Management of power amplifiers

Abstract

Embodiments of the present disclosure relate to management of power amplifiers. An apparatus includes: a plurality of power amplifiers, wherein at least some of the plurality of power amplifiers have different maximum output power capabilities; a plurality of antenna ports; and a control component configured to select a set of one or more power amplifiers from the plurality of power amplifiers for simultaneous transmissions via the respective antenna ports.

Description

Technical Field

[0001] Examples of the present disclosure relate to management of power amplifiers. Background Art

[0002] Power amplifiers are used in radio communications to send radio signals.

[0003] The power amplifier is coupled to the antenna element via the antenna port.

[0004] When a power amplifier is operated backed off from its maximum output power capability, its efficiency can be significantly reduced. Summary of the invention

[0005] According to various but not necessarily all examples, there is provided an apparatus comprising:

[0006] a plurality of power amplifiers, wherein at least some of the plurality of power amplifiers have different maximum output power capabilities;

[0007] Multiple antenna ports;

[0008] A control component is configured to select a set of one or more power amplifiers from a plurality of power amplifiers for simultaneous transmission via corresponding antenna ports.

[0009] In some but not necessarily all examples, the control component is configured to control a combined total transmit power of the set of one or more power amplifiers to be less than or equal to a combined total transmit power target.

[0010] In some but not necessarily all examples, the control component is configured to select a set of power amplifiers such that the power amplifiers in the set have different maximum output power capabilities.

[0011] In some but not necessarily all examples, the control component is configured to select a set of power amplifiers such that the power amplifiers in the set have a lowest maximum output power capability sufficient to enable a combined total transmit power of the set of one or more power amplifiers to meet a combined total transmit power target.

[0012] In some but not necessarily all examples, the control component is configured to evenly distribute a combined total transmit power of a set of one or more power amplifiers across a set of one or more power amplifiers, wherein the power amplifiers in the set are controlled to have the same power output simultaneously.

[0013] In some but not necessarily all examples, the control component is configured to select a set of one or more power amplifiers from a plurality of power amplifiers for simultaneous transmission via corresponding antenna ports, and to distribute a combined total transmit power of the set of one or more power amplifiers across the set of one or more power amplifiers, reducing or minimizing a backoff from maximum output power capabilities of the power amplifiers to achieve distribution of a maximum total transmit power target across a required number of power amplifiers.

[0014] In some but not necessarily all examples, a combined total transmit power of a set of one or more power amplifiers is determined at respective antenna ports and includes an estimate of a path loss between each power amplifier in the set of one or more power amplifiers and its respective antenna port.

[0015] In some but not necessarily all examples, the control component is configured to replace a power amplifier in a set of one or more power amplifiers in response to a request to increase the combined total transmit power of the set only when the output power of the power amplifier for replacement has reached its maximum output power capability.

[0016] In some but not necessarily all examples, the control component is configured to select an additional power amplifier from remaining power amplifiers of the plurality of power amplifiers that are not currently in the set to add to the set of one or more power amplifiers, wherein the selected additional power amplifier is a power amplifier among the remaining power amplifiers having a lowest maximum output power capability.

[0017] In some but not necessarily all examples, the control component is configured to select an antenna port for each power amplifier in a set of one or more power amplifiers based on an estimate of power loss in a transmission channel associated with the antenna port and / or an estimate of power loss in a path between a power amplifier in the set of one or more power amplifiers and a corresponding selectable antenna port.

[0018] In some but not necessarily all examples, the control component is configured to select, for a power amplifier of the primary carrier, an antenna port having a best estimate of power loss in a transmission channel associated with the antenna port.

[0019] In some but not necessarily all examples, the control component is configured to control a switching arrangement between multiple power amplifiers and multiple antenna ports, wherein the switching arrangement is configured to connect each of the multiple power amplifiers to at least one antenna port and to connect at least a first one of the multiple power amplifiers to any one of a plurality of different antenna ports among the multiple antenna ports, wherein the first one of the multiple power amplifiers has a highest maximum output power capability among the multiple power amplifiers.

[0020] In some but not necessarily all examples, the control component is configured to switch a power amplifier having the highest maximum output power capability among a plurality of power amplifiers to any one of a first number of antenna ports among a plurality of antenna ports, and to switch a power amplifier having the lowest maximum output power capability among a plurality of power amplifiers to any one of a second number of antenna ports among a plurality of antenna ports, wherein the first number is a maximum number of antenna ports to which any of the plurality of power amplifiers can be switched, and the second number is a minimum number of antenna ports to which any of the plurality of power amplifiers can be switched.

[0021] In some but not necessarily all examples, the apparatus includes a plurality of antennas, wherein each of the plurality of antennas is coupled to one of a plurality of antenna ports for at least transmission.

[0022] In some but not necessarily all examples, the apparatus is comprised in a user equipment configured for communication with a cellular telecommunications network, wherein one or more of the plurality of power amplifiers are configurable for simultaneous uplink transmissions to the cellular telecommunications network.

[0023] In some but not necessarily all examples, one of the plurality of power amplifiers itself meets a maximum output power requirement controllable by the cellular telecommunications network via downlink control signaling.

[0024] According to various but not necessarily all examples, there is provided a method comprising:

[0025] A set of one or more power amplifiers is selected from a plurality of power amplifiers for simultaneous transmission via corresponding antenna ports, wherein at least some of the plurality of power amplifiers have different maximum output power capabilities.

[0026] According to various but not necessarily all examples, a computer program is provided that includes instructions that, when executed by one or more processors, cause: selecting a set of one or more power amplifiers from a plurality of power amplifiers for simultaneous transmission via corresponding antenna ports, wherein at least some of the plurality of power amplifiers have different maximum output power capabilities.

[0027] Examples are provided as claimed in the following claims according to various but not necessarily all examples.

[0028] Although the above examples and optional features of the present disclosure are described separately, it should be understood that all possible combinations and arrangements of them are included in the present disclosure. It should be understood that various examples of the present disclosure may include any or all features described with respect to other examples of the present disclosure, and vice versa. In addition, it should be understood that any one or more or all of these features may be implemented / included in / executable by devices, methods and / or computer program instructions in any combination, as needed and as appropriate. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Some examples will now be described with reference to the accompanying drawings, in which:

[0030] Figure 1 An example of the subject matter described herein is shown;

[0031] Figure 2 Another example of the subject matter described herein is shown;

[0032] Figure 3A Another example of the subject matter described herein is shown;

[0033] Figure 3B Another example of the subject matter described herein is shown;

[0034] Figure 4 Another example of the subject matter described herein is shown;

[0035] Figure 5 Another example of the subject matter described herein is shown;

[0036] 6A to 6F An example of the subject matter described herein is shown;

[0037] Fig. 7A and Figure 7B Other examples of the subject matter described herein are shown;

[0038] Figure 8 Another example of the subject matter described herein is shown;

[0039] Fig. 9Another example of the subject matter described herein is shown;

[0040] Fig.10 Another example of the subject matter described herein is shown;

[0041] Fig.11 Another example of the subject matter described herein is shown;

[0042] Fig.12 Another example of the subject matter described herein is shown; and

[0043] Fig.13 Another example of the subject matter described herein is shown.

[0044] The drawings are not necessarily to scale. For clarity and brevity, certain features and views of the drawings may be shown schematically or in scale. For example, the dimensions of some elements in the drawings may be exaggerated relative to other elements for ease of explanation. Similar reference numerals are used in the drawings to indicate similar features. For clarity, not all reference numerals must be shown in all drawings.

[0045] In the following description, a class (or collection) may be referred to using a reference numeral without a subscript index (e.g., 20), a specific instance of a class (a member of a collection) may be referred to using a reference numeral with a numeric subscript index (e.g., 20_1), and a non-specific instance of a class (a member of a collection) may be referred to using a reference numeral with a variable subscript index (e.g., 20_i). DETAILED DESCRIPTION

[0046] The following description describes an example of an apparatus 10 comprising: a plurality of power amplifiers 20_i, wherein at least some of the plurality of power amplifiers 20_i have different maximum output power capabilities 22_i; a plurality of antenna ports 30_j; and a control component 40 configured to select a set 60 of one or more power amplifiers 20_i from the plurality of power amplifiers 20_i for simultaneous transmission via corresponding one or more antenna ports 30_j.

[0047] Figure 1 An example of an apparatus 10 is illustrated, the apparatus comprising: a plurality of power amplifiers 20_i, a plurality of antenna ports 30_j; and a controller 40 configured to select a set 60 (of one or more power amplifiers 20_i) from the plurality of power amplifiers 20_i for simultaneous transmission via corresponding antenna ports 30_j. Figure 1 At least some of the plurality of power amplifiers 20_i have different maximum output power capabilities 22_i.

[0048] PAs of different specifications can be purchased off the shelf from component manufacturers. Thus, a first power amplifier can be purchased as a component with a maximum output power of 24 dBm, for example, for a given set of bias / operating conditions, and a second power amplifier can be purchased as a component with a maximum output power of 19 dBm, for example, for a given set of bias / operating conditions. The second power amplifier cannot provide an output power level of 24 dBm, but the first PA can provide an output power level of 19 dBm by being controlled ("biased" or "backed off") to operate at a lower output power level (although with changed efficiency).

[0049] In this example, there are M antenna ports 30_j and N power amplifiers 20_i. In some but not necessarily all examples, M and N are different. In some but not necessarily all examples, M and N are equal. Each power amplifier 20_i has an associated maximum output power capability 22_i. This is the maximum power level P_i at which the power amplifier 20_i can be operated by the device 10.

[0050] In the example shown, the controller 40 couples the power amplifier 20_i to the antenna port 30_j for transmission via the antenna port 30_j. The coupling is via a path 42_ij.

[0051] In this example, the controller 40 is configured to couple one power amplifier 20_i to one antenna port 30_j and one antenna port 30_j to one power amplifier 20_i via one path 42_ij.

[0052] Figure 2 It is illustrated that in at least some examples, the apparatus 10 described above may include or be enhanced with an antenna element 50. Each antenna port 30_j is coupled to a respective antenna element 50_j, and each antenna element 50_j is coupled to its respective antenna port 30_j.

[0053] In some but not necessarily all examples, the apparatus 10 is a module for a user equipment. Such a module may include the antenna element 50. Alternatively, the antenna element 50 may be connected to the module.

[0054] In some, but not necessarily all, examples, the apparatus 10 is, or is comprised in, a user equipment, wherein the antenna ports 30_i are connected to respective antenna elements 50_i.

[0055] In some but not necessarily all examples, the power amplifier 20 and supporting circuitry are disposed on a printed circuit board (PCB) of the user device. For example, the antenna element 50 may be disposed elsewhere in the user device (e.g., attached to the inner surface of a cover of the user device) and connected to the antenna port 30 residing on the PCB.

[0056] For example, the set 60 of power amplifiers 20_x may have M components, each selectively coupled to only one of the M antenna ports 30_y (or antenna elements 50). Each of the antenna ports 30_y is permanently connected to an antenna element 50_y.

[0057] In at least some examples, the user equipment is configured for communication with a cellular telecommunication network.The set 60 of power amplifiers 20_i may be configured for simultaneous uplink transmission (UL Tx) to the cellular telecommunication network.

[0058] For example, by providing multiple alternative UL Tx channels, multiple simultaneous UL Tx can be used to improve the robustness of communications.

[0059] For example, by providing multiple parallel UL Tx channels, multiple simultaneous UL Tx can be used to increase the communication bandwidth.

[0060] For example, multiple simultaneous UL Tx may be used for carrier aggregation (CA) and / or dual connectivity (DC) and / or UL Tx diversity.

[0061] For example, multiple simultaneous UL Tx can be used for Multiple Input Multiple Output (MIMO) operation. This uses the same frequency band for all UL Tx.

[0062] In some but not necessarily all examples, UL Tx occurs in a frequency range between 7 and 24 GHz. Antenna element 50 may be optimized for use within the same operating bandwidth within this frequency range.

[0063] Figure 3A and Figure 3B The operation of the above-described apparatus 10 is illustrated. The controller 40 selects a set 60 of one or more power amplifiers 20_i from the plurality of power amplifiers 20_i for simultaneous transmission via corresponding antenna ports 30_j.

[0064] Each power amplifier 20_i has an associated maximum output power capability 22_i. This is the maximum power level P_i at which the power amplifier 20_i can be operated by the device 10.

[0065] Each power amplifier 20_i in the set 60 operates at a power p_i (operating power 24_i). The difference between the maximum power level P_i and the operating power level p_i of the power amplifier 20_i is the back-off 28_i.

[0066] Typically, the controller 40 couples a power amplifier 20_i to an antenna port 30_j via a path 42_ij. The power amplifier 20_i has an associated maximum output power capability 22_i and operates with a back-off 28_i that provides an operating power 24_2. The path 42_ij may have an associated path loss L_ij. The operating output power 26_j at the antenna port 30_j has a level p*_ij equal to p_ij-L_ij.

[0067] exist Figure 3A In the example shown, the controller 40 couples the power amplifier 20_2 to the antenna port 30_1 via the path 42_21. The power amplifier 20_2 operates at a back-off 28_2 from its maximum power level P_2 and has an operating power 24_2 (p_2). This produces an operating output power 26_2 (p*21) at the antenna port 30_1.

[0068] The controller 40 couples the power amplifier 20_3 to the antenna port 30_3 via the path 42_33. The power amplifier 20_3 operates at a back-off 28_3 from its maximum power level P_3 and has an operating power 24_3 (p_3). This produces an operating output power 26_3 (p*_33) at the antenna port 30_3.

[0069] The controller 40 couples the power amplifier 20_4 to the antenna port 30_4 via the path 42_44. The power amplifier 20_4 operates at a back-off 28_4 from its maximum power level P_4 and has an operating power 24_4 (p_4). This produces an operating output power 26_4 (p*_44) at the antenna port 30_4.

[0070] In this example, the power amplifier 20_1 is not used. In this example, the antenna port 30_2 is not used. The set 60 comprises the power amplifiers 20_2, 20_3, 20_4. The associated set 62 of antenna ports 30 comprises the antenna ports 30_1, 30_3, 30_4.

[0071] exist Figure 3B In the example shown, the controller 40 couples the power amplifier 20_1 to the antenna port 30_2 via the path 42_12. The power amplifier 20_1 operates at a back-off 28_1 from the maximum power level P_1 and has an operating power 24_1 (p_1). This produces an operating output power 26_2 (p*_12) at the antenna port 30_2.

[0072] The controller 40 couples the power amplifier 20_2 to the antenna port 30_3 via the path 42_23. The power amplifier 20_2 operates at a back-off 28_2 from the maximum power level P_2 and has an operating power 24_2 (p_2). This produces an operating output power 26_3 (p*_23) at the antenna port 30_3.

[0073] The controller 40 couples the power amplifier 20_3 to the antenna port 30_4 via the path 42_34. The power amplifier 20_3 operates at a back-off 28_3 from the maximum power level P_3 and has an operating power 24_3 (p_3). This produces an operating output power 26_4 (p*_34) at the antenna port 30_4.

[0074] In this example, the power amplifier 20_4 is not used. In this example, the antenna port 30_1 is not used. The set 60 comprises the power amplifiers 20_1, 20_2, 20_3. The associated set 62 of antenna ports 30 comprises the antenna ports 30_2, 30_3, 30_4.

[0075] refer to Figure 1 , Figure 2 , Figure 3A and Figure 3B It may be desirable to use the controller 40 to avoid using a certain antenna port 30_1 due to path loss in the transmission channel associated with that antenna port 30_1. This may be caused by local interference to a particular antenna 50, for example.

[0076] It may be desirable to use the controller 40 to avoid using certain power amplifiers 20 to reduce power consumption and / or improve operating efficiency. This may be achieved by the controller 40 controlling which power amplifiers 20_i are coupled to which antenna ports 30_j.

[0077] It may be desirable to use the controller 40 to control the use of certain power amplifiers 20 to reduce power consumption and / or improve operating efficiency. This can be achieved by controlling the back-off 28_i of the selected power amplifiers. Since the power amplifiers 20_i can have different maximum output power capabilities, the back-off can also depend on the selection of the set 60 of power amplifiers 20_i by the controller 40.

[0078] The controller 40 (controller) is configured to control a combined total transmit power of a set 60 of one or more power amplifiers 20_i to be less than or equal to a combined total transmit power target (T).

[0079] The combined total transmit power target (T) may be, for example, a target based on a maximum transmit power limit Pmax that may be specified by the network. For example, the network may use a defined number of different user equipment power classes. The UE power class defines the maximum UL transmit power of the UE 10 over the channel bandwidth. The power class may vary with the UL Tx frequency. Currently, power class 2 has a maximum output power of 26 dBm (+2 / -3 dB) and power class 3 has a maximum output power of 23 dBm (+2 / -2 to -3 dB).

[0080] The power level used by the UE 10 may be based on a network command. In some examples, the power level used may be based on a percentage of uplink symbols relative to the UE, or a specific threshold, or a fixed 50% threshold.

[0081] In the following examples, the power amplifiers 20_i in the selected set 60 are controlled to have the same target. In some examples, a target can be set for a combination of operating powers 24_i (p_i). That is, p_i is the same for all power amplifiers in the set 60. In some examples, a target can be set for a combination of operating output powers 26_3 (p*) at the antenna port 30_3. That is, p_i* is the same for all power amplifiers 20_i in the set 60. If the loss (e.g., path loss L_ij) is constant or ignored, the former is the same as the latter.

[0082] Therefore, without loss of generality, it may be assumed that the operating output power 26_3 (level p*_ij) is the same for all power amplifiers 20_i in the set.

[0083] If there are m antenna ports and the total transmit power target is T, then the target power of each power amplifier 24_i in the set is t=T / m.

[0084] The power amplifier 20_i is connected to the antenna port 30_j via a path 42_ij. The path 42_ij has a path loss L_ij. The operating power 24_i is p_i and the operating output power 26_j is p*_ij, where p_i=p*_ij+L_ij=t+L_ij.

[0085] The controller 40 selects m pairs (i, j) (where there are m different i's and m different j's).

[0086] The selection may be based on different optimization algorithms or combinations of optimization algorithms. The selection may be based on different constraints.

[0087] For example, one constraint is that the operating power p_i of the power amplifier 20_i must be less than or equal to the maximum output power capability (P_i) of the power amplifier 20_i in order for the power amplifier 20_i to be in the set 60. The power amplifier 20_i must have sufficient output power capability.

[0088] For example, in some examples, the back-off 28 is minimized, such as minimizing the difference between the maximum output power capability (P_i) of the power amplifier 20_i and the operating power p_i of the same power amplifier 20_i.

[0089] The minimization may, for example, minimize the sum of the back-offs 28 over the set 60 (minimize the mean), and / or the minimization may, for example, minimize the median over the set 60. This may encourage the use of the power amplifier 20 with the lowest operable maximum output power capability P_i.

[0090] The controller 40 may, for example, select power amplifiers 20_i for the set 60 to reduce or minimize the sum of the differences between the operating powers (p_i) of the power amplifiers 20_i in the set 60 and the maximum output power capabilities 22_i of the respective power amplifiers 20_i.

[0091] The controller 40 may, for example, select power amplifiers 20_i for the set 60 to reduce or minimize a maximum difference between an operating power of a power amplifier 20_i in the set 60 and a maximum output power capability 22_i of the respective power amplifier 20_i.

[0092] You may wish to restrict which antennas are used.

[0093] For example, it may be desirable to restrict a particular power amplifier 20 to use only a particular antenna 50, either permanently or variably, for example depending on uplink transmission channel losses of different antenna elements.

[0094] For example, it may be desirable to restrict the use of certain power amplifiers 20 to only those whose maximum output power capability P_i is above a minimum value.

[0095] For example, it may be desirable to restrict the use to only those specific power amplifiers whose maximum output power capability P_i is below a maximum value.

[0096] For example, it may be desirable to constrain the specific paths available between a power amplifier and an antenna port based on the power loss L_ij of the path 42_ij.

[0097] If we assume that power amplifier 20_1 has a maximum output power capability P_1. In some examples, it may be desirable to be able to meet the combined total transmit power target (T) using only power amplifier 20_1. In this example, P_1 =T.

[0098] It may also be desirable to be able to use both power amplifier 20_1 and power amplifier 20_2 to meet the combined total transmit power target (T). Thus, operation of power amplifier 20_1 at output power P_2 and operation of power amplifier 20_2 at its maximum capability P_2 provide an output power 2P_2 equal to the transmit power target (T). In dBm, 10log(T)=10log(P_2+P_2)=10logP_2+10log2&10logP_2=10log(T)-10log2.

[0099] It may also be desirable to be able to use power amplifier 20_1, power amplifier 20_2, and power amplifier 20_3 to meet the combined total transmit power target (T). Therefore, the operation of power amplifier 20_1 at output power P_3, the operation of power amplifier 20_2 at output power P3, and the operation of power amplifier 20_3 at maximum capability P3 provide an output power 3P_3 equal to the transmit power target (T). In dBm, 10log(T)=10log(3*P_3)=10logP_2+10log3&10logP_3=10log(T)-10log3.

[0100] Therefore, it can be understood that in at least some examples, the controller 40 is configured to select a set 60 of power amplifiers 20_i so that the power amplifiers 20_i in the set 60 have different maximum output power capabilities 22_i. The control component 40 can be configured to select a set 60 of power amplifiers 20_i so that the power amplifiers 20_i in the set 60 have a minimum maximum output power capability 22_i sufficient to enable the combined total transmit power of the set 60 of one or more power amplifiers 20_i to meet the combined total transmit power target.

[0101] In at least some examples, the power amplifiers 20 have a PAE (power added efficiency) peak at a maximum output power defined by their maximum output power capability P_i. An increase in the back-off 28_i of the power amplifier 20_i reduces its power added efficiency. The selection of the set 60 of power amplifiers 20_i can be based on a reduction or optimization (e.g., minimization) of a cost function based on the difference between the operating power (p_i) of the power amplifier 20_i at the power amplifier 20_i and the maximum output power capability 22_i (P_i) of the corresponding power amplifier 20_i, wherein the selection of the set 60 of power amplifiers 20_i optimizes the cost function. The cost function can also take into account path loss.

[0102] In at least some examples, controller 40 is configured to evenly distribute a combined total transmit power of a set 60 of one or more power amplifiers 20_i across a set 60 of one or more power amplifiers 20_i, where the power amplifiers 20_i in set 60 are controlled to have the same power output simultaneously.

[0103] In at least some examples, the controller 40 is configured to select a set 60 of one or more power amplifiers 20_i from a plurality of power amplifiers 20_i for simultaneous transmission via corresponding antenna ports 30_j, and to allocate a combined total transmit power of the set 60 of one or more power amplifiers 20_i across the set 60 of one or more power amplifiers 20_i, reducing or minimizing a backoff 28 from a maximum output power capability 22_i of the power amplifier 20_i to achieve allocation of a maximum total transmit power target (T) across a required number (m) of power amplifiers 20_i.

[0104] The combined total transmit power of the set 60 of one or more power amplifiers 20_i is determined at the corresponding antenna port 30_j and includes an estimate of the path loss L_ij between each power amplifier 20_i in the set 60 of one or more power amplifiers 20_i and its corresponding antenna port 30_j. The estimate of the path loss L_ij may be the same for all paths or may be a calibrated value, wherein the calibrated value contains information about the loss L_ij.

[0105] The apparatus 10 may calibrate for each power amplifier 20_i at an antenna port 30_j having insertion loss, while additionally measuring the incremental power of each power amplifier 20_i at other configurable antenna ports 30_j to which the power amplifier output may be routed.

[0106] Calibration of the power loss L_ij based on the path 42_ij may be performed on a per antenna port 30_j basis.

[0107] Calibration based on the power loss L_ij of the path 42_ij may be performed on a per power amplifier 20_i basis.

[0108] The calibration based on the power loss L_ij of the path 42_ij may be performed on a per frequency band basis, or on a per frequency step basis to correct for higher errors.

[0109] In at least some examples, the controller 40 is configured to assign the power amplifiers 20_i to the respective antenna ports 30_j such that the power amplifier 20_i in the set 60 having the relatively highest maximum output power capability 22_i is assigned to the antenna port 30_j in the set 60 having the relatively largest estimated path loss. This reduces the back-off 28_i because the compensation for the path loss increases the operating power level p_i, thereby reducing the back-off 28_i.

[0110] In some examples, the concept of power loss may be extended to the radio transmission channel. For example, the radio transmission channel power loss associated with antenna 50_j may be added to the power loss L_ij associated with each path 42_ij.

[0111] In some examples, the controller 40 is configured to select a corresponding antenna port 30_j for each power amplifier 20_i in a set 60 of one or more power amplifiers 20_i based on an estimate of power loss in a transmission channel associated with the antenna port 30_j and / or an estimate of power loss in a path between a power amplifier 20_i in a set 60 of one or more power amplifiers 20_i and a corresponding selectable antenna port 30_j.

[0112] In some examples, the controller 40 is configured to select, for the power amplifier 20_i of the primary component carrier, the antenna port 30_j having the best estimate of the power loss in the transmission channel associated with the antenna port 30_j.

[0113] The primary component carrier (PCC) is awarded to the best antenna 50_i (lowest transmission path loss), and the secondary component carrier (SCC) must be assigned to a combination of power amplifier 20 and antenna port 30 that does not include the power amplifier 20 and antenna port 30 previously assigned to the PCC based on other optimizations (such as minimizing back-off).

[0114] By reducing the path loss, the back-off can be minimized. In some examples, this is achieved by routing the power amplifier 20_i to its nearest antenna port 30_i.

[0115] Figure 4 An example of a switch arrangement is illustrated in which the controller 40 is configured to include switches 42_i.

[0116] The apparatus 10 comprises: a plurality of power amplifiers 20_i, a plurality of antenna ports 30_j connected to respective antenna elements 50_j; and a controller 40 configured to select a set 60 (of one or more power amplifiers 20_i) from the plurality of power amplifiers 20_i for simultaneous transmission via the respective antenna ports 30_j. Figure 4(not shown in the figure). At least some of the multiple power amplifiers 20_i have different maximum output power capabilities 22_i.

[0117] In this example, there are N antenna ports 30_j and N power amplifiers 20_i. Each power amplifier 20_i has an associated maximum output power capability 22_i. This is the maximum power level P_i at which the power amplifier 20_i can be operated by the device 10.

[0118] In this example, the controller 40 is configured to map a power amplifier 20_i to an antenna port 30_j and map an antenna port 30_j to a power amplifier 20_i via a path 42_ij (not shown). There is a mapping set between the power amplifiers 20_i in the set 60 and the corresponding antenna ports 30_j. In this example, this mapping is controlled by the state of the switch 42_j.

[0119] In this example, the power amplifier 20_i is connected to an iP(N - i + 1)T switch 42_i. The iP(N - i + 1)T switch 42_i is a switch with i poles and (N - i + 1) throws. One of these throws is connected to the antenna port 30_i. Each of the other N - i throws is connected to one of the antenna ports 30_k, where k > i, i.e., k = i + 1, i + 2, …, N. One of these poles is connected to the power amplifier 20_i. Each of the other i - 1 poles is connected to one of the throws of the corresponding switch 20_p, where p < i, i.e., p = i - 1, i - 2, …, 1.

[0120] Thus, the first power amplifier 20_1 (i = 1) is connected to a 1PNT switch 42_1. The 1PNT switch 42_1 is a switch with 1 pole and N throws. One of these throws is connected to the antenna port 30_1. Each of the other N - 1 throws is connected to one of the antenna ports 30_k, where k > 1, i.e., k = 2, 3, …, N. One of these poles (the only pole) is connected to the power amplifier 20_1.

[0121] Thus, the last power amplifier 20_N (i = N) is connected to an NP1T switch 42_N. The NP1T switch 42_N is a switch with N poles and 1 throw. One of these throws (the only throw) is connected to the antenna port 30_N. One of these poles is connected to the power amplifier 20_i. Each of the other N - 1 poles is connected to one of the throws of the corresponding switch 20_p, where p < N, i.e., p = N - 1, N - 2, …, 1.

[0122] In this example, the first power amplifier 22_1 is the most powerful power amplifier and has the maximum output power capability P_1. The last power amplifier 22_N is the least powerful power amplifier and has the minimum output power capability P_N. Figure 4 The figure illustrates the general trend that the output power capability P_i decreases as i increases.

[0123] In some examples, the output power capability P_i of the power amplifier 20_i is Pm - 10log(i) dBm.

[0124] Figure 5 The figure illustrates Figure 4 an example where N = 4.

[0125] This example illustrates the poles 44_i and throws 46_i of the corresponding switch 42_i and their connections.

[0126] In this example, the power amplifier 20_i is connected to the iP(5 - )T switch 42_i. The iP(5 - )T switch 42_i is a switch having i poles 44_i and (5 - i) throws 46_i. One of these throws is connected to the antenna port 30_i. Each of the other 5 - i throws is connected to one of the antenna ports 30_k, where k > i, i.e., k = i + 1, i + 2, ……, 4. One of these poles is connected to the power amplifier 20_i. Each of the other i - 1 poles is connected to one of the throws of the corresponding switch 20_p, where p < i, i.e., p = i - 1, i - 2, ……, 1.

[0127] Thus, it can be understood that in at least some examples, the apparatus 10 is configured to control the switching arrangement 42 between more than 40 power amplifiers 20_i and multiple antenna ports 30_j, where the switching arrangement 42 is configured to connect each of the multiple power amplifiers 20_i to at least one antenna port 30_j and to connect at least the first power amplifier among the multiple power amplifiers 20_i to any one of the multiple different antenna ports among the multiple antenna ports 30_j, where the first power amplifier among the multiple power amplifiers 20_i has the highest maximum output power capability 22_i among the multiple power amplifiers 20_i.

[0128] The controller 40 is configured to switch 42_i a power amplifier 20_1 having the highest maximum output power capability 22_1 among the multiple power amplifiers 20_i to any one of a first number of antenna ports among the multiple antenna ports 30_i, and to switch 42_i a power amplifier 20_N having the lowest maximum output power capability 22_N among the multiple power amplifiers 20_i to any one of a second number of antenna ports among the multiple antenna ports 30_j, wherein the first number is the maximum number of antenna ports 30_j to which any power amplifier among the multiple power amplifiers 20_i can switch, and the second number is the minimum number of antenna ports 30_j to which any power amplifier among the multiple power amplifiers 20_i can switch.

[0129] The power amplifier 20_1 with the highest output power capability can be switched to any of the antenna ports. The power amplifier 20_N with the lowest output power capability can be switched only to the antenna port 30_N.

[0130] The power amplifier 20_1 with the highest maximum output power capability 22_1 has the most available antenna ports 30_j, while the power amplifier 20_N with the smallest maximum output power capability 22_N has the fewest available antenna ports 30_j.

[0131] 6A to 6F The example shown is similar to Figure 4 and Figure 5 . However, in this example, there are multiple lowest output power capability power amplifiers 20_3, 20_4. The switch 42_3 connected to the pole 44_4 of the switch 42_4 does not have a throw 46_3. The switches 42_3 and 42_4 are arranged in parallel and provide alternative switching options for the power amplifiers 20_1, 20_2. However, the switch 42_4 does not provide an alternative switching option for the power amplifier 20_3. Each of the multiple lowest output power capability power amplifiers 20_3, 20_4 has a single corresponding antenna option, which is shared as an option for one or more higher output power capability power amplifiers 20_1, 20_2. Lower output power capability power amplifiers require fewer antenna options. This example reduces the complexity of the switch 42_3 when the PA efficiency "gain" begins to decrease as the output power capability decreases.

[0132] 6A to 6FThe operation of the apparatus 10 for MIMO operation of different ranks is illustrated. In these examples, the power amplifier 20_1 has a maximum output power capability level P_1 of 24dBm. In these examples, the power amplifier 20_2 has a maximum output power capability level P_1 of 24dBm-10log2dBm=21dBm. In these examples, the power amplifier 20_3 and the power amplifier 20_4 have a maximum output power capability level P_1 of 24dBm-10log3dBm=19.3dBm.

[0133] exist 6A to 6F In each of the graphs in , the same combined total transmit power target (T) of 24 dBm is obtained.

[0134] exist Fig. 6A , MIMO rank 1 is implemented using one uplink transmission (zero backoff) at 24 dBm by power amplifier 20_1. Any of the antennas 50 can be used. Thus, the best antenna 50 can be used. In the case of estimated path loss, the selection between alternative antennas can be additionally or alternatively based on the estimated path loss, which reduces the backoff. For example, it can be routed as close as possible to the power amplifier 20_1 to minimize insertion loss.

[0135] exist Figure 6B , MIMO rank 2 is achieved using uplink transmission by power amplifier 20_1 at 21 dBm (10log2dB=3dB back-off) and uplink transmission by power amplifier 20_2 at 21 dBm (zero back-off). Any of the higher indexed (i=3, 4) antennas 50 not used by power amplifier 20_1 can be used. Thus, the best antenna 50 can be used. In the case of estimated path loss, the selection between alternative antennas can be additionally or alternatively based on the estimated path loss, which reduces the back-off.

[0136] exist Figure 6C , Fig.6D , Fig. 6E MIMO rank 3 is achieved with three power amplifiers 20 for uplink transmission at 19.3 dBm.

[0137] exist Figure 6C In FIG. 1 , this is achieved using uplink transmission by power amplifier 20_1 at 19.3 dBm (4.7 dB back-off), uplink transmission by power amplifier 20_2 at 19.3 dBm, and uplink transmission by power amplifier 20_3 at 19.3 dBm (zero back-off). The total combined back-off is 6.4 dB. The maximum power back-off is 4.7 dB.

[0138] exist Fig.6DIn FIG. 1 , this is achieved using uplink transmission at 19.3 dBm by power amplifier 20_1 (4.7 dB back-off), uplink transmission at 1.7 dBm by power amplifier 20_2 (1.7 dB back-off), and uplink transmission at 19.3 dBm by power amplifier 20_4 (zero back-off). The total combined back-off is 6.4 dBm. The maximum power back-off is 4.7 dB.

[0139] exist Fig. 6E In FIG. 1 , this is achieved using uplink transmission at 19.3 dBm by power amplifier 20_2 (1.7 dB back-off), uplink transmission at 19.3 dBm by power amplifier 20_3 (zero back-off), and uplink transmission at 19.3 dBm by power amplifier 20_4 (zero back-off). The total combined back-off is 1.7 dBm. The maximum power back-off is 1.7 dB.

[0140] Assuming the path losses are equal, then Figure 6C , Fig.6D , Fig. 6E The selection between the illustrated alternative configurations of MIMO rank 3 may be based on different selection criteria.

[0141] In one example, the configuration with the smallest total combined power backoff is selected ( Fig. 6E ).

[0142] In one example, the configuration with the smallest fallback is selected ( Fig. 6E ).

[0143] In one example, antenna 50_4 is not available due to transmission channel loss (e.g., hand shielding). A configuration that does not use antenna 50_4 is selected ( Figure 6C ).

[0144] In one example, antenna 50_3 is not available due to transmission channel loss (e.g., hand shielding). A configuration that does not use antenna 50_3 is selected ( Fig.6D ).

[0145] In other examples, in the case of estimating path loss, Figure 6C , Fig.6D , Fig. 6E The selection between the illustrated alternative configurations of MIMO rank 3 may additionally or alternatively be based on an estimated path loss, which reduces power backoff.

[0146] exist Fig. 6F, MIMO rank 4 is achieved using uplink transmission at 18dBm by power amplifier 20_1 (10log4dB=6dB back-off), uplink transmission at 18dBm by power amplifier 20_2 (3dB back-off), uplink transmission at 18dBm by power amplifier 20_3 (1.3dB back-off) and uplink transmission at 18dBm by power amplifier 20_4 (1.3dB back-off).

[0147] It will therefore be appreciated that the controller 40 is configured to select a set 60 of one or more power amplifiers 20_i from the plurality of power amplifiers 20_i for use with the corresponding antenna ports 30_j in response to a requirement to increase the number of antenna ports 30_j in use.

[0148] In these examples, the controller 20 is configured to select an additional power amplifier 20_i from the remaining power amplifiers 20_i of the plurality of power amplifiers 20_i that are not currently in the set 60 to add to the set 60 of one or more power amplifiers 20_i, wherein the selected additional power amplifier 20_i is a power amplifier 20_i among the remaining power amplifiers 20_i having a lowest maximum output power capability 22_i.

[0149] This operation is performed by FIG. 6B to FIG. 6C To increase the number of uplinks, power amplifier 20_3 is added to set 60.

[0150] This operation is performed by FIG. 6B to FIG. 6D To increase the number of uplinks, power amplifier 20_4 is added to set 60.

[0151] This operation is performed by FIG. 6B to FIG. 6E To increase the number of uplinks, power amplifier 20_1 is removed from set 60, and power amplifiers 20_3, 20_4 are added.

[0152] When moving to a smaller number of members (fewer UL Tx) in the set 60, the reverse operation may deselect the power amplifiers 20 except for the power amplifier 20_i with the lowest maximum output power capability 22. This operation is performed by FIG. 6F to FIG. 6E To reduce the number of uplinks, the power amplifier 20_1 is removed from the set 60.

[0153] In the transition from rank 3 to rank 2, the target transmit power can only be achieved using power amplifier 20_1 and power amplifier 20_2. It cannot be achieved by any other combination of 2 power amplifiers. Therefore, satisfying the constraint of the target transmit power T (23dBm) limits the selection to power amplifiers 20_1, 20_2 only.

[0154] Under such constraints, the controller 40 switches on additional power amplifiers with higher maximum output power capabilities 22_i as demand increases, and switches off the current power amplifier with the lowest maximum output power capability 22_i as demand increases.

[0155] refer to Fig. 6A It can be noted that in this example, one of the multiple power amplifiers 20_1 itself meets the maximum output power requirement (T), which is controllable by the cellular telecommunication network via downlink control signaling. One power amplifier 20_1 itself meets the maximum output power requirement of the power class, while the other power amplifiers have reduced maximum output power capabilities.

[0156] Fig. 7A and Figure 7B An example of the operation of the controller 40 when the maximum output power requirement (T) changes is illustrated. In some examples this is controllable by the cellular telecommunications network via downlink control signalling.

[0157] exist Fig. 7A In, there is MIMO rank 2 operation. Power amplifier 20_2 transmits via antenna element 30_2, and power amplifier 20_4 transmits via antenna element 30_4. Power amplifier 20_1 and power amplifier 20_3 do not transmit. The maximum output power requirement (T) is P_2+P_4, which is less than P_1+P_2, but greater than P_3+P_4.

[0158] exist Figure 7B In, there is MIMO rank 2 operation. Power amplifier 20_1 transmits via antenna element 30_1, and power amplifier 20_2 transmits via antenna element 30_2. Power amplifier 20_3 and power amplifier 20_4 do not transmit. The maximum output power requirement (T) is P_1+P_2, which is greater than P_2+P_4.

[0159] In this example, as previously described, P_3 = P_4.

[0160] When the maximum output power requirement (T) increases beyond the maximum output power capability of the current set 60, the controller 40 selects a new optimal set of power amplifiers 20 and antenna ports 30, as previously described.

[0161] When the maximum output power requirement (T) decreases below the maximum output power capability of the current set 60 (which is the next lowest value after the maximum output power capability of the current set 60), the controller 40 selects a new optimal set of power amplifiers 20 and antenna ports 30 as previously described.

[0162] Therefore, consider Fig. 7A When the maximum output power requirement (T) increases to exceed the maximum output power capability (P_2+P_4) of the current set 60, the controller 40 selects a new optimal set of power amplifiers 20 and antenna ports 30, as described above. Figure 7B The configuration shown has the second highest maximum output power capability of the estimated set 60 of the same rank (P_1+P_2).

[0163] Therefore, consider Figure 7B , when the maximum output power requirement (T) decreases to below the estimated maximum output power capability of the estimated set 60 (which is the next lowest value after the maximum output power capability of the current set 60), i.e., to P_2+P_3, the controller 40 selects a new optimal set of power amplifiers 20 and antenna ports 30, as described above. For example, Fig. 7A The configuration shown has the next lowest highest maximum output power capability of the estimated set 60 of the same rank (rank 2). Fig. 7A The rank 2 configuration shown has the highest maximum output power capability P_2+P_4, which is Figure 7B The next lowest value for a rank-2 configuration after the highest maximum output power capability P_1+P_2 of the rank-2 configuration shown.

[0164] It should be understood that in some examples, the controller 40 is configured to replace a power amplifier 20_i in a set 60 of one or more power amplifiers 20_i only when the output power of the power amplifier 20_i for replacement has been maximized, in response to a requirement to increase the combined total transmit power of the set 60. The replaced power amplifier 20_i will be the lowest output power capable power amplifier or one of them (depending on the path loss). In the set 60, it will be replaced by a power amplifier with a higher output power. The allocation of power amplifiers to antennas 50s_i can be changed.

[0165] The network may request an increase in the maximum output power requirement (T) of the user equipment, for example to provide a greater range. Once the maximum output power requirement (T) request from the network exceeds the maximum output power capability of the selected current set of power amplifiers 20 60, the device will pass the UL signal from the power amplifier 20 with the lowest output power capability to the power amplifier 20 with the next largest output power capability. This process is repeated as needed until the understood maximum output power requirement (T) is met or the device 10 is using the power amplifier 20 with the maximum output power capability.

[0166] In current 5G implementations, for each antenna 50, the power amplifier 20 is designed to deliver at least 23 dBm at the antenna port 30 in a power class 3 (PC3) user equipment (UE) type of device.

[0167] When multiple power amplifiers 20 are used simultaneously, the power of each antenna 50 is reduced to maintain compliance with PC3 requirements. Therefore, the power amplifier (PA) 20 can be operated with back-off, and the amount of back-off increases as the number of power amplifiers 20 used simultaneously increases.

[0168] To achieve 23dBm total output power at the antennas in multi-UL MIMO applications, the output power of each transmitter branch must be backed off compared to the optimum maximum output power the PA is designed for. Although there are several auxiliary schemes for improving PA efficiency, this is not efficient for the PA 20.

[0169] When more transmission paths are introduced for the same frequency range by adding more power amplifiers, it is desirable to meet the demand for higher uplink bandwidth while keeping the design within an attractive current consumption range.

[0170] At least some examples improve UE power consumption efficiency in Multi-UL MIMO (6G) by allowing the UE to use a PA 20 with a lower maximum output power capability 22, thereby avoiding unnecessary efficiency-reducing power back-off 28.

[0171] The apparatus 10 is configured for, but not limited to, 6G frequencies, such as 7 GHz-20 GHz, where the PA 20 is designed for MIMO purposes and a smart allocation scheme is responsible for achieving traditional 1-Tx UL maximum power and best antenna selection (BAS) features while improving MIMO and CA / DC efficiency in terms of UE current consumption.

[0172] Once the UE 10 receives an uplink grant or request, it will apply a power allocation scheme to compare the power amplifiers supported by the UE to the antennas connected. The device 10 will then avoid unnecessary power backoff 28 in its uplink configuration while meeting the maximum output power requirement (meeting the combined transmit power target T). The proposed hardware architecture is applicable to any frequency range, but is most applicable when a single antenna element 50 (rather than an array) is used. In addition, the proposed architecture brings the same output power mitigation for carrier aggregation and dual connectivity cases in the use and allocation of PA 20. The device 10 can select the most appropriate antenna 50 to evaluate based on the DL signal (avoiding users blocking the antenna 50).

[0173] Advantages provided include:

[0174] (a) a cost, size and power consumption optimized UE transmitter apparatus 10 supporting legacy 1-TX, UL CA and UL MIMO operations,

[0175] (b) Optimal TX power utilization of PA 20 via novel switching and control methods,

[0176] (c) The proposal benefits from existing switches designed for SRS (Sounding Reference Signal),

[0177] Therefore, SRS is an integral part of the proposed architecture.

[0178] (d) PA technology-independent design for low TX power (<19dBm / threshold),

[0179] Lower current consumption design,

[0180] (e) If the required UE transmitter power for 1-TX uplink is below 19dBm / threshold, then we only need to turn on one “optimized” PA chain,

[0181] (f) The UE optimizes the uplink hardware configuration based on its own hardware capabilities and antenna routing,

[0182] (g) The proposed hardware architecture and output power control method are also applicable to CA and EN / DC configurations (inter-band operation) and have advantages, and

[0183] (h) Customized switch design with only one RF (radio frequency) line between each antenna.

[0184] Figure 4The proposed generic front-end RF architecture of the apparatus 10 for multi-UL MIMO is shown. The switch 42 at the PA output can be designed as part of the existing sounding reference signal (SRS) switching, which means that our proposal does not add additional power loss compared to existing design trends, because the loss after the power amplifier 20 is undesirable.

[0185] Use PA 20 with different output power capabilities. This provides significant improvements in cost, size and power efficiency (lower current consumption) for the UE's transmitter, as the lower output power of the PA 20 means less current and less heat, enabling the use of smaller transistors and a smaller footprint. This is an advantage for devices in the existing 5G spectrum, but is particularly important for devices in the proposed new 6G frequency range of 7-15GHz. The concept can be reconfigured if the UE supports a lower or higher number of UL-MIMO.

[0186] Figure 5 A simplification of the general concept to 4-UL MIMO is illustrated in FIG.

[0187] The device 10 has an optimized architecture for minimizing the number of "pins" of switches connected to the antennas 50_3 and 50_4 and thereby reducing losses.

[0188] Figure 6A-6F MIMO is illustrated. In the exemplary case in the figure, the output power target at the PA output is 24dBm, but it can be applied to any output power level allowed by the communication system. The example here assumes that the path loss to the shortest route antenna for each PA module is 1dB. The output power level shown at PA 20 is not the active state, but the maximum output power capability of the individual PA 20.

[0189] The device 10 has an optimized architecture for minimizing the number of "pins" of the switches connected to the antennas 30_3 and 50_4 and thereby reducing losses. The proposed architecture allows the use of one power amplifier with a maximum output power capability reduced by 3dB and two power amplifiers with a maximum output power capability reduced by about 5dB, while meeting all the requirements of the conventional architecture.

[0190] Fig. 6Ais 1 layer UL Tx of MIMO rank 1. UE 10 should be able to meet the 3GPP maximum power requirement of 23dBm at its antenna and implement the Best Antenna Selection (BAS) feature. BAS is not a 3GPP requirement, but most existing high-end smartphones use this application for coverage enhancement. Therefore, the architecture proposed in this example includes a power amplifier 20_1 with the highest output power capability, which can be switched to any one of all available antennas 50_i in the operating band to support the BAS feature. By default, the power amplifier 20_1 is connected to antenna 50_1, which will be routed as close to the power amplifier as possible to reduce insertion loss.

[0191] Figure 6B 2-layer UL Tx for MIMO rank 2 is illustrated. For 2-UL MIMO applications, the power amplifier 20_1 with the highest output power level capability (i.e., 24dBm) is backed off to 21dBm and connected by default to antenna 50_1 (which will be optimally routed for that antenna). The PA 20_2 with the second highest output power level capability (i.e., 21dBm) is connected by default to antenna 50_2 (which will be optimally routed for that antenna). When the second PA 20_2 is designed for a maximum of 21dBm, the efficiency of the PA 20_2 at 21dBm will be better than the efficiency of the PA 20_1 at the antenna 50_1 backed off to 21dBm. PA 20_1 can be switched to any of antennas 50_2, 50_3, or 50_4, and power amplifier 20_2 can be switched to antenna 50_3 or antenna 50_4. The priority order of mobile antennas in 2-UL MIMO is PA 20_1 at antenna 50_1 before PA 20_2 at antenna 50_2. This is because PA 20_1 at antenna 50_1 will better compensate for the additional path loss through the additional switch.

[0192] FIG. 6C to FIG. 6E The diagram shows 3-layer UL Tx for MIMO rank 3. For this application, three power amplifiers are operated at 19.3dBm. Figure 6C and Fig.6D In the example, the two power amplifiers 20_1 and 20_2 with the two highest output power capabilities are backed off to 19.3 dBm. The maximum output power capability of the power amplifier 20_1 is 24 dBm. The maximum output power capability of the power amplifier 20_2 is 21 dBm. Fig. 6E In the example, the power amplifier 20_1 with the highest output power capability is not used. The power amplifier 20_2 is backed off from its maximum output power capability Pmax of 21 dBm to 19.3 dBm.

[0193] Now, according to BAS, any three of the four antennas can be used as 3-UL MIMO. The most power efficient configuration is the architecture shown in 6E, where only one power amplifier 20_2 is backed off from a Pmax of 21dBm to 19.3dBm. This has the lowest back-off, and this configuration has the highest efficiency.

[0194] Fig. 6F 4-layer UL Tx of MIMO rank 4 is illustrated.

[0195] With regard to uplink carrier aggregation (ULCA), where two transmitters are active simultaneously, but in contrast to UL-MIMO, they operate on different frequencies. With the same output power and implementation advantages in ULCA as in UL MIMO, the PA 20 will be activated towards the individual antennas 50 based on the same output power control, but associated with the allocation of the primary serving cell (PCell) and the secondary serving cell (Scell) accordingly.

[0196] Figure 8 A power control method 100 is illustrated. The method provides advanced control and configuration for new and different PA capabilities, since the PA 20 can transmit at different power levels, with different effects on current consumption and heating. The method 100 relies on configuration changes of the PA 20 based on TX power regions, where the PA 20 with the highest power capability dominates. As the requested output power level decreases, the PA 20 with the highest power will hand over operation to the PA 20 with the next highest power in order of output power capability. This is shown in FIG. Figure 8 shown.

[0197] refer to Figure 8 , at box 101, the device 10 (UE) registers on the network (NW) following standard procedures.

[0198] At block 102, the UE 10 determines the active operating band in the network and measures the incoming signal strength through all metrics available within the system to indicate the received signal power from the network.

[0199] At block 103, open loop power control is activated and the transmit signal strength of the UE 10 is determined based on the received signal strength indicating the minimum UE to NW path loss.

[0200] At block 104, the UE 10 checks, depending on the implemented PA, whether the output power response is achievable only at the "strongest" PA.

[0201] If this is the case, the UE 10 configures 105 the strongest PA accordingly.

[0202] If this is not the case, the UE 10 checks 106 whether the output power response is achievable using the next "strongest" PA.

[0203] If this is the case, the UE 10 configures the next strongest PA accordingly.

[0204] If this is not the case, the UE 10 may configure whichever PA is best suited for transmission, depending on the received signal strength at any antenna (BAS).

[0205] The UE 10 then switches the selected PA to the best antenna 50 at block 109 .

[0206] If the UE 10 is in open loop mode, it performs closed loop power control 112 in step 111 , otherwise the routine ends and waits for the next output power change request 113 .

[0207] If the UE is in closed loop mode, the UE 10 keeps tracking the antenna for best reception to determine where to transmit in response to the network.

[0208] At each transmit power control (TPC) command 113 that changes the output power of the UE, the apparatus 10 repeats blocks 104 to 111.

[0209] The flow chart can be applied to any number of uplink transmitters, including PAs directed to any number of antennas. There can be different threshold levels for the checks 104, 106 to determine which PA 20 to use, Figure 8 The numbers in the figure are for illustrative purposes only. Figure 8 The control flow is applicable to both UL-MIMO and ULCA.

[0210] Fig. 9 The device 10 is illustrated with further simplified RF tracks between antennas 50. In this example, a single track interconnects switch 42_1 and switch 42_2, a single track interconnects switch 42_2 and switch 42_3, and a single track interconnects switch 42_3 and switch 42_4. In this example, the device 10 has two of the power amplifiers 20_2, 20_3 with sub-maximum output power capabilities connected via respective switches 20_2, 20_3.

[0211] Antenna 50_i is connected to the throw of nearby switch 42_i. Power amplifier 20_i is connected to the pole of 1P2T (SPDT) switch 42_1.

[0212] The antenna 50_1 is connected to the throw of the SPDT switch 42_1. The antenna 50_2 is connected to the throw of the DPDT switch 42_2. The antenna 50_3 is connected to the throw of the DPDT switch 42_3. The antenna 50_4 is connected to the throw of the SPDT switch 42_4.

[0213] The throw of the SPDT switch 42_1 is connected to the pole of the 2P2T (DPDT) switch 42_2. The throw of the DPDT switch 42_2 is connected to the pole of the 2P2T (DPDT) switch 42_3. The throw of the DPDT switch 42_3 is connected to the pole of the 2P1T (DPST) switch 42_4.

[0214] For rank 1 operation, power amplifier 20_1 may be routed to any of antennas 50_i. Power amplifier 20_2 may be routed to any of antennas 50_2, 50_3, 50_4. Power amplifier 20_3 may be routed to any of antennas 50_3, 50_4. Power amplifier 20_4 may be routed only to antenna 50_4.

[0215] Fig. 9 The hardware implementation follows Fig.10 shown Figure 8 Different power control processes are provided in.

[0216] At block 101 , the device 10 (UE) registers on the network (NW) according to standard procedures.

[0217] At block 102, the UE 10 determines the active operating band in the network and measures the incoming signal strength through all metrics available within the system to indicate the received signal power from the network.

[0218] At block 103, open loop power control is activated and the transmit signal strength of the UE 10 is determined based on the received signal strength indicating the minimum UE to NW path loss.

[0219] At block 114, the UE 10 checks, depending on the implemented PA, whether the output power response is achievable only at the "strongest" PA, ie, the highest output power region is required.

[0220] If this is the case, the UE 10 configures 115 the strongest PA with the maximum output power accordingly.

[0221] If this is not the case, the UE 10 checks 116 whether the output power response can be achieved using the next "strongest" PA, ie the next highest output power region is required.

[0222] If this is the case, the UE 10 configures one of the next strongest PAs accordingly, whereas if not, the method moves to block 118 .

[0223] For example, a determination is made at block 117 whether the output power can be achieved using a power amplifier close to the best antenna element. If so, the near-end power amplifier is used. If not, the PA with the maximum output power capability is routed to the best antenna element.

[0224] At block 118, the UE 10 may configure whichever PA is best suited for transmission based on the received signal strength at any antenna (BAS).

[0225] The UE 10 then switches the selected PA to the best antenna 50 at block 120 .

[0226] If the UE 10 is in open loop mode, it performs closed loop power control 112 in step 111 , otherwise the routine ends and waits for the next output power change request 113 .

[0227] If the UE is in closed loop mode, the UE 10 keeps tracking the antennas for best reception, determining which PAs and antennas to select for transmission in response to the network.

[0228] The near-end PA 20 as described above is considered to be the PA 20 with the least insertion loss towards the antenna. It is usually the PA 20 near the antenna and only requires a single switch to reach the antenna.

[0229] The PA 20 with the highest power capability is routed to the antenna where the next highest output power region cannot be reached.

[0230] In the prior art, for each antenna, the power amplifier is designed to deliver at least 23dBm at the antenna reference point (antenna port) in a Power Class 3 (PC3) UE type device. When the device supports 2UL MIMO, the power of each antenna is reduced to maintain compliance with the PC3 requirement, unless the UE declares PC2 (26dBm). If more than one uplink component carrier is configured, a similar reduction in absolute output power applies. The combined power of the two uplink component carriers must comply with the power class limit.

[0231] The following description targets an optimal power amplifier (PA) 20, and describes output power configuration in a single-layer operation using only one PA.

[0232] The PA output power is based on matching the required output power level according to the power class. The output power is related to the measured level at the antenna port, which means that a 23dBm power class 3 PA must output a level of 23dBm + front-end path loss due to filters, switches, matching, tuning and routing elements, i.e. any components and / or connections in the conduction path between the PA output pin and the antenna port or antenna feed point.

[0233] The output power control method needs to consider the antenna allocation in multiple transmission modes.

[0234] The controller 40 is configured to route the PA output (UL signal) to the antenna showing the best channel status for DL ​​according to the potential CA / EN-DC primary cell assignment.

[0235] This means that if one antenna 50 has the best channel status for two different operating bands, the UE 10 will choose to place the primary component carrier at the best antenna.

[0236] Next, the UE must take into account the path loss towards the antenna. Typically, calibration ensures that the PA 20 delivers the correct output power level at the antenna port 30 .

[0237] The UE 10 calibrates for each PA 20 at the antenna port 30 with minimum insertion loss, while for each PA 20 additionally measuring the incremental power on other configurable antenna ports 40 to which the PA 20 may be routed.

[0238] For single component carrier operation and optimal output power utilization, the UE 10 will apply the PA with the smallest output power capability up to its maximum absolute power level. Once the output power request from the network exceeds the capability of the PA 20, the UE 10 will pass the UL signal to the next PA 20 with output power capability until the UE 10 is using the PA 20 with the largest output power capability for uplink transmission, provided that the network continues to request an increase in output power.

[0239] In order for the UE to apply the best PA 20 to meet the output power request, the UE 10 estimates the path loss from each PA 20 to each antenna 50 that the controller routing allows to support. The path loss from each PA 20 to each supported antenna 50 is stored in the UE memory as part of the UE output calibration in production. The following items can be calibrated:

[0240] - Each frequency band.

[0241] - Each PA 20.

[0242] - Added frequency dependency in frequency step size (frequency ripple response).

[0243] - Each antenna port is served by an individual PA 20 .

[0244] -Optionally straddle output power levels if impedance matching detunes the PA.

[0245] - Data can be stored based on feedback receiver levels.

[0246] -Data may be stored based on the uplink output power configuration register setting.

[0247] -Data can be stored based on analog level adjustment.

[0248] The UE 10 may configure the Tx uplink path based on:

[0249] - Determine the maximum output power level of each PA 20.

[0250] - Determine the best antenna 50 based on the Rx input power / quality for the same operating band.

[0251] - Determine which PA 20 can service the output power request, prioritizing from the PA with the smallest output power upwards, including maximum output power capability and best antenna additional path loss (calibration).

[0252] The power antenna 20_i has a maximum output power capability P_i. The antenna 40_j has a transmission channel loss T_j. The path 42ij from the power amplifier 20_i to the antenna 50_j has a power loss L_ij.

[0253] Consider the metric Zij, where for each i, j, Zij=P_i-L_iy-T_y.

[0254] The controller can select the power amplifier 20_i and antenna element 50_j by identifying the PA 20_i that is available and has the lowest possible maximum output power capability, for example, what is the column in the table below that can support the required power with the highest index i. The controller 40 then selects the best possible antenna index j for that index, for example, the best row in that column. This identifies the highest output power capability at the antenna with the least loss.

[0255]

[0256] Applying this algorithm to the above table, for different maximum power requirements T, PA 20_i index i and antenna 50_j index j produces the following pairs (i, j).

[0257] T: 15, 16, 17, 18*, 19*, 20, 21*, 22, 23

[0258] Use: (4,3), (4,3), (4,3), (3,3), (2,3), (2,3), (1,3), (1,3), (1,3)

[0259]

[0260]

[0261] Applying this algorithm to the above table produces the following pairs (i, j) for different maximum power requirements T, PA index i and antenna index j.

[0262] T: 15, 16, 17, 18*, 19*, 20, 21*, 22, 23

[0263] Use: (4,4), (4,4), (4,4), (3,4), (2,2), (2,2), (1,2), (1,2), (1,2)

[0264]

[0265] Applying this algorithm to the above table produces the following pairs (i, j) for different maximum power requirements T, PA index i and antenna index j.

[0266] T: 15, 16, 17, 18*, 19*, 20, 21*, 22, 23

[0267] Use: (4,4), (4,4), (4,4), (3,3), (2,2), (2,2), (1,1), (1,1), (1,1)

[0268] These examples show situations where the PA selection changes at different output power request states (T). These examples show that PA 20 can be routed to the same antenna or to different antennas with respect to the output power request. The advantage of this scheme is that the PA 20_4 with the smallest output power capability is used for the absolute highest level before the "larger PA" is switched on, which means that each of the output power steps to achieve the maximum output power of the supported power class is always performed with the focus on using the PA with the smallest power consumption at that time.

[0269] In uplink multi-band operation (e.g., carrier aggregation), the UE 10 can prioritize the primary component carrier (PCC). This affects the best antenna selection because the uplink priority of the PCC is higher than the secondary component carrier (SCC). Only uplink configurations with simultaneous transmission of two component carriers in the same time slot are considered. In a multi-carrier configuration, the PCC follows the power control scheme described above, while the power control scheme of the SCC must additionally check the PCC antenna selection when using PA (separate front-end component) and antenna routing to avoid also selecting the antenna selected for the PCC.

[0270] Fig.11 An example of a method 500 is illustrated, the method comprising:

[0271] At block 502 , a set 60 of one or more power amplifiers 20 — i is selected from a plurality of power amplifiers 20 — i for simultaneous transmission via respective antenna ports 30 — j , wherein at least some of the plurality of power amplifiers 20 — i have different maximum output power capabilities 22 — i .

[0272] At block 504 , a set 60 of one or more power amplifiers 20 — i selected from the plurality of power amplifiers 20 — i are used to transmit simultaneously via respective antenna ports 30 — j .

[0273] Fig.12 An example of a controller 400 suitable for use with the device 10 is shown. An implementation of the controller 400 may be controller circuitry. The controller 400 may be implemented solely in hardware, have certain aspects in software including firmware alone, or may be a combination of hardware and software (including firmware).

[0274] like Fig.12 As shown, the controller 400 may be implemented using instructions that enable hardware functionality, for example, by using executable instructions of a computer program 406 in a general or special purpose processor 402, which may be stored on a computer readable storage medium (disk, memory, etc.) for execution by such processor 402.

[0275] The processor 402 is configured to read from and write to the memory 404. The processor 402 may also include an output interface via which data and / or commands are output by the processor 402 and an input interface via which data and / or commands are input to the processor 402.

[0276] The memory 404 stores a computer program 406, which includes computer program instructions (computer program code) that control the operation of the device 10 when loaded into the processor 402. The computer program instructions of the computer program 406 provide logic and routines that enable the device to perform the methods shown in the drawings. The processor 402 can load and execute the computer program 406 by reading the memory 404.

[0277] The device 10 comprises:

[0278] at least one processor 402; and

[0279] At least one memory 404 storing instructions that, when executed by at least one processor 402, cause the apparatus to at least:

[0280] A set 60 of one or more power amplifiers 20_i is selected from a plurality of power amplifiers 20_i for simultaneous transmission via respective antenna ports 30_j, wherein at least some of the plurality of power amplifiers 20_i have different maximum output power capabilities 22_i.

[0281] like Fig.13 As shown, the computer program 406 may arrive at the apparatus 10 via any suitable delivery mechanism 408. The delivery mechanism 408 may be, for example, a machine-readable medium, a computer-readable medium, a non-transitory computer-readable storage medium, a computer program product, a memory device, a recording medium such as a compact disk read-only memory (CD-ROM) or a digital versatile disk (DVD) or a solid-state memory, an article of manufacture including or tangibly embodying the computer program 406. The delivery mechanism may be a signal configured to reliably transfer the computer program 406. The apparatus 10 may propagate or send the computer program 406 as a computer data signal.

[0282] A computer program instruction for causing an apparatus to at least perform the following operations or for at least performing the following operations:

[0283] A set 60 of one or more power amplifiers 20_i is selected from a plurality of power amplifiers 20_i for simultaneous transmission via respective antenna ports 30_j, wherein at least some of the plurality of power amplifiers 20_i have different maximum output power capabilities 22_i.

[0284] The computer program instructions may be included in a computer program, a non-transitory computer readable medium, a computer program product, a machine readable medium. In some but not necessarily all examples, the computer program instructions may be distributed over more than one computer program.

[0285] Although memory 404 is illustrated as a single component / circuitry, it may be implemented as one or more separate components / circuitry, some or all of which may be integrated / removable, and / or may provide permanent / semi-permanent / dynamic / cached storage.

[0286] Although processor 402 is illustrated as a single component / circuitry, it may be implemented as one or more separate components / circuitry, some or all of which may be integrated / removable.Processor 402 may be a single-core or multi-core processor.

[0287] References to "computer-readable storage medium," "computer program product," "tangibly embodied computer program," etc., or "controller," "computer," "processor," etc., should be understood to cover not only computers with different architectures, such as single / multi-processor architectures and sequential (von Neumann) / parallel architectures, but also special-purpose circuits, such as field-programmable gate arrays (FPGAs), application-specific circuits (ASICs), signal processing devices, and other processing circuit systems. References to computer programs, instructions, code, etc., should be understood to cover software for programmable processors, or firmware, such as the programmable content of hardware devices, whether instructions for a processor, or configuration settings for a fixed-function device, gate array, or programmable logic device, etc.

[0288] As used in this application, the term "circuitry" may refer to one, more, or all of the following:

[0289] (a) hardware circuit implementation only (such as implementation in analog and / or digital circuitry only) and

[0290] (b) a combination of hardware circuitry and software such as (where applicable):

[0291] (i) a combination of analog and / or digital hardware circuits and software / firmware, and

[0292] (ii) any portion of hardware processor(s) (including digital signal processor(s)), software and memory(s) with software that work together to cause a device such as a mobile phone or server to perform various functions, and

[0293] (c) Hardware circuits and / or processor(s), such as microprocessor(s) or portions of microprocessor(s), that require software (e.g., firmware) for operation, but where the software is not required for operation, the software may not be present.

[0294] This definition of circuitry applies to all uses of the term in this application, including in any claims. As another example, as used in this application, the term circuitry also covers an implementation of hardware-only circuits or processors and their (or their) accompanying software and / or firmware. For example, if applicable to a particular claim element, the term circuitry also covers a baseband integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing or network device.

[0295] The blocks shown in the figures may represent steps in a method and / or code segments in a computer program 406. The illustration of a particular order of blocks does not necessarily imply a required or preferred order for the blocks, and the order and arrangement of the blocks may vary. In addition, some blocks may be omitted.

[0296] Where a structural feature is described, it may be replaced by a means for performing one or more of the functions of the structural feature, whether that function or those functions are described explicitly or implicitly.

[0297] The operating resonant mode (operating bandwidth) is the frequency range over which the antenna can operate effectively. The operating resonant mode (operating bandwidth) can be defined as the return loss S11 of the antenna 20 being greater than the operating threshold T_op, such as 3 or 4 dB, and the radiation efficiency (er) being greater than the operating threshold, such as -3 dB in the efficiency diagram. The radiation efficiency refers to the ratio of the power delivered to the radiation resistance (Rrad) of the antenna to the total power delivered to the antenna: er = (Rrad) / (RL + Rrad), where RL = loss resistance (which includes the dissipative loss of the antenna itself). It should be understood that "radiation efficiency" does not include power losses due to poor VSWR (impedance mismatch losses in the matching network, which is not part of the antenna but an additional circuit). "Total radiation efficiency" includes "radiation efficiency" and power losses due to poor VSWR [in dB]. The efficiency operating threshold can also be expressed as "total radiation efficiency" instead of "radiation efficiency".

[0298] As used herein, "module" refers to a unit or device that does not include certain parts / components added by the final manufacturer or user. The device 10 may be a module.

[0299] The above example uses the application as an enabling component for:

[0300] Automotive systems; telecommunications systems; electronic systems, including consumer electronics; distributed computing systems; media systems for generating or rendering media content, including audio, visual and audiovisual content and mixed, mediated, virtual and / or augmented reality; personal systems, including personal health systems or personal fitness systems; navigation systems; user interfaces, also known as human-machine interfaces; networks, including cellular, non-cellular and optical networks; ad hoc networks; the Internet; the Internet of Things; virtualized networks; and related software and services.

[0301] The device 10 or module may be implemented in any vehicle (land / air / water) as an add-on component or integrated in any part of the vehicle.

[0302] According to the examples of the present disclosure, the device may be provided in an electronic device, for example, a mobile terminal. However, it should be understood that the mobile terminal is merely an illustration of an electronic device that will benefit from the implementation of the present disclosure, and therefore, it should not be considered to limit the scope of the present disclosure to this. Although in some implementation examples, the device may be provided in a mobile terminal, other types of electronic devices, such as but not limited to: mobile communication devices, handheld portable electronic devices, wearable computing devices, portable digital assistants (PDAs), pagers, mobile computers, desktop computers, televisions, gaming devices, laptop computers, cameras, video recorders, GPS devices, and other types of electronic systems can easily adopt the examples of the present disclosure. In addition, devices can easily adopt the examples of the present disclosure, regardless of their intention to provide mobility.

[0303] The term "comprise" is used in this document in an inclusive rather than exclusive sense. That is, any reference to X including Y means that X may include only one Y or may include more than one Y. If the exclusive meaning of "comprise" is intended, it will be clearly stated in the context by referring to "comprising only one" or using "consisting".

[0304] Throughout this specification, "connected," "coupled," and "in communication" and their derivatives refer to being operationally connected / coupled / in communication. It should be understood that any number or combination of intervening components (including no intervening components) may be present, i.e., to provide direct or indirect connection / coupling / in communication. Any such intervening components may include hardware and / or software components.

[0305] As used herein, the term "determine / determining" (and grammatical variations thereof) may include at least: calculating, computing, processing, deriving, measuring, investigating, identifying, searching (e.g., searching in a table, a database, or another data structure), confirming, etc. In addition, "determining" may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), obtaining, etc. In addition, "determine / determining" may include resolving, selecting, choosing, establishing, etc.

[0306] In this specification, reference is made to various examples. The description of features or functions associated with an example indicates that those features or functions are present in the example. The use of the term "example" or "for example" or "may" or "can" in the text indicates (whether explicitly stated or not) that such features or functions are present in at least the described example, whether described as an example or not, and they may but not necessarily be present in some or all other examples. Therefore, "example" or "for example" or "may" or "can" refers to a specific instance in a class of examples. The attributes of an instance may be attributes of only that instance or attributes of a class or attributes of a subclass of a class including some but not all instances in the class. Therefore, it is implicitly disclosed that features described with reference to one example rather than with reference to another example may be used as part of a working combination in the other example where possible, but do not necessarily have to be used in the other example.

[0307] Although the examples have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the claims.

[0308] Features described in the preceding description may be used in other combinations than the combinations explicitly described above.

[0309] Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

[0310] Although features have been described with reference to certain examples, those features may also be present in other examples whether described or not.

[0311] The terms "a", "an" or "the" as used in this document have an inclusive rather than exclusive meaning. That is, any reference to X that includes a / an / the Y indicates that X may include only one Y or may include multiple Ys, unless the context clearly indicates otherwise. If the exclusive meaning of "a", "an" or "the" is intended, it will be clearly stated in the context. In some cases, "at least one" or "one or more" may be used to emphasize the inclusive meaning, but the absence of these terms should not be regarded as inferring any exclusive meaning.

[0312] The presence of a feature (or combination of features) in a claim is a reference to the feature or (combination of features) itself, as well as to features that achieve substantially the same technical effect (equivalent features). Equivalent features include, for example, features that are variants and achieve substantially the same result in substantially the same way. Equivalent features include, for example, features that perform substantially the same function in substantially the same way to achieve substantially the same result.

[0313] In this specification, reference has been made to various examples, using adjectives or adjective phrases to describe features of the examples. Such description of a characteristic associated with an example indicates that the characteristic exists in some examples exactly as described and in other examples substantially as described.

[0314] The above description describes some examples of the present disclosure, however, those of ordinary skill in the art will be aware of possible alternative structures and method features that provide equivalent functionality to the specific examples of such structures and features described above, and for the sake of brevity and clarity, these alternative structures and features are omitted from the above description. Nevertheless, the above description should be understood to implicitly include references to such alternative structures and method features that provide equivalent functionality, unless such alternative structures or method features are explicitly excluded in the above description of examples of the present disclosure.

[0315] While an effort has been made in the foregoing description to draw attention to those features regarded as being of significance, it should be understood that the applicant may seek protection by way of claims for any patentable feature or combination of features mentioned above and / or shown in the drawings, whether or not emphasis has been placed thereon.

Claims

1. A device for communication, comprising: a plurality of power amplifiers, wherein at least some of the plurality of power amplifiers have different maximum output power capabilities; Multiple antenna ports; A control component is configured to select a set of one or more power amplifiers from the plurality of power amplifiers for simultaneous transmission via corresponding antenna ports. 2 . The apparatus according to claim 1 , wherein the control component is configured to control a combined total transmit power of the set of one or more power amplifiers to be less than or equal to a combined total transmit power target. 3 . The apparatus according to claim 1 , wherein the control component is configured to select the set of power amplifiers such that the power amplifiers in the set have different maximum output power capabilities.

4. An apparatus according to claim 1, 2 or 3, wherein the control component is configured to select the set of power amplifiers so that the power amplifiers in the set have a minimum maximum output power capability sufficient to make the combined total transmit power of the set of one or more power amplifiers meet a combined total transmit power target.

5. An apparatus according to claim 1, 2 or 3, wherein the control component is configured to evenly distribute the combined total transmission power of the set of one or more power amplifiers over the set of one or more power amplifiers, wherein the power amplifiers in the set are controlled to have the same power output at the same time.

6. An apparatus according to any of the preceding claims, wherein the control component is configured to select a set of one or more power amplifiers from the multiple power amplifiers for simultaneous transmission via corresponding antenna ports, and to allocate a combined total transmit power of the set of one or more power amplifiers over the set of one or more power amplifiers, reducing or minimizing a backoff from the maximum output power capability of the power amplifiers to achieve allocation of the maximum total transmit power target over a required number of power amplifiers.

7. An apparatus according to claim 2, 4, 5 or 6, or any of the preceding claims dependent on claim 2, 3 or 5, wherein the combined total transmit power of the set of one or more power amplifiers is determined at the corresponding antenna port and includes an estimate of the path loss between each power amplifier in the set of one or more power amplifiers and its corresponding antenna port.

8. An apparatus according to any of the preceding claims, wherein the control component is configured to replace a power amplifier in the set of one or more power amplifiers in response to a requirement to increase the combined total transmit power of the set only when the output power of the power amplifier to be replaced has reached its maximum output power capability.

9. An apparatus according to any of the preceding claims, wherein the control component is configured to select an additional power amplifier from the remaining power amplifiers of the multiple power amplifiers that are not currently in the set to add to the set of one or more power amplifiers, wherein the selected additional power amplifier is the power amplifier among the remaining power amplifiers having the lowest maximum output power capability.

10. An apparatus according to any of the preceding claims, wherein the control component is configured to select an antenna port for each of the power amplifiers in the set of one or more power amplifiers based on an estimate of power loss in a transmission channel associated with the antenna port and / or an estimate of power loss in a path between the power amplifier in the set of one or more power amplifiers and the corresponding selectable antenna port.

11. The apparatus according to any of the preceding claims, wherein the control means is configured to select, for a power amplifier of a primary carrier, the antenna port having the best estimate of the power loss in a transmission channel associated with the antenna port.

12. An apparatus according to any one of the preceding claims, wherein the control component is configured to control a switching arrangement between the multiple power amplifiers and the multiple antenna ports, wherein the switching arrangement is configured to connect each of the multiple power amplifiers to at least one antenna port, and to connect at least a first power amplifier of the multiple power amplifiers to any one of a plurality of different antenna ports of the multiple antenna ports, wherein the first power amplifier of the multiple power amplifiers has the highest maximum output power capability among the multiple power amplifiers.

13. An apparatus according to any one of the preceding claims, wherein the control component is configured to switch a power amplifier having the highest maximum output power capability among the multiple power amplifiers to any one of a first number of antenna ports among the multiple antenna ports, and to switch a power amplifier having the lowest maximum output power capability among the multiple power amplifiers to any one of a second number of antenna ports among the multiple antenna ports, wherein the first number is the maximum number of antenna ports to which any power amplifier among the multiple power amplifiers can be switched, and the second number is the minimum number of antenna ports to which any power amplifier among the multiple power amplifiers can be switched.

14. The apparatus of any preceding claim, comprising a plurality of antennas, wherein each antenna of the plurality of antennas is coupled to one antenna port of the plurality of antenna ports for at least transmission.

15. An apparatus according to any preceding claim, comprised in a user equipment configured for communication with a cellular telecommunications network, wherein one or more power amplifiers of the plurality of power amplifiers are configurable for simultaneous uplink transmissions to the cellular telecommunications network.

16. The apparatus of claim 15, wherein one of the plurality of power amplifiers itself meets a maximum output power requirement controllable by the cellular telecommunication network via downlink control signaling.

17. A method for communication, comprising: A set of one or more power amplifiers is selected from a plurality of power amplifiers for simultaneous transmission via corresponding antenna ports, wherein at least some of the plurality of power amplifiers have different maximum output power capabilities.

18. A computer program comprising instructions that, when executed by one or more processors, cause: selecting a set of one or more power amplifiers from a plurality of power amplifiers for simultaneous transmission via corresponding antenna ports, wherein at least some of the plurality of power amplifiers have different maximum output power capabilities.

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