EP4677783A1

EP4677783A1 - Uplink (ul) power control

Info

Publication number: EP4677783A1
Application number: EP23711029.1A
Authority: EP
Inventors: Niklas WERNERSSON; Anders FURUSKÄR; Claes Tidestav
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2023-03-10
Filing date: 2023-03-10
Publication date: 2026-01-14
Also published as: WO2024188440A1

Abstract

A method performed by a UE. The method includes measuring energy of a first RS resource (q_d,1) to produce a first RS measurement and measuring energy of a second RS resource (q_d,2) to produce a second RS measurement. The method also includes using the first RS measurement to produce a first transmission, Tx, power value and using the second RS measurement to produce a second Tx power value. The method also includes selecting a Tx power value from a set of Tx power values comprising the first Tx power value, the second Tx power value, and a maximum Tx power value. The method also includes performing a transmission using the selected Tx power value.

Description

UPLINK (UL) POWER CONTROL TECHNICAL FIELD Disclosed are embodiments related to uplink (UL) power control. BACKGROUND UL Power control Setting output power levels of transmitters (e.g., base stations in downlink (DL) and user equipments (UEs) in UL) in mobile systems is commonly referred to as power control (PC). Objectives of PC include improved capacity, coverage, and system robustness, as well as reduced power consumption. In New Radio (NR), UL PC mechanisms can be categorized into three groups: (i) open-loop PC, (ii) closed-loop PF, and (iii) combined open-closed-loop PC. These mechanisms differ in what input is used to determine the transmit power. In the open-loop case, the transmitter measures a signal sent from a receiver, and sets its output power based on this measurement. In the closed-loop case, the receiver measures a signal from the transmitter and, based on this measurement, sends a Transmit Power Control (TPC) command to the transmitter, which then sets the transmit power accordingly. In a combined open- and closed-loop scheme, both methods (open-loop and closed-loop) are used to set the transmit power. UL PC in NR release 15 In NR release 15 (as described in 3GPP Technical Report (TR) 38.213 v15.11.0) a UE is initially performing PC for the physical random-access channel (PRACH) transmission using the following formula: ^^_PRACH,^,^,^^ ^^^ ൌ ^^ ^^ ^^^ ^^_CMAX,^,^^ ^^^, ^^_{PRACH,target,^,^} ^ ^^ ^^_^,^,^^ [dBm], After a connection is established between the UE and a base station (e.g., eNB or gNB) the UE can be configured for performing UL PC also on other channels (e.g., the physical uplink control channel (PUCCH), the physical uplink shared channel (PUSCH)). Setting the UE transmit power for a PUCCH transmission is done using the following formula: ^^_PUCCH,^,^,^^ ^^, ^^_௨, ^^_ௗ, ^^^ ൌ ^ ^^ ^^_^,^,^^ ^^_ௗ^ by the UE. For PUSCH the UE instead uses the equation: ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^^ ൌ ^^{^} where c denotes the serving cell and ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^^ is the transmit power to use in a given transmission occasion i. For a sounding reference signal (SRS) transmission the UE transmission power is defined by: ^^_SRS,^,^,^^ ^^, ^^_^, ^^^ ൌ In the above formulas the term ^^ ^^_^,^,^ ^{^} ^^_ௗ ^{^}, are used for open loop power control whereas the three terms ^^_^,^,^^ ^^, ^^^, ^^_^,^,^^ ^^, ^^^ and ℎ_^,^,^^ ^^, ^^^ are used for closed loop power control (for PUCCH, PUSCH, and respectively). Although the formulas for PUCCH, PUSCH and SRS are different they are at high level, from the perspective of closed loop and open loop power control, quite similar. Therefore, this disclosure focuses on PUSCH UL PC, but the disclosure can easily be applied to PUCCH UL PC and SRS UL PC as well. PUSCH open loop power control The open loop PC is based on ^^ ^^_^,^,^^ ^^_ௗ^ which is a downlink pathloss estimate in dB calculated by the UE by measuring on a reference signal (RS) represented by index q _d . Hence, by measuring on this RS the UE will be able to compensate for the pathloss by adjusting its transmission power. Furthermore, by controlling the configurable parameter ^^_^,^,^^ ^^^ it is also possible to control to what extent the UE should adjust its transmission power based on the open loop power control ( ^^_^,^,^ ^{^} ^^^{^} = 0 means “no adjustment” and ^^_^,^,^^ ^^^ ൌ 1 means “full adjustment”). PUSCH closed loop power control The closed-loop PC related term ^^_^,^,^^ ^^, ^^^ can be configured to one of two modes: ^^ ^ ^^, ^^^ ൌ ^^ ^ ^^, ^^^ or ^^ ^ ∑^{^^^^^ି^} ^_{,^,^ PUSCH,^,^,^ ^,^,^} ^^, ^^^ ൌ ^^_^,^,^^ ^^ െ ^^_^, ^^^ ^ _^ୀ^ ^^_PUSCH,^,^,^^ ^^, ^^^ , the value ^^_PUSCH,^,^,^^ ^^, ^^^ is the TPC (Transmission Power Control) command value included in a DCI of format 0_0, format 0_1 or format 2_2. The possible values of ^^_PUSCH,^,^,^^ ^^, ^^^ are given in the table below. TABLE 1: Mapping of TPC Command Field in DCI format 0_0, DCI format 0_1, or DCI format 2_2. TPC Accumulated ^_{PUSCH,b, f , c} Absolute ^_{PUSCH,b, f , c} Command Field or ^_{SRS,b, f , c} [dB] or ^_{SRS,b, f , c} [dB] 0 -1 -4 1 0 -1 2 1 1 3 3 4 Hence, by using TPC the gNB will be able to impact the UE output power. Beam specific PUSCH power control NR supports beam specific UL PC by, for example, letting ^^_{O_PUSCH,^,^,^} ^{^} ^^^{^} be a function of the index j where ^^ ∈ ^{^}0, 1, ... , ^^ െ 1^{^}. Hence, in this sense different beams (represented by different values of j) may be configured with different values of ^^_{O_PUSCH,^,^,^}. Which j to use when deriving ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^^ for a given PUSCH transmission may in turn be signaled via a DCI message or via a medium access control (MAC) control element (CE). (The same holds for ^^_^,^,^^ ^^^^. Furthermore, also ^^ ^^_^,^,^^ ^^_ௗ^ may be beam specific in the sense that ^^_ௗ may be signaled to the UE with the implication that a different RS is used to perform the open loop power control. As yet another component of the “beam specific” UL PC, there may be multiple sets of also ^^_^,^,^^ ^^, ^^^ which are then controlled by the index l which can be signaled in the DL. Power headroom reporting There are different kinds of power headroom reports (PHRs) in NR assuming e.g. PUSCH-only transmission or assuming combined PUSCH and PUCCH transmission etc. As an example, type 1 PHR is given as: P^{Htype1,b, f ,c(i, j,qd,l) ^PCMAX, f ,c(i) ^ ^P ^ PUSCH} ^{O_PUSCHb,, f ,c(j) ^10log10(2 ^MRB,b, f ,c(i)) ^ ^b, f ,c(j) ^PLb, f ,c(qd) ^ ^TF,b, f ,c(i) ^ fb, f , c(i, l) ^} Network traffic may comprise a mix of packets, such as high priority packets and low priority packets. A high priority packet may have a strict requirement on latency and/or reliability, whereas a low priority packet may not have such strict requirements. The varying requirements are due to varying priority among the users, and due to requirements being different for different services (mobile broadband (MBB) vs Ultra-Reliable Low Latency Communication (URLLC) for example). SUMMARY Certain challenges presently exist. For instance, meeting a strict requirement on latency and/or reliability for a high priority packet is a challenging task. One of the challenges is that one typically would like to allow the transmission of the high priority packet occur in parallel with a transmission of a packet with lower priority, but this may cause the higher priority transmission to be interfered with by interference generated from the lower priority transmission. Accordingly, in one aspect there is provided a method performed by a UE. The method includes measuring energy of a first RS resource (q_d,1) to produce a first RS measurement and measuring energy of a second RS resource (qd,2) to produce a second RS measurement. The method also includes using the first RS measurement to produce a first transmission, Tx, power value and using the second RS measurement to produce a second Tx power value. The method also includes selecting a Tx power value from a set of Tx power values comprising the first Tx power value, the second Tx power value, and a maximum Tx power value. The method also includes performing a transmission using the selected Tx power value. In another aspect there is provided a computer program comprising instructions which when executed by processing circuitry of a UE causes the UE to perform any of the UE methods disclosed herein. In one embodiment, there is provided a carrier containing the computer program wherein the carrier is one of an electronic signal, an optical signal, a radio signal, and a computer readable storage medium. In another aspect there is provided a UE that is configured to perform the UE methods disclosed herein. The UE may include memory and processing circuitry coupled to the memory. In another aspect there is provided a method performed by a network node. The method includes deciding to schedule a first UE served by the first network node to perform a first UL transmission. The method also includes scheduling the first UE to perform the first UL transmission. The method also includes transmitting a first reference signal, RS, using a first RS resource (q_d,101), wherein the first UE uses a measurement of the energy of the first RS resource to determine a transmit, Tx, power for the first UL transmission. The method also includes, as a result of scheduling or deciding to schedule the first UE to perform the first UL transmission, transmitting a second RS using a second RS resource (q_d,1) to enable a second UE to determine a Tx power for a second UL transmission to be performed by the second UE. In another aspect there is provided a computer program comprising instructions which when executed by processing circuitry of a network node causes the apparatus to perform any of the network node methods disclosed herein. In one embodiment, there is provided a carrier containing the computer program wherein the carrier is one of an electronic signal, an optical signal, a radio signal, and a computer readable storage medium. In another aspect there is provided a network node that is configured to perform the network node methods disclosed herein. The network node may include memory and processing circuitry coupled to the memory. An advantage of the embodiments disclosed herein is that they enable a network node (e.g., a gNB) to cause an interfering UE to back off in transmit power. Thereby, the network node that schedules a high priority transmission will be able to impact interfering UEs (e.g. UEs transmitting MBB) in such a way that they back off in power. This will benefit the high priority transmission since it would increase the received signal to interference ratio for the received high priority transmission. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated herein and form part of the specification, illustrate various embodiments. FIG.1 illustrates a system according to an embodiment. FIG.2 is a message flow diagram illustrating a message flow according to an embodiment. FIG.3 is a message flow diagram illustrating a message flow according to an embodiment. FIGs.4A, 4B, 4C, and 4D show results illustrating the advantage of the embodiments. FIG.5 is a flowchart illustrating a process according to an embodiment. FIG.6 is a flowchart illustrating a process according to an embodiment. FIG.7 is a block diagram of a UE according to an embodiment. FIG.8 is a block diagram of a network node according to an embodiment. DETAILED DESCRIPTION FIG.1 illustrates a system 100 according to an embodiment. System 100 includes a first UE 101 (a.k.a., “UE A”) being served by a network node 104 (a.k.a., “gNB1”) and a second UE 102 (a.k.a., “UE B”) being served by a network node 106 (a.k.a., “gNB2”). In the example shown, UE A performs a high priority PUSCH transmission denoted PUSCHHRLLC , where HRLLC implies “high reliability low latency communication” (i.e., UE A transmit a high priority packet over PUSCH), which is received by gNB1, whereas UE B performs a non-high priority transmission, denoted PUSCHMBB, which is received by gNB2. As shown in FIG.1, gNB1 transmits an RS on a certain RS resource (denoted “q_d,101”) for UE A to measure (this RS transmission on the resource q_d,101 is denoted RS(q_d,101)). Also, gNB 2 transmits an RS on another certain RS resource (denoted “q_d,2”) for UE B to measure (this RS transmission on the resource qd,2 is denoted RS(qd,2)). Additionally, because, in the example illustrated, UE A is scheduled to perform a high priority transmission, gNB1 also transmits an RS on yet another certain resource (denoted “qd,1”) for UE B to measure (this RS transmission on the resource qd,1 is denoted RS(qd,1)). In one embodiment, the UL power control of UE B will depend on both RS(qd,1) and RS(q_d,2) in such a way that an increased level of received energy from RS(q_d,1) at UE B may decrease the PUSCH output power of UE B (in order to decrease the interference level at gNB1). This mechanism will hence protect the reception of PUSCHHRLLC at gNB1 from interference. In a similar manner, also an increased level of received energy from RS(q_d,2) at UE B may decrease the PUSCH output power of UE B. This mechanism will hence also protect the reception of PUSCHHRLLC at gNB1 from interference. As demonstrated above, in some embodiments, the UL PC is designed such that a UE depends on multiple DL RS transmissions (e.g., RS(q_d,1) and RS(q_d,2)) in such a way that: an increased level of received energy from RS(qd,1) may decrease the PUSCH output power of a UE and vice versa; and an increased level of received energy from RS(q_d,2) may decrease the PUSCH output power of a UE and vice versa. In one embodiment, a parameter value (denoted “b”) (e.g., a single bit or multiple bits) is signaled to a UE and the UE selects, based on the value of b, a control loop for determining its UL transmit power. As one example, if b=true, then the UE uses Eq.1 to determine its UL transmit power, otherwise it uses Eq.2: ^_{^PUSCH ൌ ^^ ^^ ^^} ^{^} _{^^CMAX, ^ ^^O ^ ^^ ^^ ^ ^^ௗ^^} ^{^} _{[dBm] (Eq. 1)} ^^_PUSCH ൌ ^^ ^^ ^^^ ^^_CMAX, ^ ^^_O ^ ^^ ^^ ^ ^^_ௗ,^^^, ^ ^^_O െ ∆ ^ ^^ ^^ ^ ^^_ௗ^^^ [dBm] (Eq.2) where P_CMAX, ∆, and Po are configurable, and PL(qd) is a path loss value determined based on a measurement of an RS transmitted using resource qd (e.g., qd = qd,2) and PL(qd,1) is a path loss value determined based on a measurement of an RS transmitted using the resource q_d,1. For example, a gNB scheduling a high priority PUSCH transmission may decide that the UE scheduled for the high priority transmission should use a certain power control loop by signaling b=true to the UE, and transmit a non-zero power RS using resource q_d,1 (i.e., transmits RS(q_d,1)). This will imply that the UE will perform standard UL power control whereas other (interfering) UEs that rely both on RS(qd,1) and RS(qd) (e.g., Eq.2) may perform a power backoff on PUSCH power due to the received non-zero energy from RS(q_d,1). As another example, the UEs are configured to use equation 1 as a default. In this scenario, a gNB scheduling a high priority transmission sends a message to a neighboring gNB to alert the neighboring gNB that a high priority transmission is scheduled (the message may also indicate the resources scheduled for the transmission) and the neighboring gNB instructs one or more of the UEs that it is serving to use equation 2 instead of the default. FIG.2 is a message flow diagram (a.k.a., signalling diagram) illustrating an embodiment. In a first step, gNB2 configures UE B with the parameters related to the UL PC. While the example above in FIG.1 illustrates one gNB (gNB1) transmitting RS(qd,1) there may be multiple gNBs, serving multiple UEs, configured to transmit an RS using RS resource qd,1 (i.e., same time and frequency resource). In a second step, gNB2 configures UE B with RS parameters. But in some embodiments, gNG2 configures UE B with RS parameters at same time that gNB2 configures UE B with PC parameters (e.g., a single configuration message can contain both sets of parameters). In 3GPP NR, PC parameters and RS parameters are sent from the eNode-B to the UE using the Radio Resource Control (RRC) protocol. Specifically, desired received power levels (P0) and RS Ids for pathloss measurements are included in the PUSCH-PowerControl information element. Signaling for the embodiments can be implemented by introducing additional such parameters for the allowed interference power and RS(qd,1). In one embodiment RS(q_d,2) is transmitted on a set of non-zero power CSI-RS resources and RS(qd,1) is transmitted on a set of zero power (ZP) CSI-RS resources and the set of ZP CSI-RS resources corresponds to an interference measurement resource (CSI-IM). In this case RS(q_d,1) will consequently correspond to a CSI-IM transmission. In one embodiment UE B is configured with information on how to measure and process the signal received RS resource qd,1. UE B may for instance limit the amount of time filtering allowed when estimating the received signal strength and/or a value related to the path loss based on RS(q_d,1) to allow the estimate to be able to follow rapid changes in the signal level (this may be controlled by a functionality similar to time domain measurement restriction for the channel measurements as specified by 3GPP). In an alternative embodiment the functionality may instead limit the amount of fluctuation in the estimates based on RS(q_d,1). In a third step, gNB2 configures UE B to use one of two or more UL power control loops using the framework for beam specific power control as previously described. It is noted that as will be presented below, the framework of UL power control is in some embodiments extended to depend on a larger set of parameters, e.g. ^^_PUSCH,^,^,^^ ^^, ^^_ଶ, ^^_ௗ,ଶ, ^^_ଶ, ^^_^, ^^_ௗ,^, ^^_^^ instead of ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ, ^^^, and the signalling via a to be adjusted to carry this additional information. Parts of the information may be signalled though an SRS resource indicator (SRI). In a fourth step, gNB2 transmits RS(qd,2) and gNB1 transmits RS(qd,101) and RS(qd,1). In a fifth step, UE B derives its UL power. More specifically, UE B estimates a first pathloss (e.g., ^^ ^^_^,^,^^ ^^^), or a first value related to pathloss, for each transmitted RS k (e.g., for RS(qd,1) and RS(qd,2) in the example shown in FIG.1). These values are then used to set the PUSCH power as e.g.: ^^_PUSCH,^,^,^^ ^^, ^^_ଶ, ^^_ௗ,ଶ, ^^_ଶ, ^^_^, ^^_ௗ,^, ^^_^^ ൌ Hence, an extended UL power control framework is used where the PUSCH power is set not only relative one gNB (or RS) but instead multiple gNBs (or RSs). In another embodiment: ^^_PUSCH,^,^,^^ ^^, ^^_ଶ, ^^_ௗ,ଶ, ^^_^, ^^_ௗ,^, ^^^ ൌ ^^_CMAX,^,^^ ^^^, ^_^^ ^{^} power control loops, or ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ,ଶ, ^^_ଶ, ^^_ௗ,^, ^^_^^ ൌ ^^_CMAX,^,^^ ^^^, ^ may two _{O_PUSCH,^,^,^} ^^, may be different to ^^_{O_PUSCH,^,^,^}^ ^^, 1^. In yet another embodiment one would use: ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^ ^ ൌ ^^_CMAX,^,^^ ^^^, m_{aps , to , ௗ ,} Considering e.g. ^^_{O_PUSCH,^,^,^} it will hence be given as ^^_{O_PUSCH,^,^,^}൫ ^^^ ^^^൯. In an a_{lternative embodiment ^^O_PUSCH,^,^,^^ ^^^ ^^^^ is instead replaced with ^^O_PUSCH,^,^,^} ^{^} _^^ ^{^} _{^ Δ^} meaning that an offset between the different power levers are specified. The above embodiments will result in an UL PC based on two gNBs (or RSs). The invention is however also applicable for more than two gNBs (or RSs) by simply adopting the formulas above. In one embodiment the UE can also be configured to use one power control loop that is based on one gNB (or one RS), as in prior art, and another power control loop that uses two gNBs (or RSs) as illustrated by the embodiments above. In a similar embodiment, a bit b is signaled from the gNB to UE B where b=true implies that the UE should use power control loop that is based on one RS transmission whereas b=false implies that the UE should use power control loop that is based on two RS transmissions. This may hence result in ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^ , ^^^ given from: ^_, ^{^} ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^ ^ ൌ ^ ^_^^^ if b=true ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^ ^ ൌ ^^_PUSCH,1^ ^^, ^^, ^^_ௗ , ^^ ^ [dBm] ^{^} _{may depend on different number} of reference signals. In yet another embodiment: if b=true ^_^PUSCH,^,^,^ ^{^} _{^^, ^^, ^^ௗ , ^^} ^{^} _ൌ ^^_CMAX,^,^^ ^^^, ^_, ^{^} else if b=false ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^ ^ ൌ ì ^^_CMAX,^,^^ ^^^, ï ^^^ ^ 10 ^^ ^^ ^^ ^2^ఓ ⋅ ^^^{PUSCH ü} ^ ^^^^ ^ ^^^ ⋅ ^^ ^^ ^ െ _ï ^^ ^^ ^^ _{^^ ௗ} ^^^ ^^^^ ⋅ ^^ ^^^ ^^_ௗ^^ ý ï þ Supporting UL MU-MIMO In yet another embodiment, b is not a single bit but is multiple bits b’ that can signal more than two states (e.g., three states: 00, 01, 11) where: b’ = 00 corresponds to b=false above, b’ = 01 corresponds to b=true above, AND b’ = 11 is described below. For b’ = 11: ^^_PUSCH,^,^,^^ ^^, ^^, ^^_ௗ , ^^ ^ ൌ ^^_CMAX,^,^^ ^^^, ^_{^, ^^^} level considering that a part of the signal level should be excluded. As an example, it may be so that the signal received at RS(q_d,1) minus the signal level received at RS(q_d,101) is used to estimate the path loss. In a sixth step, UE B transmits PUSCHMBB using the derived power. Power headroom report (PHR) In one embodiment, type 1 PHR may be computed as follows: ^^{^ ^^type1,b,f,c^ ^^, ^^, ^^ௗ , ^^^ ൌ ^^CMAX,^,^^ ^^^-} ^_^^ PUCCH, SRS and PRACH power control Although the examples above have been presented for PUSCH power control, this disclosure is applicable also for PUCCH, SRS and PRACH power control. FIG.3 is a message flow diagram illustrating a message flow according to an embodiment. As illustrated in FIG.3, gNB1 and gNB2 provide to UE A and UE B, respectively, UL PC parameters and RS parameters. For this embodiment, it is assumed that: ^^_{O_PUSCH, ^^,^,^}൫ ^^^ ^^^൯ ൌ ^^_{O_PUSCH, ^^,^,^}^ ^^^ െ ∆; ^^_^,^,^^ ^^^ ൌ ^^_^,^,^൫ ^^^ ^^^൯ ൌ 1; ^^^ ^^_ௗ^ ൌ ൌ ^_^PUSCH,^,^,^ ^{^} _{^^, ^^, ^^ௗ , ^^} ^{^} _{ൌ ^^ ^^ ^^^ ^^CMAX,^,^} ^{^} _^^ ^{^} _{, ^ ^^O_PUSCH,^,^,^^ ^^^ ^ ^^ ^^^,^,^^ ^^ௗ^^, ^ ^^O_PUSCH,^,^,^^ ^^^ െ ∆ ^} ^^ [dBm]. ^^_PUSCH,^,^,^൫ ^^, ^^, ^^_ௗ,^^^, ^^ , ^^൯) whereas UE B is configured to use RS ^^_ௗ ൌ ^^_ௗ,ଶ (hence . Both UEs, in this example, are configured to use the same RS ^^^ ^^_ௗ^= ^^_ௗ,^ for the last part of the UL PC equation. In one embodiment this RS corresponds gNB1 and gNB2 also provide information (the above mentioned b parameter) to UE A and UE B, respectively, to control which power loop to employ. In some embodiments, the parameterb is used to prevent a given UE from implementing a PUSCH power backoff based on the received power of RS(qd,1). For example, ifb=true, the UE is prevented from implementing a power backoff and if b=false the UE may perform a power backoff. Furthermore,b=true may be used for UEs performing high priority packet transmission whereas b=false is used for UEs performing lower priority packet transmission. This means that RS(qd,1) consequently can be used by a given gNBs to generate a power backoff of the UEs currently allowed to do so by transmitting a non-zero power signal for RS(q_d,1). The gNB may therefore chose to transmit at RS(qd,1) when a high priority packet is about to be transmitted. gNB1 then transmits an RS on q_d,101 to enable UE A, which in this example is scheduled for a high priority transmission, to determine a pathloss value (i.e., a value indicative of a path loss, such as, for example, a path loss estimate) and use the pathloss value to set its transmit power. Because UE A is scheduled for a high priority transmission, gNB1 also transmits RS(q_d,1) and signals b=false to UE A. This implies that if any other gNB is transmitting on RS(qd,1) this will not impact the derivation of ^^_PUSCH,^,^,^൫ ^^, ^^, ^^_ௗ,^^^, ^^ ൯ as used by UE A. Consequently, transmissions from other gNBs do not lead to a power backoff when performing PUSCH transmission for the high priority packet. If none of the UEs served by gNB1 are scheduled for a high priority transmission, then gNB1 would not perform any transmission on RS(q_d,1) (i.e., gNB1 is muted with respect to RS(q_d,1)) and signal b=true to UE A. This implies that if any other gNB is transmitting on RS(q_d,1) this will impact the derivation of ^^_PUSCH,^,^,^൫ ^^, ^^, ^^_ௗ,^^^, ^^ ൯ as used by UE A. Consequently, this may result in a power backoff, when performing PUSCH transmission, if the measured level of RS(q_d,1) is high enough. gNB2 transmits on RS(qd,2) and does not perform any transmission on RS(qd,1); also gNB2 is muted with respect to RS(q_d,1). UE B is configured to transmit MBB and gNB2 will then signalb=false to the UE B. This implies that if any other gNB is transmitting on RS(q_d,1) this will impact the derivation of ^^_PUSCH,^,^,^൫ ^^, ^^, ^^_ௗ,ଶ, ^^ ൯ as used by UE B. That is, the signal received on RS(q_d,1) from gNB1 will impact the derivation of ^^_PUSCH,^,^,^൫ ^^, ^^, ^^_ௗ,ଶ, ^^ ൯ as used by UE B. Consequently, this may result in a power backoff for UE B, when performing PUSCH transmission, if the measured level of RS(qd,1) is high enough. In case UE A also would need to transmit MBB type of traffic in addition to high- priority traffic, gNB1 could use the three-level signaling as introduced earlier. Hence, for the MBB part the gNB could signal b=11. In another embodiment, in case that there, for example, are only MBB types of traffic, gNB1 may transmit on RS(qd,1) when scheduling (or deciding to schedule an MBB type transmission) and gNB2 may transmit an RS on a new RS resource denoted qd,3 when scheduling (or deciding to schedule an MBB type transmission). This could hence potentially improve the UL performance since UEs generating large amounts of interference when performing PUSCH transmission would perform a power backoff. Here, however, UE A would need to be configured to measure on RS resource qd,3. Configuring, and reusing, these reference signal resources would hence need to be planned at network level. In the above embodiment, the transmission on RS(q_d,1) was dynamic in the sense that it was turned on and off and followed the traffic pattern. In another embodiment the transmissions are instead static or semi-static. In another embodiment the transmission instead follows a planned or predicted traffic pattern. Advantages FIGs.4A, 4B, 4C, and 4D illustrate the effect of the embodiments. The pathloss formula from TR.38.901 (LOS propagation UMa at 3.5 GHz) is used to translate distance to pathloss. It is assumed that ^^_CMAX,^,^=20dBm for the UEs and that they have been configured according to the previous embodiment where ^^_{O_PUSCH, ^^,^,^} ^{^} ^^^{^} has been chosen to get a received SNR of 10dB and ^=10 dB has been chosen to get a received signal to interference ratio (SIR) of 10dB for the high priority packet. In FIG.4A and 4B the transmit power of UE B is studied. In FIG.4A, we have UE B’s transmit power when b=true (or as in prior art). As can be seen the transmit power will only relate to distance to gNB2 which means that the interference generated towards gNB1 will not impact the transmit power. In FIG.4B,b=false assuming that gNB1 is transmitting on RS(qd,1). As can be seen the transmit power will be limited when gNB1 is close to UE B which in turn will limit the interference generated towards gNB1. For the perspective of the link between UE B and gNB2 there will be a cost of this in some cases since the received signal at gNB2 will become weaker than in FIG.4A. FIGs.4C and 4B shows received SIR at gNB1. It is here assumed that distance between UE B and gNB2 is large enough so that UE B would need to transmit with a high power to reach gNB2 (it may e.g. be located on cell edge). FIG.4C shows gNB1’s SIR when b=true for UE B; as can be seen the interference generated from UE B substantially limits the gNB1 SIR if the distance between UE B and gNB1 is small. FIG.4D shows the situation when b=false for UE B. As can be seen in FIG.4D, the gNB1 SIR is high also when the distance between UE B and gNB1 is small because UE B will limit its output power. This will consequently benefit the transmission of the HRLLC packet from UE A to gNB1. FIG.5 is a flow chart illustrating a process 500 according to an embodiment that is performed by a UE (e.g. UE 102). Process 500 may begin in step s502. Step s502 comprises measuring energy of a first RS resource (q_d,1) to produce a first RS measurement and measuring energy of a second RS resource (qd,2) to produce a second RS measurement. Step s504 comprises using the first RS measurement to produce a first Tx power value and using the second RS measurement to produce a second Tx power value. Step s506 comprises selecting a Tx power value from a set of Tx power values comprising the first Tx power value, the second Tx power value, and a maximum Tx power value. Step s508 comprises performing a transmission using the selected Tx power value. In some embodiments, selecting a Tx power value from the set of Tx power values comprises: selecting the first Tx power value if Tx1 ≤ Tx2 and Tx1 ≤ Tmax, where Tx1 is the first Tx power value, Tx2 is the second Tx power value and Tmax is the maximum Tx power value, selecting the second Tx power value if Tx2 ≤ Tx1 and Tx2 ≤ Tmax, or selecting the maximum Tx power value if Tmax ≤ Tx1 and Tmax ≤ Tx2. In some embodiments using the first RS measurement to produce a first Tx power value comprises: using the first RS measurement to produce a first value indicative of a first path loss; and using the first value to produce the first Tx power value. In some embodiments using the second RS measurement to produce a second Tx power value comprises: using the second RS measurement to produce a second value indicative of a second path loss; and using the second value to produce the second Tx power value. In some embodiments process 500 also includes receiving, from a network node, a control message comprising a power control (PC) mode indicator, wherein as a result of determining that the PC mode indicator indicates a first power control mode, the UE performs the step of selecting a Tx power value from said set of Tx power values comprising the first Tx power value, the second Tx power value, and the maximum Tx power value, or as a result of determining that the PC mode indicator indicates a second power control mode, the UE performs the step of selecting a Tx power value from a set of Tx power values comprising the second Tx power value and the maximum Tx power value, but not comprising the first Tx power value. In some embodiments the network node transmitted an RS using the second RS resource, and another network node transmitted an RS using the first RS resource. In some embodiments the UE is served by the network node but not the another network node. In some embodiments process 500 also includes, prior to measuring the energy of the first RS resource, receiving, from the network node, a configuration message comprising information identifying the first RS resource. FIG.6 is a flow chart illustrating a process 600 according to an embodiment that is performed by a first network node (e.g., network node 104). Process 600 may begin in step s601. Step s601 comprises deciding to schedule a first UE (e.g., UE 101) served by the first network node to perform a first UL transmission. Step s602 comprises scheduling the first UE to perform the first UL transmission. Step s604 comprises transmitting a first RS using a first RS resource (q_d,101), wherein the first UE uses a measurement of the energy of the first RS resource to determine a Tx power for the first UL transmission. Step s606 comprises as a result of scheduling or deciding to schedule the first UE to perform the first UL transmission, transmitting a second RS using a second RS resource (q_d,1) to enable a second UE (e.g., UE 102) to determine a Tx power for a second UL transmission to be performed by the second UE. In some embodiments the second UE is served by a second network node (e.g., gNB 106). In some embodiments process 600 also includes transmitting to the first UE a control message comprising a power control, PC, mode indicator, wherein the PC mode indicator indicates a first PC mode in which the first UE does not use a measurement of the second RS resource (qd,1) to determine the Tx power for the scheduled first UL transmission. In some embodiments the first UL transmission is a high-priority UL transmission. In some embodiments process 600 also includes, prior to scheduling the first UE, transmitting to the first UE a configuration message comprising information identifying the second RS resource (q_d,1). FIG.7 is a block diagram of a UE 700 (e.g., UE 101 or UE 102), according to some embodiments. As shown in FIG.7, UE 700 may comprise: processing circuitry (PC) 702, which may include one or more processors (P) 755 (e.g., one or more general purpose microprocessors and/or one or more other processors, such as an application specific integrated circuit (ASIC), field-programmable gate arrays (FPGAs), and the like); communication circuitry 748, which is coupled to an antenna arrangement 749 comprising one or more antennas and which comprises a transmitter (Tx) 745 and a receiver (Rx) 747 for enabling UE 700 to transmit data and receive data (e.g., wirelessly transmit/receive data); and a storage unit (a.k.a., “data storage system”) 708, which may include one or more non- volatile storage devices and/or one or more volatile storage devices. In embodiments where PC 702 includes a programmable processor, a computer readable storage medium (CRSM) 742 may be provided. CRSM 742 may store a computer program (CP) 743 comprising computer readable instructions (CRI) 744. CRSM 742 may be a non-transitory computer readable medium, such as, magnetic media (e.g., a hard disk), optical media, memory devices (e.g., random access memory, flash memory), and the like. In some embodiments, the CRI 744 of computer program 743 is configured such that when executed by PC 702, the CRI causes UE 700 to perform steps described herein (e.g., steps described herein with reference to the flow charts). In other embodiments, UE 700 may be configured to perform steps described herein without the need for code. That is, for example, PC 702 may consist merely of one or more ASICs. Hence, the features of the embodiments described herein may be implemented in hardware and/or software. FIG.8 is a block diagram of a network node 800 (e.g., network node 104 or network node 106), according to some embodiments for performing the methods disclosed herein. As shown in FIG.8, network node 800 may comprise: processing circuitry (PC) 802, which may include one or more processors (P) 855 (e.g., a general purpose microprocessor and/or one or more other processors, such as an application specific integrated circuit (ASIC), field- programmable gate arrays (FPGAs), and the like), which processors may be co-located in a single housing or in a single data center or may be geographically distributed (i.e., the network node 800 may be a distributed computing apparatus); a network interface 868 comprising a transmitter (Tx) 865 and a receiver (Rx) 867 for enabling network node 800 to transmit data to and receive data from other nodes connected to a network 110 (e.g., an Internet Protocol (IP) network) to which network interface 868 is connected; communication circuitry 848 (e.g., radio transceiver circuitry comprising an Rx 847 and a Tx 845) coupled to an antenna system 849 for wireless communication with UEs or other nodes; and a storage unit (a.k.a., “data storage system”) 808, which may include one or more non-volatile storage devices and/or one or more volatile storage devices. In embodiments where PC 802 includes a programmable processor, a computer readable storage medium (CRSM) 842 may be provided. CRSM 842 may store a computer program (CP) 843 comprising computer readable instructions (CRI) 844. CRSM 842 may be a non-transitory computer readable medium, such as, magnetic media (e.g., a hard disk), optical media, memory devices (e.g., random access memory, flash memory), and the like. In some embodiments, the CRI 844 of computer program 843 is configured such that when executed by PC 802, the CRI causes network node 800 to perform steps described herein (e.g., steps described herein with reference to one or more flow charts). In other embodiments, network node 800 may be configured to perform steps described herein without the need for code. That is, for example, PC 802 may consist merely of one or more ASICs. Hence, the features of the embodiments described herein may be implemented in hardware and/or software. Conclusion As the above demonstrates, with respect to a UE, the embodiments extend the UL PC framework such that: i) the PUSCH power can be derived based on measurements on multiple different reference signals; ii) there are different modes for how to derive the PUSCH power; for at least one first mode a subset of reference signals is used compared to a second mode, iii) a UE can be instructed to switch between different modes through signaling from a network node (e.g., the UE’s serving gNB); iv) at least one of the multiple different reference signals corresponds to a zero power (ZP) CSI-RS and/or a CSI-IM transmission; v) the UE may be configured with information on how to measure and process the signal received (e.g limiting the time filtering time). With respect to a network node, the embodiments extend the UL PC framework such that when the network node schedules a higher priority packet, the network node: i) signals to the UE to use the first PUSCH power control mode to derive PUSCH power and ii) transmits a signal on at least one of the reference signals used by a second PUSCH power control mode and that are not used by the first mode. When the network node schedules a lower priority packet, the gNB signals to the UE to use the second mode PUSCH power control to derive PUSCH power and does not transmit a signal on the “at least one of the reference signals used by the second PUSCH power control mode and that are not used by the first mode.” The network node transmits a signal on at least some of the reference signals used by the first PUSCH power control mode regardless of traffic type. While various embodiments are described herein, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of this disclosure should not be limited by any of the above-described exemplary embodiments. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context. As used herein transmitting a message “to” or “toward” an intended recipient encompasses transmitting the message directly to the intended recipient or transmitting the message indirectly to the intended recipient (i.e., one or more other nodes are used to relay the message from the source node to the intended recipient). Likewise, as used herein receiving a message “from” a sender encompasses receiving the message directly from the sender or indirectly from the sender (i.e., one or more nodes are used to relay the message from the sender to the receiving node). Further, as used herein “a” means “at least one” or “one or more.” Additionally, while the processes described above and illustrated in the drawings are shown as a sequence of steps, this was done solely for the sake of illustration. Accordingly, it is contemplated that some steps may be added, some steps may be omitted, the order of the steps may be re-arranged, and some steps may be performed in parallel.

Claims

CLAIMS 1. A method (500) performed by a user equipment, UE (102), the method comprising: measuring (s502) energy of a first RS resource (qd,1) to produce a first RS measurement and measuring energy of a second RS resource (qd,2) to produce a second RS measurement; using (s504) the first RS measurement to produce a first transmission, Tx, power value and using the second RS measurement to produce a second Tx power value; selecting (s506) a Tx power value from a set of Tx power values comprising the first Tx power value, the second Tx power value, and a maximum Tx power value; and performing (s508) a transmission using the selected Tx power value. 2. The method of claim 1, wherein selecting a Tx power value from the set of Tx power values comprises: selecting the first Tx power value if Tx1 ≤ Tx2 and Tx1 ≤ Tmax, where Tx1 is the first Tx power value, Tx2 is the second Tx power value and Tmax is the maximum Tx power value, selecting the second Tx power value if Tx2 ≤ Tx1 and Tx2 ≤ Tmax, or selecting the maximum Tx power value if Tmax ≤ Tx1 and Tmax ≤ Tx2. 3. The method of any one of claims 1-2, wherein using the first RS measurement to produce a first Tx power value comprises: using the first RS measurement to produce a first value indicative of a first path loss; and using the first value to produce the first Tx power value. 4. The method of any one of claims 1-3, wherein using the second RS measurement to produce a second Tx power value comprises: using the second RS measurement to produce a second value indicative of a second path loss; and using the second value to produce the second Tx power value. 5. The method of any one of claims 1-4, further comprising: receiving, from a network node (106), a control message comprising a power control, PC, mode indicator, wherein as a result of determining that the PC mode indicator indicates a first power control mode, the UE performs the step of selecting a Tx power value from said set of Tx power values comprising the first Tx power value, the second Tx power value, and the maximum Tx power value, or as a result of determining that the PC mode indicator indicates a second power control mode, the UE performs the step of selecting a Tx power value from a set of Tx power values comprising the second Tx power value and the maximum Tx power value, but not comprising the first Tx power value. 6. The method of claim 5, wherein the network node (106) transmitted an RS using the second RS resource, and another network node (104) transmitted an RS using the first RS resource. 7. The method of claim 6, wherein the UE is served by the network node (106) but not the another network node (104). 8. The method of any one of claims 5-7, further comprising: prior to measuring the energy of the first RS resource, receiving, from the network node (106), a configuration message comprising information identifying the first RS resource. 9. A method performed by a first network node (104), the method comprising: deciding (s601) to schedule a first user equipment, UE (101), served by the first network node to perform a first uplink, UL, transmission; scheduling (s602) the first UE to perform the first UL transmission; transmitting (s604) a first reference signal, RS, using a first RS resource (qd,101), wherein the first UE uses a measurement of the energy of the first RS resource to determine a transmit, Tx, power for the first UL transmission; and as a result of scheduling or deciding to schedule the first UE to perform the first UL transmission, transmitting a second RS using a second RS resource (qd,1) to enable a second UE (102) to determine a Tx power for a second UL transmission to be performed by the second UE (102). 10. The method of claim 9, wherein the second UE (102) is served by a second network node (106). 11. The method of claim 9 or B2, further comprising: transmitting to the first UE a control message comprising a power control, PC, mode indicator, wherein the PC mode indicator indicates a first PC mode in which the first UE does not use a measurement of the second RS resource (qd,1) to determine the Tx power for the scheduled first UL transmission. 12. The method of any one of claims 9-11, wherein the first UL transmission is a high- priority UL transmission. 13. The method of any one of claims 9-12, further comprising: prior to scheduling the first UE, transmitting to the first UE a configuration message comprising information identifying the second RS resource (q_d,1). 14. A computer program (743) comprising instructions (744) which when executed by processing circuitry (702) of a user equipment (700, 101, 102) causes the UE to perform the method of any one of claims A1-A8. 15. A computer program (843) comprising instructions (844) which when executed by processing circuitry (802) of a network node (800, 104, 106) causes the network node to perform the method of any one of claims 9-B5. 16. A carrier containing the computer program of claim 14 or 15, wherein the carrier is one of an electronic signal, an optical signal, a radio signal, and a computer readable storage medium (742, 842). 17. A user equipment, UE (102), the UE being configured to perform a method comprising: measuring (s502) energy of a first RS resource (qd,1) to produce a first RS measurement and measuring energy of a second RS resource (qd,2) to produce a second RS measurement; using (s504) the first RS measurement to produce a first transmission, Tx, power value and using the second RS measurement to produce a second Tx power value; selecting (s506) a Tx power value from a set of Tx power values comprising the first Tx power value, the second Tx power value, and a maximum Tx power value; and performing (s508) a transmission using the selected Tx power value. 18. The UE of claim 17, wherein the UE is further configured to perform the method of any one of claims 2-8. 19. A first network node (104), the first network node being configured to perform a method comprising: deciding (s601) to schedule a first user equipment, UE (101), served by the first network node to perform a first uplink, UL, transmission; scheduling (s602) the first UE to perform the first UL transmission; transmitting (s604) a first reference signal, RS, using a first RS resource (q_d,101), wherein the first UE uses a measurement of the energy of the first RS resource to determine a transmit, Tx, power for the first UL transmission; and as a result of scheduling or deciding to schedule the first UE to perform the first UL transmission, transmitting a second RS using a second RS resource (qd,1) to enable a second UE (102) to determine a Tx power for a second UL transmission to be performed by the second UE (102). 20. The network node of claim 19, wherein the network node is further configured to perform the method of any one of claims 10-13.