Communication apparatus and method for communicating using transmit power differences between antennas

Abstract

A transceiver (570) can include a power amplifier (540). A first antenna port (520) can be coupled to the power amplifier to receive power from the power amplifier. A second antenna port (530) can be coupled to the power amplifier to receive power from the power amplifier. A controller (580) can determine transmit power difference information corresponding to a transmit power difference between a transmit power on the first antenna port and a transmit power on the second antenna port. The transceiver can transmit the transmit power difference information.

Description

Technical Field

[0001] This disclosure relates to methods and apparatus for communicating using the difference in transmit power between antennas. Background Technology

[0002] Currently, wireless communication devices such as User Equipment (UE) use wireless signals to communicate with other communication devices. For Time Division Duplex (TDD) bands, channel estimation for downlink channels, such as those from a base station (gNB) to the UE, can be based on Sounding Reference Signals (SRS) transmitted from the UE. Without SRS, the UE would need to measure the channel, select the best gNB precoder from a predefined codebook, and transmit the best precoder signal to the gNB. The advantage of SRS-based channel estimation is that the UE does not need to transmit the precoder signal to the gNB, and the gNB precoder is not limited to a predefined codebook. Unfortunately, there are problems with channel estimation based on SRS transmission. Attached Figure Description

[0003] To describe how the advantages and features of this disclosure can be obtained, the description of this disclosure is presented by reference to specific embodiments illustrated in the accompanying drawings. These drawings depict only exemplary embodiments of this disclosure and are therefore not to be considered as limiting its scope. The drawings may have been simplified for clarity and are not necessarily drawn to scale.

[0004] Figure 1 This is an example block diagram of a system according to a possible embodiment;

[0005] Figure 2 This is an example flowchart illustrating the operation of a device according to a possible embodiment;

[0006] Figure 3 This is an example flowchart illustrating the operation of a device according to a possible embodiment;

[0007] Figure 4 These are example diagrams of an apparatus according to possible embodiments; and

[0008] Figure 5 This is an example illustration of a system according to a possible embodiment. Detailed Implementation

[0009] The embodiments can provide a method and apparatus for communication over a wireless network. The embodiments can also provide a method and apparatus for communication using the difference in transmit power between antennas. The embodiments can further provide a communication apparatus and method for compensating for unequal SRS transmit power based on reciprocity-based channel estimation.

[0010] According to a possible embodiment, the transceiver may include a power amplifier. A first antenna port may be coupled to the power amplifier to receive power from the power amplifier. A second antenna port may be coupled to the power amplifier to receive power from the power amplifier. A controller may determine transmit power difference information corresponding to the transmit power difference between the transmit power at the first antenna port and the transmit power at the second antenna port. The transceiver may transmit this transmit power difference information.

[0011] Figure 1 This is an example block diagram of system 100 according to a possible embodiment. System 100 may include UE 110, at least one network entity 120 and 125, and network 130. UE 110 may be a wireless wide area network device, user equipment, wireless terminal, portable wireless communication device, smartphone, cellular phone, flip phone, personal digital assistant, smartwatch, personal computer, tablet computer, laptop computer, selective call receiver, IoT device, or any other user equipment capable of transmitting and receiving communication signals on a wireless network. At least one network entity 120 and 125 may be a wireless wide area network base station, may be a NodeB, may be an eNB, may be a gNB, such as a 5G NodeB, may be an unlicensed network base station, may be an access point, may be a base station controller, may be a network controller, may be a TRP, may be a network entity of a different type from other network entities, and / or may be any other network entity capable of providing wireless access between the UE and the network.

[0012] Network 130 can include any type of network capable of transmitting and receiving wireless communication signals. For example, network 130 can include wireless communication networks, cellular telephone networks, TDMA-based networks, CDMA-based networks, OFDMA-based networks, LTE networks, NR networks, 3GPP-based networks, 5G networks, satellite communication networks, high-altitude platform networks, the Internet, and / or other communication networks.

[0013] In operation, UE 110 can communicate with network 130 via at least one network entity 120. For example, UE 110 can send and receive control signals on the control channel and send and receive user data signals on the data channel.

[0014] There are some issues regarding channel estimation based on SRS transmission. The channel observed by the gNB is a series connection of the UE transmit RF circuitry, the propagation channel, and the gNB receive RF circuitry, where the RF circuitry filters and amplifies the signal and is located between the UE's digital-to-analog converter and its antenna, and between the gNB's antenna and its analog-to-digital converter. Similarly, the channel observed by the UE is a series connection of the gNB transmit RF circuitry, the propagation channel, and the UE receive RF circuitry, where the RF circuitry filters and amplifies the signal and is located between the gNB's digital-to-analog converter and its antenna, and between the UE's antenna and its analog-to-digital converter. If the gNB has M antennas and the UE has N antennas, then the propagation channel can be represented as an M x N matrix. Both the gNB transmit and receive RF circuitry can be represented as M x M matrices, and both the UE transmit and receive RF circuitry can be represented as N x N matrices. In this disclosure, it is assumed that the gNB is calibrated such that the gNB transmit and receive RF matrices are equal at least within a complex scaling factor.

[0015] Generally, below 6 GHz, the lack of UE RF calibration results in unequal transmit and receive RF matrices. At least, 3GPP specifications (e.g., TS 38.101-1) do not require UE RF calibration to make the transmit and receive RF equal.

[0016] Let H denote the M x N channel propagation matrix, where H includes the effects of the antenna patterns of the gNB and UE, as well as the orientation of the gNB and UE relative to each other and environmental factors such as the placement of hands and heads relative to the device. The singular value decomposition (SVD) of the channel matrix is ​​given by the following equation:

[0017] H = USV*

[0018] Where U is an M x M matrix whose columns are the left singular vectors of H, S is an M x N diagonal matrix whose diagonal values ​​are equal to the singular values ​​of H, V is an N x N matrix whose columns are equal to the right singular vectors, and * denotes the Hermitian property of the matrix. To achieve channel capacity, the gNB must know the left singular values ​​and their corresponding singular values ​​of H. The gNB does not require knowledge of the right singular vectors to achieve channel capacity.

[0019] For the UE, let T represent an NxN RF transmit channel and R represent an NxN RF receive channel. As noted above, T = R is not required in the RAN4 specification. In the absence of mutual coupling, both T and R are diagonal matrices. Now, consider the first case where the diagonal elements of T and R have the same amplitude but different phases, such that the following equation holds:

[0020]

[0021] In this case, the channel propagation matrix observed by the UE is given by the following equation:

[0022] HR

[0023] The matrix observed by gNB is as follows:

[0024]

[0025] Because the gNB observes the channel HT, it will calculate the SVD of HT and use the left singular vector and corresponding singular values ​​to select precoders and allocate power to these precoders. For precoding and power allocation to be correct for the UE, the left singular vector and corresponding singular values ​​should be the same for HT as for HR. Equivalently, it should hold that the left singular vector and singular values ​​are the same for HR as for the following equation:

[0026]

[0027] In fact, it can be proven that the left singular vector and singular value are the same for both matrices, and therefore, the base station can achieve optimized precoding and power allocation on the downlink even when HT≠HR.

[0028] We next consider the difference between the amplitude at the UE transmission and the amplitude at the UE reception. More specifically, we consider the case where the amplitude difference between different antennas is unequal, such that this difference cannot be modeled as a single complex gain difference shared by all antennas. In this case, we have

[0029]

[0030] Typically, |α1|≠|α2|≠|α3|. To ensure that these unequal gains have no impact on channel capacity, the left singular vector and singular value of HT should be equal to the left singular vector and singular value of HR, or equivalently, the left singular value and singular vector of HR should be equal to...

[0031]

[0032] However, it can be easily shown (by example) that the left singular vectors and singular values ​​of HT are not equal to those of HR, and therefore gNB will not be able to select precoders and power allocations among these precoders that are consistent with the channel capacity.

[0033] Now, it is clear from the RAN4 specification TS 38.101-1 that the UE transmit gain (within the multiplication constant) is not required to be equal to the UE receive gain. Specifically, in cases where some antenna ports are only for receiving in addition to SRS transmission, the TS 38.101-1 specification specifically defines transmit power relaxations applicable only to SRS symbols transmitted through these receive-only antenna ports, and these relaxations can be as large as 4.5 dB. The reason for these relaxations is that receive-only antenna ports do not have their own dedicated power amplifiers (PAs). Instead, the PAs used for SRS transmissions are borrowed from antenna ports designed for both data transmission and reception. Therefore, there are additional switching losses and trace losses between the PAs and the receive-only ports. The permitted relaxations are captured in the following text from TS 38.101-1.

[0034] When the SRS-TxSwitch capability is indicated such that the UE is configured with '1T2R', '1T4R', or '1T4R / 2T4R' of four SRS resources in the SRS resource set, the UE transmits SRS to ports other than the first SRS port; and when the SRS-TxSwitch capability is indicated such that the UE is configured with '2T4R' or '1T4R / 2T4R' of two SRS resources in the SRS resource set, the UE transmits SRS to ports other than the first or second SRS port, ΔT RxSRS Applied. ΔT RxSRS The value is 4.5 dB for n79 and for its F UL_high F below n79 UL_low The bandwidth is 3dB. For other SRS transmissions, ΔT RxSRS Zero;

[0035] The terms '1T2R', '1T4R', '2T4R', and '1T4R / 2T4R' can refer to different TxSwitch capabilities. For 1T2R, the UE has one transmit antenna and two receive antennas. For 1T4R, the UE has one transmit antenna and four receive antennas. For 2T4R, the UE has two transmit antennas and four receive antennas. For 1T4R / 2T4R, the UE has four receive antennas and can operate using one or two transmit antennas.

[0036] As can be seen, the permissible relaxation is 3dB for frequency bands below 4.5GHz and 4.5dB for frequency bands above 4.5GHz.

[0037] Currently, gNBs typically cannot determine SRS power relaxation (and compensation) for the RX-only port because the difference in received power from the UE antenna can be due to different sources. For example, the antenna pattern will be different for the transmit / receive antenna and the receive-only antenna. Additionally, the perceived gain will vary depending on the UE's orientation relative to the gNB. As another example, head / hand obstruction will differ for both transmit / receive antennas and the receive-only antenna due to the antenna's position on the device, and this difference will also depend on the usage scenario (voice, video, or gaming). As yet another example, the output power of the receive-only antenna can be significantly less than the output power of the transmit / receive antenna.

[0038] In the first and second examples, the differences in received power are correlated on both the uplink and downlink, and therefore do not need to be estimated or compensated. Conversely, the power differences in the third example are uncorrelated and therefore should be estimated and corrected in channel estimation to optimize downlink capacity.

[0039] While no known existing solution exists, one alternative could be to assume no transmit power relaxation for a receive-only antenna. Another option could be to assume relaxation for the maximum permissible transmit power for a receive-only antenna. Other disclosed embodiments can provide additional solutions to the problem.

[0040] For example, there could be additional methods by which the gNB can determine the difference in transmit power between the transmit / receive antennas and the receive-only antenna, wherein certain components may be shared and / or interchangeable among these methods. In a first method, the UE should be calibrated so that it can report the actual power slack on the receive antenna. Given this information, the gNB can correct its channel estimate. Using the corrected channel estimate, the gNB can correctly determine the optimized precoding vector from the left singular vector and can correctly determine the optimized power allocation from the singular vector.

[0041] The second method can also be used by the gNB to determine the difference in transmit power. In the first step, using the SRS transmitted by the UE, the gNB determines the difference in received power from the transmit / receive port and from the receive-only port. For a given gNB antenna port, the gNB initially measures the received power from the UE transmit / receive port and then measures the received power from the UE receive-only port. The gNB then calculates the difference between these two measured power values. The difference in received power reflects the UE antenna gain, hand / head obstruction, and transmit power relaxation.

[0042] In the second step, the UE measures the power received from the same gNB transmit port in the first step on both the transmit / receive port and the receive-only port. The UE then calculates the difference in received power. This difference reflects the difference between the UE antenna gain and head / hand obstruction, but does not include the UE transmit power slack between the two UE ports. The UE measurement can be performed on any set of reference symbols transmitted from the port used for the UE measurement in the first step.

[0043] In the third step, the measurement of the difference in received power between the two UE ports is reported to the gNB.

[0044] In the fourth step, the gNB determines the difference between the received power differences measured by the UE for the two UE ports with received power differences measured and reported by the UE. This difference reflects the transmit power relaxation performed by the UE on the receive-only port and should be used to correct the gNB channel estimation. The gNB should know which port is the transmit / receive port and which port is the receive-only port.

[0045] Steps one through four can be repeated for multiple gNB ports. The calculated estimate for each gNB port should be identical and can be averaged.

[0046] The embodiment provides a method to measure transmit power relaxation on the receive-only antenna (excluding SRS transmissions) by comparing the difference in uplink path loss between the UE transmit / receive antenna and the receive-only antenna at a single gNB antenna, and comparing this path loss difference with the difference in path loss measured at the UE between the transmit / receive antenna and the receive-only antenna received from the same gNB antenna. This difference is equal to the transmit power relaxation on the receive-only UE antenna. The difference in path loss measured at the UE from the gNB antenna to the transmit / receive antenna and the receive-only antenna is signaled to the gNB, enabling the gNB to calculate the transmit power relaxation on the receive-only antenna and use it to correct its SRS-based channel estimation.

[0047] The simulator can determine the capacity loss obtained when the gNB uses the measured channel without correcting for SRS power relaxation on the receive-only port, in order to select the optimal precoder and power allocation. The simulator will first determine the channel capacity based on the SNR of the actual channel. The simulator will then determine the measured channel based on the power relaxation on the receive-only antenna. The simulator will then calculate the precoder and power allocation for the measured channel and apply these to the actual channel. The capacity will be calculated under the assumption that the UE uses an MMSE receiver and the optimal coding rate is used (even if the gNB is unaware of the optimal coding rate).

[0048] Figure 2This is an example flowchart 200 illustrating the operation of a wireless communication device such as UE 110 according to a possible embodiment. At 210, transmit power difference information can be determined. The transmit power difference information can correspond to the transmit power difference between the transmit power at the first antenna port of the device and the transmit power at the second antenna port of the device. The second antenna port can be coupled to and use the same transmit power amplifier as the first antenna port.

[0049] An antenna port can include one or more antennas. A first antenna port can be considered both a transmit and receive antenna port, and a second antenna port can be considered a receive-only antenna port, except for selected signal transmissions. For example, some embodiments describe receive-only antennas and antenna ports to describe how certain antenna ports primarily used for receiving can transmit certain signals, like SRS, by sharing a power amplifier with the transmit and receive antennas or antenna ports. The concepts of "receive-only except for SRS," etc., are used for convenience only, and these antenna ports are considered any antenna port that shares the same PA with another antenna port but receives less power. Therefore, a receive-only antenna port can also be considered as described above under ΔT. RxSRS This applies to any antenna port. For example, such a port can receive less power from the PA because the electrical components between the PA and the receive-only antenna port are different from the electronic components between the PA and the transmit / receive antenna port. The different electronic components can be one or more of the following: a longer trace from the PA to the receive-only antenna port, at least one additional switch in the signal path, an additional filter, different or additional matching circuitry, and / or other elements capable of causing additional power loss. Furthermore, the PA can be physically farther from the receive-only antenna than from the transmit / receive antenna port, which can also cause different transmit power on different antenna ports when using the same setup for the PA. Additionally, the term power relaxation in this disclosure is based on allowing the UE to transmit at less maximum required power (such as relaxed power) on the receive-only antenna port than on the transmit / receive antenna port due to power loss between the PA and the receive-only antenna port. Embodiments can also be equally applied to two or more transmit / receive antenna ports, or any other number of antenna ports of any type, when antenna ports share the same PA and at least one antenna port receives less transmit power than the others due to different power loss between the PA and the antenna port. Earlier embodiments also described transmit power allowance relaxation, which corresponds at least to the lower maximum transmit power allowed for an antenna port that shares a power amplifier with another antenna port.

[0050] According to a possible embodiment, SRS transmission on the first antenna port can be switched when SRS transmission is performed on the second antenna port using a switch. The switch can be coupled between the first antenna port and the power amplifier, and also between the second antenna port and the power amplifier. The second antenna port can receive less power from the power amplifier when transmitting SRS than the first antenna port due to power losses between the power amplifier and the second antenna port. According to a possible embodiment, the first antenna port can be both a transmit and receive antenna port. The second antenna port can be an antenna port with a maximum output power for transmitting SRS that allows for a reduction in transmit power.

[0051] At 220, this transmit power difference information can be transmitted. According to a possible embodiment, the transmit power difference information can be the difference between the transmit power used for the SRS at the first antenna port and the transmit power used for the SRS at the second antenna port. The transmit power difference can also be relative to the transmit power difference of signals other than the SRS. In most embodiments, this difference can be expressed in dB, which is 10 times the logarithm of the ratio of the two powers. However, the difference can also be expressed as a ratio or in other units, such as dBm, watts, or other units.

[0052] According to a possible embodiment, a reference symbol can be received. A first received power of the reference symbol can be measured at a first antenna port. A second received power of the reference symbol can be measured at a second antenna port. The received power difference can be determined by subtracting the second received power from the first received power. The determined transmit power difference information can be the determined received power difference. For example, the transmit power difference information can correspond to the transmit power difference, and the received power difference can be combined with the received power difference measured by the gNB to determine the transmit power difference. Therefore, the transmit power difference information can include information about the received power difference. According to a possible embodiment, the measured received power can be converted to dB before subtracting them.

[0053] According to a possible implementation of the above embodiments, the received power difference can be a first received power difference. The third received power, as indicated by the reference symbol, can be measured at the third antenna port. The second received power difference can be determined by subtracting the third received power from the first received power. The second received power difference can be transmitted. This can correspond to situations where the power amplifier is shared by more than two antenna ports, such as in the 1T4R case described above.

[0054] According to another possible embodiment, a reference symbol can be received. A first received power of the reference symbol can be measured at a first antenna port. A second received power of the reference symbol can be measured at a second antenna port. The received power ratio of the second received power to the first received power can be determined. The determined transmit power difference information includes the determined received power ratio. The second received power ratio can also be determined using a measured third received power, similar to the second received power difference described above.

[0055] Figure 3 This is an example flowchart 300 illustrating the operation of a wireless communication device such as network entity 120 according to a possible embodiment. At 310, transmit power difference information can be received. The transmit power difference information can correspond to the transmit power difference between the transmit power at the first antenna port of the UE and the transmit power at the second antenna port of the UE. At 320, a channel estimate can be determined based on the received transmit power difference information.

[0056] According to a possible embodiment, receiving transmit power difference information can include receiving UE transmit power relaxation of the maximum output power of the SRS transmitted from the UE antenna port. Determining channel estimates can include forming channel estimates. Each channel estimate can be an estimate of the channel from the UE antenna port to each receive port of the network entity based on the SRS transmitted from the UE antenna port. The channel estimates can then be determined by scaling each of the formed channel estimates by the inverse of the transmit power relaxation of the UE antenna port.

[0057] According to a possible embodiment, the precoding vectors can be determined based on a scaled channel estimate. The determined precoding vectors can be left singular vectors. The power allocation for these precoding vectors can be determined by the singular values ​​determined from the scaled channel estimate.

[0058] According to a possible embodiment, a reference symbol can be transmitted from an antenna port of a network entity. A signal can be transmitted to instruct the UE to measure the received power using the transmitted reference symbol by performing a first measurement of received power at a first UE antenna port and a second measurement of received power at a second UE antenna port using the same power amplifier for transmission as the first antenna port. A signal can be transmitted to instruct the UE to determine and report the power difference obtained by subtracting the first measured received power at the second UE antenna port from the second measured received power at the first UE antenna port. The received transmit power difference information can be the determined power difference.

[0059] According to a possible implementation of the above embodiments, the determined power difference can be a UE power difference. SRS can be received from the UE. A first received power can be measured. The first received power can be the power of SRS transmitted from the first UE antenna port and received at the first antenna network entity antenna port. A second received power can be measured using SRS transmitted from the second UE antenna port using the same PA as the first antenna port and received at the first network entity antenna port. The network entity received power difference can be calculated by subtracting the power received from the first UE antenna port at the first network entity antenna port from the power received from the first UE antenna port at the first network entity antenna port.

[0060] According to a possible example of the above implementation, transmit power relaxation can be determined for the second UE antenna port by subtracting the network entity receive power difference from the UE power difference.

[0061] According to a possible implementation of the above example, the channel estimate can be formed based on each of the antenna ports from the second UE antenna port to the antenna ports of the network entity via SRS transmitted from the second UE antenna port. The channel estimate can be scaled by the inverse of a determined transmit power relaxation for the second UE antenna port.

[0062] According to a possible example of the above implementation, the precoder and power allocation are calculated based on a scaled channel estimate for transmitting data to the UE. Data can be transmitted to the UE based on the calculated precoder and power allocation. The method for estimating the transmit power difference between two UE antenna ports sharing the same PA can be implemented using network entities such as gNBs and antenna ports. The results can be identical, regardless of the gNB antenna port used to send reference symbols to the UE and measure the reference symbols received from the UE. Therefore, this method for estimating the transmit power difference between two UE antenna ports can be performed using multiple gNB antenna ports, after which the results can be averaged. This can further improve the estimation of the transmit power difference at the UE.

[0063] It should be understood that, although specific steps are shown in the figures, various additional or different steps can be performed depending on the embodiment, and one or more steps in a specific step can be rearranged, repeated, or completely eliminated depending on the embodiment. Furthermore, some of the performed steps can be repeated simultaneously on a continuous or ongoing basis while other steps are being performed. Additionally, different steps can be performed by different elements or in a single element of the disclosed embodiments. Moreover, network entities such as base stations, transmitting and receiving points, mobility management entities, or other network entities can perform interrelated operations of the UE. For example, a network entity can transmit signals received by the UE and can receive signals transmitted by the UE. The network entity can also process transmitted and received signals and operate on transmitted and received signals.

[0064] Figure 4 This is an example block diagram of apparatus 400 according to possible embodiments such as UE 110, network entity 120, or any other wireless communication device disclosed herein. Apparatus 400 may include housing 410, controller 420 coupled to housing 410, audio input and output circuitry 430 coupled to controller 420, display 440 coupled to controller 420, memory 450 coupled to controller 420, user interface 460 coupled to controller 420, transceiver 470 coupled to controller 420, at least one antenna port 475 such as at least one antenna coupled to transceiver 470, and network interface 480 coupled to controller 420. Apparatus 400 may not necessarily include all the elements illustrated for the different embodiments of this disclosure. Apparatus 400 is capable of performing the methods described in all embodiments.

[0065] Display 440 can be a viewfinder, LCD, LED display, OLED display, plasma display, projection display, touchscreen, or any other device for displaying information. Transceiver 470 can be one or more transceivers that include a transmitter and / or receiver. Audio input and output circuitry 430 can include a microphone, speaker, transducer, or any other audio input and output circuitry. User interface 460 can include a keypad, keyboard, buttons, touchpad, joystick, touchscreen display, another additional display, or any other device that provides an interface between the user and the electronic device. Network interface 480 can be a USB port, Ethernet port, infrared transmitter / receiver, IEEE 1394 port, wireless transceiver, WLAN transceiver, or any other interface that can connect the device to a network, device, and / or computer and transmit and receive data communication signals. Memory 450 can include RAM, ROM, EPROM, optical memory, solid-state memory, flash memory, removable memory, hard disk drive, cache, or any other memory that can be coupled to the device.

[0066] Device 400 or controller 420 can implement any operating system, such as Microsoft. Android TM Or any other operating system. For example, the device operating software can be written in any programming language such as C, C++, Java, or Visual Basic. The device software can also run on, for example, frame, The software and / or operating system can be stored in memory 450, elsewhere on device 400, in cloud storage, and / or anywhere else capable of storing the software and / or operating system. For example, the code for operation can be implemented as firmware programmed into ROM. Device 400 or controller 420 can also implement the disclosed operations using hardware. For example, controller 420 can be any programmable processor. Furthermore, controller 420 can perform some or all of the disclosed operations. For example, at least some operations can be performed using cloud computing and controller 420 can perform other operations. At least some operations can also be executed by computer-executable instructions executed by at least one computer processor. The disclosed embodiments can also be implemented on general-purpose or special-purpose computers, programmable microprocessors or microprocessors, proprietary integrated circuit elements, application-specific integrated circuits or other integrated circuits, hardware / electronic logic circuits such as discrete element circuits, programmable logic devices such as programmable logic arrays, field-programmable gate arrays, etc. Generally, controller 420 can be any controller or processor device or apparatus capable of operating the device and implementing the disclosed embodiments. Some or all of the additional elements of the device 400 may also perform some or all of the operations of the disclosed embodiments.

[0067] In operation, device 400 is capable of performing the methods and operations of the disclosed embodiments. Transceiver 470 is capable of transmitting and receiving signals, including data signals and control signals capable of including corresponding data and control information. Controller 420 is capable of generating and processing transmitted and received signals and information.

[0068] According to a possible embodiment described above, a method at the UE can include determining a power relaxation applied to a transmit antenna port that is a receive port other than the transmission of SRS symbols, and signaling the power relaxation of the UE antenna port to the gNB.

[0069] According to a possible related embodiment, a method at a gNB, wherein the gNB receives transmit power relaxation of SRS transmitted from a UE antenna port that is a receive port in addition to the transmission of SRS from the UE antenna port, can include forming an estimate of the channel from the UE receive port to each gNB receive port based on the SRS transmitted from the receive port, and scaling these channel estimates by the inverse of the transmit power relaxation of the UE receive port.

[0070] According to possible related embodiments, a method at the UE can include receiving a reference symbol from a gNB antenna port, measuring a first power received from the gNB antenna port at a first UE antenna port used for both data transmission and reception, measuring the power received from the gNB antenna port at a second UE antenna port used only for receiving data other than SRS transmission and using the same PA as the first antenna port, determining a received power difference at the gNB antenna port by subtracting a second received power from the first received power, and sending the power difference at the gNB antenna port to the gNB as a signal.

[0071] According to a possible implementation of the above embodiment in which the UE receives a reference symbol from the second gNB antenna port, the method can include measuring a first power received from the second gNB antenna port at a first UE antenna port used for both data transmission and reception, measuring the power received from the second gNB antenna port at a second UE antenna port that only receives data other than SRS transmission and uses the same PA as the first antenna port, determining the received power difference of the second gNB antenna port by subtracting the second received power from the first received power, and sending the power difference of the second gNB antenna port to the gNB as a signal.

[0072] According to possible related embodiments, a method at a gNB can include transmitting reference symbols from a gNB antenna port, signaling the UE to use these reference symbols to obtain a measurement of received power, wherein a first measurement is obtained at a first UE antenna port used for both data transmission and reception, and a second measurement is obtained at a second UE antenna port used only for receiving data other than SRS transmission and using the same PA as the first antenna port, and the UE is signaled to report the power difference obtained by subtracting the power received from the power received from the first UE antenna port from the power received from the second UE antenna port.

[0073] According to a possible implementation of the above embodiments, the method can include receiving a received power difference reported by the UE.

[0074] According to a possible example of the above implementation, the method can include measuring the power received on the gNB antenna port using SRS transmitted by the UE, measuring a first received power based on SRS transmitted from a first UE antenna port used for both data transmission and reception, measuring a second received power using SRS transmitted from a second UE antenna port that is only received in addition to SRS transmission and uses the same PA as the first antenna port, and calculating a power difference by subtracting the power received from the second UE antenna port from the power received from the first UE antenna port.

[0075] Figure 5This is an example diagram of system 500 according to a possible embodiment. System 500 may include wireless communication devices 510 and 550, such as wireless communication device 400. Wireless communication device 510 may be a UE, such as UE 110, and wireless communication device 520 may be a network entity, such as network entity 120. For simplicity, device 510 only shows controller 580, transceiver 570, and antenna ports 520 and 530 corresponding to the respective controller 420, transceiver 470, and antenna port 475 of device 400 when device 400 is a UE. Device 550 only shows antenna port 552 corresponding to antenna port 475 of device 400 when device 400 is a network entity. Any described antenna port may be one or more antennas.

[0076] Device 510 may include N antennas, including at least a first antenna 520 and a second antenna 530. The first antenna 520 may be both a transmit and receive antenna, and the second antenna 530 may be a receive-only antenna, except for certain transmissions such as SRS transmissions. Both antennas 520 and 530 may use the same transmit power amplifier 540 for transmission. Device 510 may include a transceiver 570, such as transceiver 470, and a controller 590, such as controller 420.

[0077] The first antenna 520 can be coupled to a switch 522 of the transceiver 570. Switch 522 can switch between coupling the first antenna 520 to a receiving circuit including a first receiving power amplifier 524 and coupling the first antenna 520 to a transmitting circuit including a transmitting power amplifier 540 and a switch 542 of the transceiver 570. The second antenna 530 can be coupled to a switch 532 of the transceiver 570. Switch 532 can switch between coupling the second antenna 530 to a receiving circuit including a second receiving power amplifier 534 and coupling the second antenna 530 to a transmitting circuit including a transmitting power amplifier 540 and a switch 542. Switch 542 can switch between which antenna 520 or 530 is coupled to the transmitting power amplifier 540. The UE 510 can also include an NxN RF transmit channel T 512 and an NxN RF receive channel R 514.

[0078] Device 550 can include a calibrated gNB antenna array comprising M antennas 552. The downlink channel 560 between device 550 and device 510 can be an M x N channel H. The uplink channel 565 between device 510 and device 520 can be an N x M channel that is a transpose of the downlink channel H.

[0079] In operation according to a possible embodiment, transceiver 570 may include power amplifier 540. A first antenna port 520 may be coupled to power amplifier 540 to receive power from power amplifier 540. A second antenna port 530 may be coupled to power amplifier 540 to receive power from power amplifier 540. A controller 580 may be coupled to transceiver 570. Controller 580 may determine transmit power difference information corresponding to the transmit power difference between the transmit power at the first antenna port 520 and the transmit power at the second antenna port 530. Transceiver 570 may transmit this transmit power difference information, such as via antenna ports 520 and / or 530.

[0080] Switch 542 can be coupled between the first antenna port 520 and the power amplifier 540. Switch 542 can also be coupled between the second antenna port 530 and the power amplifier 540. Controller 580 can control switch 542 to switch between transmitting SRS on the first antenna port 520 and transmitting SRS on the second antenna port 530. Due to power loss between the power amplifier 540 and the second antenna port 530, when transmitting SRS, the second antenna port 530 receives less power from the power amplifier 540 than the first antenna port 520.

[0081] According to a possible embodiment, the first antenna port 520 can be both a transmit and receive antenna port. The second antenna port 530 can be an antenna port with a permissible reduction in transmit power for its maximum output power used to transmit SRS. This permissible reduction in transmit power can take into account power loss between the power amplifier 540 and the second antenna port 530. According to a possible embodiment, the transmit power difference information can be the difference between the transmit power for SRS at the first antenna port 520 and the transmit power for SRS at the second antenna port 530.

[0082] Transceiver 570 can receive reference symbols via antenna ports 520 and 530. Controller 580 can measure a first received power of the reference symbol at the first antenna port 520. Controller 580 can measure a second received power of the reference symbol at the second antenna port 530. Controller 580 can determine the received power difference by subtracting the second received power from the first received power. The determined received power difference information can be the determined received power difference.

[0083] According to a possible embodiment, the received power difference can be a first received power difference. The controller 580 can measure a third received power of the reference symbol at a third antenna port (not shown). The controller 580 can determine a second received power difference by subtracting the third received power from the first received power. The transceiver 570 can transmit the second received power difference.

[0084] According to a possible embodiment, transceiver 570 is capable of receiving a reference symbol. Controller 580 is capable of measuring a first received power of the reference symbol at a first antenna port 520. Controller 580 is capable of measuring a second received power of the reference symbol at a second antenna port 530. Controller 580 is capable of determining a received power ratio between the second received power and the first received power. The determined transmit power difference information can be the determined received power ratio.

[0085] In order to illustrate the content already described in the above embodiments using equations, let G... f The forward channel from gNb (baseband) to UE (baseband) is represented by the following formula:

[0086] G f =HR

[0087] And G r The transpose of the reverse channel from UE (baseband) to gNb (baseband) is given by the following formula:

[0088]

[0089] G was measured using SRS and gNB. r =HT. To enable the gNB to select the optimal precoder and coding rate, it should calculate...

[0090]

[0091] in

[0092]

[0093] In the absence of mutual coupling in the UE, matrices T and R are diagonal matrices. gNB observation channel G r And it is necessary to determine the channel G. f In order to select the optimal pre-encoder and power distribution, and therefore a method is needed to measure the following matrices:

[0094]

[0095] The difference in transmit power between any two UE antennas i and j can be measured in the following way. Let G... f，k，i This represents the channel whose symbols are transmitted from the k-th gNB antenna and received at the i-th UE transmit antenna. To enable the UE to measure the forward channel from the k-th gNB, a reference signal is transmitted from the k-th base station antenna and received at the i-th UE antenna. The channel measured at the UE is... Given, where u k = [0, ..., 0, 1, 0, ..., 0] TIt is a vector of length M with a single "1" at the i-th position. If there is no mutual coupling in the UE receiver, then the signal received at the RF output for the i-th UE antenna is determined by H. k，i R i，i Given, and similarly, the signal received at the output of the j-th UE antenna is given by H. k，j R j，j Provided.

[0096] In order for gNB to measure the reverse channel G from the i-th UE antenna (including the UE RF) r The UE transmits a reference symbol from the i-th UE antenna. The channel measured at gNB is determined by G. r =HTv i Given, where v i = [0, ..., 0, 1, 0, ..., 0] T It is a vector of length N with a single "1" at the i-th position. If there is no mutual coupling in the UE transmitter, then the signal received at the output of the k-th gNB antenna is determined by H. k，i T i，i Given. Similarly, when a reference symbol is transmitted from the j-th UE antenna, the signal received at the output of the k-th gNB antenna is given by H. k，j T j，j Provided.

[0097] Based on these measurements, the UE reports the magnitude of the following ratios:

[0098]

[0099] Alternatively, the ratio, expressed in dB, can be given by the following formula:

[0100]

[0101] This ratio, or equivalent dB difference, can be transmitted from the UE to the gNB using a signal. Similarly, based on the gNB measurement results of the reference symbol transmitted at UE antenna ports i and j and measured at gNB antenna port k, the gNB can calculate the following ratio:

[0102]

[0103] Alternatively, the ratio, expressed in dB, can be given by the following formula:

[0104]

[0105] Knowing Δ R k，i，j and Δ Tk，i，j In both cases, the difference in gNB calculation

[0106] ΔR k，i，j -Δ T k，i，j

[0107] =10log10|H k，i R i，i |-10log10|H k，j R j，j |-(10log10|H k，i T i，i |-10log10|H k，j T j，j |)

[0108] =10log10|R i，i |-10log10|R j，j |-10log10|T i，i |+10lg10|T j，j |

[0109] =|α i |-|α j |

[0110] As pointed out in the discussion above, the difference |α i |-|α j |It is independent of the gNB's antenna port k and therefore any gNB antenna port can be used to transmit the reference symbol measured by the UE, as long as the same antenna port is used to measure the reference symbol transmitted by the UE.

[0111] Assume that UE antenna ports i and j share the same power amplifier, where antenna port i is used for both transmission and reception, and antenna port j is used only for reception except for SRS. If gNB knows |α i |,then|α j |Can be calculated as

[0112] |α i |-(Δ R k，i，j -Δ T k，i，j )=|α i |-(|α i |-|α j |)=|α j |

[0113] At least some of the methods disclosed herein can be implemented on a programmable processor. However, the controller, flowchart, and module can also be implemented on general-purpose or special-purpose computers, programmable microprocessors or microcontrollers and proprietary integrated circuit elements, integrated circuits, hardware electronic or logic circuits such as discrete element circuits, programmable logic devices, etc. Generally, any device residing thereon capable of implementing a finite state machine of the flowcharts shown in the figures can be used to implement the processor functions of this disclosure.

[0114] At least some embodiments improve the operation of the disclosed device. Furthermore, although this disclosure has been described using specific embodiments, it will be apparent to those skilled in the art that many alternatives, modifications, and variations will be readily apparent. For example, various components of the embodiments may be interchanged, added, or substituted in other embodiments. Moreover, not all elements in each figure are essential for the operation of the disclosed embodiments. For example, those skilled in the art will be able to utilize the teachings of this disclosure by simply employing the elements of the independent claims. Therefore, the embodiments of this disclosure as set forth herein are intended to be illustrative and not restrictive. Various changes may be made without departing from the spirit and scope of this disclosure.

[0115] In this document, relational terms such as “first,” “second,” etc., may be used only to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. Phrases following a list such as “at least one of,” “at least one selected from the group,” or “at least one selected from” are defined to mean one, some, or all, but not necessarily all, elements in the list. The terms “comprising,” “including,” “containing,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, product, or apparatus that includes the list of elements includes not only those elements but may include other elements not expressly listed or inherent to such a process, method, product, or apparatus. Elements preceded by “a,” “an,” etc., do not exclude the presence of additional identical elements in the process, method, product, or apparatus that includes that element, unless further constraints are imposed. Furthermore, the term “another” is defined as at least a second or more. Terms such as “containing,” “having,” etc., as used herein, are defined as “comprising.” In addition, the background section is not considered prior art, but is written as the inventor's own understanding of the context of some embodiments at the time of submission, and includes the inventor's own understanding of any questions regarding the prior art and / or problems experienced in the inventor's own work.

[0116] List of abbreviations

[0117] 3GPP Third Generation Partner Program

[0118] 5G (Fifth Generation)

[0119] ACK response

[0120] A-CSI (Aperiodic CSI)

[0121] BWP bandwidth portion

[0122] CC component carrier

[0123] CCCH SDU Common Control Channel Service Data Unit

[0124] CCE Control Channel Unit

[0125] CDMA Code Division Multiple Access

[0126] CRC Cyclic Redundancy Check

[0127] CRI CSI-RS Resource Index

[0128] C-RNTI Community RNTI

[0129] CSI-RS Channel State Information Reference Signal

[0130] CSI Channel State Information

[0131] CSS Public Search Space

[0132] DCI Downlink Control Information

[0133] DL downlink

[0134] DMRS demodulation reference signal

[0135] eNB Enhanced NodeB

[0136] gNB New Radio NodeB

[0137] HARQ-ACK Hybrid Automatic Repeat Request-Response

[0138] HST high-speed train

[0139] IoT (Internet of Things)

[0140] LTE Long Term Evolution

[0141] MAC CE Media Access Control Element

[0142] MCG Main Cell Group

[0143] MCS modulation and coding scheme

[0144] MPE Maximum Permissible Exposure

[0145] NACK (Negative Response)

[0146] NUL Non-Supplementary Uplink

[0147] NR New Radio

[0148] OFDMA (Orthogonal Frequency Division Multiplexing)

[0149] PA power amplifier

[0150] PCell main cell

[0151] PDCCH (Physical Downlink Control Channel)

[0152] PDSCH (Physical Downlink Shared Channel)

[0153] PDU Protocol Data Unit

[0154] PHR Power Headroom Report

[0155] P-MPR power management maximum power reduction

[0156] PRACH (Physical Random Access Channel)

[0157] PUCCH (Physical Uplink Control Channel)

[0158] PUSCH Physical Uplink Shared Channel

[0159] FDD (Frequency Division Duplex)

[0160] QCL Quasi-co-located

[0161] RAR Random Access Response

[0162] RLF wireless link failure

[0163] RNTI Temporary Identifier for Wireless Networks

[0164] RRM Wireless Resource Management

[0165] RS reference signal

[0166] RSRP reference signal received power

[0167] SAR specific absorption rate

[0168] SCell Auxiliary Community

[0169] SCG Auxiliary Community Group

[0170] SFI Slot Format Indicator

[0171] SFN Single Frequency Network

[0172] SpCell (Special Cell) (i.e., PCell for MCG or SCG)

[0173] SS / PBCH Synchronization Signal / Physical Broadcast Channel

[0174] SSBRI SS / PBCH Block Resource Index

[0175] SR scheduling request

[0176] SP-CSI Semi-Continuous CSI

[0177] SPS Semi-Persistent Scheduling

[0178] SRS Detection Reference Signal

[0179] SRI SRS resource indicator

[0180] SUL supplements uplink

[0181] TB transfer block

[0182] TCI Transport Configuration Indicator

[0183] TC-RNTI Temporary Cell RNTI

[0184] TDD (Time Division Duplex)

[0185] TDMA (Time Division Multiple Access)

[0186] UCI uplink control information

[0187] UE User Equipment

[0188] UL uplink

[0189] URLLC Ultra-Reliable Low-Latency Communication

[0190] TRP Transmit and Receive Points

[0191] USS UE-specific search space

Claims

1. A UE for wireless communication, comprising: A transceiver, the transceiver including a power amplifier; A first antenna port, the first antenna port being coupled to the power amplifier to receive power from the power amplifier; A second antenna port, which is coupled to the same power amplifier to receive power from the power amplifier; as well as A controller, coupled to the transceiver, wherein the controller determines transmit power difference information corresponding to the transmit power difference between the transmit power at the first antenna port and the transmit power at the second antenna port. The transceiver transmits the transmission power difference information. The second antenna port receives less power from the power amplifier when transmitting the probe reference signal than the first antenna port.

2. The UE of claim 1, further comprising a switch coupled between the first antenna port and the power amplifier and coupled between the second antenna port and the power amplifier. in, The controller controls the switch to switch between transmitting a probe reference signal on the first antenna port and transmitting a probe reference signal on the second antenna port.

3. The UE according to claim 1, wherein, The difference in transmit power corresponds to the fact that, due to power loss between the power amplifier and the second antenna port, the second antenna port receives less power from the power amplifier when transmitting the probe reference signal than the first antenna port.

4. The UE according to claim 1, in, The first antenna port includes transmit and receive antenna ports, and The second antenna port includes an antenna port having a permissible reduction in its maximum output power for transmitting a probe reference signal.

5. The UE according to claim 1, wherein, The transmit power difference information includes the transmit power difference between the transmit power of the probe reference signal used on the first antenna port and the transmit power of the probe reference signal used on the second antenna port.

6. The UE according to claim 1, in, The transceiver receives reference symbols, and Wherein, the controller The first received power of the reference symbol is measured at the first antenna port. The second received power of the reference symbol is measured at the second antenna port, and The received power difference is determined by subtracting the second received power from the first received power, wherein the determined transmitted power difference information includes the determined received power difference.

7. The UE according to claim 6, in, The received power difference includes a first received power difference, and Wherein, the controller The third received power of the reference symbol was measured at the third antenna port, and The second received power difference is determined by subtracting the third received power from the first received power, and The transceiver transmits the second received power difference.

8. The UE according to claim 1, in, The transceiver receives reference symbols, and Wherein, the controller The first received power of the reference symbol is measured at the first antenna port. The second received power of the reference symbol is measured at the second antenna port, and Determine the receive power ratio between the second receive power and the first receive power, wherein the determined transmit power difference information includes the determined receive power ratio.

9. The UE according to claim 1, wherein, The first antenna port includes a first antenna and the second antenna port includes a second antenna.

10. A method in a communication device, the method comprising: At the communication device, transmit power difference information corresponding to the transmit power difference between the transmit power at the first antenna port of the communication device and the transmit power at the second antenna port of the device is determined, wherein the second antenna port is coupled to and uses the same transmit power amplifier as the first antenna port; and Transmit the transmission power difference information. The second antenna port receives less power from the power amplifier when transmitting the probe reference signal than the first antenna port.

11. The method of claim 10, further comprising switching between transmitting a probe reference signal at the first antenna port and transmitting a probe reference signal at the second antenna port using a switch, wherein, The switch is coupled between the first antenna port and the power amplifier, and is also coupled between the second antenna port and the power amplifier.

12. The method according to claim 10, wherein, The difference in transmit power corresponds to the fact that, due to power loss between the power amplifier and the second antenna port, the second antenna port receives less power from the power amplifier when transmitting the probe reference signal than the first antenna port.

13. The method according to claim 10, in, The first antenna port includes transmit and receive antenna ports, and The second antenna port includes an antenna port having a permissible reduction in its maximum output power for transmitting a probe reference signal.

14. The method of claim 10, wherein, The transmit power difference information includes the transmit power difference between the transmit power of the probe reference signal used on the first antenna port and the transmit power of the probe reference signal used on the second antenna port.

15. The method of claim 10, further comprising: Receive reference symbol; Measure the first received power of the reference symbol at the first antenna port; The second received power of the reference symbol is measured at the second antenna port; as well as The received power difference is determined by subtracting the second received power from the first received power, wherein the determined transmitted power difference information includes the determined received power difference.

16. The method according to claim 15, in, The received power difference includes a first received power difference, and The method further includes: The third received power of the reference symbol is measured at the third antenna port; The second received power difference is determined by subtracting the third received power from the first received power; and Transmit the second received power difference.

17. The method of claim 10, further comprising: Receive reference symbol; Measure the first received power of the reference symbol at the first antenna port; The second received power of the reference symbol is measured at the second antenna port; as well as Determine the receive power ratio between the second receive power and the first receive power, wherein the determined transmit power difference information includes the determined receive power ratio.

18. The method according to claim 10, wherein, The first antenna port includes a first antenna and the second antenna port includes a second antenna.

19. A processor for wireless communication, comprising: At least one controller, coupled to at least one memory, and configured to cause the processor to: Determine transmit power difference information corresponding to the transmit power difference between the transmit power at the first antenna port of the device and the transmit power at the second antenna port of the device, wherein the second antenna port is coupled to and uses the same transmit power amplifier as the first antenna port; and Transmit the transmission power difference information. The second antenna port receives less power from the power amplifier when transmitting the probe reference signal than the first antenna port.

20. The processor of claim 19, wherein, The difference in transmit power corresponds to the fact that, due to power loss between the power amplifier and the second antenna port, the second antenna port receives less power from the power amplifier when transmitting the probe reference signal than the first antenna port.

Images