EP4684585A1 - Network node and method for handling random access related delays in a wireless communications network - Google Patents

Abstract

A method performed by a network node is provided. The method is for handling delays related to Random Access, RA, preambles in a wireless communications network in which multiple Radio Head devices, RHs, are operating. Each respective RH out of the multiple RHs are connected to a baseband unit via a radio unit in a respective branch, and is serving at least one User Equipment, UE, from which RA preambles are to be received. For each respective branch the network node configures (201) a first delay to compensate for a measured time-of-arrival value in the branch, The network node maps (202) to each respective RH out of the multiple RHs, the RH's related first delay, at least one RA preamble associated with the RH, and an interval in a detection window of an RA preamble receiver in the baseband unit. The interval is determined based on the first delay between the RH and the baseband unit. The interval is a signal detection interval related to the at least one RA preamble. When receiving a preamble signal in one of the intervals, the network node decides (203) which first delay to use based on the mapped intervals.

Description

NETWORK NODE AND METHOD FOR HANDLING RANDOM ACCESS RELATED DELAYS IN A WIRELESS COMMUNICATIONS NETWORK

TECHNICAL FIELD

Embodiments herein relate to a network node and a methods therein. In some aspects, they relate to handling delays related to Random Access (RA) preambles in a wireless communications network in which multiple Radio Head devices (RH)s are operating.

BACKGROUND

In a typical wireless communication network, wireless devices, also known as wireless communication devices, mobile stations, stations (STA) and/or User Equipment (UE), communicate via a Wide Area Network or a Local Area Network such as a Wi-Fi network or a cellular network comprising a Radio Access Network (RAN) part and a Core Network (CN) part. The RAN covers a geographical area which is divided into service areas or cell areas, which may also be referred to as a beam or a beam group, with each service area or cell area being served by a radio network node such as a radio access node e.g., a Wi-Fi access point, a Base Station (BS) or a radio base station (RBS), which in some networks may also be denoted, for example, a Base Station (BS), a NodeB, eNodeB (eNB), or gNodeB (gNB) as denoted in Fifth Generation (5G) telecommunications. A service area or cell area is a geographical area where radio coverage is provided by the radio network node. The radio network node communicates over an air interface operating on a radio frequency with the wireless devices within the range of the radio network node.

3rd Generation Partnership Project (3GPP) is the standardization body for specifying the standards for the cellular system evolution, e.g., including 3G, 4G, 5G and the future evolutions. Specifications for Evolved Universal Terrestrial Radio Access (E- UTRA) and Evolved Packet System (EPS) have been completed within the 3GPP. In 4G also called a Fourth Generation (4G) network, EPS is core network and E-UTRA is radio access network. In 5G, 5GC is core network, NR is radio access network. As a continued network evolution, the new release of 3GPP specifies a 5G network also referred to as 5G New Radio (NR) and 5G Core (5GC).

Frequency bands for 5G NR are being separated into two different frequency ranges, Frequency Range 1 (FR1) and Frequency Range 2 (FR2). FR1 comprises sub-6 GHz frequency bands. Some of these bands are bands traditionally used by legacy standards but have been extended to cover potential new spectrum offerings from 410 MHz to 7125 MHz. FR2 comprises frequency bands from 24.25 GHz to 52.6 GHz. Bands in this millimeter wave range have shorter range but higher available bandwidth than bands in the FR1.

Multi-antenna techniques may significantly increase the data rates and reliability of a wireless communication system. For a wireless connection between a single user, such as UE, and a base station (BS), the performance is in particular improved if both the transmitter and the receiver are equipped with multiple antennas, which results in a Multiple-Input Multiple-Output (MIMO) communication channel. This may be referred to as Single-User (SU)-MIMO. In the scenario where MIMO techniques is used for the wireless connection between multiple users and the base station, MIMO enables the users to communicate with the base station simultaneously using the same time-frequency resources by spatially separating the users, which increases further the cell capacity. This may be referred to as Multi-User (MU)-MIMO. Note that MU-MIMO may benefit when each UE only has one antenna. The cell capacity can be increased linearly with respect to the number of antennas at the BS side. Due to that, more and more antennas are employed in BS. Such systems and/or related techniques are commonly referred to as massive MIMO.

In several mobile communications systems, e.g., LTE and NR, uplink (UL) transmissions from a UE to a base station must be time synchronized for the system to work properly. From a Random-Access (RA) preamble detection, a time-of-arrival estimate can be made, and a so-called timing advance (TA) command is sent to the UE. The UE then adjusts its transmission timing per the timing advance command and becomes time synchronized.

The RA preambles in LTE and NR comprise one or more periods or symbols of a RA preamble sequence plus a cyclic prefix. A cyclic prefix when used herein e.g. means a copy of the end of the sequence added before the first symbol when forming the preamble. The symbol period limits the range of round-trip times for the UE that can easily be estimated in the base station and subsequently be used for timing advance commands. A round-trip time when used herein, e.g. means the amount of time it takes for a signal to be sent from the base station (BS) to the UE plus the amount of time it takes for the signal sent from the UE to the BS. RA preamble sequences are generated via cyclic shifts of a root sequence. A cyclic shift when used herein e.g. means that an initial part of the root sequence is moved to the end of the root sequence to form a preamble sequence. The minimum non-zero cyclic shift, determined by the preamble period and a parameter N_cs, determines the maximum supported round-trip time in a cell.

In a typical scenario, an RA preamble configuration is such that preambles can be correctly detected for all UEs in a cell, with round-trip times ranging from zero to the minimum non-zero cyclic shift. The larger the supported round-trip time, the more randomaccess root sequences are needed in a cell that increases the need for random-access preamble processing. A root sequence when used herein e.g. means a Zadoff-Chu sequence.

In an example of an indoor connect solution, several radio dots, also referred to as Radio Head devices (RH)s, may be connected to a single baseband unit via one or more indoor radio units and interconnect units that introduce further delays. It should be noted that the wordings radio dot and RH is used interchangeably herein. A 5G radio dot functions as a small cell in a 5G wireless network to meet indoor coverage requirements at high speed to provide superior user experience. It is compliant with the 3GPP standard and boosts throughput to over 2 Gbps. For example, for a radio dot close to a UE, the signal from the radio dot to the baseband unit is delayed with a delay composed of propagation delay from radio dot to an indoor radio unit, and a delay from the indoor radio unit to the baseband unit, possibly via an interconnect unit. Analogously, there are delays in the direction from the baseband unit to the radio dot. The total round-trip time between the baseband unit and the indoor radio unit 0 is T₀ and the round-trip time between the radio dot and the indoor radio unit is T₀₁. In the following, the terms delay and round-trip time are used interchangeably. Moreover, the delay between a radio unit i and baseband unit is labelled T_i and the delay between radio dot ij and its indoor radio unit is denoted T_ij. Finally, the maximum round-trip time between the same radio dot and a UE communicating via the dot is ΔT_ij.

In an indoor connect scenario, the total delay between a radio dot and the baseband unit may be much larger than the propagation delay from a UE to the closest radio dot. In some indoor connect scenarios, the delay is even larger than the maximum round-trip time that can be supported for the used Physical Random Access Channel (PRACH) format, which is the random-access preamble symbol time T_symb. Since the randomaccess preamble is periodic, a matched filter will produce a peak at T = ( T_i + is much smaller than the whole preamble duration and the UE is very close to the dot. To simplify the notation, let be the total delay between radio dot ij and the baseband unit via an indoor radio unit Since the air propagation is less than or equal to will be in the interval given by

In an indoor connect solution, the delay is known and the maximum dot-UE delay is known to be small compared to T_symb- That is valid for all UEs in the cell and the timing advance command value T_TA to be transmitted to a UE connected to radio dot ij and radio unit i is then preconfigured correction and |x] is the largest integer less than or equal to x.

SUMMARY

As a part of developing embodiments herein a problem was identified by the inventors and will first be discussed.

In the current indoor connect solution, the baseband unit compensates the measured time-of-arrival value τ with a preconfigured delay 77, assuming that all UEs have very limited air propagation delay, e.g., the common delay from the radio dot to the baseband unit is 100 ps while there is a maximum delay of 1 ps for air propagation. This approach cannot support more complex scenarios and/or deployments e.g., if there are two delay groups, e.g., one at 100 ps and one at 150 ps, connected to an indoor connect solution due to different cable lengths from indoor radio units to the indoor connect radio dots.

An object of embodiments herein is to improve the performance of a wireless communications network in which multiple RH are operating.

According to an aspect of embodiments herein, the object is achieved by a method performed by a network node. The method is for handling delays related to Random Access, RA, preambles in a wireless communications network in which multiple Radio Head devices, RHs, are operating. Each respective RH out of the multiple RHs are connected to a baseband unit via a radio unit in a respective branch, and is serving at least one User Equipment, UE, from which RA preambles are to be received.

For each respective branch the network node configures a first delay to compensate for a measured time-of-arrival value in the branch,

The network node maps to each respective RH out of the multiple RHs, the RH’s related first delay, at least one RA preamble associated with the RH, and an interval in a detection window of an RA preamble receiver in the baseband unit. The interval is determined based on a delay between the RH and the baseband unit. The interval is a signal detection interval related to the at least one RA preamble.

When receiving a preamble signal in one of the intervals, the network node is deciding which first delay to use based on the mapped intervals.

According to another aspect of embodiments herein, the object is achieved by a network node configured to handling delays related to Random Access, RA, preambles in a wireless communications network in which multiple Radio Head devices, RHs, are operable. Each respective RH out of the multiple RHs are connectable to a baseband unit via a radio unit in a respective branch and is adapted to be serving at least one User Equipment, UE, from which RA preambles are to be received. The network node further being configured to:

For each respective branch configure a first delay to compensate for a measured time-of-arrival value in the branch, map to each respective RH out of the multiple RHs:

- the RH’s related first delay,

- at least one RA preamble associated with the RH, and

- an interval in a detection window of an RA preamble receiver in the baseband unit, which interval is adapted to be determined based on a delay between the RH and the baseband unit, and which interval is adapted to be a signal detection interval related to the at least one RA preamble, and when receiving a preamble signal in one of the intervals, decide which first delay to use based on the mapped intervals.

By checking the mapping, the network node is capable of decide which delay compensation to use for each specific RH, based on the mapped intervals when the network node receives a preamble signal in one of the intervals. This is instead of as prior art, using the same delay compensation for all RHs. This results in an improved performance of a wireless communications network in which multiple RH are operating.

Advantages of embodiments herein are e.g. that they improve the large delay issue and significantly improve flexibility and cost efficiency of e.g. indoor deployment.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples of embodiments herein are described in more detail with reference to attached drawings in which:

Figure 1 is a schematic block diagram illustrating embodiments of a wireless communications network.

Figure 2 is a flowchart depicting an embodiment of a method in a network node.

Figure 3 is a schematic block diagram illustrating an example scenario of embodiments herein.

Figure 4 is a schematic diagram illustrating an example of embodiments herein.

Figure 5 is a schematic diagram illustrating an example of embodiments herein.

Figure 6 is a schematic diagram illustrating an example of embodiments herein.

Figure 7 is a schematic block diagram illustrating embodiments of a network node.

Figure 8 schematically illustrates embodiments of a communication system.

Figure 9 is a generalized block diagram of embodiments of a UE.

Figure 10 is a generalized block diagram of embodiments of a network node.

Figure 11 is a generalized block diagram of embodiments of a host.

Figure 12 is a generalized block diagram of embodiments of a virtualization environment.

Figure 13 is a generalized block diagram of embodiments of a communication diagram of a host.

DETAILED DESCRIPTION

An example embodiment herein may comprise the following:

Multiple delays from the RHs to the baseband unit and their maximum RH-LIE delays are configured. An interval in the matched filter output of the RA preamble receiver is defined for each combination of RH and RA preamble generated from a root sequence.

In some embodiments, all intervals for all RHs are checked to identify any overlapping intervals.

If there is an overlap, extra delay(s) to one or several branches to the radio dot(s) is determined to avoid overlap.

The determined extra delays may then be implemented into the cabling or system in the involved branches.

As mentioned above, embodiments herein improve the large delay issue and significantly improve flexibility and cost efficiency of e.g. the indoor deployment. In more detail

Embodiments herein remove current product limitation of “maximum difference of the total length of fiber between Indoor Connect and RHs which may be 2.5 km.

The maximum supported round-trip time is significantly extended, corresponding to up to tens of km cell range, only limited by PRACH receiver sensitivity.

The delays of different RHs may be distributed almost arbitrary.

Examples of embodiments herein are e.g., further related to technical areas such as Random Access, Indoor Connect, Indoor Radio Unit, PRACH, Timing Advance.

Figure 1 is a schematic overview depicting a wireless communications network 100, such as e.g. a wireless communications network, wherein embodiments herein may be implemented. The communications network 100 comprises one or more RANs and one or more CNs. The communications network 100 may use 5G NR but may further use a number of other different technologies, such as, 6G, Wi-Fi, (LTE), LTE-Advanced, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile communications/enhanced Data rate for GSM Evolution (GSM/EDGE), or Ultra Mobile Broadband (UMB), just to mention a few possible implementations.

Network nodes, such as a network node 110 operate in the wireless communications network 100. Multiple RHs operate in the wireless communications network 100, such as e.g. a first RHs 111 , a second RH 112, a third RH 113, and a fourth RH 114. The RHs 111 , 112, 113, 114 may e.g. be a remote radio head device but may not be limited to it. It may e.g. be described as equivalent to an active antenna element. The network node 110 may comprise or be accessible to The RHs 111 , 112, 113, 114. Each respective RH out of the multiple RHs 111 , 112, 113, 114 may be connected to a baseband unit 130 via a respective radio unit such as e.g., a first radio unit 140 and/or a second radio unit 141 and possibly via an interconnect unit 145, in a respective branch. Each respective RH out of the multiple RHs 111 , 112, 113, 114 may serve at least one UE 121 , 122, 123, 124.

Each of the RHs 111, 112, 113, 114 and the network node 110 may be a transmission and reception point e.g. a radio access network node such as a base station, a radio base station, a NodeB, an evolved Node B (eNB, eNodeB, eNode B), an NR/g Node B (gNB), a part of an Indoor Radio Unit (IRU), an Open RAN (ORAN) node, a base transceiver station, a radio remote unit, an Access Point Base Station, a base station router, a transmission arrangement of a radio base station, a stand-alone access point, a Wireless Local Area Network (WLAN) access point, an Access Point Station (AP STA), an access controller, a UE acting as an access point or a peer in a Device to Device (D2D) communication, or any other network unit capable of communicating with a UE served by the network node 110 depending e.g. on the radio access technology and terminology used.

UEs, such as a first UE 121 , a second UE 122, a third UE 123 and a fourth UE 124 operate in the wireless communications network 100. The UEs 121, 122, 123, 124 may each e.g. be an NR device, a mobile station, a wireless terminal, an loT device, an loS device, an enhanced Machine Type Communication (eMTC) device, an NR RedCap device, a CAT-M device, a Vehicle-to-everything (V2X) device, Vehicle-to-Vehicle (V2V) device, a Vehicle-to-Pedestrian (V2P) device, a Vehicle-to-lnfrastructure (V2I) device, a Vehicle-to-Network (V2N) device, a Wi-Fi device, an LTE device, a non-access point (non-AP) STA, a STA, that communicates via a base station such as e.g. the network node 110, and one or more Access Networks (AN), e.g. RAN, to one or more core networks (CN). It should be understood by the skilled in the art that the term UE relates to a non-limiting term which means any UE, terminal, wireless communication terminal, user equipment, (D2D) terminal, or node e.g. smart phone, laptop, mobile phone, sensor, relay, mobile tablets or even a small base station communicating within a cell.

Methods herein may in one aspect be performed by the network node 110. As an alternative, a Distributed Node (DN) and functionality, e.g. comprised in a cloud 135 as shown in Figure 1, may be used for performing or partly performing the methods of embodiments herein.

A number of embodiments will now be described, some of which may be seen as alternatives, while some may be used in combination.

Figure 2 shows exemplary embodiments of a method performed by the network node 110. The method is for handling delays, such as e.g. the first delay and/or the extra delay, related to Random Access (RA) preambles in a wireless communications network 100 in which multiple Radio Head devices (RHs) 111 , 112, 113, 114 are operating. A delay when used herein is a delay of a signal, such as a RA preamble from one of the UEs 121, 122, 123, 124, because of its propagation from a transmitter towards a receiver and back again. The delay is different to different RHs. This is e.g., because of the different lengths, e.g., a connection or cable lengths, between the baseband unit 130 and the respective RH 111 , 112, 113, 114, and therefore the propagation takes different long time. These delays refer to the first delay and the extra delay described below. Each respective RH out of the multiple RHs 111, 112, 113, 114 are connected to a baseband unit 130 via a radio unit 140, 141 in a respective branch. Further, each respective RH out of the multiple RHs 111 , 112, 113, 114, is serving at least one LIE, 121, 122, 123, 124 from which RA preambles are to be received.

The method comprises the following actions, which actions may be taken in any suitable order. Optional actions are referred to as dashed boxes in Figure 2.

Action 200

According to some embodiments herein, the network node 110 determines a first delay between RH and the baseband unit for each branch. The delay may be determined through measurements. The wording “first delay” is simply used to differentiate the delay from the “extra delay” described below.

Action 201

According to embodiments herein, the network node 110 configures the first delay for each respective branch. This is to compensate for a measured time-of-arrival value in the respective branch. There may be different delay compensations for the different branches. In some embodiments, the configuring further comprises configuring a maximum delay from the RH to its served UE, 121, 122, 123, 124. A respective maximum delay from the RH to its served UE, 121 , 122, 123, 124 may be configured to determine a mapping between the RH and an interval in the detection window of an RA preamble receiver. The maximum delay is e.g. related to the length of the intervals and hence to any possible overlap of intervals. This will be described below.

Action 202

The network node maps to each respective RH out of the multiple RHs 111, 112, 113, 114 the following:

- The RH’s related first delay,

- at least one RA preamble associated with the RH, e.g. generated from one root sequence, and

- an interval in a detection window of an RA preamble receiver in the baseband unit 130. The interval is a signal detection interval related to the at least one RA preamble. Within this signal detection interval the RA preamble is assumed to be detected. Different RA preambles associated with different RHs are detectable in different intervals. So by knowing in which interval the respective RH associated RA preamble shall be detected, it is possible to know to which RH the preamble belongs when receiving an RA preamble.

The mapping may be performed by making a table such as a lookup table comprising, in each row line of the table, columns comprising the RH, the first delay, the RA preamble, and the interval in a detection window. This will be exemplified more later on.

The interval is determined based on the first delay between RH and the baseband unit 130. In some embodiments, the configuring of the first delay further comprises: configuring a maximum delay from the RH to its served UE, 121, 122, 123, 124. In these embodiments, the mapped interval is determined further based on the maximum delay.

The detection window may comprise a Physical Random-Access Channel (PRACH) a symbol length, or a part of a PRACH symbol length.

In some embodiments, multiple RA preambles are generated from a single root sequence. In these embodiments, there is one detection window per generated RA preamble.

Action 203 When receiving a preamble signal in one of the intervals, the network node 110 decides which first delay to use based on the mapped intervals.

In some embodiments, the deciding of which first delay to use based on the mapped intervals, further comprises deciding which RH out of the multiple RHs 111 , 112, 113, 114 the RA preamble relates to.

For example, an unknown RA preamble is received in the baseband unit 130 from one of the UEs. It is received in an interval. The network node 110 checks in which interval the RA preamble is received in among the mapped intervals, e.g., checks in the lookup table. The network node 110 then retrieves which RH the interval corresponds to, and which first delay to use for that RA preamble.

Action 204

In some example scenarios, there may be overlapping intervals in a detection window. In some embodiments, the network node 110 decides whether or not there are any overlapping intervals in a detection window, among the intervals of the respective multiple RHs 111, 112, 113, 114. The detection window is a time detection window of RA preambles.

Action 205

In some of these embodiments, when there are overlapping intervals, the network node 110 determines at least one extra delay to one or more respective branches towards at least one of the RHs involved in the identified overlapping intervals. This is to eliminate the overlapping of the identified intervals.

The extra delay may then be added to the first delay.

The delay compensation is recalculated based on the new total delay comprising the first delay and the extra delay.

Action 206

In some embodiments, the network node 110 implements the determined at least one extra delay, e.g. added to the first delay, into connections, of said one or more respective branches. The connections may e.g. be represented by anyone or more out of cable and fiber.

In some embodiments when no overlapping intervals, the network node 110 implements the respective first delay, into connections, of said one or more respective branches. Embodiments herein such as the embodiments mentioned above will now be further described and exemplified. The text below is applicable to and may be combined with any suitable embodiment described above.

Delay Illustration

Figure 3 depicts delays in an example deployment of the wireless communication network 100 according to an example. Figure 3 depicts that the UEs, 121 , 122, 123, 124 served by different RHs 111 , 112, 113, 114 have different delays to the baseband unit 130. The delays result in different round-trip times. For example, the first UE 121 has a round-trip time and the third UE 123 has a round-trip time of As described above, The detection window shows the range of delays that may be detected from a matched filter output and has duration T_symb = 33.3 ps for the random-access preamble subcarrier spacing . For round-trip times T larger than the detection window the estimated round-trip time will be T = T mod T_symb-

Figure 4 depicts signal timings in detection window without extra delay according to some example embodiments herein. In Figure 4 timings of all the UEs 121 , 122, 123, 124 signals from all the RHs 111 , 112, 113, 114, including the air propagation delays from the UEs 121 , 122, 123, 124 to their respective RHs 111 , 112, 113, 114. All UEs 121 , 122, 123, 124 in Figure 3 have a delay distribution at the baseband unit 130 shown as a corresponding interval in Figure 4.

In some first embodiments, focus on the intervals related to the third UE 123 and the second UE 122 intervals in Figure 4 and take them as example. The intervals related to the third UE 123 and the second UE 122 do not overlap, therefore the two fixed roundtrip times between the RH and the baseband unit 130 i.e., may be configured in the baseband unit 130 as parameters to compensate for the two RH 112 113 delays. In more detail, if the two fixed delays are measured as then the delay value and the interval 7^, i.e., the range of measured delays, T, in baseband unit 130 are configured as parameters, see the mapping according to Action 202 represented by Table 1 below. The configured corrections are give as long as the interval 7^- does not wrap around, i.e., as long as mod ^symb < ( ij + Ttj ) mod T_Sy_mb.

Table 1

If a round-trip time estimate T falls into any configured range of round-trip times in table 1, the baseband unit 130 will use the corresponding correction to compensate the measured TA value T and send the new TA value in the Random Access Response message (message 2). Since the intervals related to the third UE 123 and the second UE 122 do not overlap, the timing advance compensation will be correct if all delay measurements and uncertainties are correct. Note in this example, Delay 2 is 50 ps larger than Delay 1. However, the green and red intervals show up in the same detection window and their distance becomes (160-110) mod 33.3 = 16.7 ps instead, because of the modulo operation.

In some other example scenarios, a worse case might appear, namely that different intervals overlap even if they correspond to very different delays. The coverage of the fourth RH 114 where the fourth UE 124 is located, corresponds to the dashed-line UE 114 interval in time domain, while within the detection window it will show up as the solid-line UE 114 interval which overlaps the first UE 120 interval. The solution for the first embodiments described above does not work correctly anymore. This is since there is not a one-to-one mapping between the measured round-trip times T and the intervals for the different RHs 111, 112, 113, 114, the network node 110 cannot determine for the baseband unit 130 what correction delay to use. See the mapping according to Action 202 represented by Table 2 below.

Table 2

In such case (Case 2), an additional solution is provided according to embodiments herein. See Figure 5. This relates to Actions 204-206 as described above, which may in an example comprise to:

Determine if there exists any overlap among intervals in the detection window.

Among all intervals, determine which one(s) should be delayed even further, with the extra delay.

Determine, also referred to as calculate, extra delay(s) for the selected interval(s).

Implement the extra delays.

Use the new total delay(s) to determine the compensation for the TA command, i.e., in the table 2 above use the entry “Delay 3 Case 2” instead of “Delay 3”.

The purpose is to separate all intervals in the detection window such that the intervals are not overlapping, and such that adjacent intervals have some margin to give robustness against delay measurement errors or delay uncertainties. The extra delay is preferred to be small for easier and more cost-efficient implementation. Figure 5 depicts signal timings in detection window after introducing an extra delay, i.e., component “D”. In Figure 5 for example, it can be seen that either the UE 114 interval or the first UE 120 interval needs to be further delayed. Extra delay is added to the UE 114 interval i in this example. A new entry “Delay 3 Case 2” is added and entry “Delay 3” needs to be removed. In practice, the extra delay may be realized by e.g., a longer fiber (fiber cable is very cheap), other delay-line solutions, or extra logic in the RH and/or the radio unit.

In many cases the extra delay does not need to be very precise, as long as the amount of delay can be measured.

Multiple preambles per root sequence

RA preamble processing for different RA preambles generated from the same root sequence typically share some parts, such as a matched filter. For that reason, and for root sequence planning, it is beneficial to generate multiple preambles from a single root sequence via cyclic shifts. Such cyclic shifts are determined by the parameter N_cs. In such a case there is one detection window per preamble as in Figure 6, i.e., to each preamble there is an interval in the matched filter output that corresponds to the detection window for preamble p with start at T_p and with duration T_det determined by the RA preamble symbol time T_symb, the RA preamble sequence length, and

Figure 6 depicts signal timings in multiple detection windows i.e. Ncs>0 (all preambles from a certain dot will have similar relative timing in the detection windows)

For such a receiver to work for the indoor connect scenario, some embodiments ensure that for the delays between RHs 111, 112, 113, 114 and baseband unit 130, Ttj , such Jij fit within the range of the first detection window, e [0, T_det] while keeping all intervals non-overlapping between radio dots. Then the radio dot and hence TA correction is obtained from the interval J;, that contains T as described above for a single preamble per root sequence.

An alternative is to define intervals: for all RA preambles and for all radio dots. Just for the case of a single preamble per root sequence, all the intervals must be non-overlapping. If it is not the case extra delay is added to one or several RHs 111, 112, 113, 114 until all intervals are nonoverlapping.

When a peak in the interval is detected with delay T within the interval, it is checked for what interval The RA preamble detected is then p and the corrected TA value is where T_Pois the beginning of the detection interval that contains

For example, for and for a minimum non zero cyclic shift of 11.1 ps the values of T_p will be From the values of one obtains T_Po = 11.1 ps, which is the largest value of T_p less than or equal to 20 ps.

If the preamble receiver detects a preamble at the third detection window starting at 22.2 μs with delay T = 9.4 ps then T_TA = 9.4 + 100 + 22.2 — 11.1 = 120.5 ps.

Embodiments herein are valid for Cloud RAN as well, because the baseband logic part is per cell and is not limited by any signaling/interface.

Embodiments herein are also valid for O-RAN as well, because the baseband logic part is not limited by any signaling and/or interface.

To perform the method actions above, network node 110 is configured to handle delays related to RA preambles in the wireless communications network 100 in which multiple RHs 111, 112, 113, 114 are operable. Each respective RH out of the multiple RHs 111 , 112, 113, 114 are connectable to the baseband unit 130 via a radio unit 140, 141 in a respective branch, and is adapted to be serving at least one UE, 121 , 122, 123, 124 from which RA preambles are to be received. The network node 110 may comprise an arrangement depicted in Figure 7.

The network node 110 is further configured to, for each respective branch configure a first delay to compensate for a measured time-of-arrival value in the branch. The network node 110 is further configured to map to each respective RH out of the multiple RHs 111, 112, 113, 114:

- The RH’s related first delay,

- at least one RA preamble associated with the RH, and

- an interval in a detection window of an RA preamble receiver in the baseband unit 130. The interval is determined based on the first delay between the RH and the baseband unit, and which interval is a signal detection interval related to the at least one RA preamble.

The network node 110 is further configured to when receiving a preamble signal in one of the intervals, decide which first delay to use based on the mapped intervals.

In some embodiments, multiple RA preambles are generated from a single root sequence. In these embodiments, there may be one detection window per generated RA preamble.

In some embodiments, the network node 110 is further being configured to configure a maximum delay from the RH to its served UE, 121, 122, 123, 124, and

In these embodiments, the mapped interval may be adapted to be determined further based on the maximum delay.

The network node 110 may further configured to decide which first delay to use based on the mapped intervals, by deciding which RH out of the multiple RHs 111 , 112, 113, 114 the RA preamble relates to.

The network node 110 may further configured to decide whether or not there are any overlapping intervals in a detection window, among the intervals of the respective multiple RHs 111, 112, 113, 114, which detection window is a time detection window of RA preambles.

The network node 110 may further configured to, when there are overlapping intervals, determine at least one extra delay to one or more respective branches towards at least one of the RHs involved in the identified overlapping intervals, to eliminate the overlapping of the identified intervals. The extra delay may be adapted to be added to the first delay to produce a new total delay. The delay compensation may be recalculated based on the new total delay.

The network node 110 may further configured to implement the determined at least one extra delay into connections of said one or more respective branches. The detection window may be adapted to comprise a PRACH symbol length, or a part of a PRACH symbol length.

The network node 110 may comprise an arrangement depicted in Figure 7. The network node 110 may comprise an input and output interface 700 configured to communicate in the wireless communications network 100, e.g., with the multiple RHs 111 , 112, 113, 114, the baseband unit 130, the radio units 140, 141 and/or the at least one UE, 121, 122, 123, 124. The input and output interface 700 may comprise a wireless receiver not shown, and a wireless transmitter not shown.

The embodiments herein may be implemented through a processor or one or more processors, such as the processor 710 of a processing circuitry in the network node 110 depicted in Figure 7 together with computer program code for performing the functions and actions of the embodiments herein. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code for performing the embodiments herein when being loaded into the network node 110. One such carrier may be in the form of a CD ROM disc. It is however feasible with other data carriers such as a memory stick. The computer program code may furthermore be provided as pure program code on a server and downloaded to the network node 110.

The network node 110 may further comprise a memory 720 comprising one or more memory units. The memory 720 comprises instructions executable by the processor in the network node 110. The memory 720 are arranged to be used to store e.g., delays, information, indications, data, configurations, communication data, and applications to perform the methods herein when being executed in the network node 110.

In some embodiments, a computer program 730 comprises instructions, which when executed by the at least one processor 710, cause the at least one processor of first network node 110 to perform the actions above.

In some embodiments, a carrier 740 comprises the computer program 730, wherein the carrier 740 is one of an electronic signal, an optical signal, an electromagnetic signal, a magnetic signal, an electric signal, a radio signal, a microwave signal, or a computer- readable storage medium.

Those skilled in the art will appreciate that units in the network node 110 described above may refer to a combination of analog and digital circuits, and/or one or more processors configured with software and/or firmware, e.g. stored in the network node 110, that when executed by the one or more processors such as the processors described above. One or more of these processors, as well as the other digital hardware, may be included in a single Application-Specific Integrated Circuitry ASIC, or several processors and various digital hardware may be distributed among several separate components, whether individually packaged or assembled into a System-on-a-Chip (SoC).

ADDITIONAL EXPLANATION

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

Figure 8 shows an example of a communication system QQ100 in accordance with some embodiments.

In the example, the communication system QQ100 includes a telecommunication network QQ102 that includes an access network QQ104, such as a radio access network (RAN), and a core network QQ106, which includes one or more core network nodes QQ108. The access network QQ104 includes one or more access network nodes, such as network nodes QQ110a and QQ110b (one or more of which may be generally referred to as network nodes QQ110), or any other similar 3rd Generation Partnership Project (3GPP) access nodes or non-3GPP access points. Moreover, as will be appreciated by those of skill in the art, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network QQ102 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network QQ102 that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network QQ102, including one or more network nodes QQ110 and/or core network nodes QQ108.

Examples of an ORAN network node include an open radio unit (O-RU), an open distributed unit (O-DU), an open central unit (O-CU), including an O-CU control plane (O- CU-CP) or an O-CU user plane (O-CU-UP), a RAN intelligent controller (near-real time or non-real time) hosting software or software plug-ins, such as a near-real time control application (e.g., xApp) or a non-real time control application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an ORAN specification). The network node may support a specification by, for example, supporting an interface defined by the ORAN specification, such as an A1 , F1 , W1, E1 , E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. Moreover, an ORAN access node may be a logical node in a physical node. Furthermore, an ORAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an 0-2 interface defined by the O-RAN Alliance or comparable technologies. The network nodes QQ110 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs QQ112a, QQ112b, QQ112c, and QQ112d (one or more of which may be generally referred to as UEs QQ112) to the core network QQ106 over one or more wireless connections.

Example wireless communications over a wireless connection include transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system QQ100 may include any number of wired or wireless networks, network nodes, UEs, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections. The communication system QQ100 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system.

The UEs QQ112 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and/or operable to communicate wirelessly with the network nodes QQ110 and other communication devices. Similarly, the network nodes QQ110 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs QQ112 and/or with other network nodes or equipment in the telecommunication network QQ102 to enable and/or provide network access, such as wireless network access, and/or to perform other functions, such as administration in the telecommunication network QQ102.

In the depicted example, the core network QQ106 connects the network nodes QQ110 to one or more hosts, such as host QQ116. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network QQ106 includes one more core network nodes (e.g., core network node QQ108) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and/or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node QQ108. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (ALISF), Subscription Identifier Deconcealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and/or a User Plane Function (UPF).

The host QQ116 may be under the ownership or control of a service provider other than an operator or provider of the access network QQ104 and/or the telecommunication network QQ102, and may be operated by the service provider or on behalf of the service provider. The host QQ116 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio/video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

As a whole, the communication system QQ100 of Figure 8 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and/or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and/or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox.

In some examples, the telecommunication network QQ102 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network QQ102 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network QQ102. For example, the telecommunications network QQ102 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and/or Massive Machine Type Communication (mMTC)/Massive loT services to yet further UEs.

In some examples, the UEs QQ112 are configured to transmit and/or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network QQ104 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network QQ104. Additionally, a UE may be configured for operating in single- or multi- RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

In the example, the hub QQ114 communicates with the access network QQ104 to facilitate indirect communication between one or more UEs (e.g., UE QQ112c and/or QQ112d) and network nodes (e.g., network node QQ110b). In some examples, the hub QQ114 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub QQ114 may be a broadband router enabling access to the core network QQ106 for the UEs. As another example, the hub QQ114 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes QQ110, or by executable code, script, process, or other instructions in the hub QQ114. As another example, the hub QQ114 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub QQ114 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub QQ114 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub QQ114 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub QQ114 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy loT devices.

The hub QQ114 may have a constant/persistent or intermittent connection to the network node QQ110b. The hub QQ114 may also allow for a different communication scheme and/or schedule between the hub QQ114 and UEs (e.g., UE QQ112c and/or QQ112d), and between the hub QQ114 and the core network QQ106. In other examples, the hub QQ114 is connected to the core network QQ106 and/or one or more UEs via a wired connection. Moreover, the hub QQ114 may be configured to connect to an M2M service provider over the access network QQ104 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes QQ110 while still connected via the hub QQ114 via a wired or wireless connection. In some embodiments, the hub QQ114 may be a dedicated hub - that is, a hub whose primary function is to route communications to/from the UEs from/to the network node QQ110b. In other embodiments, the hub QQ114 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node QQ110b, but which is additionally capable of operating as a communication start and/or end point for certain data channels.

Figure 9 shows a UE QQ200 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged and/or operable to communicate wirelessly with network nodes and/or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop- embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle, vehicle-mounted or vehicle embedded/integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-loT) UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE.

A UE may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

The UE QQ200 includes processing circuitry QQ202 that is operatively coupled via a bus QQ204 to an input/output interface QQ206, a power source QQ208, a memory QQ210, a communication interface QQ212, and/or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 9. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

The processing circuitry QQ202 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory QQ210. The processing circuitry QQ202 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry QQ202 may include multiple central processing units (CPUs).

In the example, the input/output interface QQ206 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and/or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE QQ200. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device. In some embodiments, the power source QQ208 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source QQ208 may further include power circuitry for delivering power from the power source QQ208 itself, and/or an external power source, to the various parts of the UE QQ200 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source QQ208. Power circuitry may perform any formatting, converting, or other modification to the power from the power source QQ208 to make the power suitable for the respective components of the UE QQ200 to which power is supplied.

The memory QQ210 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory QQ210 includes one or more application programs QQ214, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data QQ216. The memory QQ210 may store, for use by the UE QQ200, any of a variety of various operating systems or combinations of operating systems.

The memory QQ210 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and/or ISIM, other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUlCC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’ The memory QQ210 may allow the UE QQ200 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory QQ210, which may be or comprise a device-readable storage medium. The processing circuitry QQ202 may be configured to communicate with an access network or other network using the communication interface QQ212. The communication interface QQ212 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna QQ222. The communication interface QQ212 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter QQ218 and/or a receiver QQ220 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter QQ218 and receiver QQ220 may be coupled to one or more antennas (e.g., antenna QQ222) and may share circuit components, software or firmware, or alternatively be implemented separately.

In the illustrated embodiment, communication functions of the communication interface QQ212 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and/or standards, such as IEEE 802.11 , Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol/internet protocol (TCP/IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface QQ212, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).

As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input.

A UE, when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an loT device are a device which is or which is embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door/window sensor, a flood/moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smartwatch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an loT device comprises circuitry and/or software in dependence of the intended application of the loT device in addition to other components as described in relation to the UE QQ200 shown in Figure 9.

As yet another specific example, in an loT scenario, a UE may represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another UE and/or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-loT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation.

In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’s speed. The first and/or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.

Figure 10 shows a network node QQ300 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a UE and/or with other network nodes or equipment, in a telecommunication network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)), O- RAN nodes or components of an O-RAN node (e.g., O-RU, O-DU, O-CU).

Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units, distributed units (e.g., in an O-RAN access node) and/or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi- cel l/multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and/or Minimization of Drive Tests (MDTs).

The network node QQ300 includes a processing circuitry QQ302, a memory QQ304, a communication interface QQ306, and a power source QQ308. The network node QQ300 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node QQ300 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node QQ300 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory QQ304 for different RATs) and some components may be reused (e.g., a same antenna QQ310 may be shared by different RATs). The network node QQ300 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node QQ300, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node QQ300.

The processing circuitry QQ302 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node QQ300 components, such as the memory QQ304, to provide network node QQ300 functionality.

In some embodiments, the processing circuitry QQ302 includes a system on a chip (SOC). In some embodiments, the processing circuitry QQ302 includes one or more of radio frequency (RF) transceiver circuitry QQ312 and baseband processing circuitry QQ314. In some embodiments, the radio frequency (RF) transceiver circuitry QQ312 and the baseband processing circuitry QQ314 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry QQ312 and baseband processing circuitry QQ314 may be on the same chip or set of chips, boards, or units.

The memory QQ304 may comprise any form of volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device- readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by the processing circuitry QQ302. The memory QQ304 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and/or other instructions capable of being executed by the processing circuitry QQ302 and utilized by the network node QQ300. The memory QQ304 may be used to store any calculations made by the processing circuitry QQ302 and/or any data received via the communication interface QQ306. In some embodiments, the processing circuitry QQ302 and memory QQ304 is integrated.

The communication interface QQ306 is used in wired or wireless communication of signaling and/or data between a network node, access network, and/or UE. As illustrated, the communication interface QQ306 comprises port(s)/terminal(s) QQ316 to send and receive data, for example to and from a network over a wired connection. The communication interface QQ306 also includes radio front-end circuitry QQ318 that may be coupled to, or in certain embodiments a part of, the antenna QQ310. Radio front-end circuitry QQ318 comprises filters QQ320 and amplifiers QQ322. The radio front-end circuitry QQ318 may be connected to an antenna QQ310 and processing circuitry QQ302. The radio front-end circuitry may be configured to condition signals communicated between antenna QQ310 and processing circuitry QQ302. The radio front-end circuitry QQ318 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry QQ318 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters QQ320 and/or amplifiers QQ322. The radio signal may then be transmitted via the antenna QQ310. Similarly, when receiving data, the antenna QQ310 may collect radio signals which are then converted into digital data by the radio front-end circuitry QQ318. The digital data may be passed to the processing circuitry QQ302. In other embodiments, the communication interface may comprise different components and/or different combinations of components.

In certain alternative embodiments, the network node QQ300 does not include separate radio front-end circuitry QQ318, instead, the processing circuitry QQ302 includes radio front-end circuitry and is connected to the antenna QQ310. Similarly, in some embodiments, all or some of the RF transceiver circuitry QQ312 is part of the communication interface QQ306. In still other embodiments, the communication interface QQ306 includes one or more ports or terminals QQ316, the radio front-end circuitry QQ318, and the RF transceiver circuitry QQ312, as part of a radio unit (not shown), and the communication interface QQ306 communicates with the baseband processing circuitry QQ314, which is part of a digital unit (not shown).

The antenna QQ310 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. The antenna QQ310 may be coupled to the radio front-end circuitry QQ318 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In certain embodiments, the antenna QQ310 is separate from the network node QQ300 and connectable to the network node QQ300 through an interface or port.

The antenna QQ310, communication interface QQ306, and/or the processing circuitry QQ302 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by the network node. Any information, data and/or signals may be received from a UE, another network node and/or any other network equipment. Similarly, the antenna QQ310, the communication interface QQ306, and/or the processing circuitry QQ302 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and/or signals may be transmitted to a UE, another network node and/or any other network equipment.

The power source QQ308 provides power to the various components of network node QQ300 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source QQ308 may further comprise, or be coupled to, power management circuitry to supply the components of the network node QQ300 with power for performing the functionality described herein. For example, the network node QQ300 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source QQ308. As a further example, the power source QQ308 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

Embodiments of the network node QQ300 may include additional components beyond those shown in Figure 10 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, the network node QQ300 may include user interface equipment to allow input of information into the network node QQ300 and to allow output of information from the network node QQ300. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node QQ300.

Figure 11 is a block diagram of a host QQ400, which may be an embodiment of the host QQ116 of Figure 8, in accordance with various aspects described herein. As used herein, the host QQ400 may be or comprise various combinations hardware and/or software, including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host QQ400 may provide one or more services to one or more UEs.

The host QQ400 includes processing circuitry QQ402 that is operatively coupled via a bus QQ404 to an input/output interface QQ406, a network interface QQ408, a power source QQ410, and a memory QQ412. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures QQ2 and QQ3, such that the descriptions thereof are generally applicable to the corresponding components of host QQ400.

The memory QQ412 may include one or more computer programs including one or more host application programs QQ414 and data QQ416, which may include user data, e.g., data generated by a UE for the host QQ400 or data generated by the host QQ400 for a UE. Embodiments of the host QQ400 may utilize only a subset or all of the components shown. The host application programs QQ414 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAG, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, heads-up display systems). The host application programs QQ414 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host QQ400 may select and/or indicate a different host for over-the-top services for a UE. The host application programs QQ414 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc. Figure 12 is a block diagram illustrating a virtualization environment QQ500 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments QQ500 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized. In some embodiments, the virtualization environment QQ500 includes components defined by the O-RAN Alliance, such as an O-Cloud environment orchestrated by a Service Management and Orchestration Framework via an 0-2 interface.

Applications QQ502 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment Q400 to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein.

Hardware QQ504 includes processing circuitry, memory that stores software and/or instructions executable by hardware processing circuitry, and/or other hardware devices as described herein, such as a network interface, input/output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers QQ506 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs QQ508a and QQ508b (one or more of which may be generally referred to as VMs QQ508), and/or perform any of the functions, features and/or benefits described in relation with some embodiments described herein. The virtualization layer QQ506 may present a virtual operating platform that appears like networking hardware to the VMs QQ508.

The VMs QQ508 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer QQ506. Different embodiments of the instance of a virtual appliance QQ502 may be implemented on one or more of VMs QQ508, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.

In the context of NFV, a VM QQ508 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs QQ508, and that part of hardware QQ504 that executes that VM, be it hardware dedicated to that VM and/or hardware shared by that VM with others of the VMs, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs QQ508 on top of the hardware QQ504 and corresponds to the application QQ502.

Hardware QQ504 may be implemented in a standalone network node with generic or specific components. Hardware QQ504 may implement some functions via virtualization. Alternatively, hardware QQ504 may be part of a larger cluster of hardware (e.g. such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration QQ510, which, among others, oversees lifecycle management of applications QQ502. In some embodiments, hardware QQ504 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station. In some embodiments, some signaling can be provided with the use of a control system QQ512 which may alternatively be used for communication between hardware nodes and radio units.

Figure 13 shows a communication diagram of a host QQ602 communicating via a network node QQ604 with a UE QQ606 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as a UE QQ112a of Figure 8 and/or UE QQ200 of Figure 9), network node (such as network node QQ110a of Figure 8 and/or network node QQ300 of Figure 10), and host (such as host QQ116 of Figure 8 and/or host QQ400 of Figure 11) discussed in the preceding paragraphs will now be described with reference to Figure 13.

Like host QQ400, embodiments of host QQ602 include hardware, such as a communication interface, processing circuitry, and memory. The host QQ602 also includes software, which is stored in or accessible by the host QQ602 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE QQ606 connecting via an over-the-top (OTT) connection QQ650 extending between the UE QQ606 and host QQ602. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection QQ650.

The network node QQ604 includes hardware enabling it to communicate with the host QQ602 and UE QQ606. The connection QQ660 may be direct or pass through a core network (like core network QQ106 of Figure 8) and/or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet.

The UE QQ606 includes hardware and software, which is stored in or accessible by UE QQ606 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE QQ606 with the support of the host QQ602. In the host QQ602, an executing host application may communicate with the executing client application via the OTT connection QQ650 terminating at the UE QQ606 and host QQ602. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection QQ650 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection QQ650.

The OTT connection QQ650 may extend via a connection QQ660 between the host QQ602 and the network node QQ604 and via a wireless connection QQ670 between the network node QQ604 and the UE QQ606 to provide the connection between the host QQ602 and the UE QQ606. The connection QQ660 and wireless connection QQ670, over which the OTT connection QQ650 may be provided, have been drawn abstractly to illustrate the communication between the host QQ602 and the UE QQ606 via the network node QQ604, without explicit reference to any intermediary devices and the precise routing of messages via these devices.

As an example of transmitting data via the OTT connection QQ650, in step QQ608, the host QQ602 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE QQ606. In other embodiments, the user data is associated with a UE QQ606 that shares data with the host QQ602 without explicit human interaction. In step QQ610, the host QQ602 initiates a transmission carrying the user data towards the UE QQ606. The host QQ602 may initiate the transmission responsive to a request transmitted by the UE QQ606. The request may be caused by human interaction with the UE QQ606 or by operation of the client application executing on the UE QQ606. The transmission may pass via the network node QQ604, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step QQ612, the network node QQ604 transmits to the UE QQ606 the user data that was carried in the transmission that the host QQ602 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step QQ614, the UE QQ606 receives the user data carried in the transmission, which may be performed by a client application executed on the UE QQ606 associated with the host application executed by the host QQ602.

In some examples, the UE QQ606 executes a client application which provides user data to the host QQ602. The user data may be provided in reaction or response to the data received from the host QQ602. Accordingly, in step QQ616, the UE QQ606 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input/output interface of the UE QQ606. Regardless of the specific manner in which the user data was provided, the UE QQ606 initiates, in step QQ618, transmission of the user data towards the host QQ602 via the network node QQ604. In step QQ620, in accordance with the teachings of the embodiments described throughout this disclosure, the network node QQ604 receives user data from the UE QQ606 and initiates transmission of the received user data towards the host QQ602. In step QQ622, the host QQ602 receives the user data carried in the transmission initiated by the UE QQ606.

One or more of the various embodiments improve the performance of OTT services provided to the UE QQ606 using the OTT connection QQ650, in which the wireless connection QQ670 forms the last segment. More precisely, the teachings of these embodiments may improve the latency and thereby provide benefits such as improved flexibility and cost efficiency

In an example scenario, factory status information may be collected and analyzed by the host QQ602. As another example, the host QQ602 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host QQ602 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host QQ602

Claims

may store surveillance video uploaded by a UE. As another example, the host QQ602 may store or control access to media content such as video, audio, VR or AR which it can broadcast, multicast or unicast to UEs. As other examples, the host QQ602 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing and/or transmitting data. In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection QQ650 between the host QQ602 and UE QQ606, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection may be implemented in software and hardware of the host QQ602 and/or UE QQ606. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection QQ650 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection QQ650 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node QQ604. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency and the like, by the host QQ602. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection QQ650 while monitoring propagation times, errors, etc. Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and/or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware. In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and/or by end users and a wireless network generally. When using the word "comprise" or “comprising” it shall be interpreted as nonlimiting, i.e. meaning "consist at least of". The embodiments herein are not limited to the preferred embodiments described above. Various alternatives, modifications and equivalents may be used. CLAIMS

1. A method performed by a network node (110) for handling delays related to Random Access, RA, preambles in a wireless communications network (100) in which multiple Radio Head devices, RHs, (111 , 112, 113, 114) are operating, wherein each respective RH out of the multiple RHs (111 , 112, 113, 114) are connected to a baseband unit (130) via a radio unit (140, 141) in a respective branch, and is serving at least one User Equipment, UE, (121 , 122, 123, 124) from which RA preambles are to be received, the method comprising: for each respective branch configuring (201) a first delay to compensate for a measured time-of-arrival value in the branch, mapping (202) to each respective RH out of the multiple RHs (111, 112, 113, 114):

- the RH’s related first delay,

- at least one RA preamble associated with the RH, and

- an interval in a detection window of an RA preamble receiver in the baseband unit (130), which interval is determined based on the first delay between the RH and the baseband unit, and which interval is a signal detection interval related to the at least one RA preamble, when receiving a preamble signal in one of the intervals, deciding (203) which first delay to use based on the mapped intervals.

2. The method according to claim 1 , wherein multiple RA preambles are generated from a single root sequence, and wherein there is one detection window per generated RA preamble.

3. The method according to according to any of the claims 1-2, wherein: the configuring (201) of the first delay further comprises: configuring a maximum delay from the RH to its served UE, (121 , 122, 123, 124), and wherein the mapped interval is determined further based on the maximum delay.

4. The method according to any of the claims 1-3, wherein the deciding (203) of which first delay to use based on the mapped intervals, further comprises deciding which RH out of the multiple RHs (111 , 112, 113, 114) the RA preamble relates to.

5. The method according to any of the claims 1-4, further comprising: deciding (204), whether or not there are any overlapping intervals in a detection window, among the intervals of the respective multiple RHs (111, 112, 113, 114), which detection window is a time detection window of RA preambles.

6. The method according to claim 5, further comprising: when there are overlapping intervals, determining (205) at least one extra delay to one or more respective branches towards at least one of the RHs involved in the identified overlapping intervals, to eliminate the overlapping of the identified intervals.

7. The method according to claim 6, wherein the extra delay is added to the first delay.

8. The method according to any of the claims 5-7, further comprising: implementing (206) the determined at least one extra delay into connections of said one or more respective branches.

9. The method according to any of the claims 5-8, wherein the detection window comprises a Physical Random Access Channel, PRACH, symbol length, or a part of a PRACH symbol length.

10. A computer program (730) comprising instructions, which when executed by a processor (710), causes the processor (710) to perform actions according to any of the claims 1-9.

11. A carrier (740) comprising the computer program (730) of claim 10, wherein the carrier (740) is one of an electronic signal, an optical signal, an electromagnetic signal, a magnetic signal, an electric signal, a radio signal, a microwave signal, or a computer-readable storage medium.

12. A network node (110) configured to handle delays related to Random Access, RA, preambles in a wireless communications network (100) in which multiple Radio Head devices, RHs, (111, 112, 113, 114) are operable, wherein each respective RH out of the multiple RHs (111 , 112, 113, 114) are connectable to a baseband unit (130) via a radio unit (140, 141) in a respective branch, and is adapted to be serving at least one User Equipment, UE, (121, 122, 123, 124) from which RA preambles are to be received, the network node (110) further being configured to: for each respective branch configure a first delay to compensate for a measured time-of-arrival value in the branch, map to each respective RH out of the multiple RHs (111 , 112, 113, 114)

- the RH’s related first delay,

- at least one RA preamble associated with the RH, and

- an interval in a detection window of an RA preamble receiver in the baseband unit (130), which interval is determined based on the first delay between the RH and the baseband unit, and which interval is a signal detection interval related to the at least one RA preamble, and when receiving a preamble signal in one of the intervals, decide which first delay to use based on the mapped intervals.

13. The network node (110) according to claim 12, wherein multiple RA preambles are adapted to be generated from a single root sequence, and wherein there is adapted to be one detection window per generated RA preamble.

14. The network node (110) according to any of the claims 12-13, further being configured to: configure the first delay further comprises: configure a maximum delay from the RH to its served UE, (121 , 122, 123, 124), and wherein the mapped interval is adapted to be determined further based on the maximum delay.

15. The network node (110) according to any of the claims 12-14, further being configured to: decide which first delay to use based on the mapped intervals, by deciding which RH out of the multiple RHs (111, 112, 113, 114) the RA preamble relates to.

16. The network node (110) according to any of the claims 12-15, further being configured to: decide whether or not there are any overlapping intervals in a detection window, among the intervals of the respective multiple RHs (111 , 112, 113, 114), which detection window is a time detection window of RA preambles,

17. The network node (110) according to claim 16, further being configured to: when there are overlapping intervals, determine at least one extra delay to one or more respective branches towards at least one of the RHs involved in the identified overlapping intervals, to eliminate the overlapping of the identified intervals.

18. The network node (110) according to claim 17, wherein the extra delay is adapted to be added to the first delay.

19. The network node (110) according to any of the claims 12-18, further being configured to: implement the determined at least one extra delay into connections of said one or more respective branches.

20. The network node (110) according to any of the claims 12-19, wherein the detection window is adapted to comprise a Physical Random Access Channel, PRACH, symbol length, or a part of a PRACH symbol length.