Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B7/00—Radio transmission systems, i.e. using radiation field
  • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
  • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
  • H04B7/0413—MIMO systems
  • H04B7/0452—Multi-user MIMO systems
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B7/00—Radio transmission systems, i.e. using radiation field
  • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
  • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
  • H04B7/04013—Intelligent reflective surfaces
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B7/00—Radio transmission systems, i.e. using radiation field
  • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
  • H04B7/10—Polarisation diversity; Directional diversity

Definitions

• Various examples of the disclosure generally pertain to communication, via a coverage en- hancing device, between a transmitter communication device and multiple receiver communi- cation devices, as well as communication, via a coverage enhancing device, between multi- ple transmitter communication devices and a receiver communication device.
• CEDs coverage enhancing devices
• NCRs Network Controlled Repeaters
• RRD re-configura- ble relaying devices
• CEDs can also be referred to as network enhancement devices, since they generally enhance coverage, rank, and/or localizations.
• RRDs are re-configurable reflective devices, sometimes also referred to as reflecting large intelli- gent surfaces (LISs). See, e.g., Huang, C., Zappone, A., Alexandropoulos, G. C., Debbah, M., & Yuen, C. (2019). Reconfigurable intelligent surfaces for energy efficiency in wireless communication.
• An RRD can be implemented by an array of antennas that can reflect incident electromag- netic waves/signals.
• the array of antennas can be semi-passive. Semi-passive can corre- spond to a scenario in which the antennas can impose a variable phase shift and typically provide no signal amplification.
• NCRs can amplify a signal for each antenna element of a respective array.
• An NCR can implement one of reflection for coverage enhancement, amplify-forward for cover- age enhancement, or decode-forward for coverage enhancement. Each antenna element may impose an antenna-element-specific amplitude gain and phase shift (i.e., provide signal amplification and variable phase shift).
• an NCR may in- clude multiple antenna arrays, e.g., one for receiving and one for transmitting. There may be signal processing in the baseband in between receiving and transmitting.
• an input spatial direction (or simply, input direction) from which incident signals on a radio link are accepted by a CED and an output spatial direction (or simply, output direc- tion) into which the incident signals are redirected by the CED can be re-configured by changing a phase relationship (and, where possible, amplitude relationship) between the an- tennas. This corresponds to configuring a spatial filter at the CED.
• An access node may transmit signals to a wireless communication device (UE); some- times also referred to as terminal) via a CED.
• the CED may accept or receive the incident signals from an input spatial direction and forward or transmit the incident signals in an out- put spatial direction to the UE.
• the AN may transmit the signals using a beam directed to the CED. Scenarios are possible where multiple UEs are served by the AN via a CED. See WO 2021 109345 A1. SYP349050WO01 2 E39500WO SN SUMMARY There is a need for advanced techniques of communicating via a CED. Specifically, there is a need for techniques which facilitate communicating contemporaneously with multiple com- munication devices via a CED.
• Various techniques disclosed herein facilitate communicating between a first communication device (CD) and multiple second CDs via a CED. This can be referred to as multi-device transmission (MDT).
• MDT multi-device transmission
• Different data streams can be provided by the first CD to the multiple second CD.
• multiple UEs can be served by an AN via a CED.
• Uplink and/or downlink transmission of data is possible using MDT.
• multiple data streams are transmitted by the AN using two polarizations of the transmitted signals and then forwarded at the CED. Precoding at the AN takes the overall channel towards the UEs into account, this channel also being dependent on the spatial filter applied at the CED.
• the spatial filter at the AN can be determined jointly with the precoder at the AN, to facilitate efficient precoding. This allows forwarding of one data stream to a first UE and forwarding of a second data stream to a second UE, e.g., with low or no interference at the UEs.
• Various techniques pertain to scheduling strategies at the AN. According to examples, scheduling is based on polarization indications of the UEs. The UEs can indicate how their receiver operates with respect to polarization of incident signals. Different receiver types can be co-scheduled. According to examples, a method of operating an AN is disclosed.
• the AN is associated with a communications network, e.g., a cellular network (in which case the AN would be referred to as base station, BS).
• the AN communicates wirelessly with a plurality of UEs via a CED.
• the method includes requesting, from each UE of the plurality of UEs, a respective polariza- tion indication.
• the polarization indication is indicative of whether the respective UE includes a first rank-1 receiver or transmitter type or a second rank-1 receiver or transmitter type.
• Rank-1 indicates that the UE can only receive or transmit a single data stream at a time.
• the first rank-1 receiver or transmitter type is configured to receive or transmit a linear polari- zation.
• the second rank-1 receiver or transmitter type is configured to receive or transmit a circular polarization. It is to be understood that the features mentioned above and those yet to be explained below may be used not only in the respective combinations indicated, but also in other combina- tions or in isolation without departing from the scope of the invention.
• FIG.1 schematically illustrates a rank-1 linear polarized receiver according to various exam- ples.
• FIG.2 schematically illustrates a rank-1 circular polarized receiver according to various ex- amples.
• FIG.3 schematically illustrates the probability of a certain power required for zero-forcing precoding at the BS for random realizations of relative orientations of UEs with respect to a CED according to various examples, wherein in FIG.3 pairs of UEs are co-scheduled that both have rank-1 linear polarized receiver types.
• FIG.4 schematically illustrates the probability of a certain power required for zero-forcing precoding at the BS for random realizations of relative orientations of UEs with respect to a CED according to various examples, wherein in FIG.4 pairs of UEs are co-scheduled which include one UE having rank-1 linear polarized receiver type and another UE having rank-1 circular polarized receiver type, respectively.
• FIG.5 illustrates a communication system including a BS and a UE according to various ex- amples.
• FIG.6 schematically illustrates further details with respect to the BS and the UE according to various examples.
• FIG.7 schematically illustrates communication between multiple UEs in the BS via a CED.
• FIG.8 schematically illustrates details with respect to a CED.
• FIG.9 is a flowchart of a method according to various examples.
• FIG.10 is a signaling diagram according to various examples.
• FIG.11 is a signaling diagram according to various examples.
• DETAILED DESCRIPTION Some examples of the present disclosure generally provide for a plurality of circuits or other electrical devices. All references to the circuits and other electrical devices and the function- ality provided by each are not intended to be limited to encompassing only what is illustrated and described herein. While particular labels may be assigned to the various circuits or other electrical devices disclosed, such labels are not intended to limit the scope of operation for the circuits and the other electrical devices. Such circuits and other electrical devices may be combined with each other and/or separated in any manner based on the particular type of electrical implementation that is desired.
• any circuit or other electrical de- vice disclosed herein may include any number of microcontrollers, a graphics processor unit (GPU), integrated circuits, memory devices (e.g., FLASH, random access memory (RAM), read only memory (ROM), electrically programmable read only memory (EPROM), electri- cally erasable programmable read only memory (EEPROM), or other suitable variants thereof), and software which co-act with one another to perform operation(s) disclosed herein.
• any one or more of the electrical devices may be configured to execute a program code that is embodied in a non-transitory computer readable medium programmed to perform any number of the functions as disclosed.
• a wireless communication system includes one or more transmitter CDs and one or more receiver CDs.
• the wireless communication system can be implemented by nodes of a wireless communication network, e.g., a radio-access network (RAN) of a 3GPP-specified cellular network (NW).
• RAN radio-access network
• NW 3GPP-specified cellular network
• TX Transmitter
• RX Receiver
• a BS provides DL transmission to multiple UEs. In other ex- amples, multiple UEs provide UL transmissions to a given BS.
• the wireless communication system may, in some scenarios, in- clude a CED.
• the CED supports, e.g., UL and/or DL transmission or SL transmission.
• MDT is employed. This means that the BS contemporane- ously transmits two data streams to two UEs and the CED forwards one data stream to a first UE and another data stream to a second UE.
• each UE transmits a data stream and the data stream is multiplexed at the CED and then de-multiplexed at the BS.
• this de-multiplexing at the CED or at the BS is implemented using multiple polarizations, e.g., two orthogonal linear polarizations (H-POL and V-POL) or two or- thogonal circular polarization (LHCP and RHCP).
• H-POL and V-POL two orthogonal linear polarizations
• LHCP and RHCP two or- thogonal circular polarization
• Examples will be primarily disclosed in the context of an implementation of the CED by an RRD that is capable to adjust the phase of incident signals individually for each one of the multiple polarizations, but is not capable of adjusting the amplitude.
• MDT for UEs that have a rank-1 receiver or transmitter type is considered. These UEs may be referred to as single-polarized UEs. While dually polarized UEs is the dominant case, single polarized UEs can find applications in low-cost-device type of sys- tems, e.g., Internet of Things (IoT), sensors, etc. Such single-polarized UEs have a compara- tively simple radio frequency (RF) hardware configuration.
• RF radio frequency
• a single polarized UE includes a receiver (or a transmitter) that has a single baseband pro- cessing RF circuitry.
• a rank-1 receiver type has a single analog-to-digital con- verter; and a rank-1 transmitter type has a single digital-to-analog converter.
• a rank-2 re- ceiver type would include two RF processing chains to separately process two data streams.
• FIG.1 illustrates a rank-1 receiver 551 of a first type that is configured to re- ceive a linear polarization (hereinafter, rank-1 linear polarized receiver type).
• the SYP349050WO01 5 E39500WO SN rank-1 receiver 551 includes an antenna element 501 that is sensitive to a given polarization direction, e.g., either H-POL or V-POL.
• the rank-1 linear polarized receiver 551 includes RF processing circuitry such as a filter 511, an amplifier 512, a mixing stage 513 to mix with an intermediate frequency 514 and finally an ADC 515.
• FIG.2 illustrates a rank-1 receiver 552 of a second type that is configured to receive a circu- lar polarization (hereinafter, rank-1 circular polarized receiver type).
• the rank-1 re- ceiver 552 includes two antenna elements 501, 502 that are sensitive to orthogonal polariza- tions (H-POL and V-POL, arbitrarily defined).
• H-POL and V-POL orthogonal polariza- tions
• LHCP linear polarization
• Techniques are disclosed hereinafter to determine suitable CED spatial filters to serve pairs of UEs using polarization MDT.
• Techniques are disclosed that enable the CED to de-multi- plex two incoming data streams from the BS on shared time-frequency resources (and same spatial resource), for DL transmission.
• the CED can multiplex two in- coming data streams, one from each UE.
• investigating the ensuing throughputs reveals that the type of UE receiver or transmitter (for example rank-1 circular polarized type or rank-1 lin- ear polarized type as discussed above) significantly impacts the achievable rates.
• co-scheduling pairs of UEs to employ the polarization MDT. These options are summarized below in TAB.1.
• the system model analysis is for DL transmission from a BS to two UEs (UE-1, UE-2) via a CED.
• Dually polarized BS and a dually polarized CED are assumed. This means that the BS can transmit and receive individually for two different polarizations, e.g., H-POL and V-POL or LHCP and RHCP.
• the CED has two separate antenna arrays, i.e., for H-POL and V-POL or LHCP and RHCP (the coordinate system of CED is rotated with respect to the coordinate system of the BS).
• BS to CED three beam directions (i) BS to CED, (ii) CED to UE-1, and (iii) CED to UE- 2 are all known. These could be determined using positioning techniques such as triangula- tion, angle of departure, angle of arrival, etc. It is alternatively or additionally possible to use a beam-sweep procedure.
• the CED then performs a beam split per polarization, i.e., polarization-based MDT is em- ployed.
• the polarization precoder i.e., antenna weights – amplitude and phase – for both polariza- tions
• ⁇ ⁇ ⁇ 1,2 ⁇ for UE-1 and UE-2, respec- tively.
• ⁇ ⁇ / ⁇ thus denote beam-splitting ratios for the RRD for the two channels between the BS and UE-1 and the BS and UE-2, respectively.
• the vector [ ⁇ ⁇ ⁇ ⁇ ] can be characterized as follows.
• Equation 6 Assuming zero-forcing precoding applied at the BS, it follows that the beam-splitting ratios at the CED ( ⁇ -variables) are to be optimized as the solution to In other words: this is the minimum power necessary at the BS to invert the channel.
• the ar- guments solving Equation 6 represent the CED configuration that minimizes the necessary transmit power at the BS to create interference free reception at the two UEs and equal re- ceive power at the two UEs. Equation 6 poses an optimization problem that can be solved using a numerical optimization that varies the beam-splitting ratios. It also yields the transmit precoders at the BS, because the channel is inverted according to zero-forcing precoder.
• the reported gains are the minimum gains that are possible; hence, the wording “at least 0.7dB gain” used above.
• circular and linear polarization cf. TAB.1
• This corresponds to rank-1 circular UEs and rank-1 linear UEs.
• the BS has different options to co-schedule UEs based on their polarization indications that are indicative of ⁇ ⁇ , considering that some are rank-1 circular UEs and some are rank-1 lin- ear UEs, cf. TAB.1. The performance of these options is discussed next.
• ⁇ ⁇ [1 ⁇ ].
• Equation 3 can be rewritten as: It is not hard to see that it is optimal (for an optimization considering zero-forcing precoders optimizing the transmit power, cf. Equation 6) to select the ⁇ -variables as, e.g.,
• 1, which implies that
• 0. In other words, this means that there is no beam splitting performed at the RRD.
• the horizontally polarized RRD antennas serve UE-1 and the vertical antennas serve UE-2.
• FIG.3 illustrates the resulting power
• FIG.3 illustrates the frequency of occurrence of the respective power
• the vertical dashed lines refers to the power required to invert the channel (
• the aver- age power required to invert the channel when co-scheduling to rank-1 linear UEs is, in fact, about 4. This is more than for co-scheduling to rank-1 circular UEs.
• the beam split- ting pattern (spatial filter, beam splitting ratios) at the RRD should be optimally configured. If the BS can do arbitrary precoding, the optimal RRD configuration depends on (i) the rota- tions between UEs and the RRD, and (ii) the polarization profile at the UEs.
• TAB.1 option II being the preferred choice over TAB.1: option I.
• CO-SCHEDULING RANK-1 LINEAR UE WITH RANK-1 CIRCULAR UE TAB.1: OPTION III
• Equation 6 a performance ac- cording to FIG.4 is obtained (FIG.4 also corresponds to the optimization results of 3000 ran- dom realizations of angles ⁇ ⁇ ).
• FIG.5 schematically illustrates a communication system 100.
• the communication system 100 includes two CDs 101, 102 that are configured to communicate with each other via a ra- dio link 112.
• the CD 101 is implemented by a BS 101 of a cellular NW and the CD 102 is implemented by a UE 102.
• the UE 102 could be, e.g., a smartwatch, a smart TV, a smart meter, to give just a few ex- amples.
• the UE 102 is a rank-1 linear or circular polarized UE, cf. FIG.1 or FIG.2.
• the techniques described herein could be used for various types of com- munication systems, e.g., also for peer-to-peer communication, etc.
• communica- tion system that is implemented by an BS 101 of a cellular NW and a UE 102.
• FIG.6 illustrates details with respect to the BS 101.
• the BS 101 implements an access node of a communications network, e.g., a 3GPP-specified cellular network.
• the BS 101 includes control circuitry that is implemented by a processor 1011 and a non-volatile memory 1015.
• the processor 1011 can load program code that is stored in the memory 1015.
• the proces- sor 1011 can then execute the program code.
• Executing the program code causes the pro- cessor to perform techniques as described herein, e.g.: transmitting and/or receiving (com- municating) payload data on the data link 112 on the data carrier 111, e.g., via a CED (not shown in FIG.6); performing an optimization to determine precoders based on zero-forcing a channel; obtaining an indication of a receiver or transmitter type from the UE 102; etc.
• FIG.6 also illustrates details with respect to the UE 102.
• the UE 102 includes control cir- cuitry that is implemented by a processor 1021 and a non-volatile memory 1025.
• the proces- SYP349050WO01 12 E39500WO SN sor 1021 can load program code that is stored in the memory 1025.
• the processor can exe- cute the program code. Executing the program code causes the processor to perform tech- niques as described herein, e.g.: transmitting and/or receiving (communicating) payload data on the data link 112 (cf. FIG.1) on the data carrier 111, e.g., via an CED (not shown in FIG. 6); providing an indication of a receiver or transmitter type to the cellular NW, etc.
• FIG.6 also illustrates details with respect to communication between the BS 101 and the UE 102 on the data carrier 111.
• the BS 101 includes an interface 1012 that can access and con- trol multiple antennas 1014.
• the UE 102 includes an interface 1022 that can access and control an antenna 1024.
• the interface 1022 could be implemented as de- scribed in connection with FIG.1 or FIG.2.
• the interface 1012 can each include one or more TX chains and one or more RX chains (the UE 102 may include only a single TX chain and/or only a single RX chain).
• RX chains can include low noise amplifiers, analogue to digital converters, mixers, etc. Analog and/or digital beamforming would be possible.
• phase-coherent transmitting and/or receiving (communicating) can be implemented across the multiple antennas 1014.
• Multi-antenna techniques can be implemented.
• a TX beam By using a TX beam, the direction of signals transmitted by a transmitter of the communica- tion system is controlled. Energy is focused into a respective direction or even multiple direc- tions, by phase-coherent superposition of the individual signals originating from each an- tenna 1014. Thereby, a spatial data stream can be directed.
• the spatial data streams trans- mitted on multiple beams can be independent, resulting in spatial multiplexing multi-antenna transmission; or dependent on each other, e.g., redundant, resulting in diversity multi-input multi-output (MIMO) transmission.
• MIMO diversity multi-input multi-output
• RX beams As a general rule, alternatively or additionally to such TX beams, it is possible to employ RX beams.
• FIG.7 illustrates a variant of the communication system 100.
• FIG.7 illustrates aspects with respect to communicating via a CED 109.
• a UE 102 is served by the BS 101 via the CED 109.
• Another UE 105 (that can be configured as the UE 102, cf. FIG.1, FIG.2, FIG.5, FIG.6) is also served by the BS 101 via the CED 109.
• Different steering vectors at the CED define TX and RX beams 671-672; only beam 671 is directed towards the UE 102.
• Beam 672 is directed towards the UE 105.
• Respective TX or RX beamformers are used at the CED 109.
• a beam 679 of the CED 109 that is directed towards the BS 101 and can be accessed by respective RX or TX beamformers.
• the angles ⁇ , ⁇ ⁇ are known and respective beam man- agement can be implemented at the nodes 101, 102, 105, 109.
• the BS 101 can co-schedule two UEs such as the UEs 102, 105 that are both rank-1 circular UEs, i.e., that both have a rank-1 circular polarized receiver or transmitter type (cf. TAB.1: option I; FIG.2).
• the BS 101 transmits, using H-POL on the beam 679, a data SYP349050WO01 13 E39500WO SN stream directed to the UE 102; and the BS 101 transmits, using V-POL on the beam 679, an- other data stream directed to the UE 105.
• a first sub array of H-POL antenna elements of the CED 109 serves the UE 102 and a second sub-array of V-POL antenna elements of the CED 109 serves the UE 105, respectively employing the beam 671 of the beam 672. This is different when co-scheduling rank-1 linear and rank-1 circular UEs (cf. TAB.1: option III).
• the BS 101 transmits signals that include a superposition of first signals intended for the first UE 102 and second signals intended for the second UE 105.
• a first component of transmit signals transmitted using H-POL includes a mixture / superposi- tion of signals for both UEs; likewise a second component of the transmit signals transmitted using V-POL includes another mixture of signals for both UEs 102, 105.
• a control node 108 that can communicate with the CED 109 on a control link 199.
• the control node 108 is generally optional.
• the CED 109 includes multiple antenna arrays (albeit in FIG.8 only a single array is illustrated), e.g., separate antenna arrays for TX and RX (TX array and RX array)
• TX array and RX array The role of the multiple antenna arrays can be switched; e.g., one array may operate as TX array first and then as RX array, or vice versa.
• an RF/IF signal processing module 670 At the RF/IF signal processing module 670, the RF signals associated with each antenna element 1094 can be processed, e.g., up- and/or down-converted from/to the baseband, combined with each other, split up, phase shifts can be applied, amplification can be applied, etc.
• a respective capability indication that is indicative of whether the respective UE is capa- ble of switching between different rank-1 receiver or transmitter types, e.g., from rank-1 linear polarized receiver type to rank-1 circular polarized receiver type (e.g., from FIG.1 configura- tion to FIG.2 configuration or vice versa). Then, based on such capability indications and as part of the scheduling procedure, it would be possible to request at least one of the UEs to switch to a different rank-1 receiver or transmitter type.
• the channels between the CED and each one of the UEs of a given pair are estimated. This includes determining the relative orientation of the UEs with respect to the CED; i.e., in other words, the g-values of Equation 6 are determined. There are various options for estimating the channels. For instance, a channel sounding pro- cedure may be employed. This can include communication of reference signals in the uplink or in the downlink when a respective spatial filter is activated at the CED 109 that uses a beam to one of the two UEs, respectively (cf.
• the CED 109 could be configured to use a spatial filter that uses the beam 671 for H-POL and V-POL; then reference signals can be communicated using H-POL and V-POL between the BS 101 and the UE 102 to determine SYP349050WO01 15 E39500WO SN ⁇ ⁇ , ⁇ ⁇ for that UE, respectively; the same can be repeated for the UE 105 using the beam 672). It would also be possible to obtain respective orientation indications from the UEs that are indicative of a relative orientation of the respective UE with respect to the CED. Then, the g-values can be calculated based on these orientation indications.
• the transmit precoders can be determined based on the beam-splitting ratios. More specifically, the transmit precoders in the beam-splitting ratios can be determined based on a numerical optimization that varies the beam-splitting ratios, as explained above in connection with Equation 6. This numerical optimization can include constraints that are as- sociated with the physical limitations of the CED to implement the beam splitting ratios. Ex- ample constraints have been disclosed in connection with TAB.2.
• the numerical optimiza- tion includes a goal function that rewards, e.g., the low transmit power as explained in con- nection with Equation 6 and/or the overall data throughput between the BS and the UEs that are co-scheduled.
• a goal function that rewards, e.g., the low transmit power as explained in con- nection with Equation 6 and/or the overall data throughput between the BS and the UEs that are co-scheduled.
• the determination of the spatial filters of the CED based on the beam-splitting ratios can be executed at the BS; in which the BS would then provide the spatial filters to the CED once determine.
• the CED or a control node thereof de- termines the spatial filters in which the BS would provide the beam-splitting ratios to the CED or its control node to determine the spatial filters.
• the CED has been configured appropriately and the precoders of the BS have been determined, it is possible to transmit, on a shared block of time-frequency resources and towards the CED, transmit signals that include a superposition of signals for the paired UEs.
• a first component of the transmit signals has a first transmit polari- zation and a second component of the transmit signals has a second transmit polarization that is different than the first transmit polarization.
• the first component includes a mixture of the first signals and the second signals and the second component includes a further mixture of the first signals and the second signals (cf. Equation 3).
• assuming reciprocity it would be possible to receive such receive signals that include a superposition of signals from the paired UEs.
• SYP349050WO01 16 E39500WO SN FIG.10 is a signaling diagram of communication between the CED 109, the BS 101 and mul- tiple UEs 102, 105, 106 according to various examples.
• the BS 101 requests the UEs 102, 105, 106 to provide an indication indicated for of whether the respective UE includes a certain rank-1 receiver type, e.g., linear polarized or circular polarized.
• the UEs 102, 105, 106 provide the respective indication 4015 to the BS 101.
• 5010 and 5020 implement 3005 of the method of FIG.9.
• the BS 101 co-schedules pairs of UEs, so that – e.g. (cf. TAB.1: option III) – each pair includes a first rank-1 receiver type and a second rank-1 receiver type, e.g., linear polarized and circular polarized UEs. This corresponds to box 3015.
• the subsequent operation is illustrated in the signaling diagram of FIG.11.
• the BS 101 determines a transmit or receive beam di- rected towards the CED 109.
• each one of the UEs 102, 105 – here forming a pair 199 – determine respective transmit and receive beams towards the CED 109.
• the CED beams linking the BS 101 to the UE 102 and the BS 101 to the UE 105, re- spectively, are determined.
• the BS 101 can provide a configuration 4105 to the CED 109, wherein this configuration is indicative of the corresponding beams 671, 672, 679 (cf. FIG.7).
• the corresponding spatial filter can be applied at the CED 109.
• channel sounding signals 4110 can be communicated. This can include, e.g., downlink reference signals, for the different configurations of the CED 109 (pointing towards the UE 102 and pointing towards the UE 105, respectively); an uplink report provided by the UEs 102, 105 to the BS 101.
• the BS can then determine, at 5111, the precod- ing and the beam-splitting ratios (A-variables); this corresponds to box 3025.
• a further configuration 4115 can be provided to the CED 109.
• This configuration 4115 can be either indicative of the beam-splitting ratios so that the CED 109 can determine the appropriate spatial filters on its own; or the spatial filters can be predetermined and the BS 101 and then indicated to the CED 109 using the configuration 4115.
• the signals can be transmitted in time-frequency resources are shared channel such as the physical downlink shared channel the physical uplink shared channel.
• SYP349050WO01 17 E39500WO SN Although the invention has been shown and described with respect to certain preferred em- bodiments, equivalents and modifications will occur to others skilled in the art upon the read- ing and understanding of the specification. The present invention includes all such equiva- lents and modifications and is limited only by the scope of the appended claims.
• ANNEX I DETERMINING SPATIAL FILTER FOR BEAM SPLITTING We consider a CED with ⁇ elements and let ⁇ ⁇ ⁇ . Further, we assume beam splitting in two randomly selected directions drawn from a uniform power density function over the half sphere.
• ⁇ ⁇ and ⁇ ⁇ denote steering vectors in said two directions. If the CED has a rectangular shape, then the elements in the two steering vectors traverse the said rectangular shape in a particular order which is not relevant for subsequent derivations.
• the steering vector from the CED to the BS is denoted by ⁇ ⁇ .
• EXAMPLE1 A method of operating an access node (101) of a communications network, the access node (101) communicating wirelessly with a plurality of wireless communication devices (102, 105, 106) via a coverage enhancing device (109), wherein the method comprises: - requesting (3005), from each wireless communication device (102, 105, 106) of the SYP349050WO01 19 E39500WO SN plurality of wireless communication devices (102, 105, 106), a respective polarization indica- tion (4015) indicative of whether the respective wireless communication device (102, 105, 106) comprises a first rank-1 receiver (551) or transmitter type or a second rank-1 receiver (552) or transmitter type, the first rank-1 receiver or transmitter type being configured to re- ceive or transmit a linear polarization, the second rank-1 receiver or transmitter type being configured to receive or transmit a circular polarization.
• EXAMPLE 2 The method of EXAMPLE 1, wherein said requesting (3005) is triggered by a scheduling procedure for scheduling the plurality of wireless communication devices (102, 105, 106) to time-frequency resources of a downlink or uplink shared channel.
• EXAMPLE 3 The method of EXAMPLE 1 or 2, further comprising: - based on the polarization indications, co-scheduling (3015) pairs (199) of wireless communication devices (102, 105) of the plurality of wireless communication devices (102, 105, 106) to respective shared blocks of the time-frequency resources.
• each pair (199) comprises a respective first wireless communication device comprising the first rank-1 receiver or transmitter type and a second wireless communication device comprising the second rank-1 receiver or transmitter type.
• EXAMPLE 5 The method of EXAMPLE 3, wherein each pair (199) comprises a respective first wireless communication device comprising the second rank-1 receiver or transmitter type and a second wireless communica- tion device comprising the second rank-1 receiver or transmitter type.
• EXAMPLE 17 The method of any one of the preceding EXAMPLEs, further comprising: - requesting (3010), from each wireless communication device (102, 105, 106) of the plurality of wireless communication devices (102, 105, 106), a respective capability indication indicative of whether the respective wireless communication device (102, 105, 106) is capa- ble to switch between different rank-1 receiver (551, 552) or transmitter types.

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• 2023
  • 2023-10-05 WO PCT/EP2023/077609 patent/WO2024074630A1/en not_active Ceased
  • 2023-10-05 EP EP23789247.6A patent/EP4599524A1/de active Pending

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