Peak-to-average power ratio modification

Abstract

According to one example aspect of the present disclosure, there is provided an apparatus configured to transmit a first sounding reference signal to a network, acquire a second sounding reference signal having a lower PAPR than the first sounding reference signal from the first sounding reference signal based on a peak-to-average power ratio (PAPR) adjustment signal received in the apparatus from the network, and transmit the second sounding reference signal to the network. And transmitting the second sounding reference signal to the network.

Description

Technical Field

[0001] The present disclosure relates to managing peak-to-average power ratio in wireless communication systems, such as, for example, cellular communication systems. Background Art

[0002] The positioning of user equipment (UE) is of interest in cellular communication systems. Since there are several positioning mechanisms, positioning can be performed using different techniques. For example, the UE may be equipped with a satellite positioning receiver, which the UE may utilize to determine an estimate of its position and report the estimate to the network.

[0003] Alternatively or additionally, the UE may transmit a sounding reference signal SRS to enable the network to determine an estimate of the UE's position based on reception of the SRS. The SRS may also be used for other purposes, such as estimating uplink channel quality at the base station side. Summary of the invention

[0004] According to some aspects, the subject matter of independent claims is provided. Some embodiments are defined in the dependent claims. The scope of protection sought by various embodiments of the present invention is defined by the independent claims. The embodiments, examples and features described in this specification that do not fall within the scope of the independent claims (if any) are to be interpreted as examples that help to understand the various embodiments of the present invention.

[0005] According to a first aspect of the present disclosure, a device is provided, which includes at least one processing core and at least one memory storing instructions, which instructions, when executed by at least one processor core, cause the device to at least: send a first sounding reference signal to a network, obtain a second sounding reference signal having a lower PAPR than the first sounding reference signal from the first sounding reference signal based on a peak-to-average power ratio (PAPR) adjustment signal received in the device from the network, and transmit the second sounding reference signal to the network.

[0006] According to a second aspect of the present disclosure, a device is provided, which includes at least one processing core and at least one memory storing instructions, which instructions, when executed by at least one processor core, cause the device to at least: first receive a first sounding reference signal from a user equipment, and then receive a second sounding reference signal, the second sounding reference signal having a lower peak-to-average power ratio (PAPR) than the first sounding reference signal, and use frequency domain symbols of both the first sounding reference signal and the second sounding reference signal in a positioning or radar process of the user equipment.

[0007] In some embodiments, the apparatus is further configured to: provide a PAPR adjustment signal to the user equipment, wherein the PAPR adjustment signal indicates a PAPR difference between the first sounding reference signal and the second sounding reference signal.

[0008] In some embodiments, the apparatus is further configured to receive a third sounding reference signal from the user equipment, the third sounding reference signal having a lower PAPR than the second sounding reference signal, and adopt a frequency domain symbol of the third sounding reference signal received during the positioning or radar process of the user equipment.

[0009] According to a third aspect of the present disclosure, a device is provided, which includes at least one processing core and at least one memory storing instructions, which instructions, when executed by at least one processor core, enable the device to at least: receive positioning information related to a user equipment as part of a positioning process, determine a peak-to-average power ratio (PAPR) adjustment signal, the PAPR adjustment signal indicating how much the PAPR can be reduced from the PAPR of a first sounding reference signal used by the user equipment in the positioning process, and provide the PAPR adjustment signal to the user equipment via a radio access network.

[0010] In some embodiments, the apparatus is further configured to, after reducing the PAPR based on the first PAPR adjustment signal, determine and provide a second PAPR adjustment signal to the user equipment via the radio access network, the second PAPR adjustment signal indicating how much further the PAPR can be reduced.

[0011] According to a fourth aspect of the present disclosure, a method is provided, comprising: sending a first sounding reference signal from a device to a network, acquiring a second sounding reference signal having a lower PAPR than the first sounding reference signal from the first sounding reference signal based on a peak-to-average power ratio (PAPR) adjustment signal received in the device from the network, and sending the second sounding reference signal to the network.

[0012] According to a fifth aspect of the present disclosure, a method is provided, comprising: first receiving a first sounding reference signal from a user equipment, and then receiving a second sounding reference signal, the second sounding reference signal having a lower peak-to-average power ratio (PAPR) than the first sounding reference signal, and using frequency domain symbols of both the first sounding reference signal and the second sounding reference signal in a positioning or radar process of the user equipment.

[0013] According to a sixth aspect of the present disclosure, a method is provided, comprising: receiving positioning information related to a user equipment as part of a positioning process, determining a peak-to-average power ratio (PAPR) adjustment signal, the PAPR adjustment signal indicating how much the PAPR can be reduced from the PAPR of a first sounding reference signal used by the user equipment in the positioning process, and providing the PAPR adjustment signal to the user equipment via a radio access network.

[0014] According to a seventh aspect of the present disclosure, a device is provided, comprising components for: sending a first sounding reference signal to a network, acquiring a second sounding reference signal having a lower PAPR than the first sounding reference signal from the first sounding reference signal based on a peak-to-average power ratio (PAPR) adjustment signal received from the network in the device, and sending the second sounding reference signal to the network.

[0015] According to an eighth aspect of the present disclosure, a device is provided, which includes components for: first receiving a first sounding reference signal from a user equipment, and then receiving a second sounding reference signal, the second sounding reference signal having a lower peak-to-average power ratio (PAPR) than the first sounding reference signal, and using frequency domain symbols of both the first sounding reference signal and the second sounding reference signal in a positioning or radar process of the user equipment.

[0016] According to a ninth aspect of the present disclosure, a device is provided, comprising components for: receiving positioning information related to a user equipment as part of a positioning process, determining a peak-to-average power ratio (PAPR) adjustment signal, the PAPR adjustment signal indicating how much the PAPR can be reduced from the PAPR of a first sounding reference signal used by the user equipment in the positioning process, and providing the PAPR adjustment signal to the user equipment via a radio access network.

[0017] According to the tenth aspect of the present disclosure, a non-transitory computer-readable medium having a computer-readable instruction set stored thereon is provided, which, when executed by at least one processor, causes a device to at least: send a first sounding reference signal to a network, obtain a second sounding reference signal having a lower PAPR than the first sounding reference signal from the first sounding reference signal based on a peak-to-average power ratio (PAPR) adjustment signal received in the device from the network, and send the second sounding reference signal to the network.

[0018] According to the eleventh aspect of the present disclosure, there is provided a non-transitory computer-readable medium having a computer-readable instruction set stored thereon, which, when executed by at least one processor, causes the device to at least: first receive a first sounding reference signal from a user equipment, and then receive a second sounding reference signal, the second sounding reference signal having a lower peak-to-average power ratio (PAPR) than the first sounding reference signal, and use frequency domain symbols of both the first sounding reference signal and the second sounding reference signal in a positioning or radar process of the user equipment.

[0019] According to the twelfth aspect of the present disclosure, there is provided a non-transitory computer-readable medium having a computer-readable instruction set stored thereon, which, when executed by at least one processor, causes the device to at least: receive positioning information related to a user equipment as part of a positioning process, determine a peak-to-average power ratio (PAPR) adjustment signal, the PAPR adjustment signal indicating how much the PAPR can be reduced from the PAPR of a first sounding reference signal used by the user equipment in the positioning process, and provide the PAPR adjustment signal to the user equipment via a radio access network. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 An example system is shown in accordance with at least some embodiments of the present invention;

[0021] Figure 2A An example SRS resource block is shown;

[0022] Figure 2B shows how PAPR reduction affects frequency domain samples for two distortion levels;

[0023] Figure 2C It shows that the PAPR is improved by the CCDF of the PAPR value;

[0024] Figure 2D and Figure 2E is a range angle mapping with unmodified and modified SRS to reduce PAPR;

[0025] Figure 3 An example apparatus capable of supporting at least some embodiments of the present invention is shown;

[0026] Figure 4 illustrates signaling in accordance with at least some embodiments of the present invention; and

[0027] Figure 5 is a flow chart of a method according to at least some embodiments of the present invention. DETAILED DESCRIPTION

[0028] A process is described herein that enables the transmission power of a signal (such as, for example, a positioning sounding reference signal SRS) in a user equipment UE to be reduced. More precisely, the peak-to-average power ratio PAPR of a signal (such as an SRS) is reduced without significantly affecting the quality of the signal transmission process. For example, the signal can be provided in a positioning or radar process. In a battery-powered UE, the reduced transmission power is a beneficial technical effect in terms of energy saving and extending battery life. The user equipment obtains a reduced PAPR waveform and uses both the original waveform and the reduced PAPR waveform to provide signals such as SRS. Signals received in the network using these two waveforms can be used in processes such as positioning processes.

[0029] Figure 1 An example system according to at least some embodiments of the present invention is shown. The system includes a base station 130 communicating with UEs 110, 120. A radio link 131 connects the base station 130 with the UE 110, and a radio link 132 connects the base station 130 and the UE 120. The radio links 131, 132 may be bidirectional, including an uplink UL for transmitting information from the respective UEs 110, 120 to the base station 130 and a downlink DL for transmitting information from the base station 130 to the respective UEs 110, 120. For example, the base station 130 may be a distributed base station including a centralized unit CU assigned a radio resource control RRC protocol and one or more distributed units DU assigned a radio link control RLC protocol.

[0030] Base station 130 is also communicatively coupled to core network node 140, which may include, for example, a mobility management entity MME, a location management function LMF, or an access and mobility management function AMF. Core network node 140 may be coupled to another core network node and to network 150, which may include, for example, the Internet or a corporate network. The system may communicate with other networks via network 150. For clarity, the system may be described in detail in detail in the following sections. Figure 1 Examples of other core network nodes not shown include gateways and subscriber information repositories.

[0031] For example, the radio links 131, 132 may conform to the Long Term Evolution LTE technology or the New Radio NR technology, also referred to as the fifth generation 5G. LTE and NR are standardized by the Third Generation Partnership Project 3GPP. In particular, the radio links 131, 132 may include a set of subbands, each subband being a frequency resource used between a base station and a UE. For example, there may be up to 12 subbands or up to 18 subbands. There may be more than 18 subbands. For example, the subbands in the subband set may form a continuous block of subbands in frequency space.

[0032] Positioning UEs 110, 120 is of interest for many different reasons, such as network management, public safety, and enabling various location-based services. Positioning refers to the process of generating an estimate of a UE's geographic location, either in geographic coordinates or otherwise specified, such as a street address or a coordinate system specific to a cellular network.

[0033] For example, the positioning process can be based on positioning SRS sent by UE 110, 120 in the uplink, which are received in more than one base station. The positioning SRS is designed to have a sufficient range to reach other base stations in addition to the base station controlling the serving cell. In addition, the positioning SRS is intended to cover the entire used bandwidth, where resource elements are distributed over different orthogonal frequency division multiplexing OFDM symbols so as to optimally cover all subcarriers. Therefore, the positioning SRS can be designed to have a comb-based pattern similar to the positioning reference signal PRS used in the downlink direction. The positioning SRS was initially designed to have a low PAPR, however, as will be discussed herein in the context of, for example, NR, LTE, and the sixth generation 6G technology, reducing its PAPR further produces more benefits.

[0034] There are several different types of UE 110, 120. Smartphones, connected car connection devices, IoT devices and reduced capacity UEs can be used for different purposes. For example, smartphones are equipped with high-definition color displays and powerful processors. Therefore, smartphones usually have to be recharged every few days because they consume a lot of power. Connected car UE connection devices are configured to connect the car to a cellular network and therefore do not have to have a display and can also be powered by the car's power system, which provides sufficient power for the device. For example, IoT IoT devices can be more energy-constrained than smartphones. For example, an IoT device can be a smart utility meter or a connected motion sensor. The battery life of a reduced capacity RedCap UE is even longer than that of a typical IoT device. Compared to IoT devices, reduced capacity UEs can be more extensively designed to minimize energy consumption.

[0035] Thus, the UE may be an energy-constrained device, such as a capacity reduction or low-power high-precision positioning LPHAP UE that requires energy conservation. UE devices, such as energy-constrained UE devices, typically have a nonlinear power amplifier PA, and thus reducing the PAPR by enabling the PA to operate in a linear operating region helps to effectively linearize the output at the PA. A more linear output enhances the overall positioning quality and enables more precise power control of the transmission.

[0036] In the positioning process described herein, an initial SRS waveform is generated at the UE. The initial or first waveform may be generated based on at least one of the 3GPP standard or positioning requirements. Alternatively, the first waveform may be stored in the UE and retrieved from the memory of the UE for use. Examples of positioning requirements include accuracy and delay, where delay is the time delay in obtaining a position estimate.

[0037] Then, the UE sends an SRS in the uplink direction based on the first waveform. In the core network, the LMF determines the PAPR level requirement based on the SRS sent by the UE using the first waveform, according to one or more of, for example, UE capabilities, UE mobility, and channel conditions. Examples of channel conditions include, for example, line-of-sight LOS or non-line-of-sight NLOS states, signal-to-interference-and-noise ratio SINR, reference signal received power RSRP, and reference signal received quality RSRQ. The PAPR requirement describes the extent to which the PAPR can be reduced for the transmission of the second SRS from the UE. For example, if the channel conditions are favorable to the UE, such as a static channel, the PAPR requirement may indicate a greater PAPR reduction. On the other hand, if the channel conditions are difficult, such as in a high mobility situation, the PAPR requirement may indicate a smaller PAPR reduction. Therefore, the LMF may be configured to determine the PAPR requirement based at least in part on the radio channel conditions between the UE and the serving base station. The LMF indicates the selected PAPR requirement to the UE in the form of a PAPR adjustment signal, for example, in LTE positioning protocol LPP signaling. The PAPR adjustment signal indicates to the UE the extent to which the PAPR is to be reduced from the PAPR of the first waveform.

[0038] The UE sending the SRS using the first waveform may be referred to as the UE sending the first SRS. Similarly, the UE sending the SRS using the second waveform may be referred to as the UE sending the second SRS.

[0039] The UE may confirm its acceptance of the proposed PAPR level back to the LMF in response to receiving and accepting the PAPR adjustment signal, or the UE may instead propose a different PAPR level. If the UE proposes a different PAPR level, the LMF may send a corrected PAPR adjustment signal to instruct the UE to use a different PAPR level instead of the PAPR level indicated by the original PAPR adjustment signal.

[0040] In response to the PAPR adjustment signal or the corrected PAPR adjustment signal (if present), the UE applies a PAPR reduction algorithm to obtain a second waveform having a lower PAPR from the first waveform. When using the PAPR reduction algorithm, the PAPR adjustment signal or the corrected PAPR adjustment signal (if present) is used when selecting the degree of PAPR reduction to be obtained. The UE then sends an SRS having the second waveform to the network. The iterative clipping and filtering (ICF) algorithm described in reference [1] is an example of a PAPR reduction algorithm. Another example of a PAPR reduction algorithm is based on a harmony search and is described in reference [2].

[0041] The base station serving the UE can then use the frequency domain symbols from the SRS sent using the first waveform and the frequency domain symbols from the SRS sent using the second waveform to perform positioning or radar processing of the UE. For example, the process can be repeated by sending at least one second PAPR adjustment signal from the LMF to the UE according to the radio channel conditions between the UE and the serving base station. When the second PAPR adjustment signal is sent to the UE, the UE obtains a third waveform having a lower PAPR than the second waveform from the first waveform or the second waveform, wherein the PAPR of the third waveform is indicated by the second PAPR adjustment signal. The UE then uses the third waveform to send the SRS. The base station uses the frequency domain symbols from the SRS sent using the first waveform, the second waveform, and the third waveform in the positioning or radar process.

[0042] For example, in the case of static radio channel or low mobility radio channel conditions, the PAPR may be reduced more than in the case of high mobility, and therefore the LMF may indicate a PAPR adjustment signal that requires the UE to reduce the PAPR of the second waveform more than in the case of high mobility UEs. Reducing the PAPR results in reducing the transmit power at the UE, providing energy savings and reducing interference levels in the system. In addition, nonlinearity caused by the UE's PA is reduced, which is an additional benefit.

[0043] In some embodiments, the serving base station (rather than the LMF) determines the content of the PAPR adjustment signal used by the UE when acquiring the second SRS waveform. For example, the base station may send the PAPR adjustment signal as part of the resources allocated to the UE for sending the SRS.

[0044] Figure 2A An example SRS resource block is shown. In order to reduce PAPR, the frequency domain symbols of the SRS waveform are modified. A typical resource block used for SRS positioning is shown in FIG. Figure 2A As shown, comb sizes of 4 and 12 OFDM symbols are used. Denote each OFDM symbol x = [x0, ..., x M-1 ], where x m is the sample vector of the mth OFDM symbol. In the absence of PAPR reduction, the PAPR of the first time domain waveform can be expressed as

[0045]

[0046] Here, max{·} represents the maximum operator, |x|| is the absolute value of the complex number x, and N is the number of time domain samples of a specific OFDM symbol. Then, depending on the UE capability, it is necessary to reduce the PAPR in equation (1) to a certain level PAPR level .

[0047] Any PAPR algorithm can be used for PAPR reduction in the UE. However, when the algorithm is applied, it will result in modifying the original SRS symbols. This process can be expressed as

[0048] X modified (a, b) = X original (a,b)+C(a,b) (2)

[0049] where a and b are the subcarrier and OFDM symbol indices, and X modified (a, b) is the modified SRS symbol on the resource element, X original (a, b) is the original SRS symbol on the resource element, and C(a, b) is the distortion caused to the original SRS symbol.Therefore, there is an inherent tradeoff between the required level of PAPR reduction and the degree of frequency domain symbol distortion (compared to the original unmodified SRS constellation).

[0050] The level of distortion can be quantified by a metric defined as

[0051]

[0052] Additionally, reducing the PAPR of a waveform results in reducing the transmit power of the waveform. This can be quantified by the following metric:

[0053]

[0054] It is a measure of how much power is saved compared to the power of the first unmodified SRS waveform.

[0055] To illustrate the process, the above ICF algorithm and example parameters are used for PAPR reduction. Two different distortion levels are defined to evaluate the performance in terms of energy saving and sensing performance. They are defined as medium distortion and extreme distortion, respectively. For a UE uplink transmit power of 20 dBm, the distortion levels in the above equation (3) are given as -13.6 dB and -6.25 dB for these two cases, respectively. A higher value indicates a greater distortion. Therefore, the latter has severe distortion compared to the former.

[0056] Figure 2B Figure 2 shows how PAPR reduction affects frequency domain samples for two distortion levels. The original transmitted symbols of the first waveform are distributed in a circle with the same radius, because they are Zadoff-Chu sequences in this example. However, when medium distortion is applied, the symbols have a circular distribution overall, but with different radii for different symbols. In addition, the average radius of the symbols has been reduced compared to the average radius of the original waveform. This produces a reduced PAPR. Similar behavior is observed for the extreme distortion case, even with a smaller average radius.

[0057] like Figure 2B As shown, increasing distortion (i.e., PAPR reduction) results in a decrease in the average radius of the constellation symbols. Therefore, as shown in equation (4), this reduces the transmission power of the SRS waveform, i.e., increasing distortion to obtain power savings. For the medium distortion and extreme distortion cases, the metric values ​​are 28.0% and 69.7%, respectively.

[0058] Figure 2C The improvement in PAPR is illustrated by the complementary cumulative distribution function CCDF of the PAPR values. On the horizontal axis, the leftmost curve corresponds to extreme distortion, the middle curve corresponds to medium distortion, and the rightmost curve is the original first waveform case. For the original SRS waveform, the 0.1% point corresponds to 5.3dB, while for the medium distortion and extreme distortion cases, it is 2.7dB and 2.5dB, respectively, to give a gain of 2.6dB and 2.8dB. Therefore, a significant reduction in PAPR can be obtained, and the highly nonlinear PA at the UE can be operated in the linear region.

[0059] As described above, a waveform with a lower PAPR is sent to the base station. The base station processes the frequency domain symbols it has received to obtain the necessary estimates for the UE. The base station may not know the modified reduced PAPR uplink frequency domain SRS symbols and may not be able to accurately recreate them. This is because the UE can, in principle, use any PAPR reduction algorithm with different parameters. Therefore, the base station can use the unmodified first waveform SRS symbols for positioning / radar processing of the UE.

[0060] The received uplink symbols and the unmodified SRS symbols can then be used to obtain, for example, a range angle mapping, such as Figure 2D and Figure 2E shown. Figure 2D The range angle map when the original, unmodified first waveform constellation is used at the UE is shown. This clearly shows the location of the UE and the scatterers. Figure 2E The mapping is shown when a moderate distortion is applied in the second waveform. The UE can still be detected using almost the same mapping as in the original case. In simulations, even extreme distortions often lead to very similar conclusions about the location of the UE.

[0061] like Figure 2BAs shown, when PAPR reduction is applied, the uplink power of the waveform is reduced compared to the first unmodified waveform. In addition, the base station is not aware of the modified SRS symbols to be used for uplink processing. However, the UE can still be detected well. Therefore, in practice, reducing the PAPR of the uplink positioning SRS waveform does not necessarily reduce the positioning / sensing performance at all. Since the mapping of moderate distortion is equivalent to the original mapping, it can be applied when the channel conditions are harsh, such as under high mobility conditions. On the other hand, if the channel conditions are known to be good, such as static or low mobility, extreme distortion can be applied, that is, a larger PAPR reduction can be applied from the first waveform to the second waveform.

[0062] On the other hand, in the case where the base station does know the modified uplink SRS waveform, i.e., the second waveform, and uses it for positioning / radar processing. In this case, the UE can still be reliably detected in the case of extreme distortion. However, when medium distortion is used, the performance is essentially the same as when the base station does not know the second waveform in advance. Therefore, the base station does not necessarily need to use modified SRS symbols, and therefore, it does not need to complicate its uplink reception processing and can still use the processing as in conventional SRS transmission without modification. If the UE suggests to the network the PAPR reduction algorithm it intends to use, such as when confirming a PAPR adjustment signal to the network, the base station can know the second waveform. The base station can view the confirmation itself, or the base station can receive from the LMF an indication of which algorithm the UE intends to use, determined by the LMF from the confirmation.

[0063] In general, modifying the SRS waveform to reduce the PAPR helps minimize the PAPR of the transmitted SRS waveform, and the process does not have a substantial negative impact on positioning or sensing performance. The original SRS sequence can also be used at the base station to receive the modified reduced PAPR SRS waveform. Modifying the SRS waveform to reduce the PAPR can reduce the uplink transmit power of the SRS waveform while also reducing the transmission nonlinearity caused by the UE's PA. This is particularly important for capacity reduction and LPHAP devices (where power saving is very important). On the other hand, depending on the channel conditions, the PAPR level can be changed more than once to obtain the desired trade-off between positioning / sensing performance and power saving (i.e., accuracy and energy efficiency).

[0064] Figure 3 An example apparatus capable of supporting at least some embodiments of the present invention is shown. Illustrated is a device 300, which may include, for example, a mobile communication device such as UE 110, 120, or, in applicable parts, Figure 1Base station 130. The device 300 includes a processor 310, which may include, for example, a single-core or multi-core processor, wherein a single-core processor includes one processing core and a multi-core processor includes more than one processing core. The processor 310 may generally include a control device. The processor 310 may include more than one processor. When the processor 310 includes more than one processor, the device 300 may be a distributed device in which the processing of tasks is performed in more than one physical unit. The processor 310 may be a control device. The processing core may include, for example, a Cortex-A8 processing core manufactured by ARM Holdings or a Zen processing core designed by Advanced Micro Devices Corporation. The processing core or processor may be or may include at least one qubit. The processor 310 may include at least one Qualcomm Snapdragon and / or Intel Atom processor. The processor 310 may include at least one application-specific integrated circuit ASIC. The processor 310 may include at least one field programmable gate array FPGA. The processor 310, optionally together with a memory and computer instructions, may be a component for performing method steps in the device 300, such as sending, obtaining, receiving, executing, using, determining, and providing. Processor 310 may be configured, at least in part, by computer instructions to perform actions.

[0065] The processor may include a circuit system, or be constructed as one or more circuit systems, which are configured to perform the various stages of the method according to the embodiments described herein. As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) a hardware-only circuit implementation, such as an implementation in analog and / or digital circuit systems only, and (b) a combination of hardware circuits and software, such as, as applicable: (i) a combination of (multiple) analog and / or digital hardware circuits with software / firmware, and (ii) any portion of (multiple) hardware processors (including (multiple) digital signal processors), software and (multiple) memories with software, which work together to enable the device (such as a UE or base station) to perform various functions), and (c) (multiple) hardware circuits or (multiple) processors, such as (multiple) microprocessors or (multiple) microprocessors, which require software (e.g., firmware) to operate, but when software is not required for operation, the software may not be present.

[0066] This definition of circuitry applies to all uses of the term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of only a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or process and its accompanying software and / or firmware. For example, and if applicable to a particular claim element, the term circuitry also covers a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing or network device.

[0067] Device 300 may include memory 320. Memory 320 may include random access memory and / or permanent memory. Memory 320 may include at least one RAM chip. Memory 320 may be a computer-readable medium. Memory 320 may include, for example, solid-state, magnetic, optical and / or holographic memory. Memory 320 may be at least partially accessible by processor 310. Memory 320 may be at least partially included in processor 310. Memory 320 may be a component for storing information. Memory 320 may include computer instructions that processor 310 is configured to execute. When computer instructions configured to cause processor 310 to perform certain actions are stored in memory 320, and device 300 is generally configured to run under the direction of processor 310 using computer instructions from memory 320, processor 310 and / or at least one of its processing cores may be considered to be configured to perform certain actions described above. Memory 320 may be at least partially included in processor 310. Memory 320 may be at least partially external to device 300, but accessible by device 300. The memory 320 may be transient or non-transitory. The term "non-transitory" as used herein is a limitation on the medium itself (ie, tangible, not a signal), not on data storage persistence (eg, RAM vs. ROM).

[0068] The device 300 may include a transmitter 330. The device 300 may include a receiver 340. The transmitter 330 and the receiver 340 may be configured to transmit and receive information, respectively, according to at least one cellular or non-cellular standard. The transmitter 330 may include more than one transmitter. The receiver 340 may include more than one receiver. The transmitter 330 and / or the receiver 340 may be configured to operate according to, for example, the Global System for Mobile Communications GSM, Wideband Code Division Multiple Access WCDMA, 5G, Long Term Evolution LTE, IS-95, Wireless Local Area Network WLAN, Ethernet, and / or Worldwide Interoperability for Microwave Access WiMAX standards.

[0069] The device 300 may include a near field communication NFC transceiver 350. The NFC transceiver 350 may support at least one NFC technology, such as NFC, Bluetooth, Wibree, or similar technology.

[0070] The device 300 may include a user interface UI 360. The UI 360 may include at least one of a display, a keyboard, a touch screen, a vibrator, a speaker, or a microphone, the vibrator being arranged to signal the user by causing the device 300 to vibrate. The user may be able to operate the device 300 via the UI 360, for example, to accept an incoming phone call, place a phone call or video call, browse the Internet, manage digital files stored in the memory 320 or on a cloud accessible via the transmitter 330 and the receiver 340, or via the NFC transceiver 350, and / or play games.

[0071] The device 300 may include or be arranged to accept a user identity module 370. The user identity module 370 may include, for example, a subscriber identity module SIM card that may be installed in the device 300. The user identity module 370 may include information identifying a subscription of a user of the device 300. The user identity module 370 may include cryptographic information that may be used to verify the identity of the user of the device 300 and / or facilitate encryption of transmitted information and billing of the user of the device 300 for communications achieved via the device 300.

[0072] The processor 310 may be equipped with a transmitter arranged to output information from the processor 310 to other devices included in the device 300 via electrical conductors inside the device 300. Such a transmitter may include a serial bus transmitter arranged to output information to the memory 320 for storage therein, for example, via at least one electrical lead. As an alternative to a serial bus, the transmitter may include a parallel bus transmitter. Similarly, the processor 310 may include a receiver arranged to receive information in the processor 310 from other devices included in the device 300 via electrical conductors inside the device 300. Such a receiver may include a serial bus receiver arranged to receive information from a receiver 340, for example, via at least one electrical lead, for processing in the processor 310. As an alternative to a serial bus, the receiver may include a parallel bus receiver.

[0073] The device 300 may include Figure 3Other devices not shown in the figure. For example, where the device 300 includes a smartphone, it may include at least one digital camera. Some devices 300 may include a rear camera and a front camera, wherein the rear camera may be used for digital photography and the front camera is used for video calls. The device 300 may include a fingerprint sensor that is arranged to at least partially authenticate a user of the device 300. In some embodiments, the device 300 lacks at least one of the above devices. For example, some devices 300 may lack an NFC transceiver 350 and / or a user identity module 370.

[0074] The processor 310, the memory 320, the transmitter 330, the receiver 340, the NFC transceiver 350, the UI 360 and / or the user identity module 370 may be interconnected in a variety of different ways via electrical conductors inside the device 300. For example, each of the above devices may be connected to a main bus inside the device 300, respectively, to allow the devices to exchange information. However, as will be appreciated by those skilled in the art, this is only an example, and according to the embodiment, various ways may be selected to interconnect at least two of the above devices without departing from the scope of the present invention.

[0075] Figure 4 1 shows signaling according to at least some embodiments of the present invention. On the vertical axis, from left to right, UE 110, base station 130, neighboring base stations, and LMF on the right are arranged. Time passes from top to bottom.

[0076] In stage 410, a positioning procedure is performed at least in part using the first waveform. As described above, the UE may retrieve or generate the first waveform based on, for example, a preconfigured list, radio channel conditions, and / or industry standards. In stage 420, the LMF determines a PAPR adjustment signal that specifies how much the UE may reduce the PAPR of the first waveform for the second waveform based on the capabilities of the UE in, for example, power, bandwidth, and mobility. Stage 410 includes an SRS transmission from the UE using the first waveform.

[0077] In stage 430, the LMF provides a PAPR adjustment signal to the UE. In optional stage 440, the UE acknowledges the PAPR adjustment signal. In some embodiments, the message of stage 440 informs the base station of the adjusted second waveform with reduced PAPR that the UE intends to use so that the base station 130 can use it when receiving the SRS using the second waveform. In some embodiments, the message of stage 440 informs the base station of the algorithm that the UE will use when reducing the PAPR of the first waveform. This will also help the base station receive the SRS using the second waveform.

[0078] In stage 450, the UE obtains a second waveform having a lower PAPR than the first waveform from the first waveform based on the PAPR adjustment signal of stage 430. In the case where stage 440 is present, stages 450 and 440 may occur sequentially or at least partially simultaneously.

[0079] In stage 460, UE 110 transmits an SRS using the second waveform, which is received by two base stations. It is worth noting that, instead of base stations, these units may be transmission / reception points TRP. Finally, in stage 470, base station 130 performs positioning or radar processing of the user equipment based on frequency domain symbols of both the sounding reference signal using the first waveform received in base station 130 and the sounding reference signal using the second waveform received in base station 130. Stages 410 to 470 may be included in a positioning process.

[0080] Figure 5 is a flow chart of a method according to at least some embodiments of the present invention. The stages of the method shown may be performed in, for example, device 110, an auxiliary device or a personal computer, or in a control device configured to control its functions when installed therein.

[0081] Stage 510 includes sending a first sounding reference signal from the device to the network. Stage 520 includes: obtaining a second sounding reference signal having a lower PAPR than the first sounding reference signal from the first sounding reference signal based on a peak-to-average power ratio (PAPR) adjustment signal received in the device from the network. Finally, stage 530 includes sending a second sounding reference signal to the network.

[0082] It should be understood that the disclosed embodiments of the present invention are not limited to the specific structures, process steps or materials disclosed herein, but are extended to their equivalents recognized by those of ordinary skill in the relevant art. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not intended to be limiting.

[0083] Throughout the specification, reference to an embodiment or embodiments indicates that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present invention. Thus, the phrases "in one embodiment" or "in an embodiment" that appear in various places throughout the specification do not necessarily all refer to the same embodiment. Where terms such as approximately or substantially are used to reference values, the exact value is also disclosed.

[0084] As used herein, for convenience, multiple items, structural elements, constituent elements and / or materials can be presented in a public list. However, these lists should be understood as each member in the list is individually identified as a separate and unique member. Therefore, any individual member on such a list should not be interpreted as being in fact equivalent to any other member on the same list based solely on its existence in a common group (without contrary signs). In addition, various embodiments and examples of the present invention and alternatives to its various components can be mentioned in this article. It should be understood that such embodiments, examples and alternatives should not be interpreted as equivalents in fact to each other, but should be regarded as independent and autonomous representations of the present invention.

[0085] In addition, the described features, structures or characteristics can be combined in any suitable manner in one or more embodiments. In the foregoing description, many specific details, such as examples of length, width, shape, etc., are provided to provide a comprehensive understanding of embodiments of the present invention. However, those skilled in the relevant art will recognize that the present invention can be practiced without one or more specific details, or practiced using other methods, components, materials, etc. In other cases, well-known structures, materials or operations are not shown or described in detail to avoid confusing various aspects of the present invention.

[0086] Although the above embodiments illustrate the principles of the present invention in one or more specific applications, it is obvious that those skilled in the art can make many modifications to the form, usage and implementation details without departing from the principles and concepts of the present invention without exercising creativity. Therefore, the present invention is not limited unless it is limited by the following claims.

[0087] In this document, the verbs "to compose" and "to include" are used as open limitations, neither excluding nor requiring the presence of unrecited features. Unless explicitly stated otherwise, the features recited in the dependent claims are mutually freely combinable. Furthermore, it should be understood that the use of "a" or "an" (i.e. the singular) throughout this document does not exclude a plurality.

[0088] As used herein, “at least one of: ” and “at least one of ” and similar expressions (wherein a list of two or more elements is connected by “and” or “or”) refer to at least any one of these elements, or at least any two or more of these elements, or at least all of the elements.

[0089] Industrial Applicability

[0090] At least some embodiments of the present invention have industrial applications in managing cellular communications.

[0091] List of abbreviations

[0092] 3GPP: Third Generation Partnership Project

[0093] LPHAP: Low Power High Accuracy Positioning

[0094] OFDM: Orthogonal Frequency Division Multiplexing

[0095] PA: Power Amplifier

[0096] UE: User Equipment

[0097] Citation List

[0098] "On the Optimization of Iterative Clipping and Filtering for PAPRReduction in OFDM Systems" by K. Anoh and C. Tanriover, IEEE Access, June 2017.

[0099] "PAPR reduction of OFDM signals using harmony search algorithm", author EMKermani et al., IEEE 2011, 18th International Conference on Telecommunications, May 2011.

Claims

1. An apparatus for communication, comprising at least one processing core and at least one memory storing instructions, wherein the instructions, when executed by the at least one processor core, cause the apparatus to at least: -sending a first sounding reference signal to the network; - based on a peak-to-average power ratio (PAPR) adjustment signal received in the device from the network, obtaining a second sounding reference signal having a lower PAPR than the first sounding reference signal from the first sounding reference signal, and - sending the second sounding reference signal to the network.

2. The apparatus of claim 1, wherein the apparatus is configured to send an acknowledgement to the network that the PAPR adjustment signal has been received.

3. The apparatus according to claim 1 or 2, wherein the apparatus is configured to receive the PAPR adjustment signal from a location management function in a core network of the network, or from a radio access network of the network.

4. The device according to any one of claims 1 to 3, further configured to: receiving a second PAPR adjustment signal from the network, based on the second PAPR adjustment signal, obtaining a third sounding reference signal from the first sounding reference signal or the second sounding reference signal, wherein the third sounding reference signal has a lower PAPR than the second sounding reference signal, and The third sounding reference signal is sent to the network. 5 . The apparatus according to claim 1 , wherein the apparatus is configured to perform the acquisition of the second sounding reference signal from the first sounding reference signal using an iterative clipping and filtering (ICF) algorithm.

6. The apparatus according to any one of claims 1 to 5, wherein the apparatus is configured to: send the first sounding reference signal using a first waveform, and transmit the second sounding reference signal using a second waveform, wherein the second waveform has a lower PAPR than the first waveform.

7. An apparatus for communication, comprising at least one processing core and at least one memory storing instructions, the instructions, when executed by the at least one processor core, causing the apparatus to at least: - first receiving a first sounding reference signal from a user equipment and then receiving a second sounding reference signal, wherein the second sounding reference signal has a lower peak-to-average power ratio (PAPR) than the first sounding reference signal, and - In a positioning or radar process of the user equipment, using frequency domain symbols of both the first sounding reference signal and the second sounding reference signal.

8. A method for communication, comprising: -sending a first sounding reference signal from the device to the network; - based on a peak-to-average power ratio (PAPR) adjustment signal received in the device from the network, obtaining a second sounding reference signal having a lower PAPR than the first sounding reference signal from the first sounding reference signal, and - sending the second sounding reference signal to the network.

9. The method according to claim 8, wherein the method comprises: An acknowledgement is sent to the network that the PAPR adjustment signal has been received.

10. The method according to any one of claims 8 to 9, further comprising: receiving a second PAPR adjustment signal from the network, deriving a third sounding reference signal from the first sounding reference signal or the second sounding reference signal based on the second PAPR adjustment signal, wherein the third sounding reference signal has a lower PAPR than the second sounding reference signal, and The third sounding reference signal is sent to the network.

Images