing advance index value to the user equipment.

Other example embodiments may be directed to a computer program product that performs a method. The method may include determining, by a network element, network range markers data which partitions a cell coverage into sectors. The method may also include calculating a timing advance value for a user equipment. The method may further include determining a timing advance index value based on the calculated timing advance value and the network range markers data. In addition, the method may include sending the timing advance index value to the user equipment.

Other example embodiments may be directed to an apparatus that may include circuitry configured to determine network range markers data which partitions a cell coverage into sectors. The apparatus may also include circuitry configured to calculate a timing advance value for a user equipment. The apparatus may further include circuitry configured to determine a timing advance index value based on the calculated timing advance value and the network range markers data. In addition, the apparatus may include circuitry configured to send the timing advance index value to the user equipment. BRIEF DESCRIPTION OF THE DRAWINGS :

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

FIG. 1, which illustrates uplink to downlink timing adjustment principles.

FIG. 2 illustrates a scenario with three user equipments at different distances within a cell, according to an example embodiment.

FIG. 3 illustrates certain values for the scenario illustrated in FIG. 2, according to an example embodiment.

FIG. 4 illustrates a global positioning system-based timing advance, according to an example embodiment. FIG. 5 illustrates a scenario with three user equipments at different distances within the cell, according to an example embodiment.

FIG. 6 illustrates timing advance index values provided by the eNB for three exemplary user equipments, according to an example embodiment.

FIG. 7 illustrates an unambiguity sector selection, according to an example embodiment. FIG. 8 illustrates a signaling diagram of timing advance resolution enhancement with time of arrival-based verification, according to an example embodiment.

FIG. 9 illustrates timing advance resolution enhancement in non- terrestrial network, according to an example embodiment.

FIG. 10 illustrates a flow diagram of a method, according to an example embodiment. FIG. 11 illustrates a flow diagram of another method, according to an example embodiment.

FIG. 12(a) illustrates an apparatus, according to an example embodiment.

FIG. 12(b) illustrates another apparatus, according to an example embodiment.

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. The following is a detailed description of some example embodiments of systems, methods, apparatuses, and computer program products for enhancing provision of timing advance data.

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 “certain embodiments,” “an example embodiment,” “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 embodiment may be included in at least one embodiment. Thus, appearances of the phrases “in certain embodiments,” “an example embodiment,” “in some embodiments,” “in other embodiments,” or other similar language, throughout this specification do not necessarily all refer to the same group of embodiments, and the described features, structures, or characteristics may be combined in any suitable manner in one or more example embodiments. Additionally, if desired, the different functions or steps discussed below may be performed in a different order and/or concurrently with each other. Furthermore, if desired, one or more of the described functions or steps may be optional or may be combined. As such, the following description should be considered as merely illustrative of the principles and teachings of certain example embodiments, and not in limitation thereof.

Timing Advance based method may be utilized for uplink (UL) channel synchronization. 3^rd Generation Partnership Project (3GPP) technical specifications (TS) have described timing adjustment principles and physical random access channel (PRACH) preambles. These TS may include, for example, 3GPP TS 36.213 or TS 36.211. Further, the user equipment (UE) UL channel synchronization and maintenance may be enabled by a timing advance (TA) command. For example, the TA command may be in the form of Eq. 1 shown below.

N_XA = T_A * 16 * T_s [Eq. 1]

As shown in Eq. 1, T_A may represent a timing advance index value provided by the eNB, and may be in the form of 11-bits. In addition, Ts may represent a basic time unit, and N_TA may represent an UL timing adjustment.

In a medium access control (MAC) control element (CE) update for UE mobility handling, the following Eq. 2 may be provided.

NTA_, new

[Eq. 2]

As shown in Eq. 2, T_A may represent 6-bits (0, ..., 63), NTA, n_ew may represent a new timing adjustment value, and NTA, _ol_d may represent a current timing adjustment. The TA value may be provided by the eNB in MAC CE TA update. FIG. 1 illustrates UL to downlink (DL) timing adjustment principles. In particular, the UL to DL timing adjustment principles may be according to 3GPP TS 36.211. As illustrated in FIG. 1 , a DL radio frame i may be offset from an UL radio frame / by {NTA + NTA offset) * 7s seconds. In an example embodiment, based on TOA principles, a propagation delay distance between the UE and the eNB, D(Ts), may be calculated using Eq. 3 shown below.

D(T_S) = c » (Ti(Ts) - T„(Ts)) [m] [Eq. 3]

In Eq. 3, To may represent a reference signal physical transmission time by the eNB, Ti may represent a reference signal reception time by the UE, c may represent the speed of light, Ts may represent a basic time unit and which measurement defines accuracy, and D(Ts) may represent a signal propagation delay distance.

In an example embodiment, the distance D(Ts) may be expressed in the form of an index value TA_d(Ts), as shown in Eq. 4 below.

TA_d(T_s) = int [Eq. 4]

In Eq. 4, D(Ts) may represent a signal propagation delay distance, IT_A may represent 78 meters (m), minimal step, and TA_d(Ts) may represent a TOA-based equivalent of the TA index value.

In certain example embodiments, the TA command may indicate the change of the UL timing relative to the currently UL timing as multiples of 16*Ts, which may be the current minimal TA step, and may correspond to a distance of 78 m, as shown by Eq. 5 below. In Eq. 5, Ts may represent a basic time unit.

1T_A = 16 * T_s = 78 m [Eq. 5] With the TA command of Eq. 5, there may be a challenge of a trade off between sufficient timing accuracy and required signaling word length (TA Command, 11-bits) in a given maximum cell range. Further, more accurate UL to DL timing adjustment may improve the quality of signal detection. In one application, this may be limited by a I TA resolution.

Another challenge may be that the TA related word length of 11 -bits for the TA command and 6-bits for MAC CE TA update may unambiguously address TA correction within a defined maximum range. In an example embodiment, to unambiguously address the TA correction may mean that the given TA value provided by the eNB may be unique for the given UE distance. For instance, no other TA value may be used to provide the required TA for the UE at the given distance from the eNB. For this purpose, 11-bits word length is needed for a 100 km cell radius. In one example embodiment, the defined maximum range may be approximately 100 km for TA command and 5 km for MAC CE update. This may limit the maximum cell range, where the eNB may provide unambiguous information about TA. However, as discussed herein, certain example embodiments may use shorter TA word length for the same coverage. Although this may create some ambiguity, as the same TA value may address two or more distances, certain example embodiments may provide independent TOA measurements to be used, and a combination of these two values may provide an unambiguous value for TA.

FIG. 2 illustrates a scenario with three UEs at different distances within a cell, according to an example embodiment. As illustrated in FIG. 2, the eNB may provide omnidirectional coverage, and may be divided on three (3) 120-degree cells. In certain example embodiments, a total cell range may be from R_min = 0 to R_max = 100 km (values may have illustrative character). Further, a maximum TA index value may be 1282, such as, for example, 1282*78 m = 99,996 m, where ITA = 78 m, which may be a current minimal TA step used as a reference value. According to certain example embodiments, the UEs may support TOA-based measurement, and may report TOA-based distance D(Ts) to the eNB. As illustrated in the example of FIG. 2, there may be three UEs including, for example, UE1 (TA = 473; D(Ts) = 36.9 km), UE 2 (TA = 670; D(T_S) = 52.3 km), and UE 3 (TA = 1,114; D(T_S) = 86.9 km). The three UEs may be detected by the eNB at various TA values for which the UEs may also measure TOA distances D(Ts) with a measurement accuracy of Ts. It should be noted that example embodiments are not just limited to these UEs, as a number of UEs may be included according to other example embodiments.

FIG. 3 illustrates certain values for the scenario illustrated in FIG. 2, according to an example embodiment. In particular, FIG. 3 illustrates TA steps and TOA measurements with respect to distance. According to an example embodiment, an 11 -bits TA Command may be used during a random access response (RAR) and may be used for uplink timing adjustment by the UE. [Eq. 1], and then 6-bits MAC CE TA update mechanism, [Eq. 2] may be applied for continuous UL to DL channel synchronization.

In certain example embodiments, the potential TA resolution may have the following considerations: 11-bits word length (i.e., 10100000010 (bit) is 1282; if 99996 km is divided by 1282, we my have step 78 m, which is a legacy solution); 11-bits word length (i.e., 11111111111 (bit) is 2047; if 99996 km is divided by 2047, we may have step 48.85 m, which is the maximum resolution for 11-bits word length); 12-bits word length (i.e., 111111111111 (bit) is 4095; if 99996 km divides by 4095, we may have step 24.42 m, which is the maximum resolution for 12-bits word length); 15-bits word length (i.e., 101000000100000 (bit) is 20512; if 9996 is divided by 20512, we may have step 4.875 m (Ts), which is the maximum resolution for 15-bits word length.

As shown from the above considerations, for the same maximum cell range, improved accuracy of the TA index value may require longer bit word length, which may further require additional radio resources for signaling. Further, the eNB may be able to determine TA with resolution of basic time unit Ts, but as a compromise between accuracy and signaling bit word length, minimum step 16*Ts may be used for TA. Additionally, an extension of required TA-related word length may not be considered as a desirable solution as it may require more signaling data over radio interface. Another challenge may be related to usage of global positioning system (GPS) positioning data to determine initial or dedicated TA correction, especially in non terrestrial network (NTN) applications.

FIG. 4 illustrates a GPS-based TA, according to an example embodiment. In particular, as illustrated in FIG. 4, it may be assumed that GPS or other satellite -based positioning system may be used to determine the position of the eNB, the eNB NTN, and the UE. Based on these data, the eNB based on received UE position may determine a geometric distance between the eNB and the UE. This may be denoted as Do, where Do may be considered as direct line of sight distance. Further, in normal circumstances, Do may correspond to the microwave signal path, which means that it may also correspond to the TA value in the RRC connection.

However, in some cases, the RRC connection may be established by multipath propagation or a reflected signal may be used. For example, a microwave signal may travel a distance Di + ZU, which may be longer than Do- In an example embodiment, for an RRC connection, this may not be a problem as TA calculation may reflect a true path, which in this case, may be Di + D2. Further, this may be a common behavior for a ground-based eNB and NTN. In addition, in certain example embodiments, the eNB may have no information about the selected path, as this may be determined by the UE measurements.

Establishment of the RRC connection described above may lead to errors if position- based distance is compared to reflected signal path distance, especially if a difference is significantly higher than 1TA minimal distance. This may be, for instance, 78 m for LTE. Thus, in this situation, the UE may be provided with inaccurate TA correction, or such method may provide only a rough TA estimation. Furthermore, the legacy TA method is specified in related 3GPP standards, which may define a current solution used for UL channel synchronization. For instance, in NTN, by using GPS positioning of the UE, it may be possible to provide initial TA for the UE. However, the UE may need to report its position to the eNB.

According to certain example embodiments, the UE UL channel timing adjustment in the entire cell range may be maintained by one, unambiguous TA index value provided by the eNB, which may have a resolution defined by Eq. 5. Further, one example embodiment may provide a method that provides an increase resolution of the eNB provided TA index value up to ITs. According to an example embodiment, this may be 16 times better than the legacy TA, without the need for TA related word length extensions (i.e., TA command, 11-bits or MAC CE TA update, 6-bits). In this case, the entire cell coverage may be divided into sectors, for which unique TA index values may be provided. For instance, in an example embodiment, TOA distance measurements may be used to solve any potential ambiguities related to interpretation of received TA index value. According to certain example embodiments, this may be beneficial for time division duplex (TDD), where an interference level between UL and DL transmission may be reduced.

Another example embodiment may provide a method that allows usage of a shorter TA- related word length. For example, as cell coverage may be divided into sectors, the TA index value range may be tailored to each sector size. In an example embodiment, if the TA resolution is not changed, a lower number of index values may be needed to cover the entire sector. Thus, a shorter word length may be used, which results in savings in radio resources.

According to other example embodiments, a method may be provided that uses TOA distance measurements as a reference. For example, the TOA distance may correspond to a true microwave path, and may include any reflected signal paths. Thus, it may correspond to TA, which may result in better accuracy with respect to position-based timing adjustment. Additionally, the UE may not have to report its position to the eNB or eNB NTN in order to receive an initial or accurate TA.

FIG. 5 illustrates an example scenario with three UEs at different distances within the cell, according to an example embodiment. As illustrated in FIG. 5, the cell coverage may be divided into two sectors, n =1 and n = 2. In certain example embodiments, a method may be provided that enables the eNB to broadcast or transmit TA range markers (TARM(X)), expressed in legacy TA steps (resolution 78 m). In an example embodiment, the TARM(X) marker indicates cell sector starting point. According to an example embodiment, this may define cell range sectors, for example, as illustrated in FIG. 5 for two sectors.

In an example embodiment, the eNB may calculate TA for the UE as per legacy based procedures on RACH preamble format and guard period. Then, the eNB may use TARM(X) as a reference point and omit the distance covered by TARM(X) marker. Thus, instead of a full TA index value, the eNB may transmit as a TA index value a remaining distance from the given TARM(X) marker to the given UE location. This way, for example, a shorter TA related word length may be used to provide necessary timing index value for the remaining distance. As such, this may in turn require less radio resources for signaling. In another example embodiment, a higher resolution TA may be provided, and the data may be controlled by the eNB.

According to an example embodiment, the UE may unambiguously determine a sector in which the UE is located. This may be done by the UE based on a TO A distance measurement (and expressed in index form), and by a received TA index value assessment. The UE may then apply correct timing adjustment based on the received TA value, and static offset indicated by the given TARM(X).

Certain example embodiments may be applied in any synchronous standard such as, for example, GSM, LTE, 5G, or NTN where there may be a need for UL channel synchronization. Other example embodiments may provide unique advantages in GPS- based initial timing adjustment used in NTN, and may be applied in a ground mobile network, for example, where TDD is used. Certain example embodiments may also provide more accurate timing adjustments that may be reduce cross channel interference.

According to certain example embodiments, FIG. 5 illustrates a scenario, where the TA resolution may be increased to 39 m, instead of 78 m. Further, the cell range, with respect to FIG. 2 used as a reference, may be in this case divided on two sectors N=2, denoted as n = 1 and n = 2. Here, N refers to the maximum number of sectors, and sector size may be the same or tailored to operator needs.

FIG. 6 illustrates TA index values provided by the eNB for three example UEs, according to an example embodiment. In particular, the TA index values may correspond to data presented at FIG. 3, and FIG. 6 illustrates TA steps and TOA measurements with respect to distance. FIGs. 3 and 6 illustrate exemplary data. For instance, sector n = 1 starts from 0 m (included) to 1282 * 39 m, which is 49998 m (50 km) (included), and covers TA index value ranges from 0 to 641. In addition, sector n = 2 starts from 49998 m (excluded) to 2 * 1282 * 39 m, which is 99996 m (100 km) (included), and covers Ta index value ranges from 642 to 1282.

Furthermore, as illustrated in FIG. 3, UE 1, which is at the TOA distance D(UE1) = 36.9 km, may have a TA index value TA(UEl) = 473 (473 * 78 m = 36.9 km).

In another example embodiment, in FIG. 6, UE1, which is at the TOA distance D(UE1) = 36.9 km is in sector n = 1. In addition, UE1 may have a TA index value TA(UEl) = 946 (946 * 39 m = 36.9 km).

According to an example embodiment, UE2 at FIG. 3 is at a TOA distance D(UE2) = 52.3 km, and may have a TA index value of TA(UE2) = 670 (670 * 78 m = 52.3 km). Furthermore, at FIG. 6, UE2 is at the TOA distance D(UE2) = 52.3 km, and is in sector n = 2. In addition, UE2 may have a TA index value TA(UE2) = 59. However, in an example embodiment, TA= 1341, which is 1282 * 39 m + 59 * 39 m = 52.3 km.

Additionally, in FIG. 3, UE3 may be at the TOA distance D(UE3) = 86.9 km, and may have a TA index value TA(UE3) = 1114 (1114 * 78 m = 86.9 km).

Further, in FIG. 6, UE3 may be at the TOA distance D(UE3) = 86.9 km, and may be in sector n = 2. UE3 may also have a TA index value TA(UE3) = 946. However, in an example embodiment, TA may be 2224, which is 1282 * 39 m + 946 * 39 m = 86.9 km.

According to certain example embodiments, for the scenario illustrated in FIG. 6, the TA index value for UE2 (59) may be lower than the TA value for UE1 (946). However, if these values are interpreted together with the TOA distance value, the UE may unambiguously apply necessary timing correction, namely: TA = 946 for UE1 and TA = 1282 + 59 for UE2, where 1TA = 39 m. As such, according to certain example embodiments, a higher TA resolution may be provided, and the TA related word length is not changed.

In an example embodiment, if higher TA resolution is not required (e.g., 78 m), in sectors n = 1 and n = 2, the TA index value range may be 641. This means that only 641 different index values may be needed to be addressed by the eNB, with respect to 1282. In addition, to address 641 values, in on example embodiment, a 10-bits word length may be sufficient with respect to 11 -bits that may be required for addressing 1282 unique values.

According to certain example embodiments, sectors may also be divided in various ways for which different TA related word lengths may be applied. In addition, the TA resolution improvement rationale may be determined by Ts (Eq. 5), which may correspond to a distance of 4,875 m, and may be considered as the smallest TA step. Thus, according to certain example embodiments, TA accuracy improvement ratio xl6 may be considered as the maximum possible improvement.

In certain example embodiments, using 11-bits word length and 1282 index values with, for example, 1TA = 4,875 m, a distance 6249.75 m may be unambiguously addressed. For instance, in a reference cell where 1TA = 78 m, a distance 99996 m may be covered. This may mean that the entire cell range may be divided into N = 16 sectors, with the same concept illustrated in FIGs. 5 and 6, where 2 sectors are established. The TOA distance measurements performed by the UE (Eq. 3, 4) may be used to determine the correct sector n, in which the UE is located, which enables correct understanding of the provided TA value. In certain example embodiments, 1282 may not be the maximum value as 11-bits provides the ability to address 2048 index values (0 to 2047).

Additionally, in another example embodiment, 6-bits word length and 64 index values (0 to 63), with step 1TA = 78 m, a distance 4992 m may be unambiguously addressed. For instance, in the reference cell, 1TA = 78 m, a distance 99996 m may be covered. This may mean that the entire cell range may be divided in at least N = 20 sectors, with the same concept as illustrated in FIGs. 5 and 6, where two sectors are established. In addition, in another example embodiment, the TOA distance measurements performed by the UE (Eq. 3, 4), may be used to determine the correct sector n, in which the UE is located, which provides a correct understanding of the provided TA value.

In certain example embodiments, TA accuracy may be improved, and TA word length may be reduced. In other example embodiments, the UE may be able to correctly determine the received TA index value based on TOA distance measurements. Further, in certain example embodiments, TA word length may be sector dependent.

According to an example embodiment, an 11-bits TA command may be replaced by a 6-bits word length and TOA measurements (Eq. 3, 4) used for unambiguous TA interpretation. To support this, the eNB may broadcast or transmit TARM(X), where X determines the given sector starting point. Further, TARM(X) may be expressed in legacy TA steps (i.e., 1TA = 78 m).

In an example embodiment, for 6-bits TA related word length, TARM(X) may be 0, 64, 128, 192, or 256. In such cases, the following parameters may be applicable: TARM(0) = 0 * 78 m = 0 m; and TARM(64) = 64 * 78 m = 4992 m. In certain example embodiments, the TARM(X) markers may be used as a reference or starting points (offsets) for each sector, and may be interpreted together with the provided TA value from the eNB in order to properly adjust UL timing.

According to an example embodiment, TARM(0) may be a starting point for sector n = 1, whereas TARM(64) may be a starting point for sector n = 2. In an example embodiment, selecting the starting point may be operator specific. For instance, a distance between two consecutive TARM(X) markers may need to be covered by TA index values with the given TA word length (e.g., 6-bits). A 6-bits word length may provide 64 unique TA values (0-63). If the TA minimal step is not changed (i.e., 78 m, 63*78m = 4914 m), the next sector may start 1 TA after, which means 64, as 64*78 m = 4992 m. In this example embodiment, TARM(0) and TARM(64) may determine starting points for the sectors. Further, in certain example embodiments, TARM(X) markers may be equally distributed (as in this example), or may be set independently by the operator. TARM(X) markers may also be part of the system information block (SIB), which means that such broadcast may be received by any UE within the given cell coverage. In an example embodiment, the UE within cell coverage, in an RRC IDLE or RRC CONNECTED state, may receive TOA data from the broadcast. According to one example embodiment, the broadcast may contain To time (physical reference signal transmission time, where the reference signal may be any frame, subframe, or symbol selected by the operator). Further, the UE may receive such reference signal at time Ti, and may perform TOA measurements as specified in Eq. 3, 4. According to an example embodiment, the TOA accuracy may be similar to TA. However, as TOA measurements together with TA value are used for unambiguous TA interpretation, even poor accuracy measurements may be enough for proper determination of the given n sector. In another example embodiment, in RRC IDLE state, since the UE does not make requests for radio resources, no further action may need to be taken. In addition, once the UE initiates RACH preamble, it may send Msg 1 towards the eNB. According to an example embodiment, the eNB may determine a T_A index value for the given UE.

In an example embodiment, at the eNB site, the eNB may compare TA with TARM(X) markers using Eq. 6 as follows:

TARM(X) < T_A < TARM(X + 1) [Eq. 6]

In Eq. 6, TARM(X) may represent a TA-based range marker for this sector, and TARM(X+1) may representing a TA-based range marker for the next sector. Further, TA may represent the TA calculated by the eNB for the given UE (1TA = 78 m).

According to an example embodiment, if TA for the given UE was determined to be TA = 80, then the UE may be at a distance 6240 m, with 1TA = 78 m. Then, TARM(X) = TARM(64) and TARM(X+1) = TARM(128), which means that this UE is in sector n = 2. Thus, according to certain example embodiments, the eNB may convert legacy obtained TA index value (80) to index value for the sector n = 2. From the obtained legacy TA index value, preceding TARM(64) may be subtracted to determine TA for the given sector TA(X), as specified in Eq. 7.

T_A(X) = T_A - TARM(X) [Eq. 7]

In Eq. 7, TARM(X) may represent a TA-based range marker for this sector. Further, TA may represent a TA calculated by the eNB for the given UE (1TA = 78 m), and TA(X) may represent a TA calculated by the eNB for the given UE (1TA = 78 m) for the remaining part.

According to an example embodiment, for example data, T_A(X) = 80 — 64 = 16, where 6240 = 64 * 78 + 16 * 78 = 4992 + 1248. In this case, distance 4992 m may be derived from TARM(64) in terms of required TA offset. The remaining part, 1248 m may equal TA(X), and Eq. 7 may be recalculated by the eNB to index form with a defined TA resolution for the given sector X, TAR(X), defined by Eqs. 8 and 8a shown below.

TARM(X+1)— TARM(X)

TAR(X) = [Eq. 8] T_A max

In Eqs. 8 and 8a, TARM(X) may represent a TA-based range marker for this sector, and TARM(X+1) may represent a TA-based range marker for the next sector. Further, T_A max may represent the maximum number of unique index values for TA signaling, for instance, TA related word length. In addition, IT_A may represent a TA minimal step (1TA = 78 m).

In an example embodiment, the following data may be provided: TARM(X) = 64; TARM(X+1) = 128; T_A max = 64; (ITA = 78 m); and 6-bits word length. Then,

128-64

TAR(X) = = 1.

64

As shown in the above equation, the TA resolution is not changed (Eq. 8), and may equal 78 m (Eq. 8a).

According to another example embodiment, if 7-bits TA word length is used for the same sector boundaries, then:

128 - 64

TAR(X) = = 0.5

128

In the above equation, the TA resolution may be 2x better (Eq. 8), and may equal 39 m (Eq. 8a). Then, T_A(X) (Eq. 7) may be expressed in a new scale of index values for the given sector, as specified in Eq. 9 shown below.

T_A(X) = (T_A - TARM(X)) * TAR(X) [Eq.9]

In Eq. 9, TARM(X) may represent a T_A-based range maker for this sector, and T_A may represent a TA calculated by the eNB for the given UE expressed in legacy T_A minimal steps (1TA = 78 m). In addition, TAR(X) may represent a TA resolution sector in n, and T_A(X) may represent a TA index value with minimal step specified for the given sector n.

Another example embodiment may include the following data: TARM(X) = 64; TAR(X) = 1 ; TA = 80 (1TA = 78 m); and a 6-bits word length. When applied to Eq. 9, the following may be obtained.

This may suggest that the index value T_A(X) = 16 needs to be coded on 6-bits word length, for example: 6-bits = T_A(X) = 010000, step 78 m.

A further example embodiment may include the following data: TARM(X) = 64; TAR(X) = 1; TA = 80 (1TA=78 m); and 7-bits word length. When applied to Eq. 9, the following may be obtained.

0,5 = 8 [Eq.9]

This may suggest that the index value T_A(X) = 8 needs to be coded on 7-bits word length, for example: 7-bits: T_A(X) = 0001000, step 39 m. As shown above, the TA index value may be provided to the given UE as a TA command, and the TA index value may be supported and have a different value with respect to legacy TA 11-bits convention (i.e., for TA = 80 and 11-bits). This may be shown by the following equation: 11-bits: TA(X) = 00001010000, step 78 m. This means that the UE may need to correctly interpret the received TA command in Msg 2 used for timing adjustment. If the TA command is wrongly interpret, the UE may not be able to establish an RRC connection. In an example embodiment, MSG 2, which may be a random access response, may include a TA command that may be 11-bits word length. The TA command may also include a TA index value calculated by the eNB for the UE.

In certain example embodiments, the TA command may be shorter (e.g., 6-bits instead of 11-bits), or the 1TA step may have a different value (e.g., 78 m). According to an example embodiment, selection may be operator specific, and configurations may be broadcasted as part of the SIB data, or they may be standardized.

According to an example embodiment, at the UE site, the UE may receive a TA correction in a TA Command. It maybe agreed whether shorten TA related word length is provided or allowed as a means for solving certain problems described herein. In addition, the same legacy word length may be provided, but TA resolution may be changed, as specified in Figs. 5 and 6. According to an example embodiment, the UE may determine a distance to the eNB by the TO A measurements (Eq. 3, 4). In addition, when the UE sends the RACH preamble, the UE may determine the eNB sector based on broadcasted or transmitted TARM(X) markers, and using TOA-based position expressed in index form representation (1TA= 78 m), as specified in Eq. 10 shown below.

TARM(X) < TA_d(T_s) < TARM(X + 1) [Eq. 10]

In Eq. 10, TARM(X) may representing a TA-based range marker for this sector received from the eNB. Further, TARM(X+1) may represent a TA-based range marker for the next sector received from the eNB, and TA_d(Ts) may represent a TOA-based equivalent of the TA index value. In an example embodiment, the above configuration of the UE may apply in the eNB part. For instance, the TA_d(Ts) value may differ from TA. However, TA_d(Ts) accuracy may still be sufficient to determine the correct sector n, as the received TA(X) value may provide insight to which sector the UE it should belong by solving equations stated in Eq. 10. This may be an issue at sector boundaries, for sector n, where the higher TA(X) value may indicate that the UE belongs to a previous sector, i.e. sector n-1, whereas a small TA(X) value may indicate that it is for the next sector, denoted as n+1. According to an example embodiment, the UE may not use the TA_d(Ts) value for RRC, but may use this value for TA(X) value unambiguous allocation to the given sector. Thus, in an example embodiment, the eNB may still remain responsible for the provision of TA corrections.

According to an example embodiment, the UE may use the provided TA value for UL to DL channel timing adjustment. However, as the received TA index value may be sector specific, a new equation may be used instead of Eq. 1 , such as, for example, Eq. 11 shown below.

As shown in Eq. 11 , TARM(X) may represent a TA-based range marker in index form for this sector, and Ts may represent the basic time unit. Further, TA(X) may represent a TA index value with minimal step specified for the given sector n, and TAR(X) may represent a TA resolution ratio in sector n. Further, TA_d(Ts) may represent a TOA- based equivalent of the TA index value used for sector n determination, and NTA(X) may represent a timing adjustment for the UE in the given sector n.

In an example embodiment, TARM(X) may be received from the eNB broadcast (SIB) or transmission, or it may be provided to the UE during the RRC CONNECTED state, where TA resolution optimization may be triggered on the later stage. In addition, TA(X) may be received as the TA command, and its value may be interpreted by the UE together with TA_d(Ts) index value for unambiguous sector n selection. Further, in an example embodiment, TAR(X) may be derived from the received eNB broadcast (SIB) or transmission, or may be provided directly. This may also contain information about TA related word length. As such, both sector boundaries and TA related word length may need to be provided to the UE.

An example embodiment may provide: int|[T_A(X); TA_d(T_s)] * TAR(X) * 16 * T_s | . This indicates the possibility that TAR(X) may have a different and fluent ratio, and that the integer form may be preserved for a number of Ts selection in the timing adjustment. In an example embodiment, TAR(X) may be quantized to an allowed form such as that shown in Eq. 12.

A^R(X) = l;f;i;i;V [Eq. 12]

In addition, Eq. 11 may be simplified to Eq. 1 la shown below.

N_TA(X) = TARM(X) * 16 * T_s + [T_A(X); TA_d(T_s)] * TAR(X) * 16 * T_s [Eq. 1 la]

As for TARM(X) * 16 * Ts, this may provide an indication of the static offset. The static offset may be proceeded with the legacy 1TA = 78 m step, and may be related to the initial TA, which may be set by the UE based on its position within the defined cell sectors (Eq. 10).

As for the part [T_A(X); TA_d(T_s)] * TAR(X) * 16 * T_s, the UE, after receiving the TA index value and unambiguous sector selection, may apply a TA correction with a higher resolution than the legacy resolution, if such was indicated by the eNB. This may also impact the minimal correction step at the UE (Eq. 5), which may be changed to Eq. 8a, as it may correspond to 16*Ts. Certain example embodiments may provide a TA index value unambiguous selection via a TOA method. For example, if the method is supported, the UE may receive TA correction decoded in shorten TA related word length (e.g., 6-bits). Then, by Eq. 10, the UE may be able to determine in which sector the UE is localized with respect to a distance from the eNB. According to an example embodiment, to determine a correct sector n, reference distance measurement such as propagation delay time may need to be of good quality. However, in certain example embodiments, reference distance measurement may be poor quality, and still may be sufficient for unambiguous sector n selection.

In an example embodiment, reference distance measurements accuracy should not be worse than half the size of the sector, which, for 6-bits TA related word length, may mean that the reference distance (or position) accuracy may be better than around 2500 m, as TA on 6-bits may cover a distance of 49992 m with 1TA = 78 m.

FIG. 7 illustrates an unambiguity sector selection, according to an example embodiment. For example, FIG. 7 illustrates a scenario in which four UEs may receive TA index value on 6-bits, which may need to be unambiguously allocated to the given sector (n-1, n, n+1). In an example embodiment, TOA-measurement may be assumed to be of poor quality, but the TA index value received from the eNB is always correct. In another example embodiment, the eNB may broadcast TARM(X) data with specified sector starting points.

As illustrated in FIG. 7, TA on 6-bits means that the TA index values may be unambiguous only in one sector, and in opposite sectors, values may be cyclically repeated. According to an example embodiment, a benefit may be that reduction of TA related signaling word length in the radio interface may be expected (e.g., from 11- to 6-bits). At the same time, the TOA distance measurement calculated by each UE may be expressed as per legacy, 11 -bits, as here, these data may not be seen over radio interface. For instance, in one example embodiment, for UE1, the eNB may calculate TA for UE1 to be equal to TA = 66 (11-bits). However, the eNB may send TA = 02 on 6-bits as the TA command in RAR as 66 = 64 + 2, where 64 may be covered by TARM(64) and indicates sector n. UE1 may receive TA = 02, and may also receive broadcast with TARM(X) data. UE1 may also perform TOA distance measurement to determine the TOA distance. UE1 may then compare its distance TOA = 66 with TARM(X) markers.

According to an example embodiment, a comparison may show thatUEl TOA distance is between TARM(64) and TARM(128), which may indicate that UE1 is within sector n. Further, received from the eNB, the TA index value may be small, which may indicate that this timing correction is for the beginning of sector n. In an example embodiment, UE1 may then add to received TA index value, static shift TARM(64). This means that effective TA may be equal to 64 + 02 = 66, which matches the value determined by the eNB for UE1.

In an example embodiment, for UE2, the eNB may use the same algorithm as for UE1. In addition, UE2 may be located near defined sector n-1 and n borders. In this case, reference distance measurement may be of poor quality (TOA=62), which means that sector n-1, and that sector n-1 was indicated for UE2. However, received by UE2, the TA index value may be low TA = 00 on 6-bits, which may suggest that may be for the beginning of the sector. This, however, may not be possible due to TOA method required accuracy error, which may be not more than 2500 m. This suggests that the UE2 may be allocated to the sector n, as the TA index value was more accurate in this case. Thus, according to an example embodiment, UE2 may apply correct TA, which may be equal to 64 + 00 = 64, the same as specified by the eNB.

According to an example embodiment, for UE3, a mirror case for UE2 may be illustrated. However, in this case, TOA distance may be high (TOA = 130, TA = 126). In an example embodiment, by using both the TOA value as a reference and the TA index value to determine beginning or ending part, it may be possible to determine the correct sector and apply correct timing correction by UE3. As for UE4, a failure case may be illustrated (TA = 65, TOA = 129). The reference distance accuracy error may be exceeded, which may result in the wrong sector being selected (n+1, instead of n). This may not be detected by the TA index value assignment (beginning or end). In an example embodiment, when the UE is in the middle of the TA index value range (not illustrated), the sector verification may be made easier, assuming that the allowed reference distance accuracy error is within tolerance.

In an example embodiment, by combination of the reference distance measurements (based on TOA) and TA index value assessment (beginning or end of TA range), it may be possible to unambiguously determine the correct sector from those indicated by the eNB via TARM(X) markers. It may also be possible to allocate adequate TA correction using shorter TA related word length.

According to an example embodiment, UE mobility handling by MAC CE TA update, 6-bits, may be provided. For instance, MAC CE TA update (Eq. 2) may be optimized for 6-bits TA related word length, which may be considered as optimum. However, a higher TA resolution may also be supported by modified Eq. 2, which may be specified as shown in Eq. 13 or Eq. 13a if TAR(X) meets the criteria of Eq. 12.

NTA(X) new = N_TA(X) _old + ([T_A(X); TA_d(T_s)] - 31) » 16 » TAR(X)

[Eq. 13 a]

As shown in Eq. 13 and Eq. 13a, TARM(X) may represent a TA-based range marker in index form for this sector, and Ts may represent a basic time unit. Further, TA(X) may represent a TA index value with minimal step specified for the given sector n, TAR(X) may represent a TA resolution ratio in sector n, and TA_d(Ts) may represent a TOA- based equivalent of the TA index value, used for sector n determination. In addition, NTA(X)_OM represents a current timing adjustment, if the method is supported, and N_TA(X)_new represents a new timing adjustment, if the method is supported. Thus, according to certain example embodiments, the UE may implement smaller increments of timing adjustment, which may depend on the TAR(X) ratio, Eq. 8.

FIG. 8 illustrates a signaling diagram of TA resolution enhancement with TOA-based verification, according to an example embodiment. As illustrated in FIG. 8, at 100 the UE may be in an RRC IDLE state. Further, at 102, the eNB may provision TOA data (To time), which may be considered as a prerequisite, and by provision of TARM(X) markers. According to an example embodiment, these data may be broadcasted (for UE in RRC IDLE/CONNECTED state) for instance, as part of SIB, or transmitted directly to the given UE (for UE in RRC CONNECTED state). Additionally, in an example embodiment, the eNB may provide information about TA related word length, or this may be predetermined. According to an example embodiment, the TARM(X) markers and TA related word length may be static or dynamically changed. Additionally, other parameters (e.g., sector size and TA resolution enhancement) may be derived based on these two data.

As illustrated in FIG. 8, at 104, the UE may receive a broadcast from the eNB with all the required data. With the received information, the UE may perform a TOA distance measurement at 106. However, if the UE is in RRC IDLE state, no further actions may be taken. Further, at 108, the UE may decide to switch from RRC IDLE to RRC CONNECTED. At 110, the UE may receive the most up to date TARM(X) and TA- related word length configuration from the eNB. Further, similar to 106, the UE may, at 112, perform a TOA distance measurement. Then, at 114, the UE may initiate RACH preamble by sending the preamble to the eNB. In an example embodiment, this may be the first possible moment for the UE to indicate its TOA-related capabilities, by for instance, provisioning of TOA distance measurements by Eq. 3 or Eq. 4, or by provision of TOA status information element. In an example embodiment, these data may be part of any further UL data, which means that the TA modification may be effective after such data is provided. As further illustrated in FIG. 8, at 116, the eNB may receive UE RACH preamble and confirmation, that the UE may support TA accuracy enhancement or shorten TA related word length. The eNB may then recalculate legacy TA value according to the last valid TARM(X) markers scheme, where the only remaining part may be then transmitted as the TA index value for the given UE. At 118, the eNB may send a message to the UE, which may be RAR. The message may contain a TA index value specified according to defined rules. Alternatively, in an example embodiment, the eNB may provide some status data, which may reflect for instance, accuracy of reference distance measurement (based on received data from the UE). In an example embodiment, the status data may include, for instance, TARM(X) markers configuration, or indicated TA-related word bits length. According to an example embodiment, this solution may be applied instead of SIB broadcasts. Alternatively, in other example embodiments, status data may include verification of whether TOA distance match TA distance. Additionally, the eNB may use status data to approve changes from legacy TA (11 -bits, 78 m) timing adjustment rules to new specific rules including, for example, 6 bits, 39 m.

At the reception of the message from 118, the UE may, at 120, determine a correct sector number based on TARM(X), reference distance in index representation TA_d(Ts), and timing advance T_A index value assessment. The UE may then, at 122, determine the correct T_A(X) value. At 124, the UE may perform an UL channel timing adjustment with T_A(X) resolution for the given sector, and apply the correct timing adjustment.

At 126 of FIG. 8, the UE may switch to RRC CONNECTED state. Once in RRC CONNECTED state, the UE may receive new settings, which may be included in the message sent at 128, which may be broadcast of dedicated transmission. In an example embodiment, the new settings may include new TA resolution (e.g., switch from 78 m to 39 m) applicable for the next timing adjustment related signaling, or new TARM(X) scheme may be forced. These new settings may also modify rules for TA calculations and interpretations. The UE may then, at 130, recalculate related settings without losing connection. In an example embodiment, new setting rules may be applied. For instance, TARM(64), which may be for sector n, may be changed to TARM(32). Thus, the received TA correction T_A(X) may have a different value. This may mean that the UE needs to recalculate this value accordingly (determine the sector and then interpret received TA value).

As illustrated in FIG. 8, at 132, the UE may send a dedicated message, or part of a regular UL transmission scope, which may contain related data, which may be used by the eNB. According to an example embodiment, this may lead to a decision as to whether the UE mobility should also be handled as specified herein. At 134, the eNB may keep the UE in-synch. In addition, this step may refer to mobility and continuous synchronization, where MAC CE TA Update, 6-bits is used. In addition, the timing aspect may not be covered, and legacy trigger may be used for MAC CE TA Update sending. In an example embodiment, in case of mobility, where a relative distance between the UE and eNB may change, TA enhancement may also be proposed. Here, a decision may be taken how to further proceed, which may be similar to 116. Further, at 136, the eNB may confirm whether the UE mobility should be handled as specified herein, and may provide MAC CE TA update including, for example, T_A(X) with TAR(X) for the given sector. This may be similar to 118, where the eNB may approve or change certain settings.

As further illustrated in FIG. 8, at 138, the UE may determine the sector based on TARM(X), D(Ts), and TA. Further, at 140, the UE may determine the correct T_A(X) value for mobility, and at 142, determine an UL channel timing adjustment for mobility with a T_A(X) resolution for the given sector. In addition, at 144, the UE may send further UL data to the eNB with UL timing adjustment. According to an example embodiment, if required, the initial settings may be modified both in terms of TA enhanced resolution, or TA related bit word length in order to assure optimal performance.

Certain example embodiments may provide support for NTN. For instance, certain example embodiments may be especially efficient for NTN application. As illustrated in FIG. 4, multipath propagation or connections via reflected signal may be present in the NTN operation. Additionally, due to a high-speed scenario, proper timing adjustment may be challenging. In an example embodiment, TOA distance may correspond to TA distance, as both may be based on the same microwave signals. This may provide a benefit with respect to positioning based timing adjustment (GPS).

FIG. 9 illustrates TA resolution enhancement in NTN, according to an example embodiment. In particular, for NTN, an additional benefit may be related to more efficient radio interface signaling, such as that illustrated in FIG. 9. For example, in NTN cell directed towards the Earth surface, the majority of UEs may be localized near the surface, as indicated by UE 1. UE2 may be considered as very rare, which may suggest that a majority of NTN cell range may not require allocation of TA index values, which may be needed only when some UE (UE2) will be detected by the eNB NTN during RACH preamble. Thus, TARM(X) markers may divide NTN cells on sectors such as TARM(X) = 0, 7500, 7564, 7618, etc., where 7500 * 78 = 58500 m. According to an example embodiment, sector boundaries may be defined for example as: for n = 1: (0 m, 585000 m) or in TA: (0, 7500); for n = 2: (585000 m, 58992 m) or in TA: (7500, 7563).

According to certain example embodiments, based on Eq.8a, the TA resolution may be very poor in sector n = 1, but as there may be no UE, there may be no problems. In an example embodiment, once UE2 is detected, the TARM(X) structure may be modified respectively. New TARM(X) scheme may be then broadcasted or transmitted to UEs. Further, UEs in the coverage may then recalculate TA related settings accordingly. In another example embodiment, UEs beyond sector n = 1 may apply 7500 as a static offset to timing adjustment as specified in Eq. 11 or Eq. 11a. In certain example embodiments, this may mean that there may be no need to define or allocate index values to cover the entire cell range, and no such data would need to be transmitted, if not required. Moreover, it may be possible to enhance TA accuracy, as previously described. FIG. 10 illustrates a flow diagram of a method, according to an example embodiment. In certain example embodiments, the flow diagram of FIG. 10 may be performed by a mobile station and/or UE, for instance similar to apparatus 10 illustrated in FIG. 12(a). According to one example embodiment, the method of FIG. 10 may include initially, at 200, receiving, at the UE, a broadcast including network range markers data from a network element. The method may also include, at 205, performing a distance measurement of the UE to the network element. In addition, at 210, the method may include sending a random-access channel preamble including the distance measurement to the network element. At 215, the method may include receiving a timing advance index value from the network element. Further, at 220, the method may include determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the UE is located. At 225, the method may include receiving new settings at the UE, and at 230, the method may include applying a corrected timing adjustment according to a resolution of the sector based on the distance measurement and the index value.

In an example embodiment, the UE may be in an RRC IDLE state or an RRC CONNECTED state. In another example embodiment, the distance measurement may be performed by TOA measurements, and the TOA measurements may be expressed in index form representation. According to another example embodiment, the sector may be determined based on broadcasted or transmitted reference markers of at least one sector, and the TOA measurements in index form representation.

FIG. 11 illustrates a flow diagram of another method, according to an example embodiment. In an example embodiment, the method of FIG. 11 may be performed by a telecommunications network, network entity or network node in a 3 GPP system, such as LTE or 5G-NR. For instance, in an example embodiment, the method of FIG. 11 may be performed by a base station, eNB, or gNB, MCG, SCG, PCell, or PSCell for instance similar to apparatus 20 illustrated in FIG. 12(b). According to an example embodiment, the method of FIG. 11 may include initially, at 300, determining network range markers data which partitions a cell coverage into sectors. The method may also include, at 305, calculating a timing advance value for a user equipment. At 310, the method may include determining a timing advance index value based on the calculated timing advance value and the network range markers data. Further, at 315, the method may include sending the timing advance index value to the UE for channel timing adjustment.

According to an example embodiment, the method may further include, at 320, sending a broadcast including the network range markers data to the UE. In addition, the method may include, at 325, receiving, in response to the broadcast, time of arrival related capabilities of the UE. The method may also include, at 330, determining a timing advance resolution ratio for a given sector. Further, the method may include, at 335, providing an updated timing index value and an updated timing resolution ratio to the use UE. In an example embodiment, the time of arrival related capabilities may be received via a random-access channel preamble. In another example embodiment, the timing advance index value may be sent via a random access response. According to a further example embodiment, the random access response may include status data reflecting accuracy of the time of arrival related capabilities.

FIG. 12(a) illustrates an apparatus 10 according to an example embodiment. In an embodiment, apparatus 10 may be a node or element in a communications network or associated with such a network, such as a UE, mobile equipment (ME), mobile station, mobile device, stationary device, IoT device, or other device. As described herein, UE may alternatively be referred to as, for example, a mobile station, mobile equipment, mobile unit, mobile device, user device, subscriber station, wireless terminal, tablet, smart phone, IoT device, sensor or NB-IoT device, or the like. As one example, apparatus 10 may be implemented in, for instance, a wireless handheld device, a wireless plug-in accessory, or the like. In some example embodiments, apparatus 10 may include one or more processors, one or more computer-readable storage medium (for example, memory, storage, or the like), one or more radio access components (for example, a modem, a transceiver, or the like), and/or a user interface. In some embodiments, apparatus 10 may be configured to operate using one or more radio access technologies, such as GSM, LTE, LTE-A, NR, 5G, WLAN, WiFi, NB-IoT, Bluetooth, NFC, MulteFire, and/or any other radio access technologies. It should be noted that one of ordinary skill in the art would understand that apparatus 10 may include components or features not shown in FIG. 12(a).

As illustrated in the example of FIG. 12(a), apparatus 10 may include or be coupled to a processor 12 for processing information and executing instructions or operations. Processor 12 may be any type of general or specific purpose processor. In fact, processor 12 may include one or more of general-purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), and processors based on a multi-core processor architecture, as examples. While a single processor 12 is shown in FIG. 12(a), multiple processors may be utilized according to other embodiments. For example, it should be understood that, in certain example embodiments, apparatus 10 may include two or more processors that may form a multiprocessor system (e.g., in this case processor 12 may represent a multiprocessor) that may support multiprocessing. According to certain example embodiments, the multiprocessor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster).

Processor 12 may perform functions associated with the operation of apparatus 10 including, as some examples, precoding of antenna gain/phase parameters, encoding and decoding of individual bits forming a communication message, formatting of information, and overall control of the apparatus 10, including processes illustrated in FIGs. 1-10. Apparatus 10 may further include or be coupled to a memory 14 (internal or external), which may be coupled to processor 12, for storing information and instructions that may be executed by processor 12. Memory 14 may be one or more memories and of any type suitable to the local application environment, and may be implemented using any suitable volatile or nonvolatile data storage technology such as a semiconductor-based memory device, a magnetic memory device and system, an optical memory device and system, fixed memory, and/or removable memory. For example, memory 14 can be comprised of any combination of random access memory (RAM), read only memory (ROM), static storage such as a magnetic or optical disk, hard disk drive (HDD), or any other type of non-transitory machine or computer readable media. The instructions stored in memory 14 may include program instructions or computer program code that, when executed by processor 12, enable the apparatus 10 to perform tasks as described herein.

In an embodiment, apparatus 10 may further include or be coupled to (internal or external) a drive or port that is configured to accept and read an external computer readable storage medium, such as an optical disc, USB drive, flash drive, or any other storage medium. For example, the external computer readable storage medium may store a computer program or software for execution by processor 12 and/or apparatus 10 to perform any of the methods illustrated in FIGs. 1-10.

In some embodiments, apparatus 10 may also include or be coupled to one or more antennas 15 for receiving a downlink signal and for transmitting via an uplink from apparatus 10. Apparatus 10 may further include a transceiver 18 configured to transmit and receive information. The transceiver 18 may also include a radio interface (e.g., a modem) coupled to the antenna 15. The radio interface may correspond to a plurality of radio access technologies including one or more of GSM, LTE, LTE-A, 5G, NR, WLAN, NB-IoT, Bluetooth, BT-LE, NFC, RFID, UWB, and the like. The radio interface may include other components, such as filters, converters (for example, digital-to-analog converters and the like), symbol demappers, signal shaping components, an Inverse Fast Fourier Transform (IFFT) module, and the like, to process symbols, such as OFDMA symbols, carried by a downlink or an uplink.

For instance, transceiver 18 may be configured to modulate information on to a carrier waveform for transmission by the antenna(s) 15 and demodulate information received via the antenna(s) 15 for further processing by other elements of apparatus 10. In other embodiments, transceiver 18 may be capable of transmitting and receiving signals or data directly. Additionally or alternatively, in some embodiments, apparatus 10 may include an input and/or output device (I/O device). In certain embodiments, apparatus 10 may further include a user interface, such as a graphical user interface or touchscreen.

In an embodiment, memory 14 stores software modules that provide functionality when executed by processor 12. The modules may include, for example, an operating system that provides operating system functionality for apparatus 10. The memory may also store one or more functional modules, such as an application or program, to provide additional functionality for apparatus 10. The components of apparatus 10 may be implemented in hardware, or as any suitable combination of hardware and software. According to an example embodiment, apparatus 10 may optionally be configured to communicate with apparatus 10 via a wireless or wired communications link 70 according to any radio access technology, such as NR.

According to certain example embodiments, processor 12 and memory 14 may be included in or may form a part of processing circuitry or control circuitry. In addition, in some embodiments, transceiver 18 may be included in or may form a part of transceiving circuitry.

As discussed above, according to certain example embodiments, apparatus 10 may be a UE for example. According to certain embodiments, apparatus 10 may be controlled by memory 14 and processor 12 to perform the functions associated with example embodiments described herein. For instance, in one embodiment, apparatus 10 may be controlled by memory 14 and processor 12 to receive a broadcast comprising network range markers data from a network element. Apparatus 10 may also be controlled by memory 14 and processor 12 to perform a distance measurement of the user equipment to the network element. Apparatus 10 may further be controlled by memory 14 and processor 12 to determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located. In addition, apparatus 10 may be controlled by memory 14 and processor 12 to receive a timing advance index value from the network element. Further, apparatus 10 may be controlled by memory 14 and processor 12 to apply a corrected timing adjustment according to a resolution of the sector based on the distance measurement and the index value. Apparatus 10 may further be controlled by memory 14 and processor 12 to send a random-access channel preamble including the distance measurement to the network element. Apparatus 10 may also be controlled by memory 14 and processor 12 to receive new settings, and apply a correct timing adjustment according to a resolution of the sector based on the index value.

FIG. 12(b) illustrates an apparatus 20 according to an example embodiment. In an example embodiment, the apparatus 20 may be a RAT, node, host, or server in a communication network or serving such a network. For example, apparatus 20 may be a base station, a Node B, an evolved Node B (eNB), 5G Node B or access point, next generation Node B (NG-NB or gNB), and/or WLAN access point, associated with a radio access network (RAN), such as an LTE network, 5G or NR. It should be noted that one of ordinary skill in the art would understand that apparatus 20 may include components or features not shown in FIG. 12(b).

As illustrated in the example of FIG. 12(b), apparatus 20 may include a processor 22 for processing information and executing instructions or operations. Processor 22 may be any type of general or specific purpose processor. For example, processor 22 may include one or more of general-purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), and processors based on a multi-core processor architecture, as examples. While a single processor 22 is shown in FIG. 12(b), multiple processors may be utilized according to other embodiments. For example, it should be understood that, in certain embodiments, apparatus 20 may include two or more processors that may form a multiprocessor system (e.g., in this case processor 22 may represent a multiprocessor) that may support multiprocessing. In certain embodiments, the multiprocessor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster.

According to certain example embodiments, processor 22 may perform functions associated with the operation of apparatus 20, which may include, for example, precoding of antenna gain/phase parameters, encoding and decoding of individual bits forming a communication message, formatting of information, and overall control of the apparatus 20, including processes illustrated in FIGS. 1-9 and 11.

Apparatus 20 may further include or be coupled to a memory 24 (internal or external), which may be coupled to processor 22, for storing information and instructions that may be executed by processor 22. Memory 24 may be one or more memories and of any type suitable to the local application environment, and may be implemented using any suitable volatile or nonvolatile data storage technology such as a semiconductor-based memory device, a magnetic memory device and system, an optical memory device and system, fixed memory, and/or removable memory. For example, memory 24 can be comprised of any combination of random access memory (RAM), read only memory (ROM), static storage such as a magnetic or optical disk, hard disk drive (HDD), or any other type of non-transitory machine or computer readable media. The instructions stored in memory 24 may include program instructions or computer program code that, when executed by processor 22, enable the apparatus 20 to perform tasks as described herein. In an embodiment, apparatus 20 may further include or be coupled to (internal or external) a drive or port that is configured to accept and read an external computer readable storage medium, such as an optical disc, USB drive, flash drive, or any other storage medium. For example, the external computer readable storage medium may store a computer program or software for execution by processor 22 and/or apparatus 20 to perform the methods illustrated in FIGs. 1-9 and 11.

In certain example embodiments, apparatus 20 may also include or be coupled to one or more antennas 25 for transmitting and receiving signals and/or data to and from apparatus 20. Apparatus 20 may further include or be coupled to a transceiver 28 configured to transmit and receive information. The transceiver 28 may include, for example, a plurality of radio interfaces that may be coupled to the antenna(s) 25. The radio interfaces may correspond to a plurality of radio access technologies including one or more of GSM, NB-IoT, LTE, 5G, WLAN, Bluetooth, BT-LE, NFC, radio frequency identifier (RFID), ultrawideband (UWB), MulteFire, and the like. The radio interface may include components, such as filters, converters (for example, digital-to- analog converters and the like), mappers, a Fast Fourier Transform (FFT) module, and the like, to generate symbols for a transmission via one or more downlinks and to receive symbols (for example, via an uplink).

As such, transceiver 28 may be configured to modulate information on to a carrier waveform for transmission by the antenna(s) 25 and demodulate information received via the antenna(s) 25 for further processing by other elements of apparatus 20. In other embodiments, transceiver 18 may be capable of transmitting and receiving signals or data directly. Additionally or alternatively, in some embodiments, apparatus 20 may include an input and/or output device (I/O device).

In an embodiment, memory 24 may store software modules that provide functionality when executed by processor 22. The modules may include, for example, an operating system that provides operating system functionality for apparatus 20. The memory may also store one or more functional modules, such as an application or program, to provide additional functionality for apparatus 20. The components of apparatus 20 may be implemented in hardware, or as any suitable combination of hardware and software. According to some embodiments, processor 22 and memory 24 may be included in or may form a part of processing circuitry or control circuitry. In addition, in some embodiments, transceiver 28 may be included in or may form a part of transceiving circuitry. As used herein, the term “circuitry” may refer to hardware-only circuitry implementations (e.g., analog and/or digital circuitry), combinations of hardware circuits and software, combinations of analog and/or digital hardware circuits with software/firmware, any portions of hardware processor(s) with software (including digital signal processors) that work together to cause an apparatus (e.g., apparatus 10 and 20) to perform various functions, and/or hardware circuit(s) and/or processor(s), or portions thereof, that use software for operation but where the software may not be present when it is not needed for operation. As a further example, as used herein, the term “circuitry” may also cover an implementation of merely a hardware circuit or processor (or multiple processors), or portion of a hardware circuit or processor, and its accompanying software and/or firmware. The term circuitry may also cover, for example, a baseband integrated circuit in a server, cellular network node or device, or other computing or network device.

As introduced above, in certain embodiments, apparatus 20 may be a radio resource manager, RAT, node, host, or server in a communication network or serving such a network. For example, apparatus 20 may be a satellite, base station, a Node B, an evolved Node B (eNB), 5G Node B or access point, next generation Node B (NG-NB or gNB), and/or WLAN access point, associated with a radio access network (RAN), such as an LTE network, 5G or NR. According to certain embodiments, apparatus 20 may be controlled by memory 24 and processor 22 to perform the functions associated with any of the embodiments described herein.

For instance, in one embodiment, apparatus 20 may be controlled by memory 24 and processor 22 to determine network range markers data which partitions a cell coverage into sectors. Apparatus 20 may also be controlled by memory 24 and processor 22 to calculate a timing advance value for a UE. In addition, apparatus 20 may be controlled by memory 24 and processor 22 to determine a timing advance index value based on the calculated timing advance value and the network range markers data. Further, apparatus 20 may be controlled by memory 24 and processor 22 to send the timing advance index value to the UE for channel timing adjustment. Apparatus 20 may also be controlled by memory 24 and processor 22 to send a broadcast comprising the network range markers data to the UE. In addition, apparatus 20 may be controlled by memory 24 and processor 22 to receive, in response to the broadcast, time of arrival related capabilities of the UE. Apparatus 20 may also be controlled by memory 24 and processor 22 to determine a timing advance resolution ratio for a given sector. Apparatus 20 may further be controlled by memory 24 and processor 22 to provide an updated timing index value and an updated timing resolution ratio to the UE. Certain example embodiments described herein provide several technical improvements, enhancements, and /or advantages. In some example embodiments, it may be possible to enhance TA accuracy, where the eNB may still be responsible for provisioning and maintaining the timing correction to the UE within coverage, without the need for longer TA related word length. Additionally, the eNB may deliver TA index values with accuracy up to ITs, which may be 4,875 m for LTE. According to other example embodiments, it may be possible to reduce the required TA related word length for TA correction, for example, from 11 -bits TA Command to 6-bits TA Command in RAR. Thus, 5-bits shorten word length may be used, which enables saving of radio resources. In other example embodiments, a combination of the above-described advantages may be achieved and tailored to the specific demands to the given sector. This then, may improve UL timing adjustment, which may be beneficial for instance, for reducing UL to DL interfaces in TDD. Moreover, in other example embodiments, the TARM(X) concept may be efficient in NTN, where a majority of the cell is not occupied.

According to other example embodiments, the UE may not be required to calculate or provide its positioning data to the eNB in order to receive initial timing adjustment. Thus, user privacy may be protected. In addition, the procedures described herein may be simplified with less radio resources that may be needed for related signaling. Other example embodiments may be applied in any synchronous standard including, for example, GSM, LTE, 5G, and NTN where there may be a need for UL channel synchronization. This may be especially true where TDD is used, and where more accurate timing adjustment may reduce cross channel interferences.

A computer program product may comprise one or more computer-executable components which, when the program is run, are configured to carry out some example embodiments. The one or more computer-executable components may be at least one software code or portions of it. Modifications and configurations required for implementing functionality of an example embodiment may be performed as routine(s), which may be implemented as added or updated software routine(s). Software routine(s) may be downloaded into the apparatus.

As an example, software or a computer program code or portions of it may be in a source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, distribution medium, or computer readable medium, which may be any entity or device capable of carrying the program. Such carriers may include a record medium, computer memory, read-only memory, photoelectrical and/or electrical carrier signal, telecommunications signal, and software distribution package, for example. Depending on the processing power needed, the computer program may be executed in a single electronic digital computer or it may be distributed amongst a number of computers. The computer readable medium or computer readable storage medium may be a non-transitory medium. In other example embodiments, the functionality may be performed by hardware or circuitry included in an apparatus (e.g., apparatus 10 or apparatus 20), for example through the use of an application specific integrated circuit (ASIC), a programmable gate array (PGA), a field programmable gate array (FPGA), or any other combination of hardware and software. In yet another example embodiment, the functionality may be implemented as a signal, a non-tangible means that can be carried by an electromagnetic signal downloaded from the Internet or other network.

According to an example embodiment, an apparatus, such as a node, device, or a corresponding component, may be configured as circuitry, a computer or a microprocessor, such as single-chip computer element, or as a chipset, including at least a memory for providing storage capacity used for arithmetic operation and an operation processor for executing the arithmetic operation.

One having ordinary skill in the art will readily understand that the invention as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although the invention has 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 example embodiments. Although the above embodiments refer to 5G NR and LTE technology, the above embodiments may also apply to any other present or future 3GPP technology, such as LTE-advanced, and/or fourth generation (4G) technology. A first embodiment is directed to a method that may include receiving, at a user equipment, a broadcast comprising network range markers data from a network element. The method may also include performing a distance measurement of the user equipment to the network element. The method may further include, determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located.

In a variant, the method may further include receiving a timing advance index value from the network element.

In a variant, the method may further include applying a corrected timing adjustment according to a resolution of the sector based on the distance measurement and the index value.

In a variant, the method may further include sending a random-access channel preamble including the distance measurement to the network element.

In a variant, the method may further include receiving new settings at the user equipment.

In a variant, the user equipment may be in a radio resource control idle state or a radio resource control connected state.

In a variant, the distance measurement may be performed by time of arrival measurements, and the time of arrival measurements may be expressed in index form representation.

In a variant, the sector may be determined based on broadcasted or transmitted reference markers of at least one sector, and the time of arrival measurements in index form representation. A second embodiment may be directed to a method that may include determining, by a network element, network range markers data which partitions a cell coverage into sectors. The method may also include calculating a timing advance value for a user equipment. The method may further include determining a timing advance index value based on the calculated timing advance value and the network range markers data. The method may also include sending the timing advance index value to the user equipment for channel timing adjustment.

In a variant, the method may further include sending, from the network element, a broadcast including the network range markers data to the user equipment.

In a variant, the method may further include receiving, in response to the broadcast, time of arrival related capabilities of the user equipment.

In a variant, the method may further include determining a timing advance resolution ratio for a given sector.

In a variant, the method may further include providing an updated timing index value and an updated timing resolution ratio to the user equipment.

In a variant, the time of arrival related capabilities may be received via a random-access channel preamble.

In a variant, the timing advance index value may be sent via a random access response.

In a variant, the random access response may include status data reflecting accuracy of the time of arrival related capabilities.

Another embodiment is directed to an apparatus including at least one processor and at least one memory including computer program code. The at least one memory and the computer program code may be configured, with the at least one processor, to cause the apparatus at least to perform the method according to the first embodiment or the second embodiment or any of their variants discussed above. Another embodiment is directed to an apparatus that may include circuitry configured to perform the method according to the first embodiment or the second embodiment or any of their variants.

Another embodiment is directed to an apparatus that may include means for performing the method according to the first embodiment or the second embodiment or any of their variants.

Another embodiment is directed to a computer readable medium including program instructions stored thereon for performing at least the method according to the first embodiment or the second embodiment or any of their variants

Partial Glossary eNB Enhanced Node B gNB 5G or NR Base Station LTE Long Term Evolution

MAC Medium Access Control

MAC CE MAC Command Element

NTN Non-Terrestrial Network

NR New Radio PRACH Physical Random Access Channel

RAR Random Access Response

TA Timing Advance

TAR Timing Advance Resolution Ratio

TARM Timing Advance Range Marker TDD Time Division Duplex TOA Time of Arrival

UE User Equipment

Claims

CLAIMS:

1. A method, comprising: receiving, at a user equipment, a broadcast comprising network range markers data from a network element; performing a distance measurement of the user equipment to the network element; and determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located.

2. The method according to claim 1, further comprising receiving a timing advance index value from the network element.

3. The method according to claim 2, further comprising applying a corrected timing adjustment according to a resolution of the sector based on the distance measurement and the timing advance index value.

4. The method according to any of claims 1-3, further comprising sending a random-access channel preamble comprising the distance measurement to the network element.

5. The method according to any of claims 1 -4, further comprising receiving settings at the user equipment.

6. A method, comprising: determining, by a network element, network range markers data which partitions a cell coverage into sectors; calculating a timing advance value for a user equipment; determining a timing advance index value based on the calculated timing advance value and the network range markers data; and sending the timing advance index value to the user equipment.

7. The method according to claim 6, further comprising sending, from the network element, a broadcast comprising the network range markers data to the user equipment.

8. The method according to claims 6 or 7, further comprising receiving time of arrival related capabilities of the user equipment.

9. The method according to claim 8, wherein the time of arrival related capabilities are received via a random-access channel preamble.

10. The method according to any of claims 6-9, further comprising determining a timing advance resolution ratio for a given sector.

11. The method according to any of claims 6-10, further comprising providing an updated timing advance index value and an updated timing advance resolution ratio to the user equipment.

12. An apparatus, comprising: at least one processor; and at least one memory comprising computer program code, the at least one memory and the computer program code are configured, with the at least one processor to cause the apparatus at least to receive a broadcast comprising network range markers data from a network element; perform a distance measurement of the apparatus to the network element; and determine, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the apparatus is located.

13. The apparatus according to claim 12, wherein the at least one memory and the computer program code are further configured, with the at least one processor to cause the apparatus at least to receive a timing advance index value from the network element.

14. The apparatus according to claiml3, wherein the at least one memory and the computer program code are further configured, with the at least one processor to cause the apparatus at least to apply a corrected timing adjustment according to a resolution of the sector based on the distance measurement and the timing advance index value.

15. The apparatus according to any of claims 12-14, wherein the at least one memory and the computer program code are further configured, with the at least one processor to cause the apparatus at least to send a random-access channel preamble comprising the distance measurement to the network element.

16. The apparatus according to any of claims 12-15, wherein the at least one memory and the computer program code are further configured, with the at least one processor to cause the apparatus at least to receive settings at the apparatus.

17. An apparatus, comprising: at least one processor; and at least one memory including computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor to cause the apparatus at least to determine network range markers data which partitions a cell coverage into sectors; calculate a timing advance value for a user equipment; determine a timing advance index value based on the calculated timing advance value and the network range markers data; and send the timing advance index value to the user equipment.

18. The apparatus according to claim 17, wherein the at least one memory and the computer program code are further configured, with the at least one processor to cause the apparatus at least to send a broadcast comprising the network range markers data to the user equipment.

19. The apparatus according to claims 17 or 18, wherein the at least one memory and the computer program code are further configured, with the at least one processor to cause the apparatus at least to receive time of arrival related capabilities of the user equipment.

20. The apparatus according to claim 19, wherein the time of arrival related capabilities are received via a random-access channel preamble.

21. The apparatus according to any of claims 17-20, wherein the at least one memory and the computer program code are further configured, with the at least one processor to cause the apparatus at least to determine a timing advance resolution ratio for a given sector.

22. The apparatus according to any of claims 17-21, wherein the at least one memory and the computer program code are further configured, with the at least one processor to cause the apparatus at least to provide an updated timing advance index value and an updated timing advance resolution ratio to the user equipment.

23. An apparatus, comprising: means for receiving, at a user equipment, a broadcast comprising network range markers data from a network element; means for performing a distance measurement of the user equipment to the network element; and means for determining, according to the network range markers data and the measured distance, a sector of a cell coverage area at which the user equipment is located.

24. An apparatus, comprising: means for determining, by a network element, network range markers data which partitions a cell coverage into sectors; means for calculating a timing advance value for a user equipment; means for determining a timing advance index value based on the calculated timing advance value and the network range markers data; and means for sending the timing advance index value to the user equipment.

25. A non- transitory computer readable medium comprising program instructions stored thereon for performing the method according to any of claims 1-11.