Phase compensation for partially-overlapped reference signal frequency hopping

Abstract

Methods are disclosed for phase compensation for partially overlapped reference signal frequency hopping and related measurement and reporting. In one embodiment, a method performed by a first node of a wireless communication system comprises performing measurements of a target narrowband reference signal from a second node of the wireless communication system, in accordance with a frequency hopping pattern. Then, the first node accumulates a wideband reference signal measurement based on the measurements of the target narrowband reference signal in a plurality of frequency hops of the frequency hopping pattern, by applying a phase rotation to the measurement(s) performed for one of a pair of frequency hops that are adjacent in frequency among the plurality of frequency hops.

Description

PHASE COMPENSATION FOR PARTIALLY-OVERLAPPED REFERENCE SIGNAL FREQUENCY HOPPING FIELD OF THE INVENTION

[0001] The present disclosure relates to a wireless communication network and, more specifically, to frequency-hopping based transmission and reception of reference signals in a wireless communication network. BACKGROUND

[0002] For Release 18, the 3rdGeneration Partnership Project (3GPP) is discussing New Radio (NR) positioning with potential enhancements for Reduced Capability (RedCap) User Equipment (UE) (i.e., “RedCap UE”) positioning in which the maximum bandwidth of a RedCap UE is 20 Megahertz (MHz) in Frequency Range 1 (FR1) and 100MHz in Frequency Range 2 (FR2). The solutions are uplink Sounding Reference Signal (SRS) frequency hopping and downlink Positioning Reference Signal (PRS) frequency hopping beyond the maximum bandwidth of the RedCap UE, for the RedCap UE positioning accuracy improvement. More specifically, it has been agreed in 3GPP to support receive (Rx) frequency hopping for downlink PRS receptions for RedCap UEs where a RedCap UE performs a wideband scan (i.e., perform downlink PRS measurements over a bandwidth that is greater than the maximum RedCap UE bandwidth) using Rx frequency hopping either across multiple slots (i.e., inter-slot Rx frequency hopping) or within a single slot (i.e., intra-slot Rx frequency hopping). In a similar manner, it has been agreed to support transmit (Tx) frequency hopping for uplink SRS transmissions for RedCap UEs.

[0003] It has also been agreed in 3GPP that the SRS for positioning Tx frequency hopping is configured within one SRS for positioning resource, and the frequency hopping pattern is configured with overlapping or non-overlapping frequency hops. For overlapping frequency hops i.e., two adjacent frequency hops overlap in the frequency domain, they may or may not be adjacent in the time domain. SUMMARY

[0004] Systems and methods are disclosed for phase compensation for partially overlapped reference signal frequency hopping and related measurement and reporting. In one embodiment, a method performed by a first node of a wireless communication system comprises performing measurements of a target narrowband reference signal from a second node of the wireless communication system, in accordance with a predefined or configured frequency hopping pattern.The method further comprises computing an accumulated wideband reference signal measurement based on the measurements of the target narrowband reference signal in a plurality of frequency hops of the predefined or configured frequency hopping pattern, wherein computing the accumulated wideband reference signal measurement comprises, for a pair of frequency hops from among the plurality of frequency hops that are adjacent in frequency, applying a phase rotation to the measurement(s) performed for one of the pair of frequency hops.

[0005] In one embodiment, the pair of frequency hops comprises an ^^th frequency hop and an ^^th frequency hop that is adjacent to the ^^th frequency hop in frequency domain, and applying the phase rotation comprises applying the phase rotation to the measurement(s) performed for the ^^ th frequency hop. In one embodiment, the phase rotation applied to the measurement(s)performed for the ^^th frequency hop is determined by: Δ^^^ ^ ^^^∗൫థ^,ೖିథ^,ೖ൯^ where Δ^^^^,^ is the phase^^^ is a resource element setof the ^^th frequency hop, ^^^is a resource element set of the ^^th frequency hop, ^^^⋂^^^is a resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and angle(.) is the phase operation.

[0006] In one embodiment, the phase rotation applied to the measurement(s) performed for the ^^th frequency hop is determined by: Δ^^^ ^ ^^ ^∗൫థ^,ೖିథ^,ೖ൯^ where Δ^^^^,^is the phase resource element sethop, ^^ is a resource element set of the ^^th frequency hop, ^^ ^^ is a^ ^⋂^resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, angle(.) is the phase operation, and ^^^,^,^is a weight of resource ^^ of the pair of frequency hops ^^ and ^^. In one embodiment, ^^^,^,^is a product of an amplitude of the target narrowband reference signal (as measured by the first node) in resource ^^ for the ^^th frequency hop and an amplitude of the target narrowband reference signal (asmeasured by the first node) in resource ^^ for the ^^th frequency hop.

[0007] In one embodiment, the phase rotation applied to the measurement(s) performed for the ^^th frequency hop is determined by: Δ^^^^,^ ൌ1 ^mod൫^^^,^ െ ^^^,^ , 2^^൯^ ^where Δ^^^^,^ is thea resource element sethop, ^^ is a resource element set of the ^^th frequency hop, ^^ ^^ is a^ ^ ⋂ ^resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and mod(.) is the modulo operation.

[0008] In one embodiment, computing the accumulated wideband reference signal measurement further comprises, for each additional pair of frequency hops from among the plurality of frequency hops that are adjacent in frequency, applying a phase rotation to the measurement(s) performed for one of the frequency hops in the additional pair of frequency hops.

[0009] In one embodiment, the method further comprises determining a time-based measurement (e.g., ToA, timing advance, or Rx-Tx time difference), based on the accumulated wideband reference signal measurement.

[0010] In one embodiment, the method further comprises determining a UE positioning information (e.g., an estimate of a corresponding UE’s position), based on the accumulated wideband reference signal measurement.

[0011] In one embodiment, the method further comprises using the accumulated wideband reference signal measurement and / or a time-based measurement determined based on the accumulated wideband reference signal measurement for one or more operational tasks (e.g., RSTD calculation, UE position estimation, timing advance estimation).

[0012] In one embodiment, the method further comprises reporting the accumulated wideband reference signal measurement and / or information derived from the accumulated wideband reference signal measurement to another node (e.g., a network node).

[0013] In one embodiment, the first node is a network node, and the second node is a User Equipment (UE). In one embodiment, the target narrowband reference signal is downlink positioning reference signal (PRS).

[0014] In one embodiment, the first node is a UE, and the second node is a network node. In one embodiment, the target narrowband reference signal is uplink sounding reference signal (SRS).

[0015] In one embodiment, the first node is a first network node, and the second node is a second network node.

[0016] In one embodiment, the first node is a first UE, and the second node (404) is a second UE.

[0017] Corresponding embodiments of the first node, the second node, a UE, and a network node are also disclosed herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure.

[0019] Figure 1 illustrates an example of phase compensation for overlapping frequency hops;

[0020] Figures 2 and 3 illustrate two cases (Case 1 and Case 2, respectively) that are examples for frequency hopping transmission and frequency hopping reception;

[0021] Figure 4 illustrates a system 400 including a first node 402 and a second node 404, in which embodiments of the present disclosure may be implemented;

[0022] Figure 5 illustrates the operation of the first node 402 (i.e., receiver) and the second node 404 (i.e., transmitter) in accordance with one example embodiment of the present disclosure;

[0023] Figure 6 shows an example of a communication system in accordance with some embodiments of the present disclosure;

[0024] Figure 7 shows a User Equipment device (UE) in accordance with some embodiments of the present disclosure;

[0025] Figure 8 shows a network node in accordance with some embodiments of the present disclosure;

[0026] Figure 9 shows existence of phase rotation between adjacent frequency hops in the overlapped frequency of those two adjacent hops;

[0027] Figure 10 shows horizontal positioning accuracy in indoor factory, sparse clutter, high gNBs;

[0028] Figure 11 shows RTT-based results comparison of full band and frequency hopping over narrowband, abstracted from Figure 10. DETAILED DESCRIPTION

[0029] The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Uponreading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure.

[0030] 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.

[0031] There currently exist certain challenge(s). In the context of uplink SRS and downlink PRS frequency hopping for RedCap UE positioning, there are several factors that contribute to phase errors between two adjacent frequency hops. These factors include a Phase Locked Loop (PLL) retuning phase error, a phase error caused by timing error, and a phase error caused by UE Tx gain change. In regard to the PLL retuning phase error, there may be random phase rotation due to Radio Frequency (RF) retuning of the center frequency from one hop to another hop. So, the solution is to calculate the phase rotation via comparing the overlapped resources of the phase of these two hops.

[0032] However, as shown in the example below for the calculation of the phase rotation of one pair of hops, there may be potential phase ambiguity.

[0033] Assume an uplink (UL) SRS hopping pattern with ^^ hops. Let ^^^and ^^^be the sets of resource elements of transmission ^^ and transmission ^^ respectively, and ^^^,^ ∈ ^0, 2^^^ bethe measured phase at transmission ^^ and resource element ^^ ∈ ^^^, where ^^,^^ ∈ 1, … ^^. Thephase rotation between the hops can be estimated as: Δ^^^1 ^,^ ൌ ^ ^^^,^ െ ^^^,^^where ^^^ ⋂^^^is the | is their cardinality. Tomitigate the phase rotation, the receiver can align the transmissions by subtracting Δ^^^^,^from all measurements ^^^,^,^^ ∈ 1, … , ^^, ^^ ∈ ^^^. An example is illustrated in Figure 1.

[0034] there may be ambiguity if the distribution of ^^^,^ െ ^^^,^ is close to 0 or 2^^due to the phase noise and the phase change over frequency. For example, if the value of ^^^,^െ ^^^,^ ൌ ^^ and ^^^,ଶ െ ^^^,ଶ ൌ 4^^ , then ^^^^,^ െ ^^^,^ ^ ^^^,ଶ െ ^^^,ଶ^ / 2 ൌ 2.5^^ , instead of the

[0035] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. Embodiments of systems and methods are disclosed herein for solving the ambiguity for the derivation of phase rotation of each pair of adjacent hops in frequency domainfor partially overlapped frequency hopping in order to get the measurement based on the accumulated wide bandwidth, for example, for positioning and / or timing advance purpose.

[0036] Figures 2 and 3 illustrate two cases (Case 1 and Case 2) that are examples for frequency hopping transmission and frequency hopping reception. The frequency hopping patterns applied for the receiver in both cases are with 5 hops which can be aggregated into a wide band reference signal, corresponding to the full bandwidth shown on the right of the figures. Between each pair of adjacent hops, there is an overlapping part in frequency dimension. Difference is that the transmitter in Figure 3 (i.e., Case 2) transmits downlink reference signal by occupying the full scheduled bandwidth which does not apply a narrow band frequency hopping pattern. At the receiver side, especially when it is a RedCap UE, to receive the reference signal with a frequency hopping pattern is still feasible for the communication. Other mechanisms supporting similar features are also possible, and the hops may be stair or no-stair. In a stair pattern, it could also be a wrapped stair. Note that when a frequency hopping pattern is applied, intra or inter slot hopping may also applies at the same time.

[0037] Figure 4 illustrates a system 400 including a first node 402 and a second node 404, in which embodiments of the present disclosure may be implemented. In one example embodiment, the first node 402 is a radio access node (e.g., a base station) of a cellular communications network (e.g., a NR Radio Access Network (RAN), the second node 404 is a UE (e.g., a RedCap UE), and embodiments of the present disclosure are applied with respect to transmission of UL SRS from the UE to the radio access node using an UL SRS frequency hopping transmission scheme. In another example embodiment, the first node 402 is a UE (e.g., a RedCap UE), the second node 404 is a radio access node (e.g., a base station) of a cellular communications network (e.g., a NR RAN), and embodiments of the present disclosure are applied with respect to DL PRS reception at the UE using a DL SRS frequency hopping reception scheme.

[0038] Figure 5 illustrates the operation of the first node 402 (i.e., receiver) and the second node 404 (i.e., transmitter) in accordance with one example embodiment of the present disclosure. As illustrated, the first node 402 performs multiple measurements of a target narrowband reference signal (e.g., UL SRS or DL PRS) transmitted from the second node 404, in accordance with a predefined or configured frequency hopping pattern (step 500). The frequency hopping pattern defines the hops such that hops may overlap in the frequency domain. A phase rotation between two hops can be estimated if the hops have overlapping frequency resources, allowing the receiver to compensate for phase incoherence. Figure 9 shows an example of phase rotation existence by a simulation between two adjacent hops. Measured phases (arg(c,k)) of two adjacent hops are presented by respective types of sample points. The phase differences of the samples atoverlapping frequencies (i.e., subcarriers) indicate that a phase rotation has occurred between the two adjacent hops, since if there were no phase rotation, the measured phases of the samples would be averagely the same at the overlapping subcarriers.

[0039] For any two hops, for example hop ^^ and hop ^^ that are adjacent in frequency domain, ^^^is a resource element set of the hop ^^, ^^^is a resource element set of hop ^^, ^^^ ⋂^^^is a resource element set of overlapped resources in frequency domain of hops ^^ and ^^, ^^^,^is a phase of the measurement performed on the resource element ^^ of the hop ^^, and ^^^,^is a phase of the measurement on resource element ^^ of hop ^^.

[0040] The first node 402 derives an accumulated wideband reference signal measurement from the measurements of the target narrowband reference signal transmitted from the second node 404 (i.e., transmitter) over the multiple frequency hops (step 502). The derivation, or computation, of the accumulated wideband reference signal measurement includes, for each pair of adjacent hops ^^ and ^^ in the frequency domain, rotating a phase of the second hop (i.e., hop ^^^ (step 502A). This phase rotation can be done via at least one of the solutions described below. Note that the derivation of the phase rotation is performed on measurements (i.e., samples) of the signal received in the second hop on resources that overlap resources of the second hop in frequency domain (i.e., measurements or samples of the signal received in the second hop on resources in the resource set defined by ^^^ ⋂^^^), and the phase compensation is implemented on the second hop according to the derived phase rotation for phase coherence of the first hop and the second hop.

[0041] Optionally, the first node 402 may further measure a time of arrival (ToA) of the reference signal based on the accumulated wideband reference signal (step 504). The first node 402 may use the measurement results for the purpose of, for example, reference signal time difference (RSTD) calculation, UE positioning derivation, timing advance derivation (step 506). The first node 402 may report the measurement results and / or further calculated / derived results to the transmitter, the network, and / or other unit (step 508). Note that the second node 404 (i.e., the transmitter) may or may not be one node of the network, and the first node 402 (i.e., the receiver) may or may not be one node of the network.

[0042] Solution 1: The phase rotation of the second hop (i.e., hop ^^) of one pair of hops compared to the first hop (i.e., hop ^^) of this pair of hops is the angle of the sum of imaginary exponential of phase differences of overlapped resources in frequency domain of the first hop and the second hop in the pair of hops, as shown in the example below: Δ^^^ ^∗൫థ ିథ ൯^,^ ൌ ^ ^^ ^,ೖ ^,ೖ^where Δ^^^^,^ is the derived phase rotation which should be applied for the second hop (i.e. hopto the first hop (i.e. hop #m) in the pair of hops (i.e. hop #m and hop #n), ^^^is theresource element set of the first hop (i.e. hop #m), ^^^is the resource element set of the second hop (i.e. hop #n), ^^^ ⋂^^^means the resource element set of the overlapped resources in frequency domain of the first hop (i.e. hop #m) and the second hop (i.e. hop #n), ^^^,^is the phase of the resource element ^^ of the first hop, and ^^^,^is the phase of the resource element ^^ of the second hop, angle(.) means the phase operation, ^^^∗൫థ^,ೖିథ^,ೖ൯means imaginary exponential of ^^^,^െ ^^^,^.

[0043] Solution 2: The phase rotation of the second hop (i.e., hop ^^) of one pair of hops compared to the first hop (i.e., hop ^^) of this pair of hops is the angle of weighted sum of imaginary exponential of phase differences of overlapped resources in frequency domain of the first hop and the second hop in pair of hops, as shown in the example below: ^ ^ where ^^^,^,^is the hop #n. For example, if^^^,^^^^∗థ^,ೖand ^^^,^^^^∗థ^,ೖare the detected signal of resource element k of hop #m and the detected signal of resource element k of hop #n respectively, then ^^^,^,^ ൌ ^^^,^ ∗ ^^^,^.

[0044] Solution 3: The phase rotation of the second hop (i.e., hop ^^) of one pair of hops compared to the first hop (i.e., hop ^^) of this pair of hops is the average of phase differences with limited value range of overlapped resources in frequency domain of the second hop and the first hop in the pair of hops, where the value range of each phase difference is limited within one value range via modulo operation, as shown in the example below Δ^^^^,^ ൌ1 |^^ ^ mod൫^^^,^ െ ^^^,^ , 2^^൯^ ^where mod(.) means the modulo

[0045] Note that, in the example of Figure 2 and Figure 3 with the frequency hopping pattern, hop #1 has no phase rotation in the pair of hop#1 and hop#2. And hop #2 needs to consider the phase rotation compared to hop #1 in the pair of hop#1 and hop#2. And hop #3 needs to consider the phase rotation compared to hop #2 in the pair of hop#2 and hop#3 and the phase rotation of hop #2 in the pair of hop#1 and hop#2. Similarly, hop #4 needs to consider the phase rotation compared to hop#3 in the pair of hop#3 and hop#4, the phase rotation of hop #3 in the pair of hop#2 and hop#3 and the phase rotation of hop#2 in the pair of hop #1 and hop #2. Finally, all rotations have been calculated and then compensated. Another example for one frequency hoppingpattern is that hop #1 has no phase rotation, hop #2 needs to compensate the phase rotation compared to hop #1, hop #3 needs to calculate and compensate the phase rotation compared to hop #2 which has been compensated its phase rotation compared to hop #1. Similarly, hop #4 needs to calculate and compensate the phase rotation compared to hop #3 which has been compensated its phase rotation compared to hop #2, and so on.

[0046] Certain embodiments may provide one or more of the following technical advantage(s). Embodiments of the present disclosure can solve the ambiguity issue during the derivation of phase rotation where the derived phase rotation is used for phase compensation in order to get the measurement based on the accumulated wide bandwidth, for example, for positioning purpose.

[0047] Now, a more detailed description of some example embodiments of the present disclosure will now be described. Note that the wording below of “uplink reference signal” can be replaced by “downlink reference signal”. Note that the wording below of “transmission” can be replaced by the wording of “reception”.

[0048] Embodiment#1

[0049] A UE (operating as the second node 404) is configured with a set of uplink reference signal transmissions by the network (e.g., by the first node 402). The received bandwidth of each uplink transmission is limited to no more than the maximal narrow bandwidth supported by the UE for uplink transmission, but the center frequency of the UE for the uplink transmission from one hop to its adjacent hop in time domain is changed according to a predefined hopping pattern. The network node (operating as the first node 402) can stitch together the UL reference signal transmissions to have a wider bandwidth.

[0050] The aggregated transmissions should be phase coherent to achieve maximal accuracy gains, but a random phase rotation can appear when the UE changes the center frequency and reconfigures and retunes its PLL. Random phase rotation between two hops can however be estimated if the transmissions of these two hops have overlapped frequency resources, allowing the receiver to compensate for them to achieve coherency. Assume an uplink-reference-signalhopping pattern with ^^ hops. Let ^^^ and ^^^ be the sets of subcarriers of transmission ^^ andtransmission ^^ respectively, ^^^,^ ∈ ^0, 2^^^ be the measured phase at transmission ^^ andsubcarrier ^^ ∈ ^^^, ^^^,^ ∈ ^0, 2^^^ be the measured phase at transmission ^^ and subcarrier ^^ ∈ ^^^,where ^^, ^^ ∈ 1, … ^^. The phase rotation between the hops can be estimated from^ 1 Δ^^^,^ ൌ ^ mod൫^^^,^ െ ^^^,^ , 2^^൯^ ^

[0051] The network node may further derive, for example, time-based measurement (e.g., ToA, timing advance, Rx-Tx time difference) and / or UE positioning information based on at least the accumulated UL reference signal with wider bandwidth. The network node may send the derived results to the location server for UE positioning. The network node may send the derived results to the UE for the update of timing advance.

[0052] Embodiment#2

[0053] A UE (operating as the first node 402) is configured with a set of downlink reference signal transmissions from the network node (e.g., the second node 404). The received bandwidth of each downlink reception is limited to no more than the maximal narrow bandwidth supported by the UE for downlink reception, while the center frequency of the UE for the downlink reception from one hop to its adjacent hop in time domain is changed according to for example a predefined hopping pattern. The UE can stitch together the downlink reference signal receptions to have a wider bandwidth.

[0054] The aggregated receptions should be phase coherent to achieve maximal accuracy gains, but a random phase rotation can appear when the UE changes the center frequency and reconfigures and retunes its PLL. Random phase rotation between two hops can however be estimated if the receptions of these two hops have overlapped frequency resources, allowing the receiver to compensate for them to achieve coherency. Assume a downlink-reference-signal hopping pattern with ^^ hops. Let ^^^and ^^^be the sets of subcarriers of reception ^^ and reception^^ respectively, ^^^,^ ∈ ^0, 2^^^ be the measured phase at reception ^^ and subcarrier ^^ ∈ ^^^ ,^^^,^ ∈ ^0, 2^^^ be the measured phase at reception ^^ and subcarrier ^^ ∈ ^^^, where ^^,^^ ∈ 1, … ^^.The phase rotation between the hops can be estimated from 1 Δ^^^^,^ ൌ^^^ mod൫^^^,^ െ ^^^,^ , 2^^൯^ ^

[0055] The UE (e.g., ToA, timingadvance, Rx-Tx time difference, RSTD) and / or UE positioning information based on at least the accumulated DL reference signal with wider bandwidth. The UE may send the derived results to the location server for UE positioning. The UE may send the derived results to the network for UE positioning and / or the update of timing advance.

[0056] Embodiment#3

[0057] Similar to Embodiment#1 for a network node, the phase rotation between hop m and hop n can be estimated byΔ^^^ ^ ^^^∗൫థ^,ೖିథ^,ೖ൯^

[0058] In one pair of hops compared tothe first hop of the pair of hops is done via multiplying the detected signals of the overlapped resources of the second hop compared to the first hop by the phase rotation factor below ^^^ ൌ a^,^^^^where ^^^is the complex vector of the signal detected by the second node (e.g., hop#m) and a^,^is the phase rotation factor of hop pair (n,m). a^,^can be derived by ∑^∗^∈ ^^ ൫థ^,ೖିథ^,ೖ൯a ൌ^^ ⋂^^^,^and the value of a^,^is

[0059] Embodiment#4

[0060] Similar to Embodiment#3 a the network node, the phase rotation between hop m and hop n can be estimated by ^

[0061] In one pair of hops compared tothe first hop of the pair of hops is done via multiplying the detected signals of the overlapped resources of the second hop compared to the first hop by the phase rotation factor below ^^^ ൌ a^,^^^^where ^^^is the complex vector of the signal detected by the second node (e.g., hop#m) and a^,^is the phase rotation factor of hop pair (n,m). a^,^can be derived by ^^ᇱ^^ a ൌ^|^^⋂^^ ^|^^⋂^^^,^where ^^^|^^⋂^^is complex second node (e.g. hop#m) in theoverlapped resources of hop#m and hop#n (i.e. ^^^ ⋂^^^), and ^. ^ᇱis the conjugate transpose operator. Note that the value of a^,^is equal to ^^^∗^థ^^,^.

[0062] Embodiment#5

[0063] Similar to Embodiment#2 for a user equipment, the phase rotation between hop m and hop n can be estimated by Δ^^^ ^∗൫థ ିథ ൯^,^ ൌ ^ ^^ ^,ೖ ^,ೖ^

[0064] Embodiment#6

[0065] Similar to Embodiment#2 for a user equipment, the phase rotation between hop m and hop n) can be estimated by ^

[0066] Extension

[0067] The UE in Embodiment#1, 2, 3, 4, 5, or 6 may be replaced by a network node, and / or the network in Embodiment#1, 2, 3, 4, 5, or 6 may be replaced by another UE.Figure 6 shows an example of a communication system 600 in which the embodiments described below may be implemented, in accordance with some embodiments.

[0068] In the example, the communication system 600 includes a telecommunication network 602 that includes an access network 604, such as a Radio Access Network (RAN), and a core network 606, which includes one or more core network nodes 608. The access network 604 includes one or more access network nodes, such as network nodes 610A and 610B (one or more of which may be generally referred to as network nodes 610), or any other similar Third Generation Partnership Project (3GPP) access nodes or non-3GPP Access Points (APs). 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 602 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 602 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 602, including one or more network nodes 610 and / or core network nodes 608.

[0069] 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 openfronthaul 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 O-2 interface defined by the O-RAN Alliance or comparable technologies. The network nodes 610 facilitate direct or indirect connection of User Equipment (UE), such as by connecting UEs 612A, 612B, 612C, and 612D (one or more of which may be generally referred to as UEs 612) to the core network 606 over one or more wireless connections.

[0070] Note that, in some embodiments, the first node 402 described above is one of the network nodes 610, and the second node 404 described above is one of the UEs 612. In some other embodiments, the first node 402 described above is one of the UEs 612, and the second node 404 described above is one of the network nodes 610. In some other embodiments, the first node 402 described above is one of the UEs 612, and the second node 404 described above is another one of the UEs 612. In some other embodiments, the first node 402 described above is one of the network nodes 610, and the second node 404 described above is another one of the network nodes 610.

[0071] 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 600 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 600 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0072] The UEs 612 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 610 and other communication devices. Similarly, the network nodes 610 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 612 and / or with other network nodes or equipment in the telecommunication network 602 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 602.

[0073] In the depicted example, the core network 606 connects the network nodes 610 to one or more hosts, such as host 616. 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 606 includes one more core network nodes (e.g., core network node 608) 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 608. 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 (AUSF), Subscription Identifier De-Concealing Function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and / or a User Plane Function (UPF).

[0074] The host 616 may be under the ownership or control of a service provider other than an operator or provider of the access network 604 and / or the telecommunication network 602, and may be operated by the service provider or on behalf of the service provider. The host 616 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.

[0075] As a whole, the communication system 600 of Figure 6 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system 600 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 Second, Third, Fourth, or Fifth Generation (2G, 3G, 4G, or 5G) standards, or any applicable future generation standard (e.g., Sixth Generation (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.

[0076] In some examples, the telecommunication network 602 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunication network 602 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 602. For example, the telecommunication network 602 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 Internet of Things (IoT) services to yet further UEs.

[0077] In some examples, the UEs 612 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 604 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 604. Additionally, a UE may be configured for operating in single- or multi-Radio Access Technology (RAT) or multi-standard mode. For example, a UE may operate with any one or combination of WiFi, New Radio (NR), and LTE, i.e. being configured for Multi-Radio Dual Connectivity (MR-DC), such as Evolved UMTS Terrestrial RAN (E-UTRAN) NR - Dual Connectivity (EN-DC).

[0078] In the example, a hub 614 communicates with the access network 604 to facilitate indirect communication between one or more UEs (e.g., UE 612C and / or 612D) and network nodes (e.g., network node 610B). In some examples, the hub 614 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 614 may be a broadband router enabling access to the core network 606 for the UEs. As another example, the hub 614 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 610, or by executable code, script, process, or other instructions in the hub 614. As another example, the hub 614 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 614 may be a content source. For example, for a UE that is a Virtual Reality (VR) headset, display, loudspeaker or other media delivery device, the hub 614 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 614 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 614 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy IoT devices.

[0079] The hub 614 may have a constant / persistent or intermittent connection to the network node 610B. The hub 614 may also allow for a different communication scheme and / or schedule between the hub 614 and UEs (e.g., UE 612C and / or 612D), and between the hub 614 and the core network 606. In other examples, the hub 614 is connected to the core network 606 and / or one or more UEs via a wired connection. Moreover, the hub 614 may be configured to connect to a Machine-to-Machine (M2M) service provider over the access network 604 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 610 while still connected via the hub 614 via a wired or wireless connection. In some embodiments, the hub 614 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 610B. In other embodiments, the hub 614 may be a non-dedicated hub – that is, a device which is capable of operating to route communications between the UEs and the network node 610B, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0080] Figure 7 shows a UE 700 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 Internet Protocol (VoIP) phone, wireless local loop phone, desktop computer, Personal Digital Assistant (PDA), wireless camera, 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 3GPP, including a Narrowband Internet of Things (NB-IoT) UE, a Machine Type Communication (MTC) UE, and / or an enhanced MTC (eMTC) UE.

[0081] 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 enduser but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

[0082] The UE 700 includes processing circuitry 702 that is operatively coupled via a bus 704 to an input / output interface 706, a power source 708, memory 710, a communication interface 712, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 7. 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.

[0083] The processing circuitry 702 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 710. The processing circuitry 702 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 702 may include multiple Central Processing Units (CPUs).

[0084] In the example, the input / output interface 706 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 700. 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.

[0085] In some embodiments, the power source 708 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 708 may further include power circuitry for delivering power from the power source 708 itself, and / or an external power source,to the various parts of the UE 700 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 708. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 708 to make the power suitable for the respective components of the UE 700 to which power is supplied.

[0086] The memory 710 may be or be configured to include memory such as Random Access Memory (RAM), Read Only Memory (ROM), Programmable ROM (PROM), Erasable PROM (EPROM), Electrically EPROM (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 710 includes one or more application programs 714, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 716. The memory 710 may store, for use by the UE 700, any of a variety of various operating systems or combinations of operating systems.

[0087] The memory 710 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 RAM (SDRAM), external micro-DIMM SDRAM, smartcard memory such as a tamper resistant module in the form of a Universal Integrated Circuit Card (UICC) including one or more Subscriber Identity Modules (SIMs), such as a Universal SIM (USIM) and / or Internet Protocol Multimedia Services Identity Module (ISIM), other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as a ‘SIM card.’ The memory 710 may allow the UE 700 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 710, which may be or comprise a device-readable storage medium.

[0088] The processing circuitry 702 may be configured to communicate with an access network or other network using the communication interface 712. The communication interface 712 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 722. The communication interface 712 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 718 and / or a receiver 720appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 718 and receiver 720 may be coupled to one or more antennas (e.g., the antenna 722) and may share circuit components, software, or firmware, or alternatively be implemented separately.

[0089] In the illustrated embodiment, communication functions of the communication interface 712 may include cellular communication, WiFi communication, LPWAN communication, data communication, voice communication, multimedia communication, short- range communications such as Bluetooth, NFC, 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 according to one or more communication protocols and / or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband CDMA (WCDMA), GSM, LTE, NR, UMTS, WiMax, Ethernet, Transmission Control Protocol / Internet Protocol (TCP / IP), Synchronous Optical Networking (SONET), Asynchronous Transfer Mode (ATM), Quick User Datagram Protocol Internet Connection (QUIC), Hypertext Transfer Protocol (HTTP), and so forth.

[0090] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 712, 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).

[0091] 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.

[0092] A UE, when in the form of an IoT 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 IoT device are a device which is or which is embedded in: a connected refrigerator or freezer, a television, 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 / windowsensor, 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 smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or 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 IoT device comprises circuitry and / or software in dependence of the intended application of the IoT device in addition to other components as described in relation to the UE 700 shown in Figure 7.

[0093] As yet another specific example, in an IoT 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-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship, an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation.

[0094] 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.

[0095] Figure 8 shows a network node 800 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, APs (e.g., radio APs), Base Stations (BSs) (e.g., radio BSs, Node Bs, evolved Node Bs (eNBs), NR Node Bs (gNBs)), and O-RAN nodes or components of an O-RAN node (e.g., O-RU, O-DU, O-CU).

[0096] 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 ofcoverage, 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 RRUs 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).

[0097] 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 BS Controllers (BSCs), Base Transceiver Stations (BTSs), transmission points, transmission nodes, Multi-Cell / 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).

[0098] The network node 800 includes processing circuitry 802, memory 804, a communication interface 806, and a power source 808. The network node 800 may be composed of multiple physically separate components (e.g., a NodeB component and an 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 800 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 800 may be configured to support multiple RATs. In such embodiments, some components may be duplicated (e.g., separate memory 804 for different RATs) and some components may be reused (e.g., a same antenna 810 may be shared by different RATs). The network node 800 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 800, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, Long Range Wide Area Network (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 the network node 800.

[0099] The processing circuitry 802 may comprise a combination of one or more of a microprocessor, controller, microcontroller, CPU, DSP, ASIC, FPGA, or any other suitable computing device, resource, or combination of hardware, software, and / or encoded logic operableto provide, either alone or in conjunction with other network node 800 components, such as the memory 804, to provide network node 800 functionality.

[0100] In some embodiments, the processing circuitry 802 includes a System on a Chip (SOC). In some embodiments, the processing circuitry 802 includes one or more of Radio Frequency (RF) transceiver circuitry 812 and baseband processing circuitry 814. In some embodiments, the RF transceiver circuitry 812 and the baseband processing circuitry 814 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 the RF transceiver circuitry 812 and the baseband processing circuitry 814 may be on the same chip or set of chips, boards, or units.

[0101] The memory 804 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, RAM, 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 802. The memory 804 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 802 and utilized by the network node 800. The memory 804 may be used to store any calculations made by the processing circuitry 802 and / or any data received via the communication interface 806. In some embodiments, the processing circuitry 802 and the memory 804 are integrated.

[0102] The communication interface 806 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 806 comprises port(s) / terminal(s) 816 to send and receive data, for example to and from a network over a wired connection. The communication interface 806 also includes radio front-end circuitry 818 that may be coupled to, or in certain embodiments a part of, the antenna 810. The radio front-end circuitry 818 comprises filters 820 and amplifiers 822. The radio front-end circuitry 818 may be connected to the antenna 810 and the processing circuitry 802. The radio front-end circuitry 818 may be configured to condition signals communicated between the antenna 810 and the processing circuitry 802. The radio front-end circuitry 818 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 818 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of the filters 820 and / or theamplifiers 822. The radio signal may then be transmitted via the antenna 810. Similarly, when receiving data, the antenna 810 may collect radio signals which are then converted into digital data by the radio front-end circuitry 818. The digital data may be passed to the processing circuitry 802. In other embodiments, the communication interface 806 may comprise different components and / or different combinations of components.

[0103] In certain alternative embodiments, the network node 800 does not include separate radio front-end circuitry 818; instead, the processing circuitry 802 includes radio front-end circuitry and is connected to the antenna 810. Similarly, in some embodiments, all or some of the RF transceiver circuitry 812 is part of the communication interface 806. In still other embodiments, the communication interface 806 includes the one or more ports or terminals 816, the radio front-end circuitry 818, and the RF transceiver circuitry 812 as part of a radio unit (not shown), and the communication interface 806 communicates with the baseband processing circuitry 814, which is part of a digital unit (not shown).

[0104] The antenna 810 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 810 may be coupled to the radio front-end circuitry 818 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 810 is separate from the network node 800 and connectable to the network node 800 through an interface or port.

[0105] The antenna 810, the communication interface 806, and / or the processing circuitry 802 may be configured to perform any receiving operations and / or certain obtaining operations described herein as being performed by the network node 800. Any information, data, and / or signals may be received from a UE, another network node, and / or any other network equipment. Similarly, the antenna 810, the communication interface 806, and / or the processing circuitry 802 may be configured to perform any transmitting operations described herein as being performed by the network node 800. Any information, data, and / or signals may be transmitted to a UE, another network node, and / or any other network equipment.

[0106] The power source 808 provides power to the various components of the network node 800 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 808 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 800 with power for performing the functionality described herein. For example, the network node 800 may be connectable to an external power source (e.g., the power grid or an electricity outlet) via input circuitry or an interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 808. As a further example, the power source 808may 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.

[0107] Embodiments of the network node 800 may include additional components beyond those shown in Figure 8 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 800 may include user interface equipment to allow input of information into the network node 800 and to allow output of information from the network node 800. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 800.

[0108] Horizontal positioning accuracy results can be seen in Figure 10. In general, the RTT- based results outperform the TDOA-based results. RTT means round trip time (RTT) positioning solution which needs to UE-side DL PRS based measurement and network-side UL SRS based measurement. UL TDOA-based curves are omitted from this figure since they are very similar to the DL TDOA-based curves. The 20 MHz results are slightly higher than 1m@90% for RTT and far above this number for TDOA. And the frequency hopping strategy enables 2dm@90% for TDOA and 7cm@90% for RTT. In order to look clearer at accuracy results regarding frequency hopping, DL-TDOA curves are omitted in Figure 11, where readers can focus on RTT-based results. It can be seen that the CDF (cumulative distribution function) curve of 100MHz bandwidth of DL PRS (or UL SRS) almost overlaps with that of a 6 hops’ bandwidth of each hop being 20MHz.

[0109] The overlap means the solution of frequency hopping over narrowband for narrowband UEs can achieve same performance as the solution with full bandwidth for normal UE. Frequency hopping can significantly enhance positioning performance of hardware limited devices, such as RedCap devices, restricted to 20 MHz bandwidth, enabling sub-meter positioning accuracies. The results in Figure 11 demonstrates that it is of great help for lightweight suboptimal TOA detectors in multipath situations. The interpolating TOA detector outlined in this section is optimal (in maximum likelihood sense) for the single-path situation, and close to optimal if the TOA channel artifact is isolated from other reflections in the channel, so that the multipath smearing effects are negligible. However, in the indoor factory channel model, and often in practice, near-in multipath smearing is significant.

[0110] 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 understoodthat 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.

[0111] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored 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 hardwired 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.

[0112] Those skilled in the art will recognize improvements and modifications to the embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein.EMBODIMENTS 1. A method performed by a first node (402) of a wireless communication system (400), the method comprising: performing (500) measurements of a target narrowband reference signal from a second node (404) of the wireless communication system (400), in accordance with a predefined or configured frequency hopping pattern; computing (502) an accumulated wideband reference signal measurement based on the measurements of the target narrowband reference signal in a plurality of frequency hops of the predefined or configured frequency hopping pattern; wherein computing (502) the accumulated wideband reference signal measurement comprises, for a pair of frequency hops from among the plurality of frequency hops that are adjacent in frequency: applying (502A) a phase rotation to the measurement(s) performed for one of the pair of frequency hops. 2. The method of embodiment 1, wherein the pair of frequency hops comprises an ^^th frequency hop and an ^^th frequency hop that is adjacent to the ^^th frequency hop in frequency domain, applying (502A) the phase rotation comprises applying (502A) the phase rotation to the measurement(s) performed for the ^^th frequency hop. 3. The method of embodiment 2, wherein the phase rotation applied to the measurement(s) performed for the ^^th frequency hop is determined by: ^^^^∗൫థ^,ೖିథ^,ೖ൯^ where Δ^^^^,^is the phase ^^ is a resource element set^hop, ^^^is a resource element set of the ^^th frequency hop, ^^ ⋂^^ is a^ ^resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and angle(.) is the phase operation. 4. The method of embodiment 2, wherein the phase rotation applied to the measurement(s) performed for the ^^th frequency hop is determined by:Δ^^^ ^∗൫థ^,^ ൌ ^ ^^ ^,ೖିథ^,ೖ൯^ where Δ^^^^,^is the phase rotation applied resource element setof the ^^th frequency hop, ^^^is a resource element set of the ^^th frequency hop, ^^^⋂^^^is a resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, angle(.) is the phase operation, and ^^^,^,^is a weight of resource ^^ of the pair of frequency hops ^^ and ^^. 5. The method of embodiment 4, wherein ^^^,^,^is a product of an amplitude of the target narrowband reference signal (as measured by the first node) in resource ^^ for the ^^th frequency hop and an amplitude of the target narrowband reference signal (as measured by the first node) in resource ^^ for the ^^th frequency hop. 6. The method of embodiment 2, wherein the phase rotation applied to the measurement(s) performed for the ^^th frequency hop is determined by: ^ 1 Δ^^^,^ ൌ ^ mod൫^^^,^ െ ^^^,^ , 2^^൯where Δ^^^^,^is the a resource element sethop, ^^ is a resource element set of the ^^th frequency hop, ^^ ^^ is a^ ^ ⋂ ^resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and mod(.) is the modulo operation. 7. The method of any of embodiments 1 to 6, wherein computing (502) the accumulated wideband reference signal measurement further comprises, for each additional pair of frequency hops from among the plurality of frequency hops that are adjacent in frequency: applying (502A) a phase rotation to the measurement(s) performed for one of the frequency hops in the additional pair of frequency hops. 8. The method of any of embodiments 1 to 7, further comprising determining (504) a time-based measurement (e.g., ToA, timing advance, or Rx-Tx time difference), based on the accumulated wideband reference signal measurement. 9. The method of any of embodiments 1 to 7, further comprising determining (504) a UE positioning information (e.g., an estimate of a corresponding UE’s position), based on the accumulated wideband reference signal measurement. 10. The method of any of embodiments 1 to 9, further comprising using (506) the accumulated wideband reference signal measurement and / or a time-based measurement determined based on the accumulated wideband reference signal measurement for one or more operational tasks (e.g., RSTD calculation, UE position estimation, timing advance estimation). 11. The method of any of embodiments 1 to 10, further comprising reporting (508) the accumulated wideband reference signal measurement and / or information derived from the accumulated wideband reference signal measurement to another node (e.g., a network node). 12. The method of any of embodiments 1 to 11, wherein the first node (402) is a network node, and the second node (404) is a User Equipment, UE. 13. The method of embodiment 12, wherein the target narrowband reference signal is downlink positioning reference signal, PRS. 14. The method of any of embodiments 1 to 11, wherein the first node (402) is a User Equipment, UE, and the second node (404) is a network node. 15. The method of embodiment 14, wherein the target narrowband reference signal is uplink sounding reference signal, SRS. 16. The method of any of embodiments 1 to 11, wherein the first node (402) is a first network node, and the second node (404) is a second network node. 17. The method of any of embodiments 1 to 11, wherein the first node (402) is a first User Equipment, UE, and the second node (404) is a second UE.Group A Embodiments 18. A method performed by a User Equipment, UE, the method comprising any of the steps of any of embodiments 1 to 11 wherein the UE is the first node. 19. The method of embodiment 18, wherein the target narrowband reference signal is uplink sounding reference signal, SRS. 20. The method of any of the previous embodiments, further comprising: providing user data; and forwarding the user data to a host via the transmission to the network node. Group B Embodiments 21. A method performed by a network node, the method comprising any of the steps of any of embodiments 1 to 11 wherein the network node is the first node: 22. The method of embodiment 21, wherein the target narrowband reference signal is downlink positioning reference signal, PRS. 23. The method of any of the previous embodiments, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment. Group C Embodiments 24. A user equipment comprising: processing circuitry configured to perform any of the steps of any of the Group A embodiments; and power supply circuitry configured to supply power to the processing circuitry. 25. A network node comprising: processing circuitry configured to perform any of the steps of any of the Group B embodiments; and power supply circuitry configured to supply power to the processing circuitry.26. A user equipment (UE) comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Group A embodiments; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE. 27. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a network node in a cellular network for transmission to a user equipment (UE), the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. 28. The host of the previous embodiment, wherein: the processing circuitry of the host is configured to execute a host application that provides the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host. 29. A method implemented in a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the network node performs any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE.30. The method of the previous embodiment, further comprising, at the network node, transmitting the user data provided by the host for the UE. 31. The method of any of the previous 2 embodiments, wherein the user data is provided at the host by executing a host application that interacts with a client application executing on the UE, the client application being associated with the host application. 32. A communication system configured to provide an over-the-top (OTT) service, the communication system comprising: a host comprising: processing circuitry configured to provide user data for a user equipment (UE), the user data being associated with the over-the-top service; and a network interface configured to initiate transmission of the user data toward a cellular network node for transmission to the UE, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. 33. The communication system of the previous embodiment, further comprising: the network node; and / or the UE. 34. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to initiate receipt of user data; and a network interface configured to receive the user data from a network node in a cellular network, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to receive the user data from a user equipment (UE) for the host. 35. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application that receives the user data; and the host application is configured to interact with a client application executing on the UE,the client application being associated with the host application. 36. The host of the any of the previous 2 embodiments, wherein the initiating receipt of the user data comprises requesting the user data. 37. A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, initiating receipt of user data from the UE, the user data originating from a transmission which the network node has received from the UE, wherein the network node performs any of the steps of any of the Group B embodiments to receive the user data from the UE for the host. 38. The method of the previous embodiment, further comprising at the network node, transmitting the received user data to the host. 39. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the operations of any of the Group A embodiments to receive the user data from the host. 40. The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data to the UE from the host. 41. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.42. A method implemented by a host operating in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the UE performs any of the operations of any of the Group A embodiments to receive the user data from the host. 43. The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the host application. 44. The method of the previous embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application. 45. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments to transmit the user data to the host. 46. The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data from the UE to the host. 47. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE,the client application being associated with the host application. 48. A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, receiving user data transmitted to the host via the network node by the UE, wherein the UE performs any of the steps of any of the Group A embodiments to transmit the user data to the host. 49. The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE. 50. The method of the previous 2 embodiments, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.

Claims

CLAIMS 1. A method performed by a first node (402) of a wireless communication system (400), the method comprising: performing (500) measurements of a target narrowband reference signal from a second node (404) of the wireless communication system (400), in accordance with a frequency hopping pattern; computing (502) an accumulated wideband reference signal measurement based on the measurements of the target narrowband reference signal in a plurality of frequency hops of the frequency hopping pattern; wherein computing (502) the accumulated wideband reference signal measurement comprises, for a pair of frequency hops that are adjacent in frequency among the plurality of frequency hops: applying (502A) a phase rotation to the measurement(s) performed for one of the pair of frequency hops.

2. The method of claim 1, wherein the pair of frequency hops comprises an ^^th frequency hop and an ^^th frequency hop that is adjacent to the ^^th frequency hop in frequency domain,applying (502A) the phase rotation comprises applying (502A) phase rotation Δ^^^^,^ to themeasurement(s) performed for the ^^th frequency hop, which is determined by: Δ^^^ ^ ^^^∗൫థ^,ೖିథ^,ೖ൯ ^where^^^is a resource element set of the ^^th frequency hop, ^^^is a resource element set of the ^^th frequency hop, ^^^⋂^^^is a resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and angle(.) is the phase operation.

3. The method of claim 1, wherein the pair of frequency hops comprises an ^^th frequency hop and an ^^th frequency hop that is adjacent to the ^^th frequency hop in frequency domain, applying (502A) the phase rotation comprises applying (502A) phase rotation Δ^^^^,^to themeasurement(s) performed for the ^^th frequency hop, which is determined by: Δ^^^ ൌ ^∗൫థ^,ೖିథ^,ೖ൯^,^ ^^ where^^^is a resource element set of the ^^th frequency hop, ^^^is a resource element set of the ^^th frequency hop, ^^^ ⋂^^^is a resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, angle(.) is the phase operation, and ^^^,^,^is a weight of resource ^^ of the pair of frequency hops ^^ and ^^.

4. The method of Claim 3, wherein ^^^,^,^is a product of an amplitude of the target narrowband reference signal in resource ^^ for the ^^th frequency hop and an amplitude of the target narrowband reference signal in resource ^^ for the ^^th frequency hop.

5. The method of claim 1, wherein the pair of frequency hops comprises an ^^th frequency hop and an ^^th frequency hop that is adjacent to the ^^th frequency hop in frequency domain,applying (502A) the phase rotation comprises applying (502A) phase rotation Δ^^^^,^ to themeasurement(s) performed for the ^^th frequency hop, which is determined by: Δ^^^^,^ ൌ1 ^mod൫^^^,^ െ ^^^,^ , 2^^൯^where^^^is a resource element set of the ^^th frequency hop, ^^^is a resource element set of the ^^th frequency hop, ^^^ ⋂^^^is a resource element set consisting of overlapped resources in frequency domain of the ^^th frequency hop and the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, ^^^,^is a phase of the measurement for resource element ^^ of the ^^th frequency hop, and mod(.) is the modulo operation.

6. The method of any of the preceding claims, wherein computing (502) the accumulatedwideband reference signal measurement further comprises, for each additional pair of frequency hops that are adjacent in frequency among the plurality of frequency hops: applying (502A) a phase rotation to the measurement(s) performed for one of the frequency hops in the additional pair of frequency hops.

7. The method of any of the preceding claims, further comprising: based on the accumulated wideband reference signal measurement, determining (504) at least one of: Time of arrival, ToA, timing advance, TA, or Rx-Tx time difference.

8. The method of claim 7, further comprising: based on the accumulated wideband reference signal measurement and any of ToA, TA or Rx-Tx time difference, determining at least one of: reference signal time difference, RSTD calculation, User Equipment, UE, position estimation, or timing advance derivation.

9. The method of any of the preceding claims, wherein the target narrowband reference signal is downlink positioning reference signal, PRS; wherein the first node (402) is a network node, and the second node (404) is a UE.

10. The method of any of the claims 1 to 8, wherein the target narrowband reference signal is uplink sounding reference signal, SRS; wherein the first node (402) is a UE, and the second node (404) is a network node.

11. The method of any of the claims 1 to 8, wherein the first node and the second node are both UEs or network nodes.

12. A communication node configured for wireless communication, comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Claims 1 to 11; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to outputinformation from the communication node that has been processed by the processing circuitry; and a power supply circuitry connected to the processing circuitry and configured to supply power to the communication node.

13. A communication node, comprising: processing circuitry configured to perform any of the steps of any of Claims 1 to 11; and power supply circuitry configured to supply power to the processing circuitry.

14. The communication node of claim 12 or 13, wherein the communication node is a UE or a network node.

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