WO2022216545A1

WO2022216545A1 - Methods of defining frequency domain starting position for srs partial frequency sounding

Info

Publication number: WO2022216545A1
Application number: PCT/US2022/023076
Authority: WO
Inventors: Nadisanka Rupasinghe; Yuki Matsumura
Original assignee: Ntt Docomo, Inc.; Docomo Innovations, Inc.
Priority date: 2021-04-07
Filing date: 2022-04-01
Publication date: 2022-10-13
Also published as: JP2024515047A; EP4320793A1; CN117321950A

Abstract

A wireless communication method is disclosed that includes receiving, via downlink control information (DCI) or higher layer signaling, configuration information including a frequency sounding with Sounding Reference Signal (SRS) configuration. The method further includes configuring partial frequency sounding with SRS transmission based on the configuration information and determining a frequency domain starting position of the SRS for partial frequency sounding. In other aspects, a terminal and a system are also disclosed.

Description

METHODS OF DEFINING FREQUENCY DOMAIN STARTING POSITION FOR SRS PARTIAL FREQUENCY SOUNDING

BACKGROUND

Technical Field

[0001] One or more embodiments disclosed herein relate to mechanism(s) to define a starting position in frequency domain for a Sounding Reference Signal (SRS) configured with partial band sounding.

Description of Related Art

[0002] A SRS is a reference signal for a base station to determine a channel quality of an uplink channel for each subsection of a frequency region. In 5G new radio (NR) technologies, new requirements are being identified for further enhancing SRS transmission. New items in Rel. 17 relate to, for example, NR. Multiple-Input-Multiple-Output (MIMO).

[0003] In the new studies being conducted, enhancement of the SRS is targeted for both Frequency Range (FR) 1 and FR2. In particular, study is under way to identify and specify enhancements on aperiodic SRS triggering to facilitate more flexible triggering and/or Downlink Control Information (DCI) overhead/ usage reduction.

[0004] Additionally, study is under way to specify SRS switching for up to 8 antennas (e.g., xTyR, x = {1, 2, 4} and y = {6, 8}).

[0005] Further, studies are evaluating and, if needed, specifying the following mechanism(s) to enhance SRS capacity and/or coverage including SRS time bundling, increased SRS repetition, and/or partial sounding across frequency. In this work, the mechanisms of how partial sounding across frequency can be introduced to enhance SRS coverage and capacity are being discussed.

[0006] More specifically, in the meeting of 3GPP RANI #104-e [2], an agreement has been reached regarding partial frequency sounding of SRS. In a condition that SRS is transmitted ⁱⁿ contiguous resource blocks (RB) in one orthogonal frequency-division

multiplexing (OFDM) symbol, the value of P_F is at least one from {2, [3], 4, 8}. The

indicates a number of RBs configured by B_SRS and C_SRS. In the transmission process, no new sequence including length is introduced. Further topics including non- integer values for P_F, applicability for frequency hopping and non-frequency hopping in transmitting the SRS, and detailed signaling mechanism to determine P_F and locations of RBs may be studied in the future. In the present application, methods of defining frequency domain starting position for SRS partial frequency sounding are considered.

Citation List

Non-Patent References

[0007] [Non-Patent Reference 1] 3GPPRP 193133, “New WID: Further enhancements on MIMO for NR,” Dec., 2019.

[0008] [Non-Patent Reference 2] 3GPP RAN1 #104-e, “Chairman’s Notes,” Feb. 2021.

[0009] [Non-Patent Reference 3] 3GPP TS 38.211, “NR; Physical channels and modulation (Release 16).”

SUMMARY

[0010] One or more embodiments of the present invention provide a wireless communication method including receiving, via downlink control information (DCI) or higher layer signaling, configuration information including a frequency sounding with Sounding Reference Signal (SRS) configuration, configuring partial frequency sounding based on the configuration information, and determining a frequency domain starting position for SRS partial frequency sounding.

[0011] In one aspect, the configuration information is signaled by Radio Resource Control (RRC) signaling.

[0012] In one aspect, the configuration information is dynamically updated/configured by one of Downlink Control Information (DCI) and a Medium Access Control Control Element (MAC-CE).

[0013] Other embodiments and advantages of the present invention will be recognized from the description and figures. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a diagram showing a schematic configuration of a wireless communications system according to embodiments.

[0015] FIG. 2 is a diagram showing a schematic configuration of a base station according to embodiments.

[0016] FIG. 3 is a schematic configuration of a UE according to embodiments.

[0017] FIG. 4 is a table of SRS sounding bandwddths.

[0018] FIG. 5 shows an example of SRS bandwidth configuration.

[0019] FIG 6 shows an example of a frequency domain starting position.

[0020] FIG. 7 shows an example of partial frequency sounding with SRS.

[0021] FIG 8 shows an example of frequency domain starting position for partial frequency sounding.

[0022] FIG 9 is a portion of FIG. 8.

[0023] FIG. 10 shows an example of frequency domain starting position for partial frequency sounding.

[0024] FIG. 11 shows an example of a configuration of a parameter.

[0025] FIG. 12 shows an example of a configuration of a parameter.

[0026] FIG. 13 shows an example of a configuration of a parameter.

[0027] FIG. 14 shows an example of a configuration of a parameter.

[0028] FIG. 15 shows an example of frequency domain starting position for partial frequency sounding.

DETAILED DESCRIPTION

[0029] Embodiments of the present invention will be described in detail below with reference to the drawings. Like elements in the various figures are denoted by like reference numerals for consistency.

[0030] In the following description of embodiments of the invention, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid obscuring the invention. [0031] FIG. 1 describes a wireless communications system 1 according to one or more embodiments of the present invention. The wireless communication system 1 includes a user equipment (UE) 10, a base station (BS) 20, and a core network 30. The wireless communication system 1 may be a NR system. The wireless communication system 1 is not limited to the specific configurations described herein and may be any type of wireless communication system such as an LTE/LTE- Advanced (LTE-A) system.

[0032] The BS 20 may communicate uplink (UL) and downlink (DL) signals with the UE 10 in a cell of the BS 20. The DL and UL signals may include control information and user data. The BS 20 may communicate DL and UL signals with the core network 30 through backhaul links 31. The BS 20 may be gNodeB (gNB). The BS 20 may be referred to as a network (NW) 20.

[0033] The BS 20 includes antennas, a communication interface to communicate with an adjacent BS 20 (for example, X2 interface), a communication interface to communicate with the core network 30 (for example, S1 interface), and a CPU (Central Processing Unit) such as a processor or a circuit to process transmitted and received signals with the UE 10. Operations of the BS 20 may be implemented by the processor processing or executing data and programs stored in a memory. However, the BS 20 is not limited to the hardware configuration set forth above and may be realized by other appropriate hardware configurations as understood by those of ordinary skill in the art. Numerous BSs 20 may be disposed so as to cover a broader service area of the wireless communication system 1.

[0034] The UE 10 may communicate DL and UL signals that include control information and user data with the BS 20 using Multi Input Multi Output (MIMO) technology. The UE 10 may be a mobile station, a smartphone, a cellular phone, a tablet, a mobile router, or information processing apparatus having a radio communication function such as a wearable device. The wireless communication system 1 may include one or more UEs 10.

[0035] The UE 10 includes a CPU such as a processor, a RAM (Random Access Memory), a flash memory, and a radio communication device to transmit/receive radio signals to/from the BS 20 and the UE 10. For example, operations of the UE 10 described below may be implemented by the CPU processing or executing data and programs stored in a memory. However, the UE 10 is not limited to the hardware configuration set forth above and may be configured with, e.g., a circuit to achieve the processing described below. [0036] As shown in FIG. 1, the BS 20 may transmit a CSI-Reference Signal (CSI-RS) to the UE 10. In response, the UE 10 may transmit a CSI report to the BS 20. Similarly, the UE 10 may transmit SRS to the BS 20.

[0037] (Configuration of BS)

[0038] The BS 20 according to embodiments of the present invention will be described below with reference to FIG. 2. FIG. 2 is a diagram illustrating a schematic configuration of the BS 20 according to embodiments of the present invention. The BS 20 may include a plurality of antennas (antenna element group) 201, amplifier 202, transceiver (transmitter/receiver) 203, a baseband signal processor 204, a call processor 205 and a transmission path interface 206.

[0039] User data that is transmitted on the DL from the BS 20 to the UE 20 is input from the core network, through the transmission path interface 206, into the baseband signal processor 204.

[0040] In the baseband signal processor 204, signals are subjected to Packet Data Convergence Protocol (PDCP) layer processing. Radio Link Control (RLC) layer transmission processing such as division and coupling of user data and RLC retransmission control transmission processing, Medium Access Control (MAC) retransmission control, including, for example, HARQ transmission processing, scheduling, transport format selection, channel coding, inverse fast Fourier transform (IFFT) processing, and precoding processing. Then, the resultant signals are transferred to each transceiver 203. As for signals of the DL control channel, transmission processing is performed, including channel coding and inverse fast Fourier transform, and the resultant signals are transmitted to each transceiver 203.

[0041] The baseband signal processor 204 notifies each UE 10 of control information (system information) for communication in the cell by higher layer signaling (e.g., Radio Resource Control (RRC) signaling and broadcast channel). Information for communication in the cell includes, for example, UL or DL system bandwidth.

[0042] In each transceiver 203, baseband signals that are precoded per antenna and output from the baseband signal processor 204 are subjected to frequency conversion processing into a radio frequency band. The amplifier 202 amplifies the radio frequency signals having been subjected to frequency conversion, and the resultant signals are transmitted from the antennas 201. [0043] As for data to be transmitted on the UL from the UE 10 to the BS 20, radio frequency signals are received in each antennas 201, amplified in the amplifier 202, subjected to frequency conversion and converted into baseband signals in the transceiver 203, and are input to the baseband signal processor 204.

[0044] The baseband signal processor 204 performs FFT processing, IDFT processing, error correction decoding, MAC retransmission control reception processing, and RLC layer and PDCP layer reception processing on the user data included in the received baseband signals. Then, the resultant signals are transferred to the core network through the transmission path interface 206. The call processor 205 performs call processing such as setting up and releasing a communication channel, manages the state of the BS 20, and manages the radio resources.

[0045] (Configuration of UE)

[0046] The UE 10 according to embodiments of the present invention will be described below with reference to FIG. 3. FIG. 3 is a schematic configuration of the UE 10 according to embodiments of the present invention. The UE 10 has a plurality of UE antenna S101, amplifiers 102, the circuit 103 comprising transceiver (transmitter/receiver) 1031, the controller 104, and an application 105.

[0047] As for DL, radio frequency signals received in the UE antenna S101 are amplified in the respective amplifiers 102, and subjected to frequency conversion into baseband signals in the transceiver 1031. These baseband signals are subjected to reception processing such as FFT processing, error correction decoding and retransmission control and so on, in the controller 104. The DL user data is transferred to the application 105. The application 105 performs processing related to higher layers above the physical layer and the MAC layer. In the downlink data, broadcast information is also transferred to the application 105.

[0048] On the other hand, UL user data is input from the application 105 to the controller 104. In the controller 104, retransmission control (Hybrid ARQ) transmission processing, channel coding, precoding, DFT processing, IFFT processing and so on are performed, and the resultant signals are transferred to each transceiver 1031. In the transceiver 1031, the baseband signals output from the controller 104 are converted into a radio frequency band. After that, the frequency- converted radio frequency signals are amplified in the amplifier 102, and then, transmitted from the antenna 101.

[0049] As discussed above, consideration is given with regard to SRS partial frequency sounding. One or more embodiments described herein may provide methods for defining frequency domain starting position for SRS partial frequency sounding. [0050] In one or more embodiments, SRS bandwidth may be configured based on the values shown in FIG. 4. Specifically, FIG. 4 focuses on an example with an index value C_SRS 13. In this example, there may be a single bandwidth (BW) region for SRS with a length of 48 RBs. Alternatively, there may be two BW regions for SRS with a length of 24 RBs each. Alternatively, there may be four BW regions for SRS with a length of 12 RBs each. Yet alternatively, there may be twelve regions for SRS with a length of 4 RBs each. In other words, with different SRS bandwidths, the available bandwidths may be divided into a different number of parts. Such features may be useful in SRS frequency hopping when the SRS transmission is split into a series of narrowband transmissions that cover the whole bandwidth region of interest. Values for C_SRS and B_SRS may be configured by higher-layer signaling.

[0051] FIG. 5 describes one or more embodiments that illustrate the SRS bandwidth configuration based on the example of FIG. 4. Index C_SRS configures a set of SRS bandwidths as described above, while B_SRS selects one bandwidth out of the configured set and divides the available bandwidths into a different number of parts. Specifically, as B_SRS increases, the size of the partitions decreases. In other words, as the number of sounding bands increases, the number of frequency partitions increases as well.

[0052] FIG. 6 shows an example of a frequency domain starting position. The frequency domain starting position of the SRS may be determined by a cell-specific SRS bandwidth configuration that is configured by higher layer signaling. Specifically, as described in FIG. 6, the starting position

may be determined based on the equation (1):

[0053] To explain, is a value calculated based on is a

frequency domain shift value that adjusts the SRS allocation with respect to a reference grid point and is transmitted via higher layer signaling. indicates a number of sub-carriers in an RB.

is a transmission comb parameter offset.

[0054] In addition, is a length of the sounding reference signal sequence. More

specifically, the is determined based on The values of m

_{SRS, b}

and N_b are given in the selected row of FIG. 4. As explained above, the indicates the number

of sub-carriers in an RB. The K_TC is the transmission comb parameter specified by higher layer signaling. The B_SRS is selected from {0, 1, 2, 3} as given by a field contained in the higher-layer parameter.

[0055] As mentioned above, the values of N_b are given in the selected row of FIG. 4. To explain, when a frequency hopping parameter b_hop is greater than or equal to the value of B_SRS, frequency hopping may be disabled and the frequency position index n_b remains as a constant value for all OFDM symbols of the SRS resource as defined by the above equation. The n_RRC in the above equation indicates a frequency domain position.

[0056] Therefore, the frequency domain starting position may be defined based on

the above equations and parameters.

[0057] In one or more embodiments with reference to an example shown in FIG. 7, partial frequency sounding with SRS may be performed. In particular, using higher-layer signaling or DCI, the UE is configured to consider partial bandwidth SRS transmission. One or more potential advantages of partial frequency sounding include the following possibilities.

[0058] Compared to full-band sounding, partial-band sounding (or partial-frequency sounding) provides a way to boost the per-subcarrier power since the available transmit power is allocated over a smaller bandwidth partition. Further, it enhances the SRS capacity as it gives an opportunity for the network to multiplex more UE ports on the rest of frequency resource.

[0059] To illustrate, in the example shown in FIG. 7 a legacy SRS transmission with 24 RBs is configured with partial frequency sounding. After partial SRS configuration, the SRS transmission may be accomplished over only half of the available bandwidth within each hop.

[0060] One or more potential disadvantages may be that since the entire band is not sounded from SRS transmission within a slot, frequency selective scheduling over the whole DL transmission bandwidth may not be feasible. Further, due to partial frequency sounding, the NW may not be able to extract the interference structure of the channel.

[0061] FIG. 8 shows an example of frequency domain starting position for partial frequency sounding according to one or more embodiments. As shown in FIG. 8, only part of the configured SRS sounding bandwidth is considered for UL sounding. More specifically,

in the example of FIG. 8, the P_F factor that determines the actual SRS sounding bandwidth is 2. As a result, only half of the configured bandwidth is considered for UL sounding.

Therefore, in order to identify the frequency domain starting position for partial frequency sounding, an additional parameter may be necessary.

[0062] FIG. 9 is the partial frequency sounding part of FIG. 8. To determine the frequency domain starting position for partial frequency as shown in FIG 9, new equations may be needed. In view of the above discussion, the equation for the length of the SRS sequence of FIG 6 may need to be updated as follows:

where, P_F ∈ {2, 3, 4, 8}.

[0063] In the above equation, if P_F is not configured, then the P_F would have a value of 1, and the equation would be the same as the equation for SRS sequence length captured in FIG. 6. In addition, in determining the starting position for partial frequency sounding, the definition of may be the same as in FIG. 6.

[0064] Furthermore, as mentioned above, an additional parameter may need to be

configured to identify the starting position of the sounding band using higher layer signaling or DCI. As a result, the equation for the frequency domain starting position for SRS partial frequency sounding of FIG 6 may need to be updated as follows:

[0065] In the above equation, if the parameter is not configured, then the would

have a value of 0, and the equation can be considered for determining the starting position and be the same as the equation for frequency domain starting position of FIG. 6. Note that, here is

given in physical resource elements (PREs). However, it is also possible that this parameter is given in physical resource blocks (PRBs). In that case, the equation may need to be modified accordingly. Optionally, may be configured as a common value to all ports. In other words,

Furthermore, this embodiment may be used for determining the frequency domain

starting position for both SRS hopping and non-hopping cases.

[0066] FIG. 10 shows another example of frequency domain starting position for partial frequency sounding according to one or more embodiments. In the example of FIG. 10,

is configured by way of higher-layer signaling or DCI only using bits, and the P_F is

configured to be 4 (hence 2 bits for configuring As a result, there may be four possible

frequency domain starting positions for SRS partial frequency sounding as illustrated in FIG. 10. [0067] Based on the configured value, the frequency domain starting position for

partial frequency of FIG. 10 can be calculated as follows:

[0068] In the above equation, if the parameter is not configured, then the would

have a value of 0. Optionally, the may be configured as a common value to all ports. In other

words,

[0069] Alternatively, in one or more embodiments, using higher layer signaling or DCI, the parameter is configured to identify the frequency domain starting position for partial frequency as follows:

[0070] In the above equation, if the parameter is not configured, then the would

words, Furthermore, this embodiment may be used for determining the frequency

domain starting position for both SRS hopping and non-hopping cases.

[0071] In view of the above, a new RRC parameter may need to be introduced to configure the value of γ. In the example of FIG. 11 , the new RRC parameter may be

with an integer value of 0-67 according to one or more embodiments. Note that this new RRC parameter can be configured per SRS resource or per SRS resource set, where each resource set may include multiple SRS resources transmitting at different symbols. In addition, this embodiment may be used for determining the frequency domain starting position for both SRS hopping and non-hopping cases.

[0072] FIG. 12 shows an example of a configuration of the parameter y according to one or more embodiments. Specifically, the value of γ can be implicitly configured by associating it with the DCI code point of the SRS request field of triggering DCI. As shown in FIG. 12, the DCI code point of SRS request field may have binary values of “00,” “01,” “10,” and “11” that correspond to γ_1, γ₂, and γ₃ (when the DCI code point of the SRS request field is “00,” no SRS resource sets are selected) configured using RRC signaling. The associated RRC parameter for configuring γ remains as defined previously. In addition, this

embodiment may be used for determining the frequency domain starting position for both SRS hopping and non-hopping cases.

[0073] FIG 13 shows an example of a configuration of the parameter y according to one or more embodiments. Specifically, as explained above, each SRS resource set may be associated with a particular γ value. As a result, by selecting appropriate SRS resource set(s) using DCI code point, NW can implicitly configure a particular value for parameter γ. As shown in the example of FIG. 13, each SRS resource set in the table has a particular γ value (for example, configured using RRC signaling). Then, by selecting a particular SRS resource set from the table, the NW can implicitly configure a value for y. Optionally, if aperiodic SRS (A-SRS) triggering is done using DCI without data/CSI scheduling, it is possible to repurpose unused fields in DCI formats 0_1/0_2 for indicating the γ value. In addition, this embodiment may be used for determining the frequency domain starting position for both SRS hopping and non-hopping cases.

[0074] FIG. 14 shows an example of a configuration of the parameter γ according to one or more embodiments. In this example, the value for parameter γ may be configured explicitly using code points for a new DCI field. For example, the code points for new DCI field may have binary values of “00,” “01,” “10,” and “11” that correspond to γ₁, γ₂, γ₃, and γ₄. In addition, this embodiment may be used for determining the frequency domain starting position for both SRS hopping and non-hopping cases.

[0075] FIG. 15 shows an example of a frequency domain starting position for partial frequency sounding according to one or more embodiments. Specifically, the UE may be configured with a set of contiguous RBs for SRS transmission within the configured SRS bandwidth considering a bitmap using higher layer signaling or DCI. As shown in the example of FIG. 15, and P_F = 2. Then, using the bitmap, the NW can select the set of

contiguous RB for SRS transmission. In this example, as illustrated by the SRS resource allocation, the set 000111111000 indicates that 1 represents SRS transmitting RB.

[0076] Additionally, in this example equation may be

used for determining the frequency domain starting position (same as the equation used for FIG. 6).

[0077] In the same example configured with a set of contiguous RBs for SRS transmission,

FIG. 15 shows an example where the index of the starting RB is 4. In this example, it is possible to dynamically change the index of the starting RB using DCI or higher-layer signaling such as MAC-CE, RRC, etc. . In addition, this embodiment may be used for determining the frequency domain starting position for both SRS hopping and non-hopping cases.

[0078] The above embodiments regarding SRS partial frequency sounding may only be applicable when the corresponding UE capability has been reported, and when the corresponding higher layer parameters are configured. For example, as part of its capability reporting, the UE reports whether it can perform SRS partial frequency sounding. As another example, as part of its capability reporting, the UE reports what P_F values it can support when configured with SRS partial frequency sounding. When the UE reports its capability, the NW can then configure SRS partial frequency sounding. Those skilled in the art will appreciate that additional scenarios may be applicable as corresponding higher layer parameters are added and/or configured.

[0079] Variations

[0080] The information, signals, and/or other elements described in this specification may be represented by using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, and so on, all of which may be referenced throughout the herein-contained description, may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or photons, or any combination of these. [0081] Also, information, signals, and so on can be output from higher layers to lower layers and/or from lower layers to higher layers. Information, signals, and so on may be input and/or output via a plurality of network nodes.

[0082] The information, signals, and so on that are input and/or output may be stored in a specific location (for example, a memory) or may be managed by using a management table. The information, signals, and so on to be input and/or output can be overwritten, updated, or appended. The information, signals, and so on that are output may be deleted. The information, signals, and so on that are input may be transmitted to another apparatus.

[0083] Reporting of information is by no means limited to the aspects/present embodiments described in this specification, and other methods may be used as well. For example, reporting of information may be implemented by using physical layer signaling (for example, downlink control information (DCI), uplink control information (UCI), higher layer signaling (for example, RRC (Radio Resource Control) signaling, broadcast information (master information block (MIB), system information blocks (SIBs), and so on), MAC (Medium Access Control) signaling and so on), and other signals and/or combinations of these.

[0084] Software, whether referred to as “ software” “firmware,” “middleware,” “microcode,” or “hardware description language,” or called by other terms, should be interpreted broadly to mean instructions, instruction sets, code, code segments, program codes, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, and so on.

[0085] Also, software, commands, information, and so on may be transmitted and received via communication media. For example, when software is transmitted from a website, a server, or other remote sources by using wired technologies (coaxial cables, optical fiber cables, twisted-pair cables, digital subscriber lines (DSL), and so on) and/or wireless technologies (infrared radiation, microwaves, and so on), these wired technologies and/or wireless technologies are also included in the definition of communication media.

[0086] The terms “system” and “network” as used in this specification are used interchangeably.

[0087] In the present specification, the terms “base station (BS),” “radio base station,” “eNB,” “gNB,” “cell,” “sector,” “cell group,” “carrier,” and “component carrier” may be used interchangeably. A base station may be referred to as a “fixed station,” “NodeB,” “eNodeB (eNB),” “access point,” “transmission point,” “receiving point,” “femto cell,” "small cell" and so on.

[0088] A base station can accommodate one or a plurality of (for example, three) cells (also referred to as "sectors"). When a base station accommodates a plurality of cells, the entire coverage area of the base station can be partitioned into multiple smaller areas, and each smaller area can provide communication services through base station subsystems (for example, indoor small base stations (RRHs (Remote Radio Heads))). The term “cell” or “sector” refers to part of or the entire coverage area of a base station and/or a base station subsystem that provides communication services within this coverage.

[0089] In the present specification, the terms “mobile station (MS),”

equipment (UE),” and “terminal” may be used interchangeably.

[0090] A mobile station may be referred to as, by a person skilled in the art, a “subscriber station,” “mobile unit,” “subscriber unit,” “wireless unit,” “remote unit,” “mobile device,” “wireless device,” “wireless communication device,” “remote device,” “mobile subscriber station,” “access terminal,” “mobile terminal,” “wireless terminal,” “remote terminal,” “handset,” “user agent,” “mobile client,” “client,” or some other appropriate terms in some cases.

[0091] Furthermore, the radio base stations in this specification may be interpreted as user terminals. For example, each aspect/present embodiment of the present disclosure may be applied to a configuration in which communication between a radio base station and a user terminal is replaced with communication among a plurali ty of user terminals (D2D (Device-to-Device)). In this case, the user terminals 20 may have the functions of the radio base stations 10 described above. In addition, wording such as “uplink” and “downlink” may be interpreted as “side.” For example, an uplink channel may be interpreted as a side channel.

[0092] Likewise, the user terminals in this specification may be interpreted as radio base stations. In this case, the radio base stations may have the functions of the user terminals described above.

[0093] Actions which have been described in this specification to be performed by a base station may, in some cases, be performed by upper nodes. In a network including one or a plurality of network nodes with base stations, it is clear that various operations that are performed to communicate with terminals can be performed by base stations, one or more network nodes (for example, MMEs (Mobility Management Entities), S-GW (Serving-Gateways), and so on may be possible, but these are not limiting) other than base stations, or combinations of these.

[0094] One or more embodiments illustrated in this specification may be used individually or in combinations, which may be switched depending on the mode of implementation. The order of processes, sequences, flowcharts, and so on that have been used to describe the aspects/present embodiments herein may be re-ordered as long as inconsistencies do not arise. For example, although various methods have been illustrated in this specification with various components of steps in exemplary orders, the specific orders that are illustrated herein are by no means limiting. [0095] One or more embodiments illustrated in the present disclosure may be applied to LTE (Long Term Evolution), LIE- A (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT- Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), New-RAT (Radio Access Technology), NR(New Radio), NX (New radio access), FX (Future generation radio access), GSM (registered trademark) (Global System for Mobile communications), CDMA 2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra- WideBand), Bluetooth (registered trademark), systems that use other adequate radio communication methods and/or next-generation systems that are enhanced based on these.

[0096] The phrase “based on” (or “on the basis of”) as used in this specification does not mean “based only on” (or “only on the basis of”), unless otherwise specified. In other words, the phrase “based on” (or “on the basis of”) means both “based only on” and “based at least on” (“only on the basis of” and “at least on the basis of”).

[0097] Reference to elements with designations such as “first,” herein does not generally limit the quantity or order of these elements. These designations may be used herein only for convenience, as a method for distinguishing between two or more elements. Thus, reference to the first and second elements does not imply that only two elements may be employed, or that the first element must precede the second element in some way.

[0098] The term “judging (determining)” as used herein may encompass a wide variety of actions. For example, “judging (determining)” may be interpreted to mean making “judgments (determinations)” about calculating, computing, processing, deriving, investigating, looking up (for example, searching a table, a database, or some other data structures), ascertaining, and so on. Furthermore, “judging (determining)” may be interpreted to mean making “judgments (determinations)” about receiving (for example, receiving information), transmitting (for example, transmitting information), input, output, accessing (for example, accessing data in a memory), and so on. In addition, “judging (determining)” as used herein may be interpreted to mean making “judgments (determinations)” about resolving, selecting, choosing, assuming, establishing, comparing, and so on. In other words, “judging (determining)” may be interpreted to mean making “judgments (determinations)” about some action.

[0099] The terms “connected” and “coupled,” or any variation of these terms as used herein mean all direct or indirect connections or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are “connected” or “coupled” to each other. The coupling or connection between the elements may be physical, logical, or a combination thereof. For example, “connection” may be interpreted as "access."

[00100] In this specification, when two elements are connected, the two elements may be considered “connected” or “coupled” to each other by using one or more electrical wires, cables and/or printed electrical connections, and, as some non-limiting and non-inclusive examples, by using electromagnetic energy having wavelengths in radio frequency regions, microwave regions, (both visible and invisible) optical regions, or the like.

[00101] In this specification, the phrase “A. and B are different” may mean that “A and B are different from each other.” The terms “separate,” “be coupled” and so on may be interpreted similarly.

[00102] Furthermore, the term "or" as used in this specification or in claims is intended to be not an exclusive disjunction.

[00103] Now, although the present invention has been described in detail above, it should be obvious to a person skilled in the art that the present invention is by no means limited to the embodiments described in this specification. The present invention can be implemented with various corrections and in various modifications, without departing from the spirit and scope of the invention defined by the recitations of claims. Consequently, the description in this specification is provided only for the purpose of explaining examples, and should by no means be construed to limit the invention according to the present invention in any way.

[00104] Alternative Examples [00105] The above examples and embodiments may be combined with each other, and various features of these examples may be combined with each other in various combinations. The invention is not limited to the specific combinations disclosed herein.

[00106] Although the disclosure has been described with respect to only a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that various other embodiments may be devised without departing from the scope of the present invention. Accordingly, the scope of the invention should be limited only by the attached claims.

Claims

CLAIMS What is claimed is:

1. A wireless communication method comprising: receiving, via downlink control information (DCI) or higher layer signaling, configuration information including a frequency sounding with a Sounding Reference Signal (SRS) configuration; configuring partial frequency sounding with SRS transmission based on the configuration information; and determining a frequency domain starting position of the SRS for partial frequency sounding.

2. The wireless communication method according to claim 1, wherein the downlink control information contains information relating to an uplink or downlink system bandwidth.

3. The wireless communication method according to claim 1, wherein determining the frequency domain starting position of the SRS is the same regardless of whether frequency hopping is enabled or disabled.

4. The wireless communication method according to claim 1, wherein the SRS is transmitted in contiguous resource blocks (RB) spanning one symbol in a time domain.

5. The wireless communication method according to claim 1, wherein a number of frequency partitions of the SRS depends on a number of sounding bands of the SRS.

6. The wireless communication method according to claim 1, further comprising dynamically changing the frequency domain starting position of the SRS via the DCI.

7. The wireless communication method according to claim 1, further comprising determining if frequency hopping is disabled by comparing a frequency hopping parameter to a number of frequency partitions of the SRS.

8. The wireless communication method according to claim 1, further comprising transmitting, as part of a capability report, information corresponding to a number of supported sounding bands within a bandwidth.

9. The wireless communication method according to claim 1 , further comprising receiving a first parameter given in physical resource elements that is configured to identify the frequency domain starting position of the SRS.

10. The wireless communication method according to claim 8, wherein the number of supported sounding bands is 2, 3, 4, or 8.

11. The wireless communication method according to claim 9, wherein the first parameter depends on a length of the SRS.

12. The wireless communication method according to claim 9, further comprising receiving a second parameter that is configured to identify the frequency domain starting position of a sounding band within the SRS.

13. The wireless communication method according to claim 12, wherein the first parameter is determined based upon the second parameter.

14. The wireless communication method according to claim 12, wherein the second parameter is specific to each SRS port.

15. The wireless communication method according to claim 12, wherein the second parameter is common to all SRS ports.

16. The wireless communication method according to claim 12, wherein the second parameter is configured using the DCI.

17. The wireless communication method according to claim 12, wherein the second parameter is configured using RRC.

18. The wireless communication method according to claim 12, wherein the second parameter corresponds to a DCI code point of an SRS request field of the DCI.

19. A terminal comprising: a receiver that receives, via downlink control information (DCI) or higher layer signaling, configuration information including a frequency sounding with Sounding Reference Signal (SRS) configuration; a processor configured to: configure partial frequency sounding with SRS transmission based on the configuration information; and determine a frequency domain starting position of the SRS for partial frequency sounding.

20. A system comprising: a terminal comprising: a first receiver that receives, via downlink control information (DCI) or higher layer signaling, configuration information including a frequency sounding with Sounding Reference Signal (SRS) configuration; a processor configured to: configure partial frequency sounding with SRS transmission based on the configuration information; and determine a frequency domain starting position of the SRS for partial frequency sounding; and a base station comprising: a transmitter that transmits the configuration information via DCI or higher layer signaling.