Transmit power management

Abstract

A user equipment (UE) receives, from a network node, a configuration including a maximum sensitivity degradation (MSD) limit per serving cell. The UE determines whether any uplink transmissions overlap any downlink receptions in physical resource blocks (PRBs) of the UE, leading to self-interference. The UE determines an MSD for the respective downlink PRBs in the event that UL transmissions are determined to overlap downlink receptions leading to self-interference. The UE determines, if required, a transmit power reduction to apply on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell. The transmit power reduction may be applied per PRB. The configuration may identify which uplink channel to apply the transmit power reduction to, including PUCCH, PUSCH, or uplink SRS. The configuration may identify which downlink channel to protect, including PDCCH, PDCCH search space, SSB, PDSCH, CSI-RS, or PRS.

Description

Field Example embodiments may relate to systems, methods and / or computer programs for transmit power management and control in mobile communication systems and the like. Background User devices, such as user equipment (UEs), that form part of a mobile communication system include transmitter and receiver modules. In some example embodiments, transmission and reception may be carried out at the same time leading to the potential for self-interference. Summary The scope of protection sought for various embodiments of the invention is set out by the independent claims. The embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the invention. In a first aspect, this specification describes an apparatus (such as a user device (e.g. a user equipment) of a mobile communication system) comprising: means for receiving, from a network entity, a configuration for the apparatus, said configuration including a maximum sensitivity degradation, MSD, limit per serving cell; means for determining whether any uplink transmission overlaps any downlink reception in physical resource blocks, PRBs, of the apparatus thereby leading to self-interference; means for determining an MSD value for the respective downlink PRBs in the event that uplink transmissions are determined to overlap downlink receptions leading to self-interference; and means for determining, if required, a transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell. In this way, Maximum Power Reduction (MPR) associated with MSD may be applied. The said configuration may be a carrier aggregation configuration. In some example embodiments, the apparatus further comprises means for applying the determined transmit power reduction. The said transmit power reduction may be applied on a per physical resource block, PRB, basis. In some example embodiments, the apparatus further comprises: means for reporting, to the network entity, a capability of the apparatus to apply said transmit power reduction. For example, the apparatus may report, to the network entity, a capability for apply Maximum Power Reduction (MPR) associated with MSD. The MSD value for the respective downlink PRBs may be determined based, at least in part, on measurements of self-interference (e.g. measurements at the apparatus / user device). The MSD values for the respective downlink PRBs may be determined based, at least in part, on data stored in one or more look-up tables. In some example embodiments, the apparatus further comprises: means for determining one or more MSD types relevant to said configuration. For example, the means for determining said MSD value comprises means for determining MSD contributions for each of said one or more MSD types. The said uplink transmissions may include product(s) thereof (such as harmonic products). In some example embodiments, the apparatus further comprises: means for registering the apparatus with the network entity, wherein said means for registering the apparatus includes said means for reporting the capability of the apparatus to apply transmit power reduction based on MSD. The means for registering the apparatus may comprise means for exchanging band combinations supported by the apparatus with the network node. In some example embodiments, the transmit power reduction is applied equally to each of a plurality of uplink PRBs. In some example embodiments, the transmit power reduction is applied differently to each of a plurality of uplink PRBs. In some example embodiments, the apparatus further comprises: means for receiving an indication from the network node indicating whether transmit power reduction is enabled. In some example embodiments, the configuration identifies one or more uplink channels to which said transmit power reduction is to be applied including at least one of PUCCH, PUSCH, or uplink SRS. In some example embodiments, the configuration identifies downlink channels to be protected, said channels including at least one of: PDCCH, PDCCH search space, SSB, PDSCH, CSI-RS or PRS. In a second aspect, this specification describes a method comprising: receiving, from a network entity, a configuration for a device, said configuration including a maximum sensitivity degradation, MSD, limit per serving cell; determining whether any uplink transmission overlaps any downlink reception in physical resource blocks, PRBs, of the device thereby leading to self-interference; determining an MSD value for the respective downlink PRBs In the event that uplink transmissions are determined to overlap downlink receptions leading to self-interference; and determining, if required, a transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell. The method may be implemented at a user device (e.g. a user equipment) of a mobile communication system. The method may comprise applying the determined transmit power reduction. The said transmit power reduction may be applied on a per physical resource block, PRB, basis. The method may comprise reporting, to the network entity, a capability of the device to apply said transmit power reduction. For example, the device may report, to the network entity, a capability for apply Maximum Power Reduction (MPR) associated with MSD. The MSD value for the respective downlink PRBs may be determined based, at least in part, on measurements of self-interference (e.g. measurements at the apparatus / user device). The MSD values for the respective downlink PRBs may be determined based, at least in part, on data stored in one or more look-up tables. The method may comprise determining one or more MSD types relevant to said configuration (e.g. by determining MSD contributions for each of said one or more MSD types). The said uplink transmissions may include product(s) thereof (such as harmonic products). The method may comprise registering the device with the network entity, wherein registering the device may include reporting the capability of the apparatus to apply transmit power reduction based on MSD. Registering the device may include exchanging band combinations supported by the apparatus with the network node. In some example embodiments, the transmit power reduction Is applied equally to each of a plurality of uplink PRBs. In some example embodiments, the transmit power reduction is applied differently to each of a plurality of uplink PRBs. The method may comprise receiving an indication from the network node indicating whether transmit power reduction is enabled. In some example embodiments, the configuration identifies one or more uplink channels to which said transmit power reduction is to be applied including at least one of PUCCH, PUSCH, or uplink SRS. In some example embodiments, the configuration identifies downlink channels to be protected, said channels including at least one of: PDCCH, PDCCH search space, SSB, PDSCH, CSI-RS or PRS. In a third aspect, this specification describes computer-readable instructions which, when executed by a computing apparatus, cause the computing apparatus to perform (at least) any method as described herein (including the method of the second aspect described above). In a fourth aspect, this specification describes a computer-readable medium (such as a non-transitory computer-readable medium) comprising program instructions stored thereon for performing (at least) any method as described herein (including the method of the second aspect described above). In a fifth aspect, this specification describes an apparatus comprising: at least one processor; and at least one memory Including computer program code which, when executed by the at least one processor, causes the apparatus to perform (at least) any method as described herein (including the method of the second aspect described above). In a sixth aspect, this specification describes a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to: receive, from a network entity, a configuration for a device, said configuration including a maximum sensitivity degradation, MSD, limit per serving cell; determine whether any uplink transmission overlaps any downlink reception in physical resource blocks, PRBs, of the device thereby leading to self-interference; determine an MSD value for the respective downlink PRBs in the event that uplink transmissions are determined to overlap downlink receptions leading to self-interference; and determine, if required, a transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell. In a seventh aspect, this specification describes: an input (or some other means) for receiving, from a network entity, a configuration for a device, said configuration including a maximum sensitivity degradation, MSD, limit per serving cell; a first control module (or some other means) for determining whether any uplink transmission overlaps any downlink reception in physical resource blocks, PRBs, of the device thereby leading to self-interference; a second control module for determining an MSD value for the respective downlink PRBs in the event that uplink transmissions are determined to overlap downlink receptions leading to self-interference; and a third control module (or some other means) for determining, if required, a transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell. Note that a single control module or processor may implement the features of two or more of the first, second and third control modules described above. In an eighth aspect, this specification describes an apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the processor, causes the apparatus to perform (at least) any method as described herein, including: receiving, from a network entity, a configuration fora device, said configuration including a maximum sensitivity degradation, MSD, limit per serving cell; determining whether any uplink transmission overlaps any downlink reception in physical resource blocks, PRBs, of the device thereby leading to self-interference; determining an MSD value for the respective downlink PRBs in the event that uplink transmissions are determined to overlap downlink receptions leading to self-interference; and determining, if required, a transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell. Brief Description of the Drawings Example embodiments will now be described by way of non-limiting example, with reference to the accompanying drawings, in which: FIG. 1 is a block diagram showing aspects of an example user equipment (UE) in accordance with an example embodiment; FIG. 2 is a block diagram showing output power in accordance with an example embodiment; FIG. 3 is a block diagram showing input power in accordance with an example embodiment; FIG. 4 is a plot demonstrating examples of interference in accordance with an example embodiment; FIG. 5 is a block diagram showing input and output powers in accordance with an example embodiment; FIG. 6 is a flowchart showing a method in accordance with an example embodiment; FIGS. 7 to 9 are message flow sequence showing algorithms in accordance with example embodiments; FIG. 10 is a flowchart showing a method in accordance with an example embodiment; FIG. 11 is a flowchart showing a method in accordance with an example embodiment; FIG. 12 is a schematic diagram of components of one or more of the example embodiments described previously; and FIG. 13 shows tangible media for storing computer-readable code which when run by a computer may perform methods according to example embodiments described herein. Detailed Description In the description and drawings, like reference numerals refer to like elements throughout. FIG. 1 is a block diagram showing aspects of an example user equipment (UE), indicated generally by the reference numeral 10, in accordance with an example embodiment. The UE 10 has multiple antennae, each operating within a different frequency band (specifically at 600MHz-lGHz, 1.7-2.1GHz, 2.3-2.8GHz and 3-5GHz respectively in this example). When the UE 10 is operating with more than one transceiver active at different spectrum allocations (e.g. as part of carrier aggregation or dual connectivity), the UE radio hardware is potentially subject to self-interference. Self-interference occurs, for example, when a UE transmitter has spectrum content, harmonic responses, or harmonic products that create interference inside an active receive band of the same UE. The system 10 demonstrates, in highly schematic form, self-interference due to antenna coupling and self-interference within front-end amplifiers. FIG. 2 is a block diagram showing output power, indicated generally by the reference numeral 20, in accordance with an example embodiment. FIG. 3 is a block diagram showing input power, indicated generally by the reference numeral 30, in accordance with an example embodiment. The block diagram 20 relates to transmit power of a device (such as the UE 10). Similarly, the block diagram 30 relates to received power of a device (such as the UE 10). The block diagram 20 shows two different maximum power levels. A first, higher, maximum power level 22 is a maximum power level that can be delivered by the device, for example in accordance with a relevant standard (e.g. 3GPP; thus the first maximum power level 22 may be referred to as 3GPP Pmax). A second, lower, maximum power level 24 is the maximum output power that the respective device can deliver in accordance with the principles described herein. The second maximum power level 24 is lower than the first maximum power level by an amount based on a maximum sensitivity degradation (MSD) of the device (as discussed in detail below). The second maximum power level 24 may be referred to as Pmax. The block diagram 20 shows a power range 26, which is an operational power range of the device. That power range is capped at the second maximum power level 24 (Pmax). The block diagram 30 include a power range 32 of the receiver of the device. A portion 34 of the receiver power relates to the MSD value, which defines an allowed relaxation of a reference sensitivity of the receiver due to self-interference as a result of transmissions of the device (e.g. in carrier aggregation or dual connectivity configurations). An uplink (TX) signal that causes the presence of the interference in the receive band is called the "aggressor" and can be either one or two band uplink combinations (as discussed in detail above). The receive band of the UE where the product of the TX aggressor(s) end up is called the RX victim band. Thus, a UE (such as the UE 10) can have both an aggressor role and a victim role in relation to self-interference. Maximum sensitivity degradation (MSD) refers to the specified allowed sensitivity degradation a UE is allowed to have In DL bands in CA / DC band combinations, where UE self-interference from uplink falls into a DL band. An MSD value is the level of relaxation the UE requires to be compliant with the normal reference sensitivity requirements. The relaxation may be required since the TX aggressor(s) may cause an interference level increase matching the MSD value. The specified MSD value Is typically a static value per band combination, hence a network node (e.g. a gNB) generally assumes that this value is always present, and if this CA configuration is used, the gNB will have to adapt its DL transmissions according to this MSD value (e.g. by reducing MCS, Increasing power, avoiding that the UE will have to make a UL transmission while simultaneously receiving in DL, or completely avoiding to utilize this CA configuration etc.). The static MSD value may represent a worst-case scenario and, as such, operating according to this static value may result in inefficient operation. Note that there Is not necessarily a 1:1 relation between the output power level of the TX aggressor that causes self-interference to degrade the reference sensitivity and the MSD value of the RX victim band that relaxes the requirement to the reference sensitivity. The relation depends, for example, on the MSD type (as discussed further below). There are different types of sources in the UE that lead to self-interference, but they may be regarded as belonging to two different groups. The first group (where only one uplink (UL) component carrier is used in a band combination) includes uplink harmonics harmonic mixing and cross-band distortion (see Table 1 below). The second relates to inter-modulation distortion, where more than one UL component carrier is used (see Table 2 below). MSD Type Relation UL Harmonic UL2 / DL1 UL3 / DL1 UL4 / DL1 UL5 / DL1 Harmonic mixing UL1 / DL2 UL1 / DL3 UL1 / DL4 UL1 / DL5 UL2 / DL3 UL3 / DL4 UL4 / DL3 Cross band UL1 / DL1 Table 1: Self-interference caused by uplink harmonics, harmonic mixing, or cross band distortion By way of example, UL2 / DL1 in table 1 below means the second harmonic (2) of the uplink can match the fundamental (1) of the downlink. MSD Type Relation IMD2 UL1A-UL1B UL1B-UL1A UL1A+UL1B IMD3 UL2A-UL1B UL2B-UL1A UL2A+UL1B UL2B+UL1A IMD4 3A / B-1A / B, 3A / B+1A / B, 2A / B-2A / B, 2A / B+2A / B combinations IMD5 3A / B-2A / B, 3A / B+2A / B, 4A / B-1A / B, 4A / B+1A / B Table 2: Self-interference cause by inter-modulation distortion (IMD). Uplink (UL) harmonics (see Table 1) may cause self-interference in the other downlink (DL) component carrier as a result of one or more harmonics of the uplink falling inside the other DL component carrier bandwidth. Harmonic mixing (see Table 1) may cause self-interference when a combination of the UL harmonics coincides with the DL harmonic of the other DL component. Cross band distortion (see Table 1) is an expression of self-interference when the output spectrum of the UL component carrier falls inside the DL component carrier bandwidth. This can be considered as adjacent channel leakage of the transmitter, where the leakage depends on the non-linear behavior of the power amplifier. Inter-modulation distortion (IMD) (see Table 2) occurs when two UL component carriers inter-modulate (mix) and the product of the mixing of the UL component carriers fall inside the receiver band of one or the other DL component carrier bandwidth at the fundamental carrier frequency of the downlink band. Special cases of IMD (noncontiguous ULCA and triple beat) belong in this category as well. Some of the MSD types have an uplink / downlink relation of IdB to IdB, which means that IdB increase in TX output power of the UE results in a IdB increase in the selfinterference level, which degrades the UE sensitivity by IdB. In other MSD types, this relationship follows the order of the product that generates the self-interference, as the example case of second harmonic of the TX falling inside the RX victim band will have a relation of IdB to 2dB, which means that IdB increase of TX output power results in 2dB increase to the power level of the second harmonic (so that the sensitivity of the RX victim receive band reduces by 2dB for every IdB increase in TX output power). FIG. 4 is a plot, indicated generally by the reference numeral 40, demonstrating examples of interference in accordance with an example embodiment. The plot 40 shows a particular carrier aggregation configuration where the x-axis is the n78 TDD channel allocation for UL and DL respectively and the y-axis is the n3 FDD channel allocation for UL. As shown in the plot 40, combining an uplink frequency of n3 with a downlink operation in n78 the range from ~3.42GHz to ~3.54GHz may result in the n3 uplink second harmonic response affecting the downlink quality of n78 inside the UE through selfinterference. However, other frequencies do not result in self-interference. A UE typically contains a table that links self-interference affected band combinations with and MSD value along with type of MSD case, and the order of the product that causes the interference. It cannot be excluded that an advanced UE can have a method to derive an MSD value. FIG. 5 is a block diagram, indicated generally by the reference numeral 50, showing input and output powers in accordance with an example embodiment. The block diagram 50 shows a relation of the UE memory (tables of CA etc.) and method mapping the content onto the TX aggressor and RX victim band. If the MSD value is, for example, 21dB for a third order uplink harmonic that falls inside the RX victim band, the type and order also determines the output power level of the TX aggressor at which no self-interference is present. When the UE output power is relaxed by 1 dB from the maximum output power level, the level of the aggressor reduces the self-interference by 3dB, meaning that in case the MSD value is 21dB a reduction of the output power by 7dB would not cause any self-interference. This Is shown at the right in FIG. 5 as the UE output power SI (self-interference) that equals or matches the MSD value divided by the order of the MSD type. This relation means that whenever the MSD value is known, the self-interference "free" output power range is known, as well as the top output power range in which the UE will suffer from self-interference (as indicated in FIG. 5 with a marking). FIG. 6 is a flowchart showing a method, indicated generally by the reference numeral 60, in accordance with an example embodiment. The method 60 may be implemented using an algorithm. The method 60 starts with a registration phase 62 where a UE registers with a network. During registration, band-combinations supported by the UE are exchanged with the network and a list of updated MSD values (if the UE can perform better MSD than that specified in specification) may be provided to the network, which allows the network node (gNB) to predict what MSD performance the UE will have In its own supported band combination. As discussed further below, in the registration phase 62, the UE can report that it has the capability to apply an uplink transmit power reduction to keep the self-interference level at a level which implies an MSD which is below a MSD limit. This may also be referred to as Maximum Power Reduction (MPR) associated with MSD (or MSD MPR). The method 60 then moves to a configuration phase 64 where the UE is configured for carrier aggregation, including, for example, cross-carrier signalling and Physical Uplink Control Channel (PUCCH) groups, Physical Uplink Shared Channel (PUSCH), Physical Downlink Shared Channel (PDSCH) and Physical Downlink Control Channel (PDCCH) search spaces. The relevant MSD limit per serving cell can be signalled to the UE as part of the configuration phase 64 (for example in an RRC IE ServingCellConfig for the serving cell). Next, an execution phase 66 is implemented. In the execution phase, when the UE detects that there is time overlapping uplink transmission and downlink reception that is also subject to MSD, the UE will determine that it should apply the uplink transmit power reduction (the MSD MPR(as discussed in detail below)) and derive the MSD MPR that the UE will apply on the uplink transmission(s) causing the MSD. Thus, the method 60 provides a mechanism enables the UE able to determine which UL physical resource blocks (PRBs) will cause which DL PRBs to be affected by MSD (if any). The UE also determines the MSD value that these DL PRBs will suffer. The UE evaluates the need for action and if needed, takes action by means of enforcing a transmit power reduction (e.g. a new variant of MPR) in order to keep the MSD below a specified sensitivity relaxation threshold (i.e., the MSD limit). The UE signals the gNB that it supports this capability (as part of the registration phase 62), allowing the gNB to signal the tolerated sensitivity relaxation threshold for the MSD to the UE (as part of the configuration phase 64). More specifically, when the UE has determined the MSD impact on an allocated set of DL PRBs overlapping in time with an allocated UL PRBs, the UE can apply the MPR variant described herein so that the MSD is kept below the signalled MSD limit. FIG. 7 is a message flow sequence, Indicated generally by the reference numeral 70, showing an algorithm in accordance with an example embodiment. The algorithm 70 shows messages transferred between a UE 72, a PCell node 74 and an SCell node 76 (the PCell and SCell nodes forming part of a network node). The algorithm 70 is an example implementation of the registration phase 62 of the method 60 described above. As discussed above, in the operation 62, the UE provides information such as bandcombinations supported by the UE to the network node (specifically the PCell node 74). As shown in FIG. 7, the UE 72 sends a message 78 to the PCell node 74 indicating whether the UE has the capability to mitigate MSD (e.g. whether MPR associated with MSD (or some similar transmit power reduction method) is supported by the UE). FIG. 8 is a message flow sequence, indicated generally by the reference numeral 80, showing an algorithm in accordance with an example embodiment. The algorithm 80 shows messages transferred between the UE 72, the PCell node 74 and the SCell node 76. The algorithm 80 is an example implementation of the configuration phase 64 of the method 60 described above. As discussed above, in the configuration phase 64, the UE is configured for carrier aggregation. As shown in FIG. 8, in the example algorithm 80, the relevant MSD limit (e.g. MSD limit per serving cell) is generated at the PCell in operation 82 and provided to the UE 72 in message 84. FIG. 9 is a message flow sequence, indicated generally by the reference numeral 90, showing an algorithm in accordance with an example embodiment. The algorithm 90 shows messages transferred between the UE 72, the PCell node 74 and the SCell node 76. The algorithm 90 is an example Implementation of the execution phase 66 of the method 60 described above. As shown in FIG. 9, in the example algorithm 90, the UE 72 determines the MSD impact from UL to DL allocation (operation 92), and initiates action (if necessary) to keep the MSD below the signalled MSD limit (operation 94). FIG. 10 is a flowchart showing a method, indicated generally by the reference numeral 100, in accordance with an example embodiment. The method 100 may be implemented using an algorithm. The method 100 may be implemented at a device (e.g. a user device, such as the UE 72 described above). The method 100 starts at operation 101, where the device reports, to a network entity (e.g. a gNB), a capability of the device to apply maximum power reduction (MPR), or some similar algorithm, associated with MSD. The MPR. may be applied on uplink physical resource block(s), PRB(s), causing the self-interference. The operation 101 may be implemented as part of a registration step (such as the registration operation 62 of the method 60 described above). At operation 102, the device receives a maximum sensitivity degradation (MSD) limit from the network entity. The MSD limit may be per serving cell. The MSD limit may be received as part of the configuration operation 64 described above. At operation 103, self-interference is identified. Specifically, the device determines whether any uplink transmissions (e.g., product of the TX aggressor(s)) overlap any downlink receptions (e.g. downlink physical resource blocks of the device). At operation 104, an MSD value (e.g. for the respective downlink PRBs) is determined in the event that uplink transmissions are determined to overlap downlink receptions leading to self-interference. Operation 104 may include determining one or more MSD types relevant to said configuration. For example, determining said MSD value comprises means for determining MSD contributions for each of said one or more MSD types. At operation 105, a transmit power reduction is determined (If required), the transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell. As discussed above, the transmit power reduction, when implemented, may Implement Maximum Power Reduction, MPR, associated with MSD. Finally, at operation 106, the determined transmit power reduction is applied. FIG. 11 is a flowchart showing a method, indicated generally by the reference numeral 110, in accordance with an example embodiment. The method 110 may be implemented using an algorithm. The method 110 has many similarities with the method 100 described above and may be implemented at a device, such as the UE 72 described above. At step 1 of the method 110, the UE reports its MSD MPR capability to the network. This can be done in the UE capability exchange procedure where also the UE will report Its MSD values per frequency band combination (if it can perform better than the MSD values specified in specifications). At step 2 of the method 110, the network configures the UE with a MSDlimit which the UE can use to determine when to apply MSD MPR (see step 7 below). In steps 3 to 5 of the method 110, the UE Is configured with a CA configuration, and the UE gets scheduled (for UL and / or DL allocations) on its serving cells. The UE then checks if the allocations will cause MSD, by first Identifying whether there Is an RX and TX event overlapping in time (step 5). In step 6 of the method 110, the UE checks whether there is MSD mapping from the UL allocation towards the DL allocation by following for example the equations (7.3) to (7.6) discussed in detail below. In step 7 of the method 110, the UE calculates the MSD MPR value (MPRmsd) that it would apply (see the equation 7.13 discussed below) which includes the MSD that will be caused by the UL allocation and with the non-MSD-MPR applied transmit power. In step 8 of the method 110, if MPR MSD is determined to be non-zero, then it is applied in step 9 (otherwise step 9 is omitted). The method then returns to step 4. The method and algorithms described above may be implemented in a number of ways. Some example implementation details are provided below. The skilled person will, however, be aware of a number of variants that could be implemented. Some details of example implementations are discussed below. Applying the MSD Maximum Power Reduction (MPR) (MPR.msb) For total UE uplink power: = — PL + A — — (7. If where: • Pcmax is the UE configured maximum output power. • Po is a pre-configured received power target assuming full pathloss compensation. • a between 0 and 1 is the fractional power control factor. o a = 0 means no pathloss compensation, i.e. all UEs transmit at the same power o a = l means full pathloss compensation, which tries to achieve same received power for all UEs • A is a closed loop power control component which allows base station to adjust the transmit power at UE. This is based on Transmit Power Control (TPC) command from Downlink Control Information (DCI) on the PDCCH. • "MPRmsd" is conditioned by UE calculations of an overlap (MSD case) and derived as a function of the impact of the affected PRBs Similar for PUSCH, details found at: . , ..: + f 3“ • s,.; ij) ■ r . s p + , s,(0 + £ ,,(£, i) - " j=0: MSG3 in random access, or PUSCH when O-PUSCH-AlphaSet is not provided. j=l: Configured grant. j=2 to 31: Dynamic grant It should be noted that MPR MSD can be applied similarly to all variants of uplink transmit power equations, for example for Sounding Reference Signal (SRS) and Physical Random Access Channel (PRACH). In an alternative implementation, the MPRmsd is not specified in power control mechanism, but instead as a requirement as is also the case with existing MPR variants (P-MPR and A-MPR). Determining which UL physical resource block (PRBs) cause MSD to allocated DL PRBs It may be assumed either that the UE knows from its own specification which MSD types are present in particular CA configurations, or that it is known from 3GPP specifications. Alternatively, the UE could determine the MSD type using the equations set out below for UL harmonic, Harmonic mixing, cross band and IMD respectively (as discussed in detail below). In these equations a freqiow and a freqhigh are used and these low and high values indicate the channel / RB allocation maximum and minimum placement of the component carrier, and can be used for the channel bandwidth in frequency range checks and can be set based on the frequency band boundaries (to determine which MSD types are present using the CA configuration) or by specific PRBs when interested in which MSD Is Impacted knowing the precise PRB allocation, • UL x'th harmonic order: • Harmonic mixing: • Cross band: Here any suitable model can be considered. For example, a model where an ACLR order from 1 to 5 is considered as: (Z5) • IMD2: All combinations of first order harmonics of band A and B added or subtracted. We may denote this a IMD2-set and calculate it for A and B as with first order harmonics: • IMD3: All combinations that includes the 2nd order harmonics and 1st order harmonics of band A and B. If we denote this as an IMD3-set it should not include combinations from the IMD2-set. It can be calculated similarly as for IMD2, but for combinations UL2A-UL1B, UL2B-UL1A, UL2A+UL1B, UL2B+UL1A, where UL2x denotes a second order harmonic from band x. As this involved multiple calculations similar to IMD2, the low frequencies are again subject to a minimum function and the high is subject to a maximum function. • IMD4: Similar procedure as for IMD3, but now with even more combinations. • IMD5: Similar procedure as for IMD3, but now with even more combinations. Determining (e.g. at a UE) how much self-interference the UL transmission cause to the DL reception One example of how the MSD value can be calculated is to translate MSD from the value in the 3GPP specifications into an instantaneous value by the following expression: if MSB. otferwise where, o Bandwidth scaling relate to UE supported bandwidth combination set (BCS), it consists of a DL BW scaling relative to the specified value used for the MSD requirement used for the MSD specified value and can follow the equation: o UL transmit power scaling TXPscale is a reduction factor compared to the TX power considered for the MSDspec but also scales with the order implied in the MSD type o How much the MSD scales with the UL IX power depends on the MSD Type, and below is an example of a scaling parameter of how much MSD reduce when the UL TX power reduce by IdB: 3^B, / er.W33 ^rfs, fen-5^6, / ^- / ^35 1 dB, for 311 = 2dB, ;7,91 BdB.for UL3 4dB,for VIA SdB.forUH IdB,for ACLRl IdB.for ACLB2 o Note that harmonic mixing these are similar as to uplink harmonics (from the min order). o Note that for cross-band interference, this scaling parameter is provided as a ACLR order that reduces with lOdB per additional adjacent channel step. The ACLR values per order may scale as provided above (e.g. IdB for ACLR1 with TXP scaling by IdB, but that can be counteracted at the UE, so the numbers provided above should be considered examples). o This function also needs to account for the potential scaling that the UE is doing due to existing MPR scaling mechanisms and here denoted TXPmpr. o This function also needs to consider what is the determined UL TX power for the transmission that is determined to cause MSD. We could call that TXPUEactuai and could for example be determined following the power control expressions provided in TS 38.213. o And lastly the MSD scaling due to UL TX power can be: J (J A / ’ + i APjjo o Relative overlap takes care of the remnants from the BW scaling and results in a factor of MSD contribution remaining in the configuration: o And overlap can be determined by a simple check: . J - » 0 (7-12) Additionally, the UE is associated with a bandwidth class, uplink power classes in TDD bands and similar information the network may use to determine the impact of the scaling function parameters, like the UE supports only BCS 0 and not BCS 4&5 for a combination, then it may have less throughput than other combinations. In TDD a higher power class can make the use of the TDD band in uplink more attractive. The UE use this information to determine the MSD scaling. Now, that the UE has an estimate of the MSD that its current settings would be causing, this is used to determine whether the UE needs to apply an action to reduce the transmit power and hence the caused self-interference and can be determined simply by: = ma x 0)

[43] (7.1S) Handling the case of MSD caused by more than one UL transmission In the case where there is more than one UL transmission (as can be the case with UL CA), IMD products can occur which together form an MSD product. In this case, it might be so that the BW scaling and TXP scaling functions should be slightly changed compared to the functions provided in (7.10) and (7.11). The simplest implementation would be that the UE may set the BW scaling and TXP scaling functions following the UL transmission causing the highest order harmonic. In an alternative embodiment, the UE may deduct an average or weighted average of the BW scaling and TXP scaling functions of the UL transmissions causing the IMD product. The UE will then have to determine how to apply MSD MPR {mprmsb). Some example implementations are discussed below. In one embodiment, the UE will apply MSD MPR equally on all UL transmissions causing MSD. This has the benefit that it is simple to derive and specify. In another embodiment, the UE will apply MSD MPR proportionally to the IMD order, for example if one product is a second order harmonic, and the other is a third order harmonic, UE would apply a 2 / 3 MSD MPR on the UL transmission causing the second order harmonic, and 1 / 3 on the other UL transmission. This has the benefit that it will affect the UL transmission more than is causing more MSD which is the higher order. In yet another embodiment, the UE will be configured by the network, with a ratio of MSD MPR along with the UL CA configuration. For example, the gNB can configure a ratio of [1, 0] or alternatively [0.8, 0.2] for a PCell and SCell to make the UE apply MSD MPR only on the PCell or with a 80 / 20% split on PCell and SCell. This has the benefit that the gNB can force a bias to the MSD MPR on a cell that it might want to prioritize coverage for, even when it is causing MSD. A number of variants to the example embodiments are contemplated. Some specific configurations are described further below. How the UE determines how much MSD MPR it needs to apply (e.g. Equation (7.13)). This includes allowing the UE to determine MPR MSD, based not on the specified bandwidths In TS 38.101-1 (typically 5MHz, 10MHz), but in any granularity (as for example (7.7). MSD action by MPR determined by UE self-measurements The UE may have the capability to measure the MSD that its uplink is causing to the downlink band and using that to determine the MSD action in order to meet the MSD limit signalled by the network. UE self-measurements may require a specific reference signal pattern in order to be detectable at the receiver side. That also means that equations (7.7) can still be needed in order to estimate the MSD impact a future allocation will have. For example, the UE may replace MSD^ with a MSDmeasured, TXPUEMSDspec with TXPUEMSDmeasured , BWMSDspec with B^MSDmeasuredr ^MSD^req^igh With dlMSDmeasured,freq^ig^ and dl^sD,freqiow With dlMsDmeasured.freqtow from its own measurement of MSD, and then formulate the bandwidth scaling and TXP scaling relative to the MSD measurement instead of the MSD specification procedure and it can be formulated as below: srai® J •• ^scsle '’“f’stxsie W4-*tai' LJ ^'■■syed.s^..-, s. JSSLw.^..: — , h.lf crosj^^otftervrss* For the case of more than one UL transmission, the UE could do the measurement with more than one UL transmission occurring at the same time. This in turn brings different MPR according to the component carrier of the individual bands. Look up table (LUT) as a method for determining MSD presence In this embodiment the UE may indicate that it only has the capability to determine the MSD MPR based on 3GPP specification to determine whether a DL band is impacted by MSD rather than relying on the mapping equations in (7.3) to (7.6). This may be done based on a band combination basis and can also be by sub-band resolution. In this way, the procedure at the UE is simplified, but also means that the UE will need to resort to the closest LUT entity to determine whether MSD is present or not. MSD based MPR Is applied with all DL and UL transmission Expanding on the method 110 described above with reference to FIG. 11, step 4 of the method may be expanded to also consider for example in uplink; SRS, PUCCH, configured grants, and for example in downlink consider Synchronization Signal Block (SSB), Channel State Information Reference Signal (CSI-RS), Positioning Reference Signal (PRS), Physical Downlink Control Channel (PDCCH) search spaces. In a further embodiment, the MSD MPR can be configured to be applied for each of these types individually, for example by the downlink reception type such that a parameter for each type can be configured, e.g. to enable MSD MPR for SSB receptions and so on. MSD based MPR reported in power headroom report In this embodiment, the UE reports the MPR applied, which can allow the network to become aware of how much MSD based MPR the UE is actually applying, and hence it can know how much more MSD MPR the UE can do before the MSD limit is exceeded. In one implementation, the UE reports the MPR value only as state-of-the-art reporting of e.g. FR2 P-MPR. In another implementation, the UE reports an average MPR value (i.e. when it is not applied for all UL PRBs allocated. In yet another implementation, the UE will compute the PHR directly including the MPR value, meaning that the UE will subtract the MPR value applied from its maximum transmit power. Replacing MSD limit with an SINR limit as input to the MSD action In an alternative implementation to the interference aware MSD action, the MSD limit is replaced with a signal-to-noise-and-interference-and-self-interference (SINMR) limit. That is, the UE is configured to measure e.g. RSRP or Ll-SINR (TS38.215) at a time instance where the UE is not simultaneously transmitting and receiving (no selfinterference should be present) and then the UE estimates the MSD impact e.g. by equation (7.7) which is then subtracted (logarithmically) from the SINR value. The UE will then use SINMRiimU: instead of MSDUmlt in (7.13). In another embodiment, the UE has self-interference measurement capabilities, and in that case, the UE will not estimate the MSD, but apply the measured MSD instead. This embodiment therefore assumes that the UE has methods for a UE to distinguish interference and self-interference. In another embodiment, the SINR limit is signalled as a function which depends on the MCS of the DL allocation impacted by MSD. In yet another embodiment, the UE will only activate the MSD action, if the SINR is below a threshold, i.e. such that the UE is not starting to apply MSD actions if the main source of interference is not the selfinterference. gNB dynamically indicating whether the UE should enforce MSD MPR By enforcing the UE to apply MPR on the UL PRBs that impacts some or all of the DL PRBs with self-interference, the gNB is also implicitly giving a weight or priority between UL coverage and DL throughput. As this priority can change over time, e.g. with the buffer size or traffic flow priority in the specific allocation, the gNB could want to be able to dynamically change MSD limit or even disable MSD MPR. To be able to do so, a fast mechanism to do so could be beneficial. The MSD limit may be signalled for example via RRC or MAC CE, which compared to RRC level signalling, would allow for a much faster and lightweight signalling overhead at the cost of less flexibility. In another variant the MSD limit is signalled via a DCI carried over PDCCH allowing even faster changes and lightweight changes (but also causes signalling overhead in the DCI when not needed). In yet another variant, the MSD MPR is enabled / disabled via a bit in a DCI carried over PDCCH. For completeness, FIG. 12 is a schematic diagram of components of one or more of the example embodiments described previously, which hereafter are referred to generically as a processing system 300. The processing system 300 may, for example, be the apparatus referred to in the claims below. The processing system 300 may have a processor 302, a memory 304 coupled to the processor and comprised of a RAM 314 and a ROM 312, and, optionally, a user input 310 and a display 318. The processing system 300 may comprise one or more network / apparatus interfaces 308 for connection to a network / apparatus, e.g. a modem which may be wired or wireless. The network / apparatus interface 308 may also operate as a connection to other apparatus such as device / apparatus which is not network side apparatus. Thus, direct connection between devices / apparatus without network participation is possible. The processor 302 is connected to each of the other components in order to control operation thereof. The memory 304 may comprise a non-volatile memory, such as a hard disk drive (HDD) or a solid state drive (SSD). The ROM 312 of the memory 304 stores, amongst other things, an operating system 315 and may store instructions, such as for example, software applications 316. The RAM 314 of the memory 304 is used by the processor 302 for the temporary storage of data. The operating system 315 may contain instructions or code which, when executed by the processor implements aspects of the method, algorithms and sequences 60, 70, 80, 90, 100 and 110 described above. Note that in the case of small device / apparatus the memory can be most suitable for small size usage i.e. not always a hard disk drive (HDD) or a solid state drive (SSD) is used. The processor 302 may take any suitable form. For instance, it may be a microcontroller, a plurality of microcontrollers, a processor, or a plurality of processors. The processing system 300 may be a standalone computer, a server, a console, or a network thereof. The processing system 300 and needed structural parts may be all inside device / apparatus such as loT device / apparatus i.e. embedded to very small size. In some example embodiments, the processing system 300 may also be associated with external software applications. These may be applications stored on a remote server device / apparatus and may run partly or exclusively on the remote server device / apparatus. These applications may be termed cloud-hosted applications. The processing system 300 may be in communication with the remote server device / apparatus In order to utilize the software application stored there. FIG. 13 shows a tangible media, in the form of a removable memory unit 365, storing computer-readable code which when run by a computer may perform methods according to example embodiments described above. The removable memory unit 365 may be a memory stick, e.g. a USB memory stick, having internal memory 366 storing the computer-readable code. The internal memory 366 may be accessed by a computer system via a connector 367. Of course, other forms of tangible storage media may be used, as will be readily apparent to those of ordinary skilled in the art. Tangible media can be any device / apparatus capable of storing data / information which data / informatlon can be exchanged between devices / apparatus / network. Embodiments of the present invention may be implemented In software, hardware, application logic or a combination of software, hardware and application logic. The software, application logic and / or hardware may reside on memory, or any computer media. In an example embodiment, the application logic, software or an instruction set is maintained on any one of various conventional computer-readable media. In the context of this document, a "memory" or "computer-readable medium" may be any non-transitory media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer. Reference to, where relevant, "computer-readable medium", "computer program product", "tangibly embodied computer program" etc., or a "processor" or "processing circuitry" etc. should be understood to encompass not only computers having differing architectures such as single / multi-processor architectures and sequencers / parallel architectures, but also specialised circuits such as field programmable gate arrays FPGA, application specify circuits ASIC, signal processing devices / apparatus and other devices / apparatus. References to computer program, instructions, code etc. should be understood to express software for a programmable processor firmware such as the programmable content of a hardware device / apparatus as instructions for a processor or configured or configuration settings for a fixed function device / apparatus, gate array, programmable logic device / apparatus, etc. The term "means" as used in the description and in the claims may refer to one or more individual elements configured to perform the corresponding recited functionality or functionalities, or it may refer to several elements that perform such functionality or functionalities. Furthermore, several functionalities recited in the claims may be performed by the same individual means or the same combination of means. For example, performing such functionality or functionalities may be caused in an apparatus by a processor that executes instructions stored in a memory of the apparatus. If desired, the different functions discussed herein may be performed in a different order and / or concurrently with each other. Furthermore, if desired, one or more of the abovedescribed functions may be optional or may be combined. Similarly, it will also be appreciated that the flow diagrams and sequences of Figures 6 to 11 are examples only and that various operations depicted therein may be omitted, reordered and / or combined. It will be appreciated that the above-described example embodiments are purely illustrative and are not limiting on the scope of the invention. Other variations and modifications will be apparent to persons skilled in the art upon reading the present specification. Moreover, the disclosure of the present application should be understood to include any novel features or any novel combination of features either explicitly or implicitly disclosed herein or any generalization thereof and during the prosecution of the present application or of any application derived therefrom, new claims may be formulated to cover any such features and / or combination of such features. Although various aspects of the invention are set out in the independent claims, other aspects of the invention comprise other combinations of features from the described example embodiments and / or the dependent claims with the features of the independent claims, and not solely the combinations explicitly set out in the claims. It is also noted herein that while the above describes various examples, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope of the present invention as defined in the appended claims.

Claims

1. An apparatus comprising:means for receiving, from a network entity, a configuration for the apparatus, said configuration including a maximum sensitivity degradation, MSD, limit per serving cell;means for determining whether any uplink transmission overlaps any downlink reception in physical resource blocks, PRBs, of the apparatus thereby leading to selfinterference;means for determining an MSD value for the respective downlink PRBs in the event that uplink transmissions are determined to overlap downlink receptions leading to self-interference; andmeans for determining, if required, a transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell.

2. An apparatus as claimed in claim 1, further comprising:means for applying the determined transmit power reduction.

3. An apparatus as claimed in claim 2, wherein said transmit power reduction is applied on a per physical resource block, PRB, basis.

4. An apparatus as claimed in any of claims 1 to 3, further comprising:means for reporting, to the network entity, a capability of the apparatus to apply said transmit power reduction.

5. An apparatus as claimed in any one of the preceding claims, further comprising: means for determining one or more MSD types relevant to said configuration.

6. An apparatus as claimed in claim 5, when dependent on claim 4, wherein the means for determining said MSD value comprises means for determining MSD contributions for each of said one or more MSD types.

7. An apparatus as claimed in any one of the preceding claims, wherein the MSD values for the respective downlink PRBs are determined based, at least in part, on self-interference caused by said uplink transmissions, as determined by said apparatus.

8. An apparatus as claimed in any one of the preceding claims, wherein the MSDvalues for the respective downlink PRBs are determined based, at least in part, on data stored in one or more look-up tables,9. An apparatus as claimed in any one of the preceding claims, wherein said uplink transmissions include harmonic product(s) thereof.

10. An apparatus as claimed in any one of the preceding claims, further comprising: means for registering the apparatus with the network entity, wherein said means for registering the apparatus includes said means for reporting the capability of the apparatus to apply transmit power reduction based on MSD.

11. An apparatus as claimed in claim 10, wherein said means for registering the apparatus comprises means for exchanging band combinations supported by the apparatus with the network node.

12. An apparatus as claimed in any one of the preceding claims, wherein said transmit power reduction is applied equally to each of a plurality of uplink PRBs.

13. An apparatus as claimed in any one of claims 1 to 10, wherein said transmit power reduction is applied differently to each of a plurality of uplink PRBs.

14. An apparatus as claimed in any one of the preceding claims, further comprising: means for receiving an indication from the network node indicating whether transmit power reduction is enabled.

15. An apparatus as claimed in any one of the preceding claims, wherein the configuration identifies one or more uplink channels to which said transmit power reduction is to be applied including at least one of PUCCH, PUSCH, or uplink SRS.

16. An apparatus as claimed in any one of the preceding claims, wherein the configuration identifies downlink channels to be protected, said channels including at least one of: PDCCH, PDCCH search space, SSB, PDSCH, CSI-RS or PRS.

17. An apparatus as claimed in any one of the preceding claims, wherein said configuration is a carrier aggregation configuration.

18. A method comprising:receiving, from a network entity, a configuration for a device, said configurationincluding a maximum sensitivity degradation, MSD, limit per serving cell;determining whether any uplink transmission overlaps any downlink reception in physical resource blocks, PRBs, of the device thereby leading to self-interference;determining an MSD value for the respective downlink PRBs in the event that uplink transmissions are determined to overlap downlink receptions leading to selfinterference; anddetermining, if required, a transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell.

19. A computer program comprising instructions which, when executed by an apparatus, cause the apparatus to:receive, from a network entity, a configuration for a device, said configuration including a maximum sensitivity degradation, MSD, limit per serving cell;determine whether any uplink transmission overlaps any downlink reception in physical resource blocks, PRBs, of the device thereby leading to self-interference;determine an MSD value for the respective downlink PRBs in the event that uplink transmissions are determined to overlap downlink receptions leading to self-interference; anddetermine, if required, a transmit power reduction to be applied on uplink PRBs causing the effect of MSD for downlink PRBs in order to meet the MSD limit per serving cell.Application No: GB2406887.6Examiner:Contract Unit ExaminerClaims searched: 1-19Date of search: 27 January 2025Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance X Y X: 1-8, 10-19 Y: 9 WO2023 / 131108 Al (HUAWEI TECH CO LTD) abstract, table 2 E,& 1-8, 10- 14, 17-19 EP4451579Al (HUAWEI TECH CO LTD) paragraphs [0018], [0020], [0067], [0069], [0102], [0109], [0112], [0121], [0122], [0124] X,Y X; 1-8, 10-19 Y: 9 WO2022 / 260381 Al (LG ELECTRONICS INC) paragraphs [0182], [0195], [0196], [0267], [0290] 9 WO2023 / 150082 Al (APPLE INC) paragraphs [0059], [0067] - [0069] A - 3 GPP DRAFT, vol RAN WG4, 2022, VIVO, "Further discussion on MSD mitigation of FDD HPUE" URL: https: / / ftp.3gpp.org / tsg_ran / WG4_Radio / TSGR4_102-e / Docs / R4-2204938.zip the whole documentCategories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of same category. before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:Search of GB, EP, WO &US patent documents classified in the following areas of the UKCX :Worldwide search of patent documents classified in the following areas of the IPC_____________H03D; H04B; H04L; H04W______________________________________The following online and other databases have been used in the preparation of this search reportInternational Classification:Subclass Subgroup Valid From H04W 0052 / 24 01 / 01 / 2009 H04W 0052 / 14 01 / 01 / 2009

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