WO2021022531A1

WO2021022531A1 - Device, method, apparatus and computer readable medium for detecting cross link interference

Info

Publication number: WO2021022531A1
Application number: PCT/CN2019/099689
Authority: WO
Inventors: Lei Du; Axel Mueller; Lars Dalsgaard; Riikka NURMINEN
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2019-08-07
Filing date: 2019-08-07
Publication date: 2021-02-11
Also published as: CN114208253B; CN114208253A

Abstract

Embodiments of the present disclosure relate to a device, method, apparatus and computer readable medium for detecting Cross Link Interference. In some embodiments, a first device receives a measurement configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports used by a third device for transmission of the sounding reference signals. The first device receives the sounding reference signals from the third device based on the configuration. The first device determines an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports. The first device transmits the estimation of the cross link interference to the second device.

Description

DEVICE, METHOD, APPARATUS AND COMPUTER READABLE MEDIUM FOR DETECTING CROSS LINK INTERFERENCE

FIELD

Embodiments of the present disclosure generally relate to the field of communications, and in particular, to a device, method, apparatus and computer readable medium for detecting Cross Link Interference (CLI) .

BACKGROUND

The New Radio (NR) is designed to support paired and unpaired spectrum where the transmission direction of most time resources can be dynamically changed. Downlink (DL) and uplink (UL) transmission directions at least for data can be dynamically assigned on a per-slot basis at least in a time division multiplexing (TDM) manner. This kind of duplexing flexibility offers better user throughput, but also comes with the potential cost of undesirable CLI.

During Rel 15 NR work item, it was agreed to introduce UE-to-UE measurement for CLI mitigation, but it could not be specified because the work has been deprioritized. In Rel 16, a work item was approved to study CLI mitigation techniques to support flexible resource adaptation. One of the objectives is to specify CLI measurements and reporting at a UE including CLI-Received Signal Strength Indicator (RSSI) and CLI Sounding Reference Signal-Reference Signal Received Power (SRS-RSRP) . However, how to measure the SRS-RSRP and report a reasonable value with the SRS-RSRP measurement configuration still needs to be discussed.

SUMMARY

In general, example embodiments of the present disclosure provide a solution for detecting CLI.

In a first aspect, there is provided a first device. The first device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the first device to: receive a configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals; receive the sounding reference signals from the third device based on the configuration; determine an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports; and transmit the estimation of the cross link interference to the second device.

In a second aspect, there is provided a first device. The first device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the first device to: receive a configuration for sounding reference signals from a second device; receive the sounding reference signals from a third device based on the configuration; determine an estimation of cross link interference from the third device based on the received sounding reference signals and a preconfigured threshold number of the antenna ports; and transmit the estimation of the cross link interference to the second device.

In a third aspect, there is provided a first device. The first device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the first device to: receive a resource configuration for sounding reference signals from a second device, the resource configuration at least indicating a resource on which the sounding reference signals are to be received; receive sounding reference signals from at least one of a third device and a fourth device based on the resource configuration; determine an estimation of cross link interference from the at least one of the third and fourth devices based on the received sounding reference signals and predetermined configurations for the sounding reference signals; and transmit the estimation of the cross link interference to the second device.

In a fourth aspect, there is provided a second device. The second device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the second device to: transmit a configuration for sounding reference signals to a first device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals; and receive, from the first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals and the number of the antenna ports.

In a fifth aspect, there is provided a second device. The second device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the second device to: receive, from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern; receive, from a first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals; and detect the third device based on the change and the estimation of cross link interference.

In a sixth aspect, there is provided a second device. The second device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the second device to: receive, from a fifth device, an indication of the number of antenna ports to be used by a third device for transmission of sounding reference signals; receive, from the first device, an indication of a power level of one of the sounding reference signals from one of the antenna ports; and determine an estimation of cross link interference from the third device to the first device by increasing the power level based on the number of antenna ports.

In a seventh aspect, there is provided a third device. The third device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the third device to: receive from a fifth device a command indicating the third device to increase transmission power levels of sounding reference signals; increase the transmission power levels based on the number of antenna ports to be used by the third device for transmission of the sounding reference signals; and transmit the sounding reference signals with the increased transmission power levels to a first device for estimation of cross link interference from the third device to the first device.

In an eighth aspect, there is provided a method implemented at a device. The method comprises: receiving, at a first device, a configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals; receiving the sounding reference signals from the third device based on the configuration; determining an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports; and transmitting the estimation of the cross link interference to the second device.

In a ninth aspect, there is provided a method implemented at a device. The method comprises: receiving, at a first device, a configuration for sounding reference signals from a second device; receiving the sounding reference signals from a third device based on the configuration; determining an estimation of cross link interference from the third device based on the received sounding reference signals and a preconfigured threshold number of the antenna ports; and transmitting the estimation of the cross link interference to the second device.

In a tenth aspect, there is provided a method implemented at a device. The method comprises: receiving, at a first device, a resource configuration for sounding reference signals from a second device, the resource configuration at least indicating a resource on which the sounding reference signals are to be received; receiving sounding reference signals from at least one of a third device and a fourth device based on the resource configuration; determining an estimation of cross link interference from the at least one of the third and fourth devices based on the received sounding reference signals and predetermined configurations for the sounding reference signals; and transmitting the estimation of the cross link interference to the second device.

In an eleventh aspect, there is provided a method implemented at a device. The method comprises: transmitting, at a second device, a configuration for sounding reference signals to a first device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals; and receiving, from the first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals and the number of the antenna ports.

In a twelfth aspect, there is provided a method implemented at a device. The method comprises: receiving, at a second device and from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern; receiving, from a first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals; and detecting the third device based on the change and the estimation of cross link interference.

In a thirteenth aspect, there is provided a method implemented at a device. The method comprises: receiving, at a second device and from a fifth device, an indication of the number of antenna ports to be used by a third device for transmission of sounding reference signals; receiving, from the first device, an indication of a power level of one of the sounding reference signals from one of the antenna ports; and determining an estimation of cross link interference from the third device to the first device by increasing the power level based on the number of antenna ports.

In a fourteenth aspect, there is provided a method implemented at a device. The method comprises: receiving, at a third device and from a fifth device a command indicating the third device to increase transmission power levels of sounding reference signals; increasing the transmission power levels based on the number of antenna ports to be used by the third device for transmission of the sounding reference signals; and transmitting the sounding reference signals with the increased transmission power levels to a first device for estimation of cross link interference from the third device to the first device.

In a fifteenth aspect, there is provided an apparatus comprising: means for receiving, at a first device, a configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals; means for receiving the sounding reference signals from the third device based on the configuration; means for determining an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports; and means for transmitting the estimation of the cross link interference to the second device.

In a sixteenth aspect, there is provided an apparatus comprising: means for receiving, at a first device, a configuration for sounding reference signals from a second device; means for receiving the sounding reference signals from a third device based on the configuration; means for determining an estimation of cross link interference from the third device based on the received sounding reference signals and a preconfigured threshold number of the antenna ports; and means for transmitting the estimation of the cross link interference to the second device.

In a seventeenth aspect, there is provided an apparatus comprising: means for receiving, at a first device, a resource configuration for sounding reference signals from a second device, the resource configuration at least indicating a resource on which the sounding reference signals are to be received; means for receiving sounding reference signals from at least one of a third device and a fourth device based on the resource configuration; means for determining an estimation of cross link interference from the at least one of the third and fourth devices based on the received sounding reference signals and predetermined configurations for the sounding reference signals; and means for transmitting the estimation of the cross link interference to the second device.

In an eighteenth aspect, there is provided an apparatus comprising: means for transmitting, at a second device, a configuration for sounding reference signals to a first device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals; and means for receiving, from the first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals and the number of the antenna ports.

In a nineteenth aspect, there is provided an apparatus comprising: means for transmitting, at a second device, a first configuration and a second configuration to a first device, the first configuration used for at least one first sounding reference signal to be transmitted from a third device to the first device, the second configuration used for at least one second sounding reference signal to be transmitted from a fourth device to the first device, the second configuration different from the first configuration; means for receiving, from the first device, a first estimation of cross link interference from the third device to the first device, the first estimation being determined based on the first sounding reference signal and the first configuration; and means for receiving, from the first device, a second estimation of cross link interference from the fourth device to the first device, the second estimation being determined based on the second sounding reference signal and the second configuration.

In a twentieth aspect, there is provided an apparatus comprising: means for receiving, at a second device and from a fifth device, an indication of the number of antenna ports to be used by a third device for transmission of sounding reference signals; means for receiving, from the first device, an indication of a power level of one of the sounding reference signals from one of the antenna ports; and means for determining an estimation of cross link interference from the third device to the first device by increasing the power level based on the number of antenna ports.

In a twenty-first aspect, there is provided an apparatus comprising: means for receiving, at a third device and from a fifth device a command indicating the third device to increase transmission power levels of sounding reference signals; means for increasing the transmission power levels based on the number of antenna ports to be used by the third device for transmission of the sounding reference signals; and means for transmitting the sounding reference signals with the increased transmission power levels to a first device for estimation of cross link interference from the third device to the first device.

In a twenty-second aspect, there is provided a third device. The third device comprises at least one processor; and at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the third device to: receive, from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern; transmit the sounding reference signals based on the first and second patterns, and the change.

In a twenty-third aspect, there is provided an apparatus comprising: means for receiving, at a third device and from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern; means for transmitting the sounding reference signals based on the first and second patterns, and the change.

In a twenty-fourth aspect, there is provided a computer readable medium comprising a computer program for causing an apparatus to perform at least the method according to one of the above eighth aspect to fourteenth aspect.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Some example embodiments will now be described with reference to the accompanying drawings, where:

Fig. 1 shows an example communication network in which embodiments of the present disclosure may be implemented;

Fig. 2 shows an idealised example of correlation peaks of SRS according to some example embodiments of the present disclosure;

Fig. 3 shows an example timing scenario for CLI SRS measurement according to some example embodiments of the present disclosure;

Fig. 4 shows an example of wrong correlation peak detection due to timing error and wraparound of a cyclic shift;

Fig. 5A shows an example of correlation peaks detected by a device;

Fig. 5B shows another example of correlation peaks detected by a device;

Fig. 5C shows an example of interlacing correlation peaks of SRS from two devices;

Fig. 5D shows an example of overlapping correlation peaks of SRS from two devices;

Fig. 6 shows a signaling chart illustrating a process for detecting CLI according to some example embodiments of the present disclosure;

Fig. 7 shows a signaling chart illustrating a process for detecting CLI according to other example embodiments of the present disclosure;

Fig. 8 shows a signaling chart illustrating a process for detecting CLI according to still other example embodiments of the present disclosure;

Fig. 9 shows a signaling chart illustrating a process for detecting CLI according to yet other example embodiments of the present disclosure;

Fig. 10 shows a signaling chart illustrating a process for detecting CLI according still other example embodiments of the present disclosure;

Fig. 11 shows a signaling chart illustrating a process for detecting CLI according to yet other example embodiments of the present disclosure;

Fig. 12 shows a flowchart of a method implemented at a device in accordance with some example embodiments of the present disclosure;

Fig. 13 shows a flowchart of a method implemented at a device in accordance with some example embodiments of the present disclosure;

Fig. 14 shows a flowchart of a method implemented at a device in accordance with some example embodiments of the present disclosure;

Fig. 15 shows a flowchart of a method implemented at a device in accordance with some example embodiments of the present disclosure;

Fig. 16 shows a flowchart of a method implemented at a device in accordance with some example embodiments of the present disclosure;

Fig. 17 shows a flowchart of a method implemented at a device in accordance with some example embodiments of the present disclosure;

Fig. 18 shows a flowchart of a method implemented at a device in accordance with some example embodiments of the present disclosure;

Fig. 19 shows a flowchart of a method implemented at a device in accordance with some example embodiments of the present disclosure;

Fig. 20 illustrates a simplified block diagram of an apparatus that is suitable for implementing some other embodiments of the present disclosure; and

Fig. 21 illustrates a block diagram of an example computer readable medium in accordance with some example embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an embodiment, ” “an example embodiment, ” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an example embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

As used in this application, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable) :

(i) a combination of analog and/or digital hardware circuit (s) with software/firmware and

(ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

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

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as fifth generation (5G) systems, Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the future fifth generation (5G) new radio (NR) communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a NR Next Generation NodeB (gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , a remote radio head (RRH) , a relay, a low power node such as a femto, a pico, and so forth, depending on the applied terminology and technology. An RAN split architecture comprises a gNB-CU (Centralized unit, hosting RRC, SDAP and PDCP) controlling a plurality of gNB-DUs (Distributed unit, hosting RLC, MAC and PHY) .

The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE) , a Subscriber Station (SS) , a Portable Subscriber Station, a Mobile Station (MS) , or an Access Terminal (AT) . The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA) , portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , USB dongles, smart devices, wireless customer-premises equipment (CPE) , an Internet of Things (IoT) device, a watch or other wearable, a head-mounted display (HMD) , a vehicle, a drone, a medical device and applications (e.g., remote surgery) , an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts) , a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

Although functionalities described herein can be performed, in various example embodiments, in a fixed and/or a wireless network node may, in other example embodiments, functionalities may be implemented in a user equipment apparatus (such as a cell phone or tablet computer or laptop computer or desktop computer or mobile IoT device or fixed IoT device) . This user equipment apparatus can, for example, be furnished with corresponding capabilities as described in connection with the fixed and/or the wireless network node (s) , as appropriate. The user equipment apparatus may be the user equipment and/or or a control device, such as a chipset or processor, configured to control the user equipment when installed therein. Examples of such functionalities include the bootstrapping server function and/or the home subscriber server, which may be implemented in the user equipment apparatus by providing the user equipment apparatus with software configured to cause the user equipment apparatus to perform from the point of view of these functions/nodes.

Fig. 1 shows an example communication network 100 in which embodiments of the present disclosure can be implemented. The communication network 100 comprises a first device 110 which is served by a second device 120, a third device 130 and a fourth device 140 which are served by a fifth device 150. The fifth device 150 provides a neighbor cell of a cell provided by the second device 120. In this example, the first device 110, the third device 130 and the fourth device 140 are illustrated as terminal devices, and the second device 120 and the fifth device 150 are illustrated as network devices. It is to be understood that numbers of the first, second, third, fourth and fifth devices are given for the purpose of illustration without suggesting any limitations to the present disclosure. The communication network 100 may include any suitable number of the first, second, third, fourth and fifth devices adapted for implementing implementations of the present disclosure.

The first device 110, the third device 130 and the fourth device 140 can communicate with each other via the second device 120 and the fifth device 150. The communication may follow any suitable communication standards or protocols such as Universal Mobile Telecommunications System (UMTS) , long term evolution (LTE) , LTE-Advanced (LTE-A) , the fifth generation (5G) NR, Wireless Fidelity (Wi-Fi) and Worldwide Interoperability for Microwave Access (WiMAX) standards, and employs any suitable communication technologies, including, for example, Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Division Multiplexing (OFDM) , time division multiplexing (TDM) , frequency division multiplexing (FDM) , code division multiplexing (CDM) , Bluetooth, ZigBee, and machine type communication (MTC) , enhanced mobile broadband (eMBB) , massive machine type communication (mMTC) and ultra-reliable low latency communication (uRLLC) technologies.

DL transmission of the first device 110 may be interfered by UL transmission of the third device 130. In some cases, DL transmission of the first device 110 may be also interfered by UL transmission of the fourth device 140. Thus, the first device 110 may be referred to as a victim device, and the third device 130 and the fourth device 140 may be referred to as aggressor devices. The interference caused by the UL transmission of the third device 130 or the UL transmission of the fourth device 140 to the DL transmission of the first device 110 is referred to as CLI. The first device 110 determines an estimation of the CLI from the third device 130 by measuring SRS or overall power transmitted from the third device 130.

In some embodiments, the first device 110 may measure Reference Signal Received Power (RSRP) of the SRS transmitted from the third device 130 so as to determine the estimation of the CLI. In other embodiments, the first device 110 may measure Received Signal Strength Indicator (RSSI) so as to determine the estimation of the CLI.

Upon determining the estimation of the CLI, the first device 110 transmits the estimation of the CLI to the second device 120. Upon receiving the estimation of the CLI, the second device 120 may inform the fifth device 150 that a resource for the UL transmission of the third device 130 may be adjusted so as to mitigate the CLI. Similarly, the first device 110 may determine and transmit to the second device 120 an estimation of CLI from the fourth device 140 for mitigation of the CLI.

Examples of SRS may include, but are not limited to, Generalized Chirp Like (GCL) sequences, Constant Amplitude Zero Auto-Correlation (CAZAC) sequences, low PARA CAZAC sequences, filtered sinusoids, and pseudo-random (e.g., Gold) sequences. For example, the GCL sequences may comprise a GCL base sequence and cyclically shifted GCL sequences that are generated by cyclically shifting the GCL base sequence. Similarly, the CAZAC sequences may comprise a CAZAC base sequence and cyclically shifted CAZAC sequences that are generated by cyclically shifting the CAZAC base sequence.

Antenna ports of an aggressor device for transmission of SRS can be orthogonally multiplexed in time (different symbols) , frequency (BW, hopping, comb) , and code (cyclic shift) domain. In the following, impact of system imperfections on the cyclic shift multiplexing will be discussed.

In some embodiments, a victim device may detect the SRS by using a correlation receiver, which will be described later. The correlation function with the base sequences is computed after resource element (RE) demapping, which is often called sequence/frequency domain and then transformed to time domain, before time/sample based windowing is used to detect the cyclic shift of the base sequences. This is a computationally efficient method to find correlations for all cyclic shifts and shows directly how timing imperfections affect the correlation receiver. The SRS sequence is “loaded” into the REs provided by OFDM, and the OFDM waveform is then affected by transmission and reception imperfections. In such embodiments, some correlation peaks of SRS over samples in time domain may be obtained. Fig. 2 shows an idealised example of correlation peaks of SRS according to some example embodiments of the present disclosure.

In a perfect system, each cyclic shift (CS) of an SRS sequence is detected in the center of its corresponding detection window, as a single well defined peak of area proportional to the received energy. Each detection window is of width T_SRS_Symbol/Nr_cyclic_shifts, where T_SRS_Symbol represents the length in seconds or samples of the symbol (s) carrying the SRS sequence, and Nr_cyclic_shifts represents the number of the cyclic_shifts, which is a function of the configured CombOffset in SRS configuration.

If a correlation peak is detected in a detection/filter/observation window pertaining to a wrong cyclic shift, it is taken as being caused by a different SRS configuration, e.g., a different CS. If all possible SRS configurations are known, then leaving gaps in the used CSs will allow for correct SRS detection over a larger observation window.

Peaks pertaining to cyclic shifts of the SRS sequences “wrap around” with timing shifts. That is, “later” of CS=0 is CS=1 and “earlier” of it is CS=7 in the example of Fig. 2. If a drift of a cyclic shift is caused by timing error, wrap around is still applicable, albeit at a reduced peak height, since the detection is starting to lose SRS energy due to symbol misalignment. A total detection timing error of less than a Cyclic Prefix (CP) length does not shift the peak positions.

In some embodiments, the cyclic shift α _i for antenna port p _i is given as

where

is contained in the higher layer parameter transmissionComb. The maximum number of cyclic shifts is

if K _TC=4 and

if K _TC=2.

In some embodiments, antenna ports of an aggressor device may be mapped to cyclic shifts on a specific comb, which results in respective SRS correlation peaks for the cyclically shifted SRS sequence. For example, mapping between numbers of the antenna ports and the cyclic shifts may be as shown in Table 1:

Table 1

In Table 1,

represents a position of a correlation peak for the first antenna port having a number of 1000. The other antenna ports are allocated to cyclic shift numbers that are relative to the first antenna port. In the example of Fig. 2, as defined in in TS 38.331, the first port having a number of 1000 will be where it is configured to be (in transmissionComb information element) and the second port having a number of 1001 will be exactly two “cyclic shift numbers” higher; with wraparound (i.e., mod 8 for the case of

) .

With respect to RSRP measurements of the SRS, the following agreements have been achieved:

· Measurement resource for SRS-RSRP measurement is configured by SRS resource configuration.

· For SRS transmission for SRS-RSRP measurement purpose, no new SRS resource set usage is introduced.

· In order to perform SRS transmission for CLI measurement, The TA value applied to the corresponding UL symbol is the same as the latest TA for regular UL symbols transmitted to the gNB.

· For SRS-RSRP measurement, the UE is not required to perform time tracking or time adjustment other than a constant offset relative to its own DL timing. The constant offset is derived by UE implementation.

· QCL assumption on SRS-RSRP interference measurement resources is up to UE implementation.

The parameters for SRS-RSRP measurement configuration are suggested as in the following Table 2.

Table 2

In the following, measurement inaccuracy caused by the SRS-RSRP measurement configuration will be discussed.

A. Inconsistent port configuration between aggressor device and victim device

Table 2 shows some parameters of CLI SRS-RSRP measurement configuration. The IE nrofSRS-Ports represents the number of antenna ports that is assumed to be used for transmission of SRS. As shown in Table 2, it has been suggested that the value of nrofSRS-Ports is equal to 1. This means that a victim device will always assume that the SRS is transmitted from the aggressor device over single antenna port. However, as described above, SRS may be transmitted from the aggressor device over one or multiple antenna ports based on the nrofSRS-Ports in the following UE specific radio resource control SRS configuration :

nrofSRS-Ports ENUMERATED {port1, ports2, ports4}

In case where multiple antenna ports are configured for an aggressor device, the aggressor device splits the transmit power on active UL Bandwidth Part (BWP) of the carrier equally across the configured antenna ports for transmission of SRS.

At the receiving side, the victim device is supposed to detect a series of “correlation peaks” by using a correlation receiver, assuming the same behavior as a network device. For example, in the example of Fig. 2, it is assumed that four antenna ports of an aggressor device are used for transmission of SRS. Thus, without timing error between a victim device and the aggressor device, four

correlation peaks

201, 202, 203 and 204 may be detected. Each of the four

correlation peaks areas

201, 202, 203 and 204 are representative of the received power of the SRS.

However, conventionally, when the victim device performs SRS-RSRP measurement for CLI mitigation, as indicated by “nrofSRS-Ports” in Table 2, only single antenna port reception is configured or assumed irrespective of how many antenna ports over which the SRS is transmitted from the aggressor device. That is, there exists the inconsistency between the applied nrofSRS-antenna ports configuration at the aggressor device and the SRS-RSRP measurement configuration at the victim device.

Based on the SRS-RSRP measurement configuration, as shown in Table 2, the victim device will count one of the four correlation peaks as the SRS-RSRP measurement result because the victim device assumes single antenna port SRS transmission. This reflects only approximately 1/nrofSRS-Ports of the total transmit power level of the SRS that should have been detected by the victim device. Such an inaccurate SRS-RSRP measurement result may be too weak to trigger the measurement report and thus cannot reflect the real CLI status.

B. Timing Error impact to SRS-RSRP measurement accuracy

Fig. 3 shows an example timing scenario 300 for CLI SRS measurement according to some example embodiments of the present disclosure. The timing scenario 300 involves seven Orthogonal Frequency Division Multiplexing (OFDM) symbols, where Ts represents a symbol length.

In the timing scenario 300, at a time instant 310, gNB1 serving an aggressor device is supposed to receive the SRS from the aggressor device. At a time instant 320, the aggressor device transmits the SRS with the Timing Advance (TA) ahead of the DL reference timing of gNB1. A time difference between the time instant 310 and the time instant 320 is equal to TA_1/2+TA_OFFSET, where TA_1 represents the timing advance used by the aggressor device, TA_OFFSET is defined in TS 38.133 table 7.1.2-2, which is incorporated herein in its entirety. At a time instant 330, gNB2 serving a victim device requests the victim device to measure the RSRP of the SRS transmitted by the aggressor device. At a time instant 340, the SRS transmitted by the aggressor device arrives at the victim device. At a time instant 350, the victim device measures the SRS transmitted by the aggressor device. A time difference between the time instant 320 and the time instant 340 is equal to PD_12, where PD_12 represents the propagation delay from the aggressor device to the victim device.

Based on the RAN1 agreements on timing, the victim device has no information about the timing including the timing advance (TA) used by the aggressor device for transmission of SRS from the aggressor device. Therefore, a timing error (TE) uncertainty arises between the time instant 340 when the SRS arrives at the victim device relative to the time instant 350 when the victim device measures the SRS, including measuring the configured SRS resources.

The TE between the time instant 340 and the time instant 350 is equal to TA_2/2+TA_1/2+TA_OFFSET -PD_12±CP_sync_err, where TA_2 represents the timing advance used by the victim device, CP_sync_err represents cell phase synchronization accuracy for TDD defined for any pair of cells on the same frequency with overlapping coverage areas as defined in section 7.4 of TS 38.133, which is incorporated herein in its entirety. A difference 352 between the gNB2 DL timing and the reception timing at the victim device is equal to TA_2/2.

Considering the TE, the SRS measurement window is shifted by the TE. As the victim device measures single port, it may either measure no correlation peaks or the correlation peaks from other ports due to the TE. Fig. 4 shows an example 400 of wrong correlation peak detection due to timing error and wraparound of a cyclic shift.

As shown Fig. 4, the victim device should have measured the SRS 410 over configured single port according to the CLI SRS-RSRP measurement configuration. However, the victim device measures the left-most correlation peak 420 because the SRS arrival and the “peaks” are shifted due to TE. The victim device may not be able to measure or rather correctly relate/assign the correlation peak of the SRS corresponding to the configured port due to the time-shifted ” peaks” .

C. Mix of SRS correlation peaks in case of multiple aggressor devices

The previously discussed problems become even more pressing in a multiple aggressor devices scenario.

Fig. 5A shows an example 500 of correlation peaks transmitted by the first aggressor device and Fig. 5B shows an example 510 of correlation peaks transmitted by the second aggressor device. In the example 500, the first aggressor device is configured to transmit SRS over two antenna ports. The correlation peaks 501 and 502 are supposed to appear at victim device. In the example 510, the second aggressor device is configured to transmit SRS over two antenna ports. The correlation peaks 511 and 512 are supposed to appear at victim device. The SRS of first and second aggressor devices are configured to be transmitted on the exact same time, frequency, or base sequence resources, just with different cyclic shifts. This is expected to be a common occurrence, once UL/DL reciprocity precoding becomes prevalent.

The SRS from the first aggressor device and the SRS from the second aggressor device are received with different TEs at the victim device, which may causes shifted, drifted, or overlapped correlation peaks. Fig. 5C shows an example 520 of interlacing correlation peaks of the SRSs from two aggressor devices. Compared with the correlation peaks 501 and 502 in Fig. 5A, correlation peaks 521 and 522 in Fig. 5C are shifted by 2 cyclic shifts. Compared with the correlation peaks 511 and 512 in Fig. 5B, correlation peaks 523 and 524 are shifted by 3.5 cyclic shifts.

Fig. 5D shows an example 530 of overlapping correlation peaks of SRSs from two aggressor devices. Compared with the correlation peaks 501 and 502 in Fig. 5A, correlation peaks 531 and 532 in Fig. 5D are shifted by 2 cyclic shifts. Compared with the correlation peaks 511 and 512 in Fig. 5B, correlation peaks 533 and 534 are shifted by -2.5 cyclic shifts. Thus, the correlation peak 531 is overlapped with the correlation peak 533, and the correlation peak 532 is overlapped with the correlation peak 534.

Even worse examples are possible, especially when the initial CS configuration was not symmetric, or the number of antenna ports was not equal, or there were unknown aggressors.

In any of the above examples, it is impossible for the victim device to know which of the two aggressor devices has caused the interference. Hence, neither the victim device nor the gNBs can decide, which aggressor should be reconfigured. The only solution is to reschedule all known possible aggressor devices.

In addition, if the aggressor devices come from the same aggressor cell, then they will most likely be using the same SRS base sequence (i.e., the same “u/v configuration” ) and the different TEs will cause their cyclic shifts to drift with respect to each other.

Typically, all devices in a cell are given the same SRS sequence group number (u = {0, ..., 29} ) and are then separated or orthogonalized with each other using the other methods (time, frequency, CS) . Different sequence groups are allocated between cells in the cell planning process. As there are only 30 groups, it does not make sense to use different groups in the same cell, because then there is a large chance of interference to normal SRS measurements from one of the neighboring cells.

To summarize, as a single port is configured for CLI measurement, the following potential issues are observed:

(1) The measured result only reflects approximately 1/2 or 1/4 of the SRS-RSRP, not the real CLI status at victim UE.

(2) The SRS over configured port may be missed so that inaccurate CLI measurement results are reported.

(3) In case multiple SRS signals arrive within the measured SRS source, for example due to timing errors, the measured result may be one of the mixed SRS peaks and cannot reflect the real SRS-RSRP level.

(4) In case multiple SRS signals from multiple aggressor UEs arrives in the same measurement period, the peaks might be matched to the wrong UE and the CLI feedback is damaging to system performance.

In order to, at least in part solve above and other potential problems, example embodiments of the present disclosure provide a plurality of solutions for detecting CLI. In one solution, a victim device is informed by the network of the number of antenna ports used by an aggressor device for SRS transmission. The victim device measures SRS-RSRP over all the antenna ports and obtains CLI measurement results accordingly. Thus, accurate CLI measurement results may be obtained and reported.

Principle and implementations of the present disclosure will be described in detail below with reference to Figs. 6 to 11. Fig. 6 shows a signaling chart illustrating a process 600 for detecting CLI according to some example embodiments of the present disclosure. For the purpose of discussion, the process 600 will be described with reference to Fig. 1. The process 600 may involve the first device 110, the second device 120 and the third device 130 as illustrated in Fig. 1. It would be appreciated that although the process 600 has been described in the communication system 100 of Fig. 1, this process may be likewise applied to other communication scenarios. It would also be appreciated that although detecting CLI at the first device is discussed, a similar process can be applied for the third device or the fourth device.

As shown in Fig. 6, the second device 120 transmits 610 a configuration for SRS-RSRP measurement to the first device 110. The configuration at least indicates the number of antenna ports being used by the third device 130 for transmission of the SRS.

In some embodiments, the number of antenna ports may be 2 or 4.

Upon receiving the configuration, the first device 110 receives 620 the SRS from the third device 130 based on the configuration. The first device 110 determines 630 an estimation of CLI from the third device 130 based on the received SRS and the number of the antenna ports.

In some embodiments, the first device 110 may determine the estimation of CLI by performing a correlation operation on the received SRS. Consider an example. In this example, the first device 110 transforms the received SRS from time domain to frequency domain so as to obtain the received SRS in frequency domain. Then, the first device 110 performs resource element (RE) de-mapping on the received SRS in frequency domain to obtain a plurality of SRS corresponding to the antenna ports of the third device 130. Next, the first device 110 correlates the plurality of SRS with one or more SRS base sequences to obtain a correlation result. Then, the first device 110 transforms the correlation result from frequency domain to time domain. In turn, time or sample based windowing is used to detect the cyclic shift of the base sequences. In this example, some correlation peaks of SRS over samples in time domain may be obtained.

For example, in case where the number of antenna ports is 4, the four correlation peaks as shown in Fig. 2 may be obtained. Then, the first device 110 may determine a power level of at least one of the correlation peaks. For example, the first device 110 may determine a power level of one of the correlation peaks and determine a product of the power level and the number of antenna ports. Consequently, the first device 110 may determine the product as the estimation of CLI. For another example, the first device 110 may determine power levels of all of the correlation peaks and determine a sum of the power levels. Consequently, the first device 110 may determine the sum as the estimation of CLI.

It is to be appreciated that the above process where the first device 110 determines the estimation of CLI is described just for example, without suggesting any limitation as to the scope of the disclosure. Any appropriate process may be adapted for implementing implementations of the present disclosure.

In some embodiments, in addition to the number of antenna ports, the configuration may further indicate cyclic shifts for the SRS. In such embodiments, the first device 110 may determine the estimation of CLI based on the received SRS, the number of the antenna ports and the cyclic shifts.

In other embodiments, cyclic shifts for the sounding reference signals are preconfigured. In such embodiments, the first device 110 may determine the estimation based on the received sounding reference signals, the number of the antenna ports and the preconfigured cyclic shifts allocation.

In some embodiments, the configuration may further indicate a time domain resource on which the SRS are to be received. The time domain resource comprises a plurality of OFDM symbols. According to table 2, the number of symbols is configured to 1 for CLI SRS-RSRP measurement. To alleviate the impact due to timing error, the victim device may limit its measurement window to the largest time frame that allows for correct CLI measurement. For example, the measurement window width may be chosen to be plus/minus the minimum distance for cyclic shifts in the given configuration. The minimum distance can either be communicated from Network, or hardcoded in the spec. Thus, the issue that the victim device measures no correlation peaks or the correlation peaks from other ports due to the TE may be resolved.

In some embodiments, the configuration further indicates the minimum distance for cyclic shifts for SRS. In other embodiments, the minimum distance for cyclic shifts for SRS is preconfigured.

In some embodiments, the configuration may further indicate at least one of the following: subcarrier spacing for transmission of the SRS, a frequency domain resource on which the SRS is to be received, a transmission comb for the SRS and a sequence identity for the SRS.

With continued reference to Fig. 6, the first device 110 transmits 640 the estimation of the CLI to the second device 120.

With the process 600, the victim device is informed by the network of the number of antenna ports used by the aggressor device for SRS transmission. The victim device measures SRS-RSRP over all the antenna ports and obtains CLI measurement results accordingly. Thus, accurate CLI measurement results may be obtained and reported.

Reference is now made to Fig. 7, which shows a signaling chart illustrating a process 700 for detecting CLI according to some example embodiments of the present disclosure. For the purpose of discussion, the process 700 will be described with reference to Fig. 1. The process 700 may involve the first device 110, the second device 120 and the third device 130 as illustrated in Fig. 1. It would be appreciated that although the process 700 has been described in the communication system 100 of Fig. 1, this process may be likewise applied to other communication scenarios. It would also be appreciated that although detecting CLI at the first device is discussed, a similar process can be applied for the third device or the fourth device.

As shown in Fig. 7, the second device 120 transmits 710 a configuration for CLI SRS-RSRP measurement to the first device 110. In some embodiments, the configuration may indicate at least one of the following: subcarrier spacing for transmission of the SRS, a time domain resource on which the SRS is to be received, a frequency domain resource on which the SRS is to be received, a transmission comb for the SRS and a sequence identity for the SRS.

Upon receiving the configuration, the first device 110 receives 720 the SRS from the third device 130 based on the configuration.

The first device 110 determines 730 an estimation of CLI from the third device 130 based on the received SRS and a preconfigured threshold number of the antenna ports of the third device 130. The preconfigured threshold number of the antenna ports may be a maximum number of the antenna ports. The preconfigured threshold number of the antenna ports can either be communicated from Network, or hardcoded in the spec. For example, the preconfigured threshold number of the antenna ports may be 4.

In some embodiments, the first device 110 may determine the estimation of CLI by performing a correlation operation on the received SRS, as described with reference to Fig. 6.

The first device 110 transmits 740 the estimation of the CLI to the second device 120.

With the process 700, the victim device performs CLI SRS-RSRP measurement always assuming the preconfigured number of antenna ports, for example the maximum number of antenna ports 4. In this case, the victim device will detect all of the correlation peaks within the measurement window.

Reference is now made to Fig. 8, which shows a signaling chart illustrating a process 800 for detecting CLI according to some example embodiments of the present disclosure. For the purpose of discussion, the process 800 will be described with reference to Fig. 1. The process 800 may involve the first device 110, the second device 120, the third device 130 and the fourth device 140 as illustrated in Fig. 1. It would be appreciated that although the process 800 has been described in the communication system 100 of Fig. 1, this process may be likewise applied to other communication scenarios. It would also be appreciated that although detecting CLI at the first device is discussed, a similar process can be applied for the third device or the fourth device.

As shown in Fig. 8, the second device 120 transmits 810 a resource configuration for CLI SRS-RSRP measurement to the first device 110. The resource configuration at least indicates a resource on which the SRS is to be received.

Upon receiving the resource configuration, the first device 110 receives 820 the SRS from the third device 130 based on the resource configuration. Alternatively or in addition, the first device 110 may receive 830 the SRS from the fourth device 140 based on the configuration.

The first device 110 determines 840 an estimation of CLI from at least one of the third device 130 and the fourth device 140 based on the received SRS and predetermined configurations for the SRS. In some embodiments, the predetermined configurations for the SRS may indicate at least one of the following: combs offsets for the SRS from the third device 130 and the fourth device 140, a sequence identity for the SRS, cyclic shifts for the SRS.

In some embodiments, the first device 110 may determine the estimation of CLI by performing a correlation operation on the received SRS. Consider an example. In this example, the first device 110 transforms the received SRS from time domain to frequency domain so as to obtain the received SRS in frequency domain. Then, the first device 110 determines all possible SRS sequences based on the predetermined configurations for the SRS. For example, in case where the number of antenna ports of the third device 130 or the fourth device 140 is 2, the available comb offsets may be 0 and 1 and the available cyclic shifts may be any of 0, …, 7. For another example, in case where the number of antenna ports of the third device 130 or the fourth device 140 is 4, the comb offset may be 0, …, 3 and the cyclic shifts may be 0, …, 11. Thus, the first device 110 may determine all possible SRS sequences based on the available comb offsets and the available cyclic shifts.

In turn, the first device 110 may transform the received SRS in frequency domain with the all possible SRS sequences to obtain a correlation result. Then, the first device 110 may transform the correlation result from frequency domain to time domain so as to obtain a plurality of correlation peaks over samples in time domain. The plurality of correlation peaks may comprise one or more correlation peaks of the SRS from the third device 130, and/or one or more correlation peaks of the SRS from the fourth device 140.

In some embodiments, the first device 110 may determine the number of the correlation peaks of the received SRS and determine a power level of at least one of the correlation peaks as the estimation.

In other embodiments, the first device 110 may determine the number of the correlation peaks of the received SRS and determine a power level of at least one of the correlation peaks. In turn, the first device 110 may determine a product of the power level and the number of the correlation peaks as the estimation.

With continued reference to Fig. 8, the first device 110 transmits 850 the estimation of the CLI to the second device 120.

In some embodiments, the first device 110 may transmit the power level of at least one of the correlation peaks and the number of the correlation peaks to the second device 120. In this way, the second device 120 may determine a product of the power level and the number of the correlation peaks as the estimation. The second device 120 may further send the number of the correlation peaks to the network.

With the process 800, the victim device performs blind detection on the received SRS so as to determine the actual number of correlation peaks of SRS it detected within the measurement resource. Thus, accurate CLI measurement results may be obtained and reported.

Reference is now made to Fig. 9, which shows a signaling chart illustrating a process 900 for detecting CLI according to some example embodiments of the present disclosure. For the purpose of discussion, the process 900 will be described with reference to Fig. 1. The process 900 may involve the first device 110, the second device 120, the third device 130 and the fourth device 140 as illustrated in Fig. 1. It would be appreciated that although the process 900 has been described in the communication system 100 of Fig. 1, this process may be likewise applied to other communication scenarios. It would also be appreciated that although detecting CLI at the first device is discussed, a similar process can be applied for the third device or the fourth device.

As shown in Fig. 9, the third device 130 receives 910, from the fifth device 150, a configuration for SRS to be transmitted by the third device 130. The configuration at least indicates a first pattern for the SRS, a second pattern for the SRS, and a change from the first pattern to the second pattern. The third device 130 transmits 920 to the first device 110 the SRS based on the first and second patterns, and the change.

Upon receiving the SRS, the first device 110 determines 930 an estimation of CLI from the third device 130 based on the received SRS.

the first device 110 transmits 940 the estimation of CLI to the second device 120.

The second device 120 receives 950, from the fifth device 150, the configuration for SRS transmitted by the third device 130.

The second device 120 detects 960 the third device 130 based on the change and the estimation of CLI.

In some embodiments, the first pattern indicates at least one of the following: group hopping with a first initialization value for the first SRS, or sequence hopping with the first initialization value. The second pattern indicates at least one of the following: group hopping with a second initialization value for the second SRS, or sequence hopping with the second initialization value.

With the process 900, the network device of the aggressor device uses different SRS patterns for the aggressor device pre-emptively by using, for example, group hopping and/or sequence hopping with different initialization values. Thus, the network device of the victim device may identify the aggressor device with the different SRS patterns.

Reference is now made to Fig. 10, which shows a signaling chart illustrating a process 1000 for detecting CLI according to some example embodiments of the present disclosure. For the purpose of discussion, the process 1000 will be described with reference to Fig. 1. The process 1000 may involve the first device 110, the second device 120 and the fifth device 150 as illustrated in Fig. 1. It would be appreciated that although the process 1000 has been described in the communication system 100 of Fig. 1, this process may be likewise applied to other communication scenarios. It would also be appreciated that although detecting CLI at the first device is discussed, a similar process can be applied for the third device or the fourth device.

As shown in Fig. 10, the second device 120 receives 1010, from the fifth device 150, an indication of the number of antenna ports to be used by the third device 130 for transmission of SRS.

The second device 120 receives 1020, from the first device 110, an indication of a power level of one of the SRS from one of the antenna ports.

The second device 120 determines 1030 an estimation of CLI from the third device 130 to the first device 110 by increasing the power level based on the number of antenna ports used by the third device 130. In some embodiments, the second device 120 may determine a product of the power level and the number of antenna ports. In turn, the second device 120 may determine the product as the estimation of CLI.

With the process 1000, the network can anticipate the mis-configured CLI report and proactively upscale all received CLI measurement reports by a factor proportional to the actually configured number of antenna ports of the aggressor device.

Reference is now made to Fig. 11, which shows a signaling chart illustrating a process 1100 for detecting CLI according to some example embodiments of the present disclosure. For the purpose of discussion, the process 1100 will be described with reference to Fig. 1. The process 1100 may involve the first device 110, the second device 120, the third device 130 and the fifth device 150 as illustrated in Fig. 1. It would be appreciated that although the process 1100 has been described in the communication system 100 of Fig. 1, this process may be likewise applied to other communication scenarios. It would also be appreciated that although detecting CLI at the first device is discussed, a similar process can be applied for the third device or the fourth device.

As shown in Fig. 11, the third device 130 receives 1110 from the fifth device 150 a command indicating the third device 130 to increase transmission power levels of SRS.

In some embodiments, optionally, the first device 110 may transmit 1120 to the second device 120 an estimation of CLI from the third device 130. Upon receiving the estimation of CLI, the second device 120 may transmit 1130 to the fifth device 150 a request for increasing transmission power levels of SRS from the third device 130. Upon receiving the request, the fifth device 150 transmits the command 1110 to the third device 130.

The third device 130 increases 1140 the transmission power levels based on the number of antenna ports to be used by the third device 130 for transmission of the SRS. In some embodiments, the third device 130 may determine a product of the transmission power level and the number of antenna ports as the increased transmission power levels.

The third device 130 transmits 1150 the SRS with the increased transmission power levels to the first device 110 for estimation of CLI from the third device 130 to the first device 110.

With the process 1100, because the transmission power levels of SRS is increased, accurate CLI measurement results may be obtained and reported.

Fig. 12 shows a flowchart of an example method 1200 implemented at a device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1200 will be described from the perspective of the first device 110 with reference to Fig. 1. It would be appreciated that the method 1200 may also be implemented at the third device 130 or the fourth device 140 in Fig. 1.

At block 1210, the first device 110 receives a configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals.

At block 1220, the first device 110 receives the sounding reference signals from the third device based on the configuration.

At block 1230, the first device 110 determines an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports.

At block 1240, the first device 110 transmits the estimation of the cross link interference to the second device.

In some embodiments, the configuration further indicates cyclic shift for the sounding reference signals; and determining the estimation of the cross link interference comprises: determining the estimation based on the received sounding reference signals, the number of the antenna ports and the cyclic shifts.

In some embodiments, the configuration further indicates a time domain resource on which the sounding reference signals are to be received, the time domain resource comprises a plurality of Orthogonal Frequency Division Multiplexing symbols.

Fig. 13 shows a flowchart of an example method 1300 implemented at a device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1300 will be described from the perspective of the first device 110 with reference to Fig. 1. It would be appreciated that the method 1300 may also be implemented at the third device 130 or the fourth device 140 in Fig. 1.

At block 1310, the first device 110 receives a measurement configuration for sounding reference signals from a second device.

At block 1320, the first device 110 receives the sounding reference signals from a third device based on the configuration.

At block 1330, the first device 110 determines an estimation of cross link interference from the third device based on the received sounding reference signals and a preconfigured threshold number of the antenna ports.

At block 1340, the first device 110 transmits the estimation of the cross link interference to the second device.

Fig. 14 shows a flowchart of an example method 1400 implemented at a device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1400 will be described from the perspective of the first device 110 with reference to Fig. 1. It would be appreciated that the method 1400 may also be implemented at the third device 130 or the fourth device 140 in Fig. 1.

At block 1410, the first device 110 receives a resource configuration for sounding reference signals from a second device, the resource configuration at least indicating a resource on which the sounding reference signals are to be received.

At block 1420, the first device 110 receives sounding reference signals from at least one of a third device and a fourth device based on the resource configuration.

At block 1430, the first device 110 determines an estimation of cross link interference from the at least one of the third and fourth devices based on the received sounding reference signals and predetermined configurations for the sounding reference signals.

At block 1440, the first device 110 transmits the estimation of the cross link interference to the second device.

In some embodiments, determining the estimation of the cross link interference comprises: determining the number of correlation peaks of the received sounding reference signals; and determining a power level of at least one of the correlation peaks as the estimation.

In some embodiments, transmitting the estimation comprises: transmitting the power level and the number of the correlation peaks to the second device.

In some embodiments, determining the estimation of the cross link interference comprises: determining the number of correlation peaks of the received sounding reference signals; determining a power level of at least one of the correlation peaks; and determining a product of the power level and the number of the correlation peaks as the estimation.

Fig. 15 shows a flowchart of an example method 1500 implemented at a device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1500 will be described from the perspective of the second device 120 with reference to Fig. 1. It would be appreciated that the method 1500 may also be implemented at the fifth device 150 in Fig. 1.

At block 1510, the second device 120 transmits a configuration for sounding reference signals to a first device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals.

At block 1520, the second device 120 receives, from the first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals and the number of the antenna ports.

In some embodiments, the configuration further indicates cyclic shifts for the sounding reference signals; and the estimation is determined based on the sounding reference signals, the number of the antenna ports and the cyclic shifts.

Fig. 16 shows a flowchart of an example method 1600 implemented at a device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1600 will be described from the perspective of the second device 120 with reference to Fig. 1. It would be appreciated that the method 1600 may also be implemented at the fifth device 150 in Fig. 1.

At block 1610, the second device 120 receives, from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern.

At block 1620, the second device 120 receives, from a first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals.

At block 1630, the second device 120 detects the third device based on the change and the estimation of cross link interference.

In some embodiments, the first pattern indicates at least one of the following: group hopping with a first initialization value for the first sounding reference signal, or sequence hopping with the first initialization value; and the second pattern indicates at least one of the following: group hopping with a second initialization value for the second sounding reference signal, or sequence hopping with the second initialization value.

Fig. 17 shows a flowchart of an example method 1700 implemented at a device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1700 will be described from the perspective of the second device 120 with reference to Fig. 1. It would be appreciated that the method 1700 may also be implemented at the fifth device 150 in Fig. 1.

At block 1710, the second device 120 receives, from a fifth device, an indication of the number of antenna ports to be used by a third device for transmission of sounding reference signals.

At block 1720, the second device 120 receives, from the first device, an indication of a power level of one of the sounding reference signals from one of the antenna ports.

At block 1730, the second device 120 determines an estimation of cross link interference from the third device to the first device by increasing the power level based on the number of antenna ports.

Fig. 18 shows a flowchart of an example method 1800 implemented at a device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1800 will be described from the perspective of the third device 130 with reference to Fig. 1. It would be appreciated that the method 1800 may also be implemented at the fourth device 140 in Fig. 1.

At block 1810, the third device 130 receives from a fifth device a command indicating the third device to increase transmission power levels of sounding reference signals.

At block 1820, the third device 130 increases the transmission power levels based on the number of antenna ports to be used by the third device for transmission of the sounding reference signals.

At block 1830, the third device 130 transmits the sounding reference signals with the increased transmission power levels to a first device for estimation of cross link interference from the third device to the first device.

Fig. 19 shows a flowchart of an example method 1900 implemented at a device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 1900 will be described from the perspective of the third device 130 with reference to Fig. 1. It would be appreciated that the method 1900 may also be implemented at the fourth device 140 in Fig. 1.

At block 1910, the third device 130 receives, from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern.

At block 1920, the third device 130 transmits to a second device the sounding reference signals based on the first and second patterns, and the change.

It shall be appreciated that descriptions of features with reference to Figs. 1 to 11 also apply to the methods 1200 to 1900, and have the same effects. Thus, the details of the features are omitted.

In some example embodiments, an apparatus capable of performing any of the method 1200 (for example, the first device 110) may comprise means for performing the respective steps of the method 1200. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for receiving, at a first device, a configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals; means for receiving the sounding reference signals from the third device based on the configuration; means for determining an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports; and means for transmitting the estimation of the cross link interference to the second device.

In some embodiments, the configuration further indicates cyclic shifts for the sounding reference signals; and determining the estimation of the cross link interference comprises: determining the estimation based on the received sounding reference signals, the number of the antenna ports and the cyclic shifts.

In some example embodiments, an apparatus capable of performing any of the method 1300 (for example, the first device 110) may comprise means for performing the respective steps of the method 1300. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for receiving, at a first device, a configuration for sounding reference signals from a second device; means for receiving the sounding reference signals from a third device based on the configuration; means for determining an estimation of cross link interference from the third device based on the received sounding reference signals and a preconfigured threshold number of the antenna ports; and means for transmitting the estimation of the cross link interference to the second device.

In some example embodiments, an apparatus capable of performing any of the method 1400 (for example, the first device 110) may comprise means for performing the respective steps of the method 1400. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for receiving, at a first device, a resource configuration for sounding reference signals from a second device, the resource configuration at least indicating a resource on which the sounding reference signals are to be received; means for receiving sounding reference signals from at least one of a third device and a fourth device based on the resource configuration; means for determining an estimation of cross link interference from the at least one of the third and fourth devices based on the received sounding reference signals and predetermined configurations for the sounding reference signals; and means for transmitting the estimation of the cross link interference to the second device.

In some embodiments, means for determining the estimation of the cross link interference comprises: means for determining the number of correlation peaks of the received sounding reference signals; and determining a power level of at least one of the correlation peaks as the estimation.

In some embodiments, means for transmitting the estimation comprises: transmitting the power level and the number of the correlation peaks to the second device.

In some embodiments, means for determining the estimation of the cross link interference comprises: means for determining the number of correlation peaks of the received sounding reference signals; determining a power level of at least one of the correlation peaks; and determining a product of the power level and the number of the correlation peaks as the estimation.

In some example embodiments, an apparatus capable of performing any of the method 1500 (for example, the second device 120) may comprise means for performing the respective steps of the method 1500. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for transmitting, at a second device, a configuration for sounding reference signals to a first device, the configuration at least indicating the number of antenna ports to be used by a third device for transmission of the sounding reference signals; and means for receiving, from the first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals and the number of the antenna ports.

In some example embodiments, an apparatus capable of performing any of the method 1600 (for example, the second device 120) may comprise means for performing the respective steps of the method 1600. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for receiving, at a second device and from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern; means for receiving, from a first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals; and means for detecting the third device based on the change and the estimation of cross link interference.

In some example embodiments, an apparatus capable of performing any of the method 1700 (for example, the second device 120) may comprise means for performing the respective steps of the method 1700. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for receiving, at a second device and from a fifth device, an indication of the number of antenna ports to be used by a third device for transmission of sounding reference signals; means for receiving, from the first device, an indication of a power level of one of the sounding reference signals from one of the antenna ports; and means for determining an estimation of cross link interference from the third device to the first device by increasing the power level based on the number of antenna ports.

In some example embodiments, an apparatus capable of performing any of the method 1800 (for example, the third device 130) may comprise means for performing the respective steps of the method 1800. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for receiving, at a third device and from a fifth device a command indicating the third device to increase transmission power levels of sounding reference signals; means for increasing the transmission power levels based on the number of antenna ports to be used by the third device for transmission of the sounding reference signals; and means for transmitting the sounding reference signals with the increased transmission power levels to a first device for estimation of cross link interference from the third device to the first device.

In some example embodiments, an apparatus capable of performing any of the method 1900 (for example, the third device 130) may comprise means for performing the respective steps of the method 1900. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for receiving, at a third device and from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern; means for transmitting the sounding reference signals based on the first and second patterns, and the change.

Fig. 20 is a simplified block diagram of a device 2000 that is suitable for implementing embodiments of the present disclosure. The device 2000 may be provided to implement the communication device, for example the first device 110, the second device 120, the third device 130, the fourth device 140 or the fifth device 150 as shown in Fig. 1. As shown, the device 2000 includes one or more processors 2010, one or more memories 2020 coupled to the processor 2010, and one or more communication modules 2040 coupled to the processor 2010.

The communication module 2040 is for bidirectional communications. The communication module 2040 has at least one antenna to facilitate communication. The communication interface may represent any interface that is necessary for communication with other network elements.

The processor 2010 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 2000 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

The memory 2020 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 2024, an electrically programmable read only memory (EPROM) , a flash memory, a hard disk, a compact disc (CD) , a digital video disk (DVD) , and other magnetic storage and/or optical storage. Examples of the volatile memories include, but are not limited to, a random access memory (RAM) 2022 and other volatile memories that will not last in the power-down duration.

A computer program 2030 includes computer executable instructions that are executed by the associated processor 2010. The program 2030 may be stored in the ROM 2024. The processor 2010 may perform any suitable actions and processing by loading the program 2030 into the RAM 2022.

The embodiments of the present disclosure may be implemented by means of the program 2030 so that the device 2000 may perform any process of the disclosure as discussed with reference to Figs. 2 to 19. The embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

In some example embodiments, the program 2030 may be tangibly contained in a computer readable medium which may be included in the device 2000 (such as in the memory 2020) or other storage devices that are accessible by the device 2000. The device 2000 may load the program 2030 from the computer readable medium to the RAM 2022 for execution. The computer readable medium may include any types of tangible non-volatile storage, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. Fig. 21 shows an example of the computer readable medium 2100 in form of CD or DVD. The computer readable medium has the program 2030 stored thereon.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the methods 1200 to 1900 as described above with reference to Figs. 12 to 18. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present disclosure, the computer program codes or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in languages specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A first device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the first device to:

receive a measurement configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports used by a third device for transmission of the sounding reference signals;

receive the sounding reference signals from the third device based on the configuration;

determine an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports; and

transmit the estimation of the cross link interference to the second device.
The first device of Claim 1, wherein:

the configuration indicates cyclic shifts for the sounding reference signals; and

the first device is caused to determine the estimation of the cross link interference by:

determining the estimation based on the received sounding reference signals, the number of the antenna ports and the cyclic shifts.
The first device of Claim 1, wherein the number of antenna ports and/or cyclic shifts for the sounding reference signals are preconfigured; and

the first device is caused to determine the estimation of the cross link interference by:

determining the estimation based on the received sounding reference signals, the number of the antenna ports and the preconfigured cyclic shifts.
The first device of Claim 1, wherein:

the configuration further indicates a time domain resource on which the sounding reference signals are to be received, the time domain resource comprises a plurality of Orthogonal Frequency Division Multiplexing symbols.
The first device of Claim 4, wherein the configuration further indicates a minimum distance for cyclic shifts for the sounding reference signals.
The first device of Claim 4, wherein a minimum distance for cyclic shifts for the sounding reference signals is preconfigured.
The first device of Claim 1, wherein the first device is a victim terminal device, the second device is a network device serving the first device, and the third device is an aggressor terminal device.
A first device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the first device to:

receive a measurement configuration for sounding reference signals from a second device;

receive the sounding reference signals from a third device based on the configuration;

determine an estimation of cross link interference from the third device based on the received sounding reference signals and a preconfigured threshold number of the antenna ports; and

transmit the estimation of the cross link interference to the second device.
A first device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the first device to:

receive a resource configuration for sounding reference signals from a second device, the resource configuration at least indicating a resource on which the sounding reference signals are to be received,

receive sounding reference signals from at least one of a third device and a fourth device based on the resource configuration;

determine an estimation of cross link interference from the at least one of the third and fourth devices based on the received sounding reference signals and predetermined configurations for the sounding reference signals; and

transmit the estimation of the cross link interference to the second device. Adding dependent claims explaining “predetermined configurations” , not only cyclic shifts, but also all samples.
The first device of Claim 9, wherein the predetermined configurations indicate at least one of the following:

at least one transmission comb for the sounding reference signals, or

at least one cyclic shift for the sounding reference signals.
The first device of Claim 9, wherein the first device is caused to determine the estimation of the cross link interference by:

determining the number of correlation peaks of the received sounding reference signals; and

determining a power level of at least one of the correlation peaks as the estimation.
The first device of Claim 11, wherein the first device is caused to transmit the estimation by:

transmitting the power level and the number of the correlation peaks to the second device.
The first device of Claim 9, wherein the first device is caused to determine the estimation of the cross link interference by:

determining the number of correlation peaks of the received sounding reference signals;

determining a power level of at least one of the correlation peaks; and

determining a product of the power level and the number of the correlation peaks as the estimation.
A second device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the second device to:

transmit a measurement configuration for sounding reference signals to a first device, the configuration at least indicating the number of antenna ports used by a third device for transmission of the sounding reference signals; and

receive, from the first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals and the number of the antenna ports.
The second device of Claim 14, wherein:

the configuration further indicates cyclic shifts for the sounding reference signals; and

the estimation is determined based on the sounding reference signals, the number of the antenna ports and the cyclic shifts.
The second device of Claim 14, wherein:

the configuration further indicates a time domain resource on which the sounding reference signals are to be received, the time domain resource comprises a plurality of Orthogonal Frequency Division Multiplexing symbols.
A second device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the second device to:

receive, from a fifth device, a configuration for sounding reference signals to be transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern;

receive, from a first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals; and

detect the third device based on the change and the estimation of cross link interference.
The second device of Claim 17, wherein:

the first pattern indicates at least one of the following:

group hopping with a first initialization value for the first sounding reference signal, or

sequence hopping with the first initialization value; and

the second pattern indicates at least one of the following:

group hopping with a second initialization value for the second sounding reference signal, or

sequence hopping with the second initialization value.
A second device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the second device to:

receive, from a fifth device, an indication of the number of antenna ports used by a third device for transmission of sounding reference signals;

receive, from the first device, an indication of a power level of one of the sounding reference signals from one of the antenna ports; and

determine an estimation of cross link interference from the third device to the first device by increasing the power level based on the number of antenna ports.
A third device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the third device to:

receive from a fifth device a command indicating the third device to increase transmission power levels of sounding reference signals;

increase the transmission power levels based on the number of antenna ports used by the third device for transmission of the sounding reference signals; and

transmit the sounding reference signals with the increased transmission power levels to a first device for estimation of cross link interference from the third device to the first device.
A third device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the third device to:

receive, from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern;

transmit the sounding reference signals based on the first and second patterns, and the change.
A method, comprising:

receiving, at a first device, a measurement configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports used by a third device for transmission of the sounding reference signals;

receiving the sounding reference signals from the third device based on the configuration;

determining an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports; and

transmitting the estimation of the cross link interference to the second device.
A method, comprising:

receiving, at a first device, a measurement configuration for sounding reference signals from a second device;

receiving the sounding reference signals from a third device based on the configuration;

determining an estimation of cross link interference from the third device based on the received sounding reference signals and a preconfigured threshold number of the antenna ports; and

transmitting the estimation of the cross link interference to the second device.
A method, comprising:

receiving, at a first device, a resource configuration for sounding reference signals from a second device, the resource configuration at least indicating a resource on which the sounding reference signals are to be received,

receiving sounding reference signals from at least one of a third device and a fourth device based on the resource configuration;

determining an estimation of cross link interference from the at least one of the third and fourth devices based on the received sounding reference signals and predetermined configurations for the sounding reference signals; and

transmitting the estimation of the cross link interference to the second device.
A method, comprising:

transmitting, at a second device, a measurement configuration for sounding reference signals to a first device, the configuration at least indicating the number of antenna ports used by a third device for transmission of the sounding reference signals; and

receiving, from the first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals and the number of the antenna ports.
A method, comprising:

receiving, at a second device and from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern;

receiving, from a first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals; and

detecting the third device based on the change and the estimation of cross link interference.
A method, comprising:

receiving, at a second device and from a fifth device, an indication of the number of antenna ports used by a third device for transmission of sounding reference signals;

receiving, from the first device, an indication of a power level of one of the sounding reference signals from one of the antenna ports; and

determining an estimation of cross link interference from the third device to the first device by increasing the power level based on the number of antenna ports.
A method, comprising:

receiving, at a third device and from a fifth device a command indicating the third device to increase transmission power levels of sounding reference signals;

increasing the transmission power levels based on the number of antenna ports used by the third device for transmission of the sounding reference signals; and

transmitting the sounding reference signals with the increased transmission power levels to a first device for estimation of cross link interference from the third device to the first device.
A method, comprising:

receiving, at a third device and from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern;

transmitting the sounding reference signals based on the first and second patterns, and the change.
An apparatus, comprising:

means for receiving, at a first device, a measurement configuration for sounding reference signals from a second device, the configuration at least indicating the number of antenna ports used by a third device for transmission of the sounding reference signals;

means for receiving the sounding reference signals from the third device based on the configuration;

means for determining an estimation of cross link interference from the third device based on the received sounding reference signals and the number of the antenna ports; and

means for transmitting the estimation of the cross link interference to the second device.
An apparatus, comprising:

means for receiving, at a first device, a measurement configuration for sounding reference signals from a second device;

means for receiving the sounding reference signals from a third device based on the configuration;

means for determining an estimation of cross link interference from the third device based on the received sounding reference signals and a preconfigured threshold number of the antenna ports; and

means for transmitting the estimation of the cross link interference to the second device.
An apparatus, comprising:

means for receiving, at a first device, a resource configuration for sounding reference signals from a second device, the resource configuration at least indicating a resource on which the sounding reference signals are to be received;

means for receiving sounding reference signals from at least one of a third device and a fourth device based on the resource configuration;

means for determining an estimation of cross link interference from the at least one of the third and fourth devices based on the received sounding reference signals and predetermined configurations for the sounding reference signals; and

means for transmitting the estimation of the cross link interference to the second device.
An apparatus, comprising:

means for transmitting, at a second device, a measurement configuration for sounding reference signals to a first device, the configuration at least indicating the number of antenna ports used by a third device for transmission of the sounding reference signals; and

means for receiving, from the first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals and the number of the antenna ports.
An apparatus, comprising:

means for receiving, at a second device and from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern;

means for receiving, from a first device, an estimation of cross link interference from the third device to the first device, the estimation being determined based on the sounding reference signals; and

means for detecting the third device based on the change and the estimation of cross link interference.
An apparatus, comprising:

means for receiving, at a second device and from a fifth device, an indication of the number of antenna ports used by a third device for transmission of sounding reference signals;

means for receiving, from the first device, an indication of a power level of one of the sounding reference signals from one of the antenna ports; and

means for determining an estimation of cross link interference from the third device to the first device by increasing the power level based on the number of antenna ports.
An apparatus, comprising:

means for receiving, at a third device and from a fifth device a command indicating the third device to increase transmission power levels of sounding reference signals;

means for increasing the transmission power levels based on the number of antenna ports used by the third device for transmission of the sounding reference signals; and

means for transmitting the sounding reference signals with the increased transmission power levels to a first device for estimation of cross link interference from the third device to the first device.
An apparatus, comprising:

means for receiving, at a third device and from a fifth device, a configuration for sounding reference signals transmitted by a third device, the configuration at least indicating a first pattern for the sounding reference signals, a second pattern for the sounding reference signals, and a change from the first pattern to the second pattern;

means for transmitting the sounding reference signals based on the first and second patterns, and the change.
A computer readable medium comprising a computer program for causing an apparatus to perform at least the method of any of Claims 22 to 29.