Methods for enabling communication of data to and / or from a wireless device, related network nodes and related wireless devices

Abstract

A method is disclosed, performed by a network node, for enabling communication data to and / or from a wireless device. The method comprises communicating, between the network node and the wireless device, a configuration of a phase tracking reference signal, PTRS, embedding data. The configuration enables the wireless device to retrieve data embedded in the PTRS, and / or to transmit the PTRS embedding data.

Description

The present disclosure pertains to the field of wireless communications. The present disclosure relates to a method for enabling communication of data to and / or from a wireless device, related network nodes and related wireless devices.BACKGROUNDIn New Radio (NR) systems, there are many types of reference signals. One type of reference signals is the Phase Tracking Reference Signal (PTRS). The PTRS serves the purpose of allowing a receiver device to track the Common Phase Offset (CPO) between the transmitter device and the receiver device.However, there is room for improvement of the PTRS design for enhancing the capacity of the system.SUMMARYPTRSs are not meant to be used for channel estimation used in the data demodulation stage. For example, Demodulation Reference Signals (DMRS) are relied upon for that. This allows using any format of PTRS as long as the ability to track the CPO is maintained. A resource element dedicated to a reference symbol allows for estimation of one phase value and one amplitude value, but a resource element occupied by a PTRS is only used for its phase estimation capability. In other words, the PTRSs may be regarded as "under-exploited" as PTRSs are not used for estimation of amplitudes. This shows that PTRSs waste to some extent resources by not exploiting the amplitude estimation.Accordingly, there is a need for network nodes, wireless devices, and methods for enabling communication of data to and / or from a wireless device, which may mitigate, alleviate or address the shortcomings existing and embed data (e.g., user data and / or control data) into the PTRS to enhance the overall capacity of the system, with minimal impact on the CPO tracking ability.A method is disclosed, performed by a network node, for enabling communication data to and / or from a wireless device. The method comprises communicating, between the network node and the wireless device, a configuration of a phase tracking reference signal, PTRS, embedding data. The configuration enables the wireless device to retrieve data embedded in the PTRS, and / or to transmit the PTRS embedding data.Further, a network node is provided, the network node comprising memory circuitry, processor circuitry, and a wireless interface, wherein the network node is configured to perform any of the methods disclosed herein and relating to the network node.It is an advantage of the present disclosure that the disclosed method and network node enable exploiting the amplitude part of the PTRS to carry data, such as user data and / or control data. This results in enabling an enhancement of the capacity of the wireless communication system while maintaining the phase tracking. In other words, this disclosure allows an improvement of the throughput performance by embedding data in the PTRS that can be retrieved by a receiver device and / or transmitted by the network node using the disclosed configuration of the PTRS.A method is disclosed, performed by a wireless device, for enabling communication of data to / and or from the wireless device. The method comprises communicating a configuration of a phase tracking reference signal, PTRS embedding data. The configuration enables the wireless device to retrieve the data embedded in the PTRS, and / or to transmit the PTRS embedding data.Further, a wireless device is provided, the wireless device comprising memory circuitry, processor circuitry, and a wireless interface, wherein the network node is configured to perform any of the methods disclosed herein and relating to the network node.It is an advantage of the present disclosure that the disclosed method and wireless device allow the communication of PTRS embedding data, e.g., in uplink, downlink, and / or sidelink. This enables an enhancement of the throughput while maintaining the phase tracking.BRIEF DESCRIPTION OF THE DRAWINGSThe above and other features and advantages of the present disclosure will become readily apparent to those skilled in the art by the following detailed description of examples thereof with reference to the attached drawings, in which:Fig. 1 is a diagram illustrating an example wireless communication system comprising an example network node and example wireless devices according to this disclosure,Figs. 2A-B are diagrams illustrating PTRSs in time and frequency,Figs. 3A-B are signalling diagrams illustrating example embodiments of this disclosure,Fig. 4 shows a signalling diagram of an example embodiment of this disclosure for sidelink,Figs. 5 shows a flow-chart illustrating an example method, performed in a network node of a wireless communication system, for enabling communication of data to and / or from a wireless device according to this disclosure,Fig. 6 is a flow-chart illustrating an example method, performed in a wireless device, for enabling communication of data to and / or from a wireless device according to this disclosure,Fig. 7 is a block diagram illustrating an example network node according to this disclosure,Fig. 8 is a block diagram illustrating an example wireless device according to this disclosure, andFigs. 9A-B shows graphs illustrating example numerical results according to this disclosure.DETAILED DESCRIPTIONVarious examples and details are described hereinafter, with reference to the figures when relevant. It should be noted that the figures may or may not be drawn to scale and that elements of similar structures or functions are represented by like reference numerals throughout the figures. It should also be noted that the figures are only intended to facilitate the description of the examples. They are not intended as an exhaustive description of the disclosure or as a limitation on the scope of the disclosure. In addition, an illustrated example needs not have all the aspects or advantages shown. An aspect or an advantage described in conjunction with a particular example is not necessarily limited to that example and can be practiced in any other examples even if not so illustrated, or if not so explicitly described.The figures are schematic and simplified for clarity, and they merely show details which aid understanding the disclosure, while other details have been left out. Throughout, the same reference numerals are used for identical or corresponding parts.Fig. 1 is a diagram illustrating an example wireless communication system 1 comprising an example network node 400 and an example wireless device 300 according to this disclosure.As discussed in detail herein, the present disclosure relates to a wireless communication system 1 comprising a cellular system, for example, a 3rd Generation Partnership Project (3GPP) wireless communication system, such as an NR system.The wireless communication system 1 comprises a wireless device 300 and / or a network node 400.A network node disclosed herein refers to a radio access network node operating in the radio access network, such as a base station, an evolved Node B, eNB, gNB in NR. In one or more examples, the RAN node is a functional unit which may be distributed in several physical units.In one or more examples, RAN node is a functional unit which may be distributed in several physical units.The wireless communication system 1 described herein may comprise one or more wireless devices 300, 300A, and / or one or more network nodes 400, such as one or more of: a base station, an eNB, a gNB and / or an access point.A wireless device may refer to a mobile device and / or a user equipment, UE.The wireless device 300, 300A is configured to communicate with the network node 400 via a wireless link (or radio access link) 10, 10A. The wireless device 300 may be configured to communicate with a sidelink wireless device, such as wireless device 300A via a wireless link (or radio access link), 11.Figs. 2A-2B are diagrams illustrating PTRS in time and frequency. In Figs. 2A-2B, the time-frequency grids show resource elements for Physical Downlink Control Channel 20 (PDCCH), resource elements for DMRS 22, and resource elements for PTRS 23. Blank resource elements of Figs. 2A-2B are resource elements to carry data, such as user data. For example, the user data can be carried in the Physical Downlink Shared Channel (PDSCH).In Fig. 2A, the PTRS 23, when present, are continuously placed in the time domain with a configurable density. In the frequency domain, they are repeated with much lesser density (not shown in Fig. 2A).It is assumed that the channel along the DMRS 22 occupying resource elements across the frequency domain, is denoted H₀ = [H₀,₁ H₀,₂ ... H₀,N]ᵀ where N is the number of allocated subcarriers. At low Doppler, the channel may be considered as being static throughout the shown time duration in Figs. 2A-2B. However, due to the CPO, the radio channel in the kth symbol (where k = 0 is the symbol in which the DMRS are located) can be described as Hk = exp (iфk)H₀ where фk is the CPO. The radio channel described this way may be seen as the propagation channel and / or the overall channel between the digital parts of the receiver and transmitter, (e.g., including mismatches in, e.g., oscillators at the two ends).A representative model for фk is фk = k∆. In other words, the CPO drifts with rate ∆ radians per symbol.Since the PTRS 23 are scarce along the frequency dimension as illustrated in Figs. 2A-B, an estimation of the channel at subcarriers far from the PTRS 23 can rely only on the DMRS 22. For example, a practical channel estimator first obtains an estimate Ĥ₀ of channel H₀ using DMRS 22, and proceeds by obtaining estimates ф̂k of the CPOs фk using the PTRS 23, and finally the estimates of Hk are obtained as Ĥk = Ĥ₀exp (iф̂k).Figs. 2A-B show that the PTRS 23 are used solely for estimation of CPOs, not directly for estimation of Hk. Arguably, the PTRS 23 may be regarded as "under-exploited" as they are not used for estimation of amplitudes. A resource element dedicated to a reference symbol allows for estimation of one phase value and one amplitude value, but for a resource element occupied by PTRS 23 is only used for its phase estimation capability. Stated differently, this disclosure provides some insight found by the inventors: PTRSs are to some extent a waste of resources, such as an underexploited resource that can be utilized for data communication. It may be appreciated that the network needs to tradeoff between CPO estimation (more PTRS) and the throughput performance (less PTRS). This disclosure addresses this issue to some extent by embedding data into PTRSs.A PTRS embedding data can be seen as a PTRS modified to embed data, such as user data and / or control data. For example, the PTRS is modified by encoding data into the amplitude part of the PTRS symbol, such as by controlling the power of the PTRS.Figs. 3A-B are signalling diagrams between an example wireless device 300 and an example network node 400 illustrating example embodiments of this disclosure.Fig. 3A shows a signalling diagram between an example wireless device 300 and an example network node 400 in downlink (such as over Uu interface connecting the wireless device 300, and the network node 400 over the air) according to this disclosure.In some examples, the wireless device 300 transmits, to the network node 400, capability signaling 305 indicating to the network node 400 that the wireless device 300 is capable of receiving / transmitting PTRS embedding data according to this disclosure. In other words, the wireless device 300 indicates to the network node 400 that the wireless device 300 is capable of transmitting and / or receiving data embedded in the PTRS.In some examples, the network node 400 transmits regular PTRSs 306 (such as PTRS not embedding data) to the wireless device 300 over a Physical Downlink Control Channel (PDCCH) and / or a Physical Downlink Shared Channel (PDSCH).The network node 400 transmits, to the wireless device 300, a configuration 307 of a PTRS embedding data (such as a PTRS that embeds data, such as user data and / or control data). The configuration enables the wireless device 300 to retrieve data embedded in the PTRS in downlink (DL). For example, for a configuration 307 being aperiodic, a DCI in the PDDCH contains a flag to indicate the actual presence of PTRS-embedded data, and the rest of the time, regular PTRS are used.In some examples, the network node 400 transmits a PTRS 309 embedding data. In some examples, the data embedded in the PTRS 309 can be control data and / or user data. For example, the data can be used to assist and / or support PDCCH and / or PDSCH reception by the wireless device 300. For example, the PTRS embedding data can assist the PDCCH and PDSCH reception by providing control data in the PTRS 309 and by allowing for phase tracking. In some examples, the PDSCH data and the PTRS-embedded data may use the same configurations or different configurations, for example: the regular PDSCH configuration for data symbols and the configuration 307 for PTRS-embedded data disclosed herein.In some examples, the data embedded in the PTRS 309 can be provided in its own transport block or combined with PDSCH data to form a transport block. For example, at higher layer, the data stream can be combined into the same transport block. In some examples, the data may be decoded separately. In some examples, the data may belong to different transport blocks.The wireless device 300 can then retrieve the data embedded in the PTRS 309 using the configuration 307 that may include information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels. For example, amplitude levels can be seen as the amplitude levels of the modulation symbol, such as quantization levels. In other words, for example, the configuration 307 (and thereby information about the modulation alphabet and / or predetermined amplitude levels) can be used by the wireless device 300 to retrieve data embedded in the PTRS 309.Fig. 3B shows a signalling diagram between an example wireless device 300 and an example network node 40 in uplink (such as over Uu interface connecting the wireless device 300, and the network node 400 over the air) according to this disclosure.In some examples, the wireless device 300 transmits, to the network node 400, capability signaling 350 indicating to the network node 400 that the wireless device 300 is capable of receiving and / or transmitting PTRS embedding data according to this disclosure. In other words, the wireless device 300 indicates to the network node 400 that the wireless device 300 is capable of transmitting and / or receiving data embedded in the PTRS. In some examples, the wireless device 300 transmits, to the network node 400, assistance information indicating to the network node 400 that the wireless device 300 is capable of receiving and / or transmitting PTRS embedding data according to this disclosure.In some examples, the network node 400 receives regular PTRSs 351 (such as PTRS not embedding data) from the wireless device 300 over a Physical Uplink Control Channel (PUCCH) and / or a Physical Uplink Shared Channel (PUSCH).The network node 400 transmits, to the wireless device 300, a configuration 352 of a PTRS embedding data (such as a PTRS that embeds data, such as user data and / or control data). The configuration enables the wireless device 300 to transmit data embedded in the PTRS in uplink (UL).The wireless device 300 can then embed the data in the PTRS 354 for transmission so that the network node can retrieve the data using the configuration 352 that may include information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.In some examples, the network node 400 receives, from the wireless device 300, a PTRS 354 embedding data, e.g., via PUCCH and PUSCH. For example, for a configuration 307 being aperiodic, the scheduling PDDCH 353 may contain a DCI carrying a flag to indicate the actual presence of PTRS-embedded data in subsequence UL transmission, such as PRTS 354.Fig. 4 shows a signalling diagram between an example network node 400, an example wireless device 300 and a sidelink wireless device according to this disclosure for sidelink communication.In some examples, the wireless devices 300, 300A transmit, to the network node 400, respective capability signaling 404, 405 indicating to the network node 400 that the wireless devices 300, 300A are capable of receiving / transmitting PTRS embedding data according to this disclosure. In other words, the wireless devices 300, 300A indicate to the network node 400 their respective capability for transmitting and / or receiving data embedded in the PTRS.In some examples, the wireless devices 300, 300A communicate, in bidirectional manner, regular PTRSs 406 (such as PTRS not embedding data) between each other over a Physical Sidelink Control Channel (PSCCH) and / or a Physical Sidelink Shared Channel (PSSCH).The network node 400 transmits, to the wireless devices 300, 300A, respective configurations 407, 408 of a PTRS embedding data (such as a PTRS that embeds data, such as user data and / or control data) for sidelink. The configuration 407 enables the wireless device 300 to transmit and / or receive data embedded in the PTRS sidelink. The configuration 408 enables the wireless device 300A to retrieve and / or transmit data embedded in the PTRS sidelink.In some examples, the wireless devices 300 and 300A communicate a PTRS 409 embedding data, e.g., via PSCCH and PSSCH. For example, for aperiodic configuration, the aperiodic PTRS-embedded data transmissions can be signaled just-in-time, e.g., via SCI / PSCCH, where SCI is SL control indicator.In some examples, the network node 400 indicates to the wireless device 300 (and optionally to sidelink wireless device 300A) via a flag carried in DCI 409A over PDCCH the presence of a PTRS embedding data.In some examples, the wireless device 300 indicates to the wireless device 300A via a flag carried by Sidelink Control information 409B the presence of a PTRS embedding data, as part of the sidelink scheduling.The wireless device receiving the PTRS 410 can then retrieve the data embedded in the PTRS 410 using the configuration 407 or 408 that may include information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.Fig. 5 shows a flow-chart illustrating an example method 100, performed by a network node, for enabling communication of data to and / or from a wireless device according to the disclosure. The network node is the network node disclosed herein, such as network node 400 of Fig. 1, Figs. 3A-B, Fig. 4, and Fig. 7.In one or more example methods, the method 100 comprises receiving S102, from the wireless device, capability signalling indicative of the wireless device capability in processing the PTRS embedding data. This may allow the network node to activate the configuration of the PTRS embedding data.The method 100 comprises communicating S104, between the network node and the wireless device, a configuration of a phase tracking reference signal, PTRS, embedding data. The PTRS embedding data can be as a PTRS that is modified to include data and still enables phase tracking, e.g., tracking the CPO. In other words, the configuration can activate the PTRS embedding data and can indicate how data is to be retrieved from the PTRS. The configuration enables the wireless device to retrieve data embedded in the PTRS, and / or to transmit the PTRS embedding data. In some examples, the configuration enables the wireless device to decode, retrieve and / or receive the data as part of the PTRS in DL. In some examples, the configuration enables the wireless device to generate, encode, embed and / or include and transmit the data as part of the PTRS in UL. In some examples, the configuration enables the wireless device receiving the PTRS to decode, retrieve and / or receive the data as part of the PTRS in sidelink. In some examples, the configuration enables the wireless device to generate, encode, embed and / or include and transmit the data as part of the PTRS in sidelink to a sidelink wireless device as illustrated in Fig. 4. For example, the configuration comprises information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels that can be used by the wireless device to retrieve data embedded in the PTRS, and / or to transmit the PTRS embedding data. For example, when the wireless device receives the PTRS embedding data, the wireless device can use the configuration to retrieve the modulation alphabet and / or predetermined amplitude levels to retrieve the data embedded in the PTRS. For example, when the wireless device wants to transmit the PTRS embedding data, the wireless device can use the configuration to retrieve the modulation alphabet and / or predetermined amplitude levels to encode and / or embed the data in the PTRS and transmit the PTRS embedding data.In other words, the configuration disclosed herein allows the unexploited part (e.g., the amplitude part) of the PTRS to embed data while not affecting noticeably the phase tracking property of the PTRS. Stated differently, the additional data embedded in the PTRS comes at no cost in terms of resources, and thereby improves the spectral efficiency while maintaining phase tracking.In one or more example methods, communicating S104 the configuration of the PTRS embedding data comprises transmitting S104A, to the wireless device, the configuration of the PTRS embedding data. For example, this can enable the wireless device to embed data in PTRS in UL and to retrieve data in PTRS in DL.In one or more example methods, communicating S104 the configuration of the PTRS embedding data comprises receiving S104B, from the wireless device, the configuration of the PTRS embedding data. It may be envisaged that the wireless device transmits the configuration of the PTRS embedding data ahead of an UL PTRS embedding data so that the network node is capable of retrieving the data from the PTRS.In one or more example methods, the method 100 comprises transmitting S106, to the wireless device, the PTRS embedding the data. In one or more example methods, the PTRS enables phase tracking. For example, the phase-tracking property of the PTRS embedding data is unchanged. Put another way, the PTRS is still usable for phase tracking. Stated differently, for example, the PTRS that embeds data still enables phase tracking. For example, the phase of the PTRS is unchanged while the amplitude is modified due to the data being embedded. For example, a PTRS p * e-ix, where p is a real valued positive number representing the PTRS power, and x is the phase becomes the following when embedding data: (1 + a) * p * e-ix, where a is a positive real-valued symbol, thereby modifying the amplitude. This is illustrated by the results of Figs. 9A-B showing the negligible impact of the data embedding on the phase tracking.In one or more example methods, the PTRS embedding data comprises a real-valued symbol carrying the data. For example, the PTRS is modified from p * e-ix, (where p is a real valued positive number representing the PTRS power, and x is the phase) to be expressed as (1 + a) * p * e-ix, where a is a positive real-valued symbol. It may be appreciated that the PTRS embedding data including a real-valued symbol carrying the data allows the disclosed technique to have minimal or limited impact on the phase of the PTRS.The disclosed method allows inter alia boosting the capacity of a communication between the network node and the wireless device in uplink and downlink with no impact on the phase tracking and at no cost on the resource usage.In one or more example methods, the configuration comprises information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels. The modulation alphabet may be seen as the alphabet of a modulation scheme, that allows for encoding, generating and / or retrieving the data from the PTRS embedding data. The modulation alphabet can be seen as the set from which "a" of Equation (1 + a) * p * e-ix is selected. The predetermined amplitude levels can be seen as predetermined sample values of the amplitude of the modulation symbols into a finite set of levels for enabling encoding, generating and / or retrieving the data from the PTRS embedding data. The modulation alphabet and / or a number of pre-determined amplitude levels can be used by the wireless device to retrieve the data from the PTRS embedding data and / or to generate PTRS embedding data for transmission in UL or Sidelink. For example, the amplitude levels are used to map the amplitude of the PTRS to a corresponding symbol of a modulation alphabet used to embed the data in the PTRS.In one or more example methods, the configuration comprises a selector flag indicative of a modulation alphabet and / or a number of pre-determined amplitude levels. For example, the selector flag is a reference indicating a number of pre-determined amplitude levels (such as a modulation scheme, a release number, etc.).In one or more example methods, the configuration is part of a Downlink Control Information (DCI), and / or a semi-persistent Radio Resource Control (RRC) scheduling, and / or a period Radio Resource Control scheduling, and / or a control element of Medium Access Control (MAC). For example, the configuration of the PTRS embedding data can be done using DCI, a semi-persistent Radio Resource Control scheduling, and / or a period Radio Resource Control scheduling, and / or a control element of Medium Access Control. For example, the configuration can be provided at registration of the wireless device (e.g., via a flag), and / or can be set for periodic activation, or aperiodic activation. In some examples, the wireless device is configured to receive PTRS-embedded data, and each receiving occasion of PTRS-embedded data is triggered aperiodically, e.g., via PDCCH / DCI. For example, the PTRS symbols of the associated PDSCH are located in some (OFDM) symbols before or after the PDCCH resources themselves. For example, the wireless device knows where to find PTRS, e.g., via the configuration provided on a lower layer (e.g., via DCI, Physical Layer, RRC Layer and / or MAC layer). It may be envisaged that the configuration is performed at a layer higher than the Physical layer, and that the activation of the disclosed modified PTRS is performed at the Physical layer, such as via DCI.Optionally, PTRS can be associated with different transmission types or physical channels. In one or more example methods, the configuration indicates that the PTRS embedding data is associated with a unicast channel, a group-cast channel, a broadcast channel, a control channel, and / or a shared channel. In one or more example methods, the configuration indicates that the PTRS embedding data is associated with one or more of: a PDSCH channel, a PDCCH channel, a PUSCH channel, a PUCCH channel, a SL PSCCH channel, and a PSSCH channel. For example, the network node embeds data into PTRS and transmits the PTRS embedding the data over PDSCH channel, and / or a PDCCH channel. For example, the wireless device embeds data into PTRS and transmits the PTRS embedding the data over a PUSCH channel, a PUCCH channel, a SL PSCCH channel, and / or a PSSCH channel.In one or more example methods, the method comprises generating S105 the PTRS by S105A encoding the data in the PTRS. For example, the data can be encoded at S105A using a sequence that uses a constant total power and / or that avoids transmitting symbols with low amplitude. In one or more example methods, the method 100 comprises encoding S105A the data in the PTRS comprises selecting S105AA a symbol from a distribution associated with a modulation alphabet, such as a modulation alphabet having a finite cardinality. For example, the distribution is a uniform distribution associated with the modulation alphabet. However, any distribution can be used. In some examples, selecting the symbol may be performed by selecting a symbol from a finite list of symbols, where all symbols in the list are selected with equal probability.Fig. 6 shows a flow-chart illustrating an example method 200, performed by a wireless device, for enabling communication of data to and / or from the wireless device according to the disclosure. The wireless device is the wireless device disclosed herein, such as wireless device 300 of Fig. 1, Figs. 3A-B, Fig. 4, and Fig. 8.In one or more example methods, the method comprises transmitting S202, to the network node, capability signalling indicative of the wireless device capability in processing the PTRS embedding data. This for example corresponds to S102 of Fig. 5The method 200 comprises communicating S204 a configuration of a phase tracking reference signal, PTRS, embedding data. The configuration enables the wireless device to retrieve the data embedded in the PTRS, and / or to transmit the PTRS embedding data. In other words, the configuration can activate the PTRS embedding data and can indicate how data is to be retrieved from the PTRS. This for example corresponds to S104 of Fig. 5In some examples, the configuration enables the wireless device to decode, retrieve and / or receive the data as part of the PTRS in DL. In some examples, the configuration enables the wireless device to generate, encode, embed and / or include and transmit the data as part of the PTRS in UL. In some examples, the configuration enables the wireless device receiving the PTRS to decode, retrieve and / or receive the data as part of the PTRS in sidelink. In some examples, the configuration enables the wireless device to generate, encode, embed and / or include and transmit the data as part of the PTRS in sidelink to a sidelink wireless device as illustrated in Fig. 4.In one or more example methods, communicating S204 the configuration comprises receiving S204A the configuration from a network node (as illustrated in Figs. 3A-B) and / or from a sidelink wireless device (as illustrated in Fig. 4), e.g., so that the wireless device is capable of retrieving the data from the PTRS embedding data. This for example corresponds to S104A of Fig. 5In one or more example methods, communicating S204 the configuration comprises transmitting S204B the configuration to a network node and / or to a sidelink wireless device, e.g., so that the network node and / or the sidelink wireless device are capable of retrieving the data from the PTRS embedding data. This for example corresponds to S104B of Fig. 5In one or more example methods, the method 200 comprises communicating S206 the PTRS embedding data. In one or more example methods, the PTRS enables phase tracking.In one or more example methods, communicating S206 the PTRS embedding data comprises receiving S206A the PTRS embedding data. In one or more example methods, receiving S206A the PTRS embedding data comprises receiving S206AA the PTRS embedding data from a network node (illustrated in Fig. 3B) or from a sidelink wireless device (illustrated in Fig. 4). In one or more example methods, communicating S206 the PTRS embedding data comprises retrieving S207 (such as decoding, demodulating) the data from the PTRS based on the configuration.In one or more example methods, communicating S206 the PTRS embedding data comprises transmitting S206B, to a network node and / or to a sidelink wireless device, the PTRS embedding data. This for example corresponds to S106 of Fig. 5 for transmission of the PTRS to the network node.In one or more example methods, the PTRS embedding data comprises a real-valued symbol carrying the data. For example, the PTRS is modified from p * e-ix, (where p is a real valued positive number representing the PTRS power, and x is the phase) to be expressed as (1 + a) * p * e-ix, where a is a positive real-valued symbol, e.g. selected from a modulation alphabet having a finite cardinality It may be appreciated that the PTRS embedding data including a real-valued symbol carrying the data allows the disclosed technique to have no impact on the phase of the PTRS.In one or more example methods, the configuration comprises information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels. In one or more example methods, the configuration comprises a selector flag indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.In one or more example methods, the configuration is part of a Downlink Control Information, and / or a semi-persistent Radio Resource Control scheduling, and / or a period Radio Resource Control scheduling, and / or a control element of Medium Access Control.In one or more example methods, the configuration indicates that the PTRS embedding data is associated with a unicast channel, a group-cast channel, a broadcast channel, a control channel, and / or a shared channel.In one or more example methods, the configuration indicates that the PTRS embedding data is associated with one or more of: a PDSCH channel, a PDCCH channel, a PUSCH channel, a PUCCH channel, a PSCCH channel, and a PSSCH channel.In one or more example methods, the method 200 comprises generating S205 the PTRS by encoding S205 the data in the PTRS. For example, the data can be encoded using a sequence that uses a constant power and / or that avoids transmitting symbols with low amplitude. In one or more example methods, the method 200 comprises encoding the data in the PTRS comprises selecting a symbol from a distribution associated with a modulation alphabet, such as a modulation alphabet having a finite cardinality. For example, the distribution is a uniform distribution associated with the modulation alphabet. However, any distribution can be used. In some examples, selecting the symbol may be performed by selecting a symbol from a finite list of symbols, where all symbols in the list are selected equal probability. This for example corresponds to S105 of Fig. 5.Fig. 7 shows a block diagram of an example network node 400 according to the disclosure. The network node 400 comprises memory circuitry 401, processor circuitry 402, and a wireless interface 403. The network node 400 may be configured to perform any of the methods disclosed in Fig. 5. In other words, the network node 400 may be configured for enabling communication of data to and / or from a wireless device.The network node 400 is configured to communicate with a wireless device, such as the wireless device 300, 300A disclosed herein, using a wireless communication system.The wireless interface 403 is configured for wireless communications via a wireless communication system, such as a 3GPP system, such as a 3GPP system supporting one or more of: New Radio, NR, Long Term Evolution, LTE, Narrow-band IoT, NB-IoT, and Long-Term Evolution - enhanced Machine Type Communication, LTE-M, and 3GPP system operated in licensed bands or unlicensed bands.The network node 400 is configured to communicate (e.g., via the wireless interface 403) between the network node and the wireless device, a configuration of a phase tracking reference signal, PTRS, embedding data. The configuration enables the wireless device to retrieve data embedded in the PTRS, and / or to transmit the PTRS embedding data.Processor circuitry 402 is optionally configured to perform any of the operations disclosed in Fig. 5 (such as any one or more of S102, S104A, S104B, S105, S105A, S105B, S106). The operations of the network node 400 may be embodied in the form of executable logic routines (for example, lines of code, software programs, etc.) that are stored on a non-transitory computer readable medium (for example, memory circuitry 401) and are executed by processor circuitry 402).Furthermore, the operations of the network node 400 may be considered a method that the network node 400 is configured to carry out. Also, while the described functions and operations may be implemented in software, such functionality may also be carried out via dedicated hardware or firmware, or some combination of hardware, firmware and / or software.Memory circuitry 401 may be one or more of a buffer, a flash memory, a hard drive, a removable media, a volatile memory, a non-volatile memory, a random access memory (RAM), or other suitable device. In a typical arrangement, memory circuitry 401 may include a non-volatile memory for long term data storage and a volatile memory that functions as system memory for processor circuitry 402. Memory circuitry 401 may exchange data with processor circuitry 402 over a data bus. Control lines and an address bus between memory circuitry 401 and processor circuitry 402 also may be present (not shown in Fig. 7). Memory circuitry 401 is considered a non-transitory computer readable medium.Memory circuitry 401 may be configured to store a configuration of a PTRS embedding data, PTRS, real-valued symbol, information indicative of a modulation alphabet, a number of pre-determined amplitude levels, data, and / or a symbol from a distribution associated with a modulation alphabet in a part of the memory.Fig. 8 shows a block diagram of an example wireless device 300 according to the disclosure. The wireless device 300, 300A comprises memory circuitry 301, processor circuitry 302, and a wireless interface 303. The wireless device 300 may be configured to perform any of the methods disclosed in Fig. 6. In other words, the wireless device 300 may be configured for enabling communication of data to and / or from a wireless device.The wireless device 300, 300A is configured to communicate (e.g., via the wireless interface 303) a configuration of a phase tracking reference signal, PTRS embedding data. The configuration enables the wireless device to retrieve the data embedded in the PTRS, and / or to transmit the PTRS embedding data.The wireless interface 303 is configured for wireless communications via a wireless communication system, such as a 3GPP system, such as a 3GPP system supporting one or more of: New Radio, NR, Long Term Evolution, LTE, Narrow-band IoT, NB-IoT, and Long-Term Evolution - enhanced Machine Type Communication, LTE-M, and 3GPP system operated in licensed bands or unlicensed bands.The wireless device 300, 300A is optionally configured to perform any of the operations disclosed in Fig. 6 (such as any one or more of S202, S204A, S204B, S205, S205A, S206, S206A, S206AA, S206B, S207). The operations of the wireless device 300, 300A may be embodied in the form of executable logic routines (for example, lines of code, software programs, etc.) that are stored on a non-transitory computer readable medium (for example, memory circuitry 301) and are executed by processor circuitry 302).Furthermore, the operations of the wireless device 300, 300A may be considered a method that the wireless device 300, 300A is configured to carry out. Also, while the described functions and operations may be implemented in software, such functionality may also be carried out via dedicated hardware or firmware, or some combination of hardware, firmware and / or software.Memory circuitry 301 may be one or more of a buffer, a flash memory, a hard drive, a removable media, a volatile memory, a non-volatile memory, a random access memory (RAM), or other suitable device. In a typical arrangement, memory circuitry 301 may include a non-volatile memory for long term data storage and a volatile memory that functions as system memory for processor circuitry 302. Memory circuitry 301 may exchange data with processor circuitry 302 over a data bus. Control lines and an address bus between memory circuitry 301 and processor circuitry 302 also may be present (not shown in Fig. 8). Memory circuitry 301 is considered a non-transitory computer readable medium.Memory circuitry 301 may be configured to store information (such as a configuration of a PTRS embedding data, PTRS, a real-valued symbol carrying the data, information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels) in a part of the memory.Figs. 9A-B shows graphs illustrating example numerical results according to this disclosure.To demonstrate the maintenance of the phase tracking by PTRSs embedding data and the enhanced rate or throughput, the following is provided: Let p denote the PTRS at any arbitrary resource element. For normalization purposes, without loss of generality, it is assumed that p = 1. For simplicity, the disclosed technique may be seen as proposing to replace the PTRS p with q = p + a = 1 + a where a is an information symbol carrying data to be demodulated at the receiver (e.g., the wireless device in downlink, the network node in uplink, and / or a sidelink wireless device in sidelink).In some examples, in order to maintain phase tracking capability, the symbol a is real-valued and 1 + a is positive. In other words, for example, p + a has the same phase as p. To quantify the data transfer capability per PTRS, a is selected such that e.g.:q = 1 + a ~ U[A1, A2] (1)where U[a, b] denotes a uniform probability density function between a and b, A1 and A2 denote the limits of the alphabet for the symbol q.In some examples, the normalizing of the transmit power of q (e.g., expected power of q) is expressed as e.g.:E(q²) = E((1 + a)²) = (A₂³-A₁³) / (3(A₂-A₁)) (2)In some examples, setting E(q²) to unity gives that A₂ can be found for a given A₁ by solving the third order equation: A₂³ - 3A₂ = A₁³ – 3A₁. In other words, for example, A₂ can be selected accordingly, which implies that A₁may vary 0 < A₁ ≤ 1 to investigate tradeoff between data transfer and CPO tracking capabilities. Stated differently, A₁and A₂ can be selected or balanced to get an average power of 1. For example, when A₁ is 1, A₂ is 1, and q is always 1, no data is transferred. For example, as A₁lowers, more data can be embedded in the PTRS for transfer. For example, when A₁ is 0, significant data can be transmitted but phase tracking is degraded for PTRS prepared with A₁ = 0. In some examples, the uniform constellation abided to by q is representative of the rates achieved by discrete Pulse Amplitude Modulation (PAM) type constellations. However, any distribution and modulation alphabet can be used.It is assumed that the CPO can be tracked from the disclosed PTRS embedding data with the same precision as for standard PTRS not embedding data. This assumption is supported by Figs. 9A-B. In other words, Figs. 9A-B show that the assumption is valid. For simplicity, it is assumed that with standard PTRS, the channels can be perfectly estimated, i.e., Ĥk = Hk. For example, the channels at the PTRS locations are perfectly estimated, and the channel model for an arbitrary PTRS reads e.g.:y = Hq + n, (3)where H is the channel at the PTRS location and n is complex Gaussian noise with variance 1 (N₀ is absorbed into H). For example, H is known from the DMRS so the focus is on tracking the phase. For example, the channel H is assumed as a zero-mean complex Gaussian with variance γ, which leads to e.g.: H = √γh where h is complex Gaussian with variance 1. As H is assumed known, the average SNR at the PTRS location y can be rotated accordingly to obtain e.g.:z = (H* / |H|)y = √γgq + w (4)where g = |h| and is therefore Rayleigh distributed (after a scaling with √2, i.e., g is Rayleigh-distributed with scale parameter 1 / √2). The available rate (e.g., throughput, and / or data transferability), in natural units of information (nats) per channel use, for given g is, by definition, given as e.g.:I_PTRS(g) = -E_z(ln p(z)) + E_z,a(ln(p(z|a))) (5)Where, after a few manipulations, p can be expressed as e.g.:p(z) = (erf(z-A₁g)-erf(z-A₂g)) / (2g√π(A₂-A₁)) (6)In some examples, averaging the rate per PTRS I_PTRS(g) over g gives, for a given value γ, e.g.:Ī_PTRS = E_g(I_PTRS(g)) (7)Figs. 9A-B show results in terms of average rate per PTRS, Ī_PTRS.In some examples, as illustrated in Figs. 9A-B, the expectations can be evaluated through Monte Carlo computation and with an estimator for phase tracking that is the same for PTRS embedding data and PTRS not embedding data and is not aware of the change on the PTRS.For showing that the CPO tracking capability is not significantly degraded, T PTRSs are assumed to be in the time-domain. For example, T can be in the order of e.g., 3-10. The received model at the kth PTRS reads e.g.:yk = √γhexp (i∆k)qk + nkThe CPO tracking estimator is assuming standard PTRS, that is a = 0 (no data embedded). implying q = p = 1 so ∆ is estimated on the basis of the model e.g.:yk = √γh exp(i∆k) + nk (8)A Maximum Likelihood (ML) estimator can be used and provide the estimate e.g.:∆̂ = arg min_x Σ_k=1^T |yk - √γh exp(ixk)|² (9)The estimate of Equation (9) may deteriorate in quality for the PTRS embedding data disclosed herein since the assumed model at the estimator does not coincide with the true one. It is to be noted that the quantity √γh is known from the DMRS estimation stage. Figs. 9A-B show results in terms of the root mean square, rms, error √E((∆̂ – ∆)²)) where the average SNR over the channel h (including noise) assumes a given value of the average SNR γ.Fig. 9A shows numerical results for the case γ = 10dB and T = 5. The x-axis shows the value A₁. Curve 52, with axis to the left, shows the ergodic rate that can be embedded into each PTRS. Curve 54, with axis to the right, shows the loss in rms error of the CPO slope estimate compared to unmodified PTRS.Fig. 9A shows that the loss in rms error is fairly small - less than 0.7 dB for the entire curve.With a tolerated loss of 0.2 dB, the selection of A₁can be such that A₁ ≈ 0.55 which yields a rate per PTRS of 0.35 nats. As a point of reference, at this value of γ, the ergodic rate per data resource element is around 2.01 nats.The results show that the amount of data that can be carried per PTRS resource element can carry about 17% of the data carried by the resource elements allocated for data transmission, and this is performed with insignificant impact on the phase tracking as the rms error remains negligible.Fig. 9A shows that if the phasing tracking capability is good enough, more data can be embedded, e.g., A1 = 0.2.Fig. 9B shows the same experiment as Fig. 9A but with average SNR γ = 0dB. Curve 56, with axis to the left, shows the ergodic rate that can be embedded into each PTRS. Curve 58, with axis to the right, shows the loss in rms error of the CPO slope estimate compared to unmodified PTRS.The same conclusions as Fig. 9A still apply: data can be embedded into the PTRS without any significant penalty to the rms error of CPO tracking estimation. In other words, with a lower SNR, the embedding of data in the PTRS performs well and does not impact significantly the phase tracking capability. The results are the same for a higher and lower SNR. In other words, the disclosed technique is robust against SNR variations.Examples of methods and products (network node and wireless device) according to the disclosure are set out in the following items:Item 1. A method (100), performed by a network node, for enabling communication data to and / or from a wireless device, the method comprising:- communicating (S104), between the network node and the wireless device, a configuration of a phase tracking reference signal, PTRS, embedding data, wherein the configuration enables the wireless device to retrieve data embedded in the PTRS, and / or to transmit the PTRS embedding data.Item 2. The method according to item 1, the method comprising:- transmitting (S106), to the wireless device, the PTRS embedding data.Item 3. The method according to any of the previous items, wherein the PTRS embedding data comprises a real-valued symbol carrying the data.Item 4. The method according to any of the previous items, wherein the configuration comprises information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.Item 5. The method according to any of the previous items, wherein the configuration comprises a selector flag indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.Item 6. The method according to any of the previous items, wherein the configuration is part of a Downlink Control Information, and / or a semi-persistent Radio Resource Control scheduling, and / or a period Radio Resource Control scheduling, and / or a control element of Medium Access Control.Item 7. The method according to any of the previous items, wherein the PTRS enables phase tracking.Item 8. The method according to any of the previous items, the method comprising receiving (S102), from the wireless device, capability signalling indicative of the wireless device capability in processing the PTRS embedding data.Item 9. The method according to any of the previous items, wherein the configuration indicates that the PTRS embedding data is associated with a unicast channel, a group-cast channel, a broadcast channel, a control channel, and / or a shared channel.Item 10. The method according to any of the previous items, wherein the configuration indicates that the PTRS embedding data is associated with one or more of: a PDSCH channel, a PDCCH channel, a PUSCH channel, a PUCCH channel, a SL PSCCH channel, and a PSSCH channel.Item 11. The method according to any of the previous items, wherein the method comprises generating (S105) the PTRS by encoding (S105A) the data in the PTRS.Item 12. The method according to item 11, wherein encoding (S105A) the data in the PTRS comprises selecting (S105B) a symbol from a distribution associated with a modulation alphabet.Item 13. The method according to any of the previous items, wherein communicating (S104) the configuration comprises transmitting (S104A), to the wireless device, the configuration.Item 14. The method according to any of the previous items, wherein communicating (S104) the configuration comprises receiving (S104B), from the wireless device, the configuration.Item 15. A method (200), performed by a wireless device, for enabling communication of data to and / or from the wireless device, the method comprising:- communicating (S204) a configuration of a phase tracking reference signal, PTRS, embedding data, wherein the configuration enables the wireless device to retrieve the data embedded in the PTRS, and / or to transmit the PTRS embedding data.Item 16. The method according to item 15, wherein communicating (S204) the configuration comprises receiving (S204A) the configuration from a network node or from a sidelink wireless device.Item 17. The method according to any of items 15-16, wherein communicating (S204) the configuration comprises transmitting (S204B) the configuration to a network node and / or to a sidelink wireless device.Item 18. The method according to any of items 15-17, the method comprising:- communicating (S206) the PTRS embedding data.Item 19. The method according to item 18, wherein communicating (S206) the PTRS embedding data comprises receiving (S206A) the PTRS embedding data; and wherein the method comprises:- retrieving (S207) the data from the PTRS based on the configuration.Item 20. The method according to item 19, wherein receiving (S206A) the PTRS embedding data comprises receiving (S206AA) the PTRS embedding data from a network node or from a sidelink wireless device.Item 21. The method according to any of items 18-20, wherein communicating (S206) the PTRS embedding data comprises transmitting (S206B), to a network node and / or to a sidelink wireless device, the PTRS embedding data.Item 22. The method according to any of items 15-21, wherein the PTRS embedding data comprises a real-valued symbol carrying the data.Item 23. The method according to any of items 15-22, wherein the configuration comprises information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.Item 24. The method according to any of items 15-23, wherein the configuration comprises a selector flag indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.Item 25. The method according to any of items 15-24, wherein the configuration is part of a Downlink Control Information, and / or a semi-persistent Radio Resource Control scheduling, and / or a period Radio Resource Control scheduling, and / or a control element of Medium Access Control.Item 26. The method according to any of items 15-25, wherein the PTRS enables phase tracking.Item 27. The method according to any of items 15-26, the method comprising transmitting (S202), to the network node, capability signalling indicative of the wireless device capability in processing the PTRS embedding data.Item 28. The method according to any of items 15-27, wherein the configuration indicates that the PTRS embedding data is associated with a unicast channel, a group-cast channel, a broadcast channel, a control channel, and / or a shared channel.Item 29. The method according to any of items 15-28, wherein the configuration indicates that the PTRS embedding data is associated with one or more of: a PDSCH channel, a PDCCH channel, a PUSCH channel, a PUCCH channel, a SL PSCCH channel, and a PSSCH channel.Item 30. The method according to any of items 15-29, wherein the method comprises generating (S205) the PTRS by encoding (S205A) the data in the PTRS.Item 31. A network node comprising memory circuitry, processor circuitry, and a wireless interface, wherein the network node is configured to perform any of the methods according to any of items 1-14.Item 32. A wireless device comprising memory circuitry, processor circuitry, and a wireless interface, wherein the transmitter device is configured to perform any of the methods according to any of items 15-30.The use of the terms "first", "second", "third" and "fourth", "primary", "secondary", "tertiary" etc. does not imply any particular order, but are included to identify individual elements. Moreover, the use of the terms "first", "second", "third” and “fourth”, "primary", "secondary", "tertiary" etc. does not denote any order or importance, but rather the terms "first", "second", "third" and "fourth", "primary", "secondary", "tertiary" etc. are used to distinguish one element from another. Note that the words "first", "second”, “third" and "fourth", "primary", "secondary", "tertiary" etc. are used here and elsewhere for labelling purposes only and are not intended to denote any specific spatial or temporal ordering. Furthermore, the labelling of a first element does not imply the presence of a second element and vice versa.It may be appreciated that Figures 1 to 9A-B comprise some circuitries or operations which are illustrated with a solid line and some circuitries, components, features, or operations which are illustrated with a dashed line. Circuitries or operations which are comprised in a solid line are circuitries, components, features or operations which are comprised in the broadest example. Circuitries, components, features, or operations which are comprised in a dashed line are examples which may be comprised in, or a part of, or are further circuitries, components, features, or operations which may be taken in addition to circuitries, components, features, or operations of the solid line examples. It should be appreciated that these operations need not be performed in order presented. Furthermore, it should be appreciated that not all of the operations need to be performed. The example operations may be performed in any order and in any combination. It should be appreciated that these operations need not be performed in order presented. Circuitries, components, features, or operations which are comprised in a dashed line may be considered optional.Other operations that are not described herein can be incorporated in the example operations. For example, one or more additional operations can be performed before, after, simultaneously, or between any of the described operations.Certain features discussed above as separate implementations can also be implemented in combination as a single implementation. Conversely, features described as a single implementation can also be implemented in multiple implementations separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations, one or more features from a claimed combination can, in some cases, be excised from the combination, and the combination may be claimed as any sub-combination or variation of any sub-combination.It is to be noted that the word "comprising" does not necessarily exclude the presence of other elements or steps than those listed.It is to be noted that the words "a" or "an" preceding an element do not exclude the presence of a plurality of such elements.It should further be noted that any reference signs do not limit the scope of the claims, that the examples may be implemented at least in part by means of both hardware and software, and that several "means", "units" or "devices" may be represented by the same item of hardware. Language of degree used herein, such as the terms "approximately," "about," "generally," and "substantially" as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms "approximately", "about", "generally," and "substantially" may refer to an amount that is within less than or equal to 10% of, within less than or equal to 5% of, within less than or equal to 1% of, within less than or equal to 0.1% of, and within less than or equal to 0.01% of the stated amount. If the stated amount is 0 (e.g., none, having no), the above recited ranges can be specific ranges, and not within a particular % of the value.The various example methods, devices, nodes and systems described herein are described in the general context of method steps or processes, which may be implemented in one aspect by a computer program product, embodied in a computer-readable medium, including computer-executable instructions, such as program code, executed by computers in networked environments. A computer-readable medium may include removable and non-removable storage devices including, but not limited to, Read Only Memory (ROM), Random Access Memory (RAM), compact discs (CDs), digital versatile discs (DVD), etc. Generally, program circuitries may include routines, programs, objects, components, data structures, etc. that perform specified tasks or implement specific abstract data types. Computer-executable instructions, associated data structures, and program circuitries represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.Although features have been shown and described, it will be understood that they are not intended to limit the claimed disclosure, and it will be made obvious to those skilled in the art that various changes and modifications may be made without departing from the scope of the claimed disclosure. The specification and drawings are, accordingly, to be regarded in an illustrative rather than restrictive sense. The claimed disclosure is intended to cover all alternatives, modifications, and equivalents.

Claims

1. A method (100), performed by a network node, for enabling communication of data to and / or from a wireless device, the method comprising:- communicating (S104), between the network node and the wireless device, a configuration of a phase tracking reference signal, PTRS, embedding data, wherein the configuration enables the wireless device to retrieve data embedded in the PTRS, and / or to transmit the PTRS embedding data.

2. The method according to claim 1, the method comprising:- transmitting (S106), to the wireless device, the PTRS embedding data.

3. The method according to any of the previous claims, wherein the PTRS embedding data comprises a real-valued symbol carrying the data.

4. The method according to any of the previous claims, wherein the configuration comprises information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.

5. The method according to any of the previous claims, wherein the configuration comprises a selector flag indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.

6. The method according to any of the previous claims, wherein the configuration is part of a Downlink Control Information, and / or a semi-persistent Radio Resource Control scheduling, and / or a period Radio Resource Control scheduling, and / or a control element of Medium Access Control.

7. The method according to any of the previous claims, wherein the PTRS enables phase tracking.

8. The method according to any of the previous claims, the method comprising receiving (S102), from the wireless device, capability signalling indicative of the wireless device capability in processing the PTRS embedding data.

9. The method according to any of the previous claims, wherein the configuration indicates that the PTRS embedding data is associated with a unicast channel, a group-cast channel, a broadcast channel, a control channel, and / or a shared channel.

10. The method according to any of the previous claims, wherein the configuration indicates that the PTRS embedding data is associated with one or more of: a PDSCH channel, a PDCCH channel, a PUSCH channel, a PUCCH channel, a SL PSCCH channel, and a PSSCH channel.

11. The method according to any of the previous claims, wherein the method comprises generating (S105) the PTRS by encoding (S105A) the data in the PTRS.

12. The method according to claim 11, wherein encoding (S105A) the data in the PTRS comprises selecting (S105B) a symbol from a distribution associated with a modulation alphabet.

13. The method according to any of the previous claims, wherein communicating (S104) the configuration comprises transmitting (S104A), to the wireless device, the configuration.

14. The method according to any of the previous claims, wherein communicating (S104) the configuration comprises receiving (S104B), from the wireless device, the configuration.

15. A method (200), performed by a wireless device, for enabling communication of data to and / or from the wireless device, the method comprising:- communicating (S204) a configuration of a phase tracking reference signal, PTRS, embedding data, wherein the configuration enables the wireless device to retrieve the data embedded in the PTRS, and / or to transmit the PTRS embedding data.

16. The method according to claim 15, wherein communicating (S204) the configuration comprises receiving (S204A) the configuration from a network node or from a sidelink wireless device.

17. The method according to any of claims 15-16, wherein communicating (S204) the configuration comprises transmitting (S204B) the configuration to a network node and / or to a sidelink wireless device.

18. The method according to claim 15-17, the method comprising:- communicating (S206) the PTRS embedding data.

19. The method according to claim 18, wherein communicating (S206) the PTRS embedding data comprises receiving (S206A) the PTRS embedding data; and wherein the method comprises:- retrieving (S207) the data from the PTRS based on the configuration.

20. The method according to claim 19, wherein receiving (S206A) the PTRS embedding data comprises receiving (S206AA) the PTRS embedding data from a network node or from a sidelink wireless device.

21. The method according to any of claims 18-20, wherein communicating (S206) the PTRS embedding data comprises transmitting (S206B), to a network node and / or to a sidelink wireless device, the PTRS embedding data.

22. The method according to any of claims 15-21, wherein the PTRS embedding data comprises a real-valued symbol carrying the data.

23. The method according to any of claims 15-22, wherein the configuration comprises information indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.

24. The method according to any of claims 15-23, wherein the configuration comprises a selector flag indicative of a modulation alphabet and / or a number of pre-determined amplitude levels.

25. The method according to any of claims 15-24, wherein the configuration is part of a Downlink Control Information, and / or a semi-persistent Radio Resource Control scheduling, and / or a period Radio Resource Control scheduling, and / or a control element of Medium Access Control.

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