KOVACS ISTVAN Z (DK)
LAURIDSEN MADS (DK)
VIERING INGO (DE)
EP1244228A2 | 2002-09-25 | |||
US6763006B1 | 2004-07-13 |
CLAIMS 1. An apparatus comprising: at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: determine at least one power setting adjustment for at least one terminal based on at least one gain setting adjustment for a satellite; and provide the least one power setting adjustment for the at least one terminal to the at least one terminal. 2. The apparatus of claim 1, wherein the determining the at least one power setting adjustment for the at least one terminal based on the at least one gain setting is based on information received from the satellite. 3. The apparatus of any of claims 1 and 2, wherein the at least one gain setting adjustment for the satellite comprises at least one uplink gain setting adjustment for the satellite, at least one downlink gain setting adjustment for the satellite and/or at least one difference between an uplink gain setting adjustment for the satellite and a downlink gain setting adjustment for the satellite. 4. The apparatus of claim 3, wherein the at least one uplink gain setting adjustment for the satellite comprises at least one of an uplink reception gain setting adjustment on an access link or an uplink transmission gain setting adjustment on a feeder link; or wherein the at least one downlink gain setting adjustment for the satellite comprises at least one of an downlink reception gain setting adjustment on a feeder link or a downlink transmission gain setting adjustment on an access link. 5. The apparatus of any of claims 1 to 4, wherein the at least one power setting adjustment for the at least one terminal comprises at least one uplink power setting adjustment. 6. The apparatus of any of claims 1 to 5, wherein the at least one power setting adjustment for the at least one terminal is provided to the at least one terminal via at least one broadcast signal or at least one dedicated signal. 7. The apparatus of any of claims 1 to 6, wherein the at least one power setting adjustment for the at least one terminal is specific for a terminal or generic for a plurality of terminals. 8. The apparatus of any of claims 1 to 7, wherein the at least one power setting adjustment for the at least one terminal is specific for a channel or a reference signal or generic for a plurality of channels and/or a plurality of reference signals. 9. The apparatus of claim 8, wherein the at least one power setting adjustment for the at least one terminal specific for a channel or a reference signal comprises a P0_PUSCH, P0_PUCCH, P0_PRACH or a P0_SRS parameter adjustment. 10. The apparatus of any of claims 7 and 8, wherein the at least one power setting adjustment for the at least one terminal is generic for all channels and reference signals and/or all terminals in a cell. 11. The apparatus of any of claims 1 to 10, wherein the at least one power setting adjustment for the at least one terminal comprises at least one of a power offset adjustment for the terminal, a pathloss offset adjustment for the terminal or an information about satellite gain setting adjustment for the terminal. 12. The apparatus of claims 1 to 11, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to: receive measurements collected at the satellite; and determine the at least one gain setting adjustment for the satellite based on the measurements. 13. The apparatus of claim 12, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to: provide the at least one gain setting adjustment for the satellite to the satellite. 14. The apparatus of any of claims 1 to 13, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to: receive the at least one gain setting adjustment for the satellite determined at the satellite. 15. The apparatus of any of claims 1 to 14, wherein the apparatus is a base station. 16. The apparatus of claim 15, wherein the base station is coupled to the satellite via a gateway. 17. An apparatus comprising: at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: receive at least one power setting adjustment for at least one terminal, wherein the at least one power setting adjustment for the at least one terminal is determined based on at least one gain setting adjustment for a satellite; and adjust at least one power setting based on the at least one power setting adjustment for the at least one terminal. 18. The apparatus of claim 17, wherein the at least one power setting for the at least one terminal comprises at least one uplink transmission power setting. 19. The apparatus of any of claims 17 to 18, wherein the at least one power setting adjustment for the at least one terminal is received via at least one broadcast signal or at least one dedicated signal. 20. The apparatus of any of claims 17 to 19, wherein the at least one power setting adjustment for the at least one terminal is specific for a terminal or generic for a plurality of terminals. 21. The apparatus of any of claims 17 to 20, wherein the at least one power setting adjustment for the at least one terminal is specific for a channel or a reference signal or generic for a plurality of channels and/or a plurality of reference signals. 22. The apparatus of claim 21, wherein the at least one power setting adjustment for the at least one terminal specific for a channel or a reference signal comprises at least one P0_PUSCH, P0_PUCCH, P0_PRACH or a P0_SRS parameter adjustment. 23. The apparatus of any of claims 20 and 21, wherein the at least one power setting adjustment for the at least one terminal is generic for all channels and reference signals and/or all terminals in a cell. 24. The apparatus of any of claims 17 to 23, wherein the at least one power setting adjustment for the at least one terminal comprises a power offset adjustment or a pathloss offset adjustment. 25. A method comprising: determining at least one power setting adjustment for at least one terminal based on at least one gain setting adjustment for a satellite; and providing the least one power setting adjustment for the at least one terminal to the at least one terminal. 26. The method of claim 25, wherein the determining the at least one power setting adjustment for the at least one terminal based on the at least one gain setting is based on information received from the satellite. 27. The method of any of claims 25 and 26, wherein the at least one gain setting adjustment for the satellite comprises at least one uplink gain setting adjustment for the satellite, at least one downlink gain setting adjustment for the satellite and/or at least one difference between an uplink gain setting adjustment for the satellite and a downlink gain setting adjustment for the satellite. 28. The method of claim 27, wherein the at least one uplink gain setting adjustment for the satellite comprises at least one of an uplink reception gain setting adjustment on an access link or an uplink transmission gain setting adjustment on a feeder link; or wherein the at least one downlink gain setting adjustment for the satellite comprises at least one of an downlink reception gain setting adjustment on a feeder link or a downlink transmission gain setting adjustment on an access link. 29. The method of any of claims 25 to 28, wherein the at least one power setting adjustment for the at least one terminal comprises at least one uplink power setting adjustment. 30. The method of any of claims 25 to 29, wherein the at least one power setting adjustment for the at least one terminal is provided to the at least one terminal via at least one broadcast signal or at least one dedicated signal. 31. The method of any of claims 25 to 30, wherein the at least one power setting adjustment for the at least one terminal is specific for a terminal or generic for a plurality of terminals. 32. The method of any of claims 25 to 31, wherein the at least one power setting adjustment for the at least one terminal is specific for a channel or a reference signal or generic for a plurality of channels and/or a plurality of reference signals. 33. The method of claim 32, wherein the at least one power setting adjustment for the at least one terminal specific for a channel or a reference signal comprises a P0_PUSCH, P0_PUCCH, P0_PRACH or a P0_SRS parameter adjustment. 34. The method of any of claims 31 and 32, wherein the at least one power setting adjustment for the at least one terminal is generic for all channels and reference signals and/or all terminals in a cell. 35. The method of any of claims 25 to 34, wherein the at least one power setting adjustment for the at least one terminal comprises at least one of a power offset adjustment for the terminal, a pathloss offset adjustment for the terminal or an information about satellite gain setting adjustment for the terminal. 36. The method of claims 25 to 35, comprising: receiving measurements collected at the satellite; and determining the at least one gain setting adjustment for the satellite based on the measurements. 37. The method of claim 36, comprising: providing the at least one gain setting adjustment for the satellite to the satellite. 38. The method of any of claims 25 to 37, comprising: receiving the at least one gain setting adjustment for the satellite determined at the satellite. 39. The method of any of claims 25 to 38, wherein the method is performed by a base station. 40. The method of claim 39, wherein the base station is coupled to the satellite via a gateway. 41. A method comprising: receiving at least one power setting adjustment for at least one terminal, wherein the at least one power setting adjustment for the at least one terminal is determined based on at least one gain setting adjustment for a satellite; and adjusting at least one power setting based on the at least one power setting adjustment for the at least one terminal. 42. The method of claim 41, wherein the at least one power setting for the at least one terminal comprises at least one uplink transmission power setting. 43. The method of any of claims 41 to 42, wherein the at least one power setting adjustment for the at least one terminal is received via at least one broadcast signal or at least one dedicated signal. 44. The method of any of claims 41 to 43, wherein the at least one power setting adjustment for the at least one terminal is specific for a terminal or generic for a plurality of terminals. 45. The method of any of claims 41 to 44, wherein the at least one power setting adjustment for the at least one terminal is specific for a channel or a reference signal or generic for a plurality of channels and/or a plurality of reference signals. 46. The method of claim 45, wherein the at least one power setting adjustment for the at least one terminal specific for a channel or a reference signal comprises at least one P0_PUSCH, P0_PUCCH, P0_PRACH or a P0_SRS parameter adjustment. 47. The method of any of claims 44 or 45, wherein the at least one power setting adjustment for the at least one terminal is generic for all channels and reference signals and/or all terminals in a cell. 48. A computer program comprising computer executable instructions which when run on one or more processors perform the steps of any of the methods of claims 25 to 47. 49. An apparatus comprising means for: determining at least one power setting adjustment for at least one terminal based on at least one gain setting adjustment for a satellite; and providing the least one power setting adjustment for the at least one terminal to the at least one terminal. 50. An apparatus comprising means for: receiving at least one power setting adjustment for at least one terminal, wherein the at least one power setting adjustment for the at least one terminal is determined based on at least one gain setting adjustment for a satellite; and adjusting at least one power setting based on the at least one power setting adjustment for the at least one terminal. |
The composite channel transfer function H DL_tot (f) for the DL communications scenario may be expressed as follows.
The total interference l DL_tot (f) for the DL communications scenario may be expressed as follows.
For the DL communications scenario the strategies of the satellite to adjust a satellite gain G DL,sat (f, t ) or G DL,sat (t) may be to apply constant or quasi-constant gain or may be seeking to invert the channel response.
In a constant gain implementation, a satellite gain G DL,sat (f, t ) may be a constant or it may be changing slowly. In particular, it may not depend on a transmitted UL or DL signal. In a constant equivalent isotopically radiated power (EIRP) implementation, a satellite gain G DL,sat (t) may be determined so that the satellite transmits a constant average power P SAT,0,DL :
Interference may be neglected for the sake of simplicity. It may be noted that the transmitted power P gNB at the gNB may change with the load (e.g. with the number of transmitted physical resource blocks (PRBs)).
In a constant power spectral density (PSD) implementation, a satellite gain G DL (f, t) may be determined such that the power per subcarrier is equalized. The constant PSD may lead to amplifying subcarriers which have no signal. For instance, assume at time t 0 in DL the gNB schedules a UE1 on one bandwidth part (BWP) BWP1 and at t 1 (e.g. one subframe later) another UE2 on another BWP2 is activated and scheduled. The BWP1 will continue to be amplified as before and BWP2 will be brought to the same level as BWP1 . A negative effect in this approach may be the amplification of noise when no signal is present, leading to system interference.
In another implementation, a satellite gain G DL,sat (f, t ) may be determined so that the satellite transmits a constant average power P SAT,0,DL per frequency. The satellite may equalize the feeder link by means of feeder link pilots. In that case the satellite is able to adjust the gain considering the channel only:
The feeder link pilots may be part of a logical side channel which is not visible in the access link. Thus the feeder link pilots could be separate from the GW payload or gNB signal, and not be part of the protocol stack shown in figures 1b and 1c. The feeder link pilots may be transmitted on an additional physical channel (e.g. on a carrier or subcarrier adjacent to the feeder link). The feeder link pilots may also be interleaved in time or frequency in the feeder link, transparent to the GW payload or gNB signal. The feeder link pilots may also be a downlink reference signal (DRS) that the gNB is transmitting in DL. This implementation may require that the satellite has been configured by the gNB to recognize the DRS transmissions. Figure 4b shows a schematic representation of radio channel parameters H UL_f (f), I UL_f (f), G DL (f,t), H UL_a (f) and I UL_a (f) in a non-terrestrial network in an UL communications (i.e. UE to /gNB via satellite) scenario. H UL_f (f) may refer to a transfer function on a feeder link for the UL communications scenario. I UL_f (f) may refer to interference on a feeder link for the UL communications scenario. G UL (f,t) may refer to a satellite gain for the UL communications scenario. H UL_a (f) may refer to a transfer function on an access link for the UL communications scenario. I UL_a (f) may refer to interference on an access link for the UL communications scenario. It will be understood that the transfer function H UL_f (f) on the feeder link for the UL communications scenario and the transfer function H DL_f (f) on the feeder link for the DL communications scenario may be different. Likewise, the transfer function H UL_a (f) on the access link for the UL communications scenario and the transfer function H DL_a (f) on the access link for the DL communications scenario may be different. The interference I UL_f (f) on the feeder link for the UL communications scenario and the interference I DL_f (f) on the feeder link for the DL communications scenario may be different. The interference I UL_a (f) on the access link for the UL communications scenario and the interference I DL_a (f) on the access link for the DL communications scenario may be different. The received signal Y SAT (f) at the satellite from a single UE for the UL communications scenario may be expressed as follows. X(f) may refer to a transmitted signal from the single UE. The received signal at the gNB Y gNB (f) from the single UE for the UL communications scenario may be expressed as follows. _ _ The satellite gain in G UL, sat (f, t) for the UL communications scenario comprises an access and a feeder link gain component and may be expressed as follows. G a.rx (f,t) may refer to a satellite gain for reception on access link for the UL communications scenario. G f.tx (f,t) may refer to a satellite gain for transmission on feeder link for the UL communications scenario. H UL_tot (f) may refer to a composite channel transfer function for the UL communications scenario. l UL_tot (f) may refer to a total interference for the UL communications scenario.
The composite channel transfer function H UL_tot (f) for the UL communications scenario may be expressed as follows.
The total interference l UL_tot (f) for the UL communications scenario may be expressed as follows.
For the UL communications scenario the strategies of the satellite to adjust a satellite gain G UL,SAT ( f, t) or G UL,SAT (t) may be to apply constant or quasi-constant gain or may be seeking to invert the channel response.
In a constant gain implementation, a satellite gain G UL,sat (f, t ) may be a constant or it may be changing slowly. In particular, it may not depend on the transmitted UL or DL signal. In a constant equivalent isotopically radiated power (EIRP) scheme, a satellite gain G UL (t ) may be determined such that the satellite always emits a predefined average transmit power P SAT,0,UL · In this case the satellite gain G UL (t ) may not depend on the frequency, but may depend on the frequency responses of the access links and their power:
It may be noticed that the satellite gain G UL (t ) depends on the predefined average transmit power P SAT,0, UL ·
For instance, assume at time to, ten close UEs are scheduled. The satellite gain G UL (t ) may be smaller. If at time t 1 (e.g. one subframe later) two far UEs are scheduled, then the satellite gain G UL (t ) may be larger.
Even the number of physical resource blocks (PRBs) may have an impact: if at to two UEs with two PRBs are scheduled (e.g. low bit rate UEs), then the satellite gain G UL (t ) may be larger, and if at ti the same two UEs or similar two UEs (at similar distance) are scheduled with twenty PRBs, the satellite gain G UL (t ) may be smaller (e.g. reduced by 10 dB).
In a constant power spectral density (PSD) implementation, a satellite gain G UL (f, t) may be determined such that the power per subcarrier is equalized. This implementation may lead to amplification of noise when some subcarriers do not carry a signal.
In a constant received power at GW/gNB implementation, a satellite gain G UL (f, t ) may be determined such that a received power P gNB,Rx,UL at gNB is constant. There may be power control on the feeder link, but this may look similar to the case above, assuming that the feeder link does not change too fast. In light of the above, it will be understood that the satellite gain settings for the UL communications scenario (e.g. G UL (f, t) or G UL (t ) ) may differ from the satellite gain settings for the DL communications scenario (e.g. G DL (f, t) or G DL (t)). A problem in conventional systems is that a UE may assume reciprocity between satellite gain settings for the UL communications scenario and the satellite gain settings for the DL communications scenario and therefore may assume reciprocity between an UL pathloss and a DL pathloss. As a result, UE UL transmission power settings may be determined based on the DL pathloss as opposed to the UL pathloss.
This can be read for example from the power control equation in 3GPP TS 38.213 (section 7.1.1) for a physical uplink shared channel (PUSCH) reproduced below.
This can also be read for example from the power control equation in 3GPP TS 38.213 (section 7.2.1) for a physical uplink control channel (PUCCH) reproduced below. This can also be read for example from the power control equation in 3GPP TS 38.213 (section 7.3.1) for a sounding reference signal (SRS) reproduced below. This can also be read for example from the power control equation in 3GPP TS 38.213 (section 7.4.1) for a physical random access channel (PRACH) reproduced below. In these equations, PL b, f , c is a pathloss for the active UL BWP b of carrier f based on the DL RS associated with the PRACH transmission on an active DL BWP of serving cell c. PL b, f ,c ( q d ) may be defined as a referenceSignalPower higher layer filtered reference signal received power (RSRP), for example based on the Secondary Synchronization Signal (SSS) in a synchronization signal block (SSB). The referenceSignalPower may be defined as SS-PBCH-BlockPower (average energy per resource element (EPRE) of the resource elements that carry secondary synchronization signals in dBM that the NW used for SSB transmission). It may be signalled in an information element (defined in TS 38.331) ServingCellConfigCommonSIB. In conventional systems, the UE may calculate UE UL transmission power settings P PUSCH , P PUCH , P SRS and P PRACH for PUSCH, PUCCH, SRS and PRACH by measuring a DL pathloss based, for example, on reference signal received power (RSRP). Such calculation may be ineffective. The reciprocity assumption is erroneous because the UL pathloss may depend on the UL satellite gain settings (e.g. G UL (f, t) or G UL (t )) whereas the DL pathloss may depend on DL satellite gain settings (e.g. G DL (f, t) or G DL (t )) and as discussed above the UL satellite gain settings may differ from the DL satellite gain settings.
Furthermore, the UL satellite gain settings and DL satellite gain settings may change independently, further rendering the existing UE UL power setting mechanisms ineffective.
One or more aspects of this disclosure address this problem.
One or more aspects of this disclosure relate to techniques employed by the satellite, the GW and/or the gNB to determine UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings.
One or more aspects of this disclosure relate to an autonomous gain control (AGO) technique wherein the satellite may determine the UL satellite gain settings and/or DL satellite gain settings in an autonomous fashion. The satellite may perform UL measurements and/or DL measurements. The satellite may determine UL satellite gain settings based on the UL measurements and/or DL satellite gain settings based on the DL measurements. The satellite may inform the gNB about the UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings, for example via a side channel, such as the earlier mentioned TT&C control channel (via the GW). The gNB may determine UE UL transmission power settings based on the UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings. The determination of UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings may take place more or less frequently. The determination of UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings may take place in a step-wise fashion. The gNB may provide the UE UL transmission power settings to one or more UEs. One or more aspects of this disclosure relate to an alternative technique wherein the satellite may perform UL measurements and/or DL measurements and may inform the gNB of the UL measurements and/or DL measurements (via the GW). The gNB may determine the UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings based on the UL measurements and/or the DL measurements. The gNB may instruct the satellite (via the GW) to take the UL satellite gain settings and DL satellite gain settings into use The gNB may determine UE UL transmission power settings based the satellite gain settings for UL communications, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings. The gNB may provide the UE UL transmission power settings to one or more UEs. One or more aspects of this disclosure relate to configuring the gNB to periodically or aperiodically communicate with the satellite (via the GW) to indicate when specific operations (e.g. performing UL measurements and/or DL measurements, determining UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings, use UL satellite gain settings and/or DL satellite gain settings determined by the GW) need to be performed. The communication may be performed via control communication/signalling between the gNB and the GW. The control communication/signaling may take place via one or more sidelink (e.g. out-band or in-band) channels. In one variant the GW may inform the gNB about both absolute UL satellite gain settings and DL satellite gain settings. In one variant the GW may inform the gNB about absolute UL satellite gain settings, DL satellite gain settings, a difference between the UL satellite gain settings and DL satellite gain settings and an offset. In one variant the GW may inform the gNB about a difference between the UL satellite gain settings and DL satellite gain settings. In one variant the GW may inform the gNB about a difference (i.e. delta) to a previous UL satellite gain settings, DL satellite gain settings and/or a difference between the UL satellite gain settings and DL satellite gain settings. In one variant the satellite may do so if a threshold has been reached. The informing of an absolute UL satellite gain settings and/or DL satellite gain settings may be of relevance even when the difference between UL satellite gain settings and DL satellite gain settings has not changed, when the UL satellite gain settings and/or DL satellite gain settings by the satellite do not correspond to actual pathloss changes, for instance because power limitations have been reached. In that case it may be helpful for the gNB to adjust UE UL power settings as well. One or more aspects of this disclosure relate to configuring the gNB to determine UE UL transmission power settings based on UL satellite gain settings, DL satellite gain settings and/or a difference between the UL satellite gain settings. The gNB may provide the UE UL transmission power settings via broadcast signalling to a plurality of (e.g. all) UEs or via dedicating signalling (e.g. RRC signalling) to a UE. The gNB may provide the UE UL transmission power settings via transmit power control (TPC) commands. One or more aspects of this disclosure relate to configuring the gNB to provide TPC commands for one or more (e.g. all) UL channels (e.g. PUSCH, PUCCH, PRACH) and/or one or more of (e.g. all) reference signals (e.g. SRS) to compensate for the effective UL pathloss changes. In a first variant, the GW/gNB may provide one or more P0 parameters (e.g. P 0_PUSCH , P 0_PUCCH , P 0_SRS or P 0_PRACH ) via broadcast signalling. The one or more P 0 parameters may be included in a broadcast system information (SI) message. For example, UEs may be paged and then may start listening to the broadcast SI message. Alternatively, the one or more P0 parameters (e.g. P 0_PUSCH , P 0_PUCCH , P 0_SRS or P 0_PRACH ) may be encoded in a broadcast signal such as the group common (GC) -PDCCH. In a second variant, the gNB may provide one or more P 0 parameters (e.g. P 0_PUSCH , P 0_PUCCH , P 0_SRS or P 0_PRACH ) via dedicated signalling. In a third variant, the gNB may use dedicated signalling to provide UE UL transmission power settings for a specific UE and for a specific UL channels (e.g. PUSCH or PUCCH) and/or a specific reference signal (e.g. SRS). For instance, the GW/gNB may send a TPC command in downlink control information (DCI) format_0_0 or format_0_1 or format_2_2 (see 38.213 section 7) to adjust the PUSCH and PUCCH power. The GW/gNB may send a TPC command in DCI format_2_2 or format_2_3 to adjust the SRS power. As also the PRACH may be affected a new DCI format may be introduced to adjust the PRACH. Alternatively or additionally, a new TPC command s b, f , c (i, l) may be introduced that may be applied for one or more (e.g. all) UEs and for one or more of (e.g. all) UL channels (e.g. PUSCH, PUCCH, PRACH) and/or one or more of (e.g. all) reference signals (e.g. SRS). The new TPC command may amount to a DCI carrying a TPC command for some or all UEs on GC-PDCCH. The new parameter s b, f , c (i, l) may be used in the power control equations in 3GPP TS 38.213 (sections 7.1.1, 7.2.1, 7.3.1 and 7.4.1).
In a fourth variant, the gNB may provide a Gain_correction parameter to one or more (e.g. all) UEs as shown in the power control equations below. The Gain_correction parameter may compensate for the difference in UL satellite gain settings and DL satellite gain settings. As already discussed the UL satellite gain settings may affect the UL pathloss. Thus, UL satellite gain settings changes may lead to UL pathloss changes. This variant addresses directly the underlying mechanism of UL satellite gain settings changes, considering that the Uu interface consists of access link, feeder link and the transparent satellite. Furthermore, the DL satellite gain settings may affect what the UE is measuring as DL pathloss. The DL pathloss is part of UE UL power setting formula in terms of PL. Therefore the Gain_correction also addresses the satellite DL gain changes. The Gain_correction thus will be compensating for the difference in UL satellite gain settings and DL satellite gain settings that the satellite is introducing.
The Gain_correction parameter may be scaled with the slope parameter a and therefore updating the Gain_correction parameter may be different from updating the P 0 parameters or the closed loop TPC commands. The Gain_correction may be sent via dedicated RRC signaling (e.g. along with P 0 parameters and a) or via PDCCH (e.g. along with the closed loop TPC commands).
It may be noted that current TPC commands are sent in dedicated signalling. For the purpose of the proposed method the TPC commands may be broadcast and may be read by a plurality of connected UEs (third and fourth variants).
It may also be noted that broadcasting updates of a P 0 parameter on GC-PDCCH or sending a TPC command for s b,f,c (i, l ) or for Gain_correction on GC-PDCCH may amount to the same.
It may also be noted that a P 0 parameter may signalled as an increment similar to TPC commands, for example when not all UEs are configured with the same P 0 parameter. Figure 5 shows a schematic representation of a signalling diagram of a method of managing at least one UL transmission power settings for at least one UE in a non terrestrial network. In step 1, the satellite, the GW and/or the gNB may cooperate to determine UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings.
In step 2, the gNB may be aware of the UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings. If the UL satellite gain settings, DL satellite gain settings and/or a difference between UL satellite gain settings and DL satellite gain settings have changed sufficiently it may decide to determine UE UL transmission power settings for UE1 and UE2. For example, if a difference satellite gain settings between UL satellite gain settings and DL satellite gain settings change is above a threshold, the UE UL transmission power settings may be determined. Otherwise, the UE UL transmission power settings may not be updated (at least not because of the satellite).
In step 3, the gNB may provide the UL transmission power settings for UE1 and UE2.
Figure 6 shows a schematic representation of a block diagram of a method of managing at least UL power setting for at least one terminal in a NTN. The method may be performed by a gNB.
In step 602, the gNB may obtain at least one gain setting adjustment for a satellite. The at least one gain setting for the satellite may comprise at least one UL gain setting (e.g. G UL (f, t) or G UL (t)), DL gain setting (e.g. G DL (f , t) or G DL (t)) and/or difference between UL gain setting and DL gain setting for the satellite (e.g. G UL (f, t ) - G DL (f, t) or G UL (t) - G DL (t)). The at least one UL gain setting for the satellite (e.g. G UL (f, t ) or G UL (t )) may comprise at least one of an UL reception gain setting (e.g. G a,rx (f, t ) or an UL transmission gain setting (e.g. G f ,tx (f, t)). The at least one gain DL setting for the satellite (e.g. G DL (f, t) or G DL (t )) may comprise at least one of a DL reception gain setting (e.g. G f ,xr (f, t ) or a DL transmission gain setting (e.g. G a ,tx (f, t)).
In an implementation, the gNB may receive UL measurements and/or DL measurements collected at the satellite. The GW/gNB may determine the at least one gain setting adjustment for the satellite based on the measurements. The GW/gNB may provide to the satellite the at least one gain setting adjustment for the satellite.
In another implementation, the satellite may determine the least one gain setting adjustment for the satellite. The gNB may receive the at least one gain setting adjustment for the satellite from the satellite.
In step 604, the gNB may determine at least one power setting adjustment for at least one terminal based on the at least one gain setting adjustment for the satellite obtained in step 602. The at least one power setting adjustment for the at least one terminal may comprise at least one UL transmission power setting adjustment.
The at least one power setting adjustment for the at least one terminal may be specific for a terminal or generic for a plurality of (e.g. all) terminals. The at least one power setting adjustment for the at least one terminal may be specific for a channel (e.g. PUSCH, PUCCH or PRACH) or a reference signal (e.g. SRS). The at least one power setting adjustment for the at least one terminal specific for a channel (e.g. PUSCH, PUCCH or PRACH) or a reference signal (e.g. SRS) may comprise a P 0 (e.g. P 0_PUSCH , P 0_PUCCH , P 0_PRACH or a P 0_SRS ) parameter adjustment. The at least one power setting adjustment for the at least one terminal may be generic for one or more channels (e.g. PUSCH, PUCCH or PRACH) and one or more reference signals (e.g. SRS). The at least one power setting adjustment may comprise a power offset (e.g. s b, f , c (i, l) ) adjustment or a pathloss offset (e.g. Gain_correction) adjustement. In step 606, the gNB may provide the at least one power setting adjustment for the at least one terminal determined in step 604 to the at least one terminal. The at least one power setting adjustment for the at least one terminal may be provided via at least one broadcast signal or at least one dedicated signal. Figure 7 shows a schematic representation of a block diagram of a method of managing at least one UL power setting for at least one terminal in a NTN. The method may be performed by the terminal. In step 702, the terminal may receive at least one power setting adjustment for at least one terminal. The at least one power setting adjustment for the at least one terminal may be determined by a gNB based on at least one gain setting adjustment for a satellite. The at least one power setting adjustment for the at least one terminal may be provided via at least one broadcast signal or at least one dedicated signal. The at least one power setting adjustment for the at least one terminal may be specific for a terminal or generic for a plurality of (e.g. all) terminals. The at least one power setting adjustment for the at least one terminal may be specific for a channel (e.g. PUSCH, PUCCH or PRACH) or a reference signal (e.g. SRS). The at least one power setting adjustment for the at least one terminal specific for a channel (e.g. PUSCH, PUCCH or PRACH) or a reference signal (e.g. SRS) may comprise a P 0 (e.g. P 0_PUSCH , P 0_PUCCH , P 0_PRACH or a P 0_SRS ) parameter adjustment. The at least one power setting adjustment for the at least one terminal may be generic for one or more channels (e.g. PUSCH, PUCCH or PRACH) and one or more reference signal (e.g. SRS). The at least one power setting adjustment may comprise a power offset (e.g. s b, f , c (i, l) ) adjustment or a pathloss offset (e.g. Gain_correction) adjustement. In step 704, the terminal may adjust at least one power setting based on the at least one power setting adjustment for the at least one terminal. The at least one power setting may be an UL transmission power setting. The at least one power setting may be specific for a channel (e.g. PUSCH, PUCCH or PRACH) or a reference signal (e.g. SRS). The at least one power setting may comprise a P PUSCH , P PUCC H, P PRACH or a P SR . Figure 8 shows a schematic representation of non-volatile memory media 800a (e.g. computer disc (CD) or digital versatile disc (DVD) and 800b (e.g. universal serial bus (USB) memory stick) storing instructions and/or parameters 802 which when executed by a processor allow the processor to perform one or more of the steps of the above methods. It is noted that while the above describes example embodiments, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention. The embodiments may thus vary within the scope of the attached claims. In general, some embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although embodiments are not limited thereto. While various embodiments may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof. The embodiments may be implemented by computer software stored in a memory and executable by at least one data processor of the involved entities or by hardware, or by a combination of software and hardware. Further in this regard it should be noted that any of the above procedures may represent program steps, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. The software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD. The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processors may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), gate level circuits and processors based on multi-core processor architecture, as non-limiting examples. Alternatively or additionally some embodiments may be implemented using circuitry. The circuitry may be configured to perform one or more of the functions and/or method steps previously described. That circuitry may be provided in the base station and/or in the communications device. As used in this application, the term “circuitry” may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analogue and/or digital circuitry); (b) combinations of hardware circuits and software, such as: (i) a combination of analogue and/or digital hardware circuit(s) with software/firmware and (ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as the communications device or base station to perform the various functions previously described; and (c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation. This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example integrated device. The foregoing description has provided by way of exemplary and non-limiting examples a full and informative description of some embodiments However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings will still fall within the scope as defined in the appended claims.