Transmission device, reception device, and methods thereof

Abstract

The present invention relates to a transmitting device (100) and a receiving device (300) of a wireless communication system (500). The transmitting device is used for transmitting one or more synchronization signals on a carrier to at least one receiving device, the frequency of a synchronization signal in the one or more synchronization signals is located on a first frequency grid, the carrier frequency of the carrier is deployed on a second frequency grid, and the carrier frequency of the carrier is located on the first frequency grid. The frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid; and transmitting an indication of the carrier frequency to at least one receiving device (300), where the indication comprises at least one integer. The receiving device (300) is configured to obtain a carrier frequency based on the at least one integer. The invention further relates to a corresponding method and to a computer program.

Description

[0001] This application is a divisional application. The application number of the original application is 201780093835.8, the filing date of the original application is August 10, 2017, and the entire content of the original application is incorporated herein by reference. Technical Field

[0002] The present invention relates to a transmitting device and a receiving device. In addition, the present invention also relates to corresponding methods and computer programs. Background Art

[0003] In 3GPP New Radio (NR), a Synchronization Signal (SS) block includes an NR-Primary Synchronization Signal (NR-PSS), an NR-Secondary Synchronization Signal (NR-SSS), and an NR-Physical Broadcast Channel (NR-PBCH). After detecting the SS block, a User Equipment (UE) can synchronize with a cell and obtain the cell ID and broadcast information of the cell. The broadcast information, for example, an NR-Master Information Block (NR-MIB), may further include information that enables the UE to detect an NR-Physical Downlink Shared Channel (NR-PDSCH) to obtain system information, such as Remaining System Information (RMSI) and Other System Information (OSI). The NR-PBCH may include information about control channel resources on which the UE can detect an NR-Physical Downlink Control Channel (NR-PDCCH) that schedules the RMSI via the NR-PDSCH. The NR-PBCH should be received over a large coverage area, so its payload should be minimized. Additional system information may be included in the RMSI or OSI.

[0004] In 3GPP NR, the synchronization signal block is located on a frequency grid (e.g., the center frequency of the SS block or SS is on the grid), and the frequency grid is a set of frequencies with a predefined interval between them. The frequency grid used for the synchronization signal block (denoted herein as the synchronization signal grid) can be different from the frequency grid used for the NR channel (denoted herein as the NR channel grid). The NR channel grid defines the carrier frequencies (e.g., the center frequency of the carrier) that can be used to deploy NR carriers. A carrier should be understood as an entity of a communication system that includes channels and signals for communication, and the carrier can be deployed in downlink and uplink communications.

[0005] The synchronization signal grid and the NR channel grid can be selected for different purposes. Thus, to reduce the search complexity of the UE, the synchronization signal grid can be sparser than the NR channel grid, for example. At least for initial cell selection, the UE searches for synchronization signals on the synchronization signal grid. The synchronization signal grid can be, for example, a multiple of 15 kHz, which is the subcarrier spacing (SCS) in NR, such as 300 kHz or 900 kHz. The NR system will provide different SCSs. For example, the SS can use SCSs of 15, 30, 120, or 240 kHz. Additional SCSs such as 60 kHz can be applicable to other channels and signals. In addition, the synchronization signal grid can be different in different frequency bands. For example, it can be 100 kHz in a frequency band where LTE and NR should coexist. Similarly, the NR channel grid can be different in different frequency bands. For example, it can be 100 kHz in a frequency band where LTE and NR should coexist, and may exhibit larger values in higher frequency bands with a larger amount of spectrum.

[0006] If the synchronization signal grid and the NR channel grid are different, it can be considered that the synchronization signal block is not located near the center frequency of the NR carrier, such as the carrier frequency. In addition, an NR carrier can include multiple synchronization signal blocks transmitted at different frequency positions. Thus, the synchronization signal grid can give the synchronization signal frequency position, which is a subset of the channel frequency, or the synchronization signal frequency position is completely misaligned with the channel frequency, or the synchronization signal frequency position is partially aligned with the channel frequency.

[0007] In the traditional system 3GPP LTE, the synchronization signal is located near the center frequency of the carrier, and the synchronization signal grid is the same as the channel grid. Thus, the UE can implicitly determine the carrier frequency from the frequency position of the detected synchronization signal. The carrier frequency information allows the UE to perform one or more of the following non-limiting tasks:

[0008] · Tune the oscillator to the carrier frequency.

[0009] · Perform receiver filtering.

[0010] ·Perform mobility measurements on cells characterized by cell ID and carrier frequency.

[0011] ·Detect multiple synchronization signal blocks and determine which carrier each of the multiple synchronization signal blocks belongs to.

[0012] ·Determine the position of the Physical Resource Blocks (PRBs) of the carrier.

[0013] ·Determine the position of the reference signal (RS).

[0014] ·Receive system information.

[0015] On the other hand, in 3GPP NR, the UE will not be able to implicitly determine the carrier frequency from the detected synchronization signal blocks because the synchronization signal raster and the NR channel raster may be different. Therefore, there is a problem of how to determine the NR carrier frequency in 3GPP NR. Summary of the Invention

[0016] An object of embodiments of the present invention is to provide a solution that alleviates or solves the deficiencies and problems of traditional solutions.

[0017] The above and further objects are solved by the solutions of the independent claims. Other advantageous implementations of the present invention can be obtained from the dependent claims.

[0018] According to a first aspect of the present invention, the above and other objects are achieved by a transmitting device of a wireless communication system, the transmitting device being configured to:

[0019] Transmit one or more synchronization signals on a carrier to at least one receiving device, wherein the frequency of the synchronization signal in the one or more synchronization signals is located on a first frequency raster, the carrier frequency of the carrier is deployed on a second frequency raster, and the frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first raster; and

[0020] Transmit an indication of the carrier frequency to at least one receiving device, wherein the indication includes at least one integer.

[0021] In an implementation of the first aspect, the frequency band where the carrier is located includes values determined from the first raster and the second raster, where the values represent frequency positions.

[0022] The frequency raster in the present disclosure can be understood as a set of frequencies with a predetermined interval between them. The first frequency raster may or may not be aligned with the second frequency raster. The frequency raster may depend on the frequency, that is, different frequency rasters may be used in different frequency bands.

[0023] The transmitting device according to the first aspect relates to a situation where there can be more than one synchronization signal in a carrier. In this case, the synchronization signals are located at different frequency positions on the first frequency grid. However, this does not exclude the case where there is only one synchronization signal in the carrier. It should also be noted that there can be multiple types of synchronization signals, such as a primary synchronization signal, a secondary synchronization signal, etc. Therefore, in this document, one or more synchronization signals can include different types of synchronization signals. It should also be understood that the situation where more than one synchronization signal is provided on a carrier and these multiple synchronization signals are located at different frequency positions on the first frequency grid includes the following situation: one synchronization signal can include different types of synchronization signals (e.g., NR-PSS and NR-SSS), and these different types of synchronization signals are separated in time (e.g., in different OFDM symbols) but use the same frequency position (i.e., the same grid value). Thus, an example is that the first pair of synchronization signals NR-PSS_1 and NR-SSS_1 have the same frequency position, which is different from the frequency position of one of the synchronization signals in the second pair of synchronization signals NR-PSS_2 and NR-SSS_2. In addition, it should be understood that the carrier can also only include the first pair of synchronization signals NR-PSS_1 and NR-SSS_1 with the same frequency position.

[0024] It should also be noted that the carrier frequency can be equal to or not equal to the center frequency of the carrier. For a receiving device that cannot receive a wideband carrier, transmission and / or reception can be performed on a part of the carrier. This part of the wideband carrier can be regarded as the carrier of a certain receiving device, where its carrier frequency is restricted within this part of the wideband carrier, and this part of the wideband carrier may not be the center frequency of the carrier.

[0025] The transmitting device according to the first aspect provides many advantages compared to traditional solutions. The advantage of the transmitting device is that it allows the receiving device to determine the carrier frequency and potentially determine the frequency position of the synchronization signal within the carrier and one or both of the PRB and reference signal (RS) frequency positions.

[0026] In an implementation of the transmitting device according to the first aspect, the frequency of the synchronization signal is the center frequency of the synchronization signal or the carrier. In one example, the center frequency and the carrier frequency are different frequencies.

[0027] In an implementation of the transmitting device according to the first aspect, the at least one integer is a channel number.

[0028] The advantage of this implementation is that it reduces the signaling overhead for indicating the carrier frequency because the mapping between the carrier frequency and the channel number is known. In addition, the carrier frequency can be uniquely determined from the channel number.

[0029] In an implementation of the transmitting device according to the first aspect, the channel number is associated with a unique carrier frequency.

[0030] The advantage of this implementation is that it provides a simple way to clearly determine the carrier frequency, thus reducing the complexity of the receiver.

[0031] In an implementation of the transmitting device according to the first aspect, the spectrum of the wireless communication system is divided into a plurality of non-overlapping frequency bands, and the channel number is associated with a unique carrier frequency in the frequency band.

[0032] The advantage of this implementation is that fewer bits are required to encode the information about the carrier frequency because the range of the channel number values can be reduced.

[0033] In an implementation of the transmitting device according to the first aspect, the range of the channel number depends on the frequency band.

[0034] The advantage of this implementation is that the signaling overhead of the channel number can be reduced. For example, in a frequency band with a large amount of available spectrum, the frequency grid may contain fewer frequencies and thus fewer channel numbers.

[0035] In an implementation of the transmitting device according to the first aspect, the frequency interval between two adjacent synchronization signals is a multiple of the subcarrier interval of the wireless communication system, and the first frequency grid is a subset of the second frequency grid.

[0036] The advantage of this implementation is that the synchronization signal is aligned with the subcarriers of other channels and the signals of the carrier.

[0037] In an implementation of the transmitting device according to the first aspect, the at least one integer is a relative channel number.

[0038] The advantage of this implementation is that the overhead of transmitting the carrier frequency can be further reduced.

[0039] In an implementation of the transmitting device according to the first aspect, the relative channel number depends on the maximum carrier bandwidth of the wireless communication system.

[0040] The advantage of this implementation is that, considering that the synchronization signal cannot be located further away from the carrier frequency compared to the maximum carrier bandwidth, the overhead of transmitting the carrier frequency can be further reduced.

[0041] In an implementation of the transmitting device according to the first aspect, the range of the relative channel number depends on the maximum carrier bandwidth.

[0042] The advantage of this implementation is that, considering that the synchronization signal cannot be located further away from the carrier frequency compared to the maximum carrier bandwidth, the overhead of transmitting the carrier frequency can be further reduced.

[0043] In the implementation of the transmitting device according to the first aspect, the maximum carrier bandwidth depends on the frequency.

[0044] The advantage of this implementation is that a wider carrier bandwidth is provided only in the frequency bands with a large amount of available spectrum.

[0045] In the implementation of the transmitting device according to the first aspect, the at least one integer is a first index and a second index. The first index indicates a first frequency position relative to the frequency of the synchronization signal, and the second index indicates a second frequency position relative to the first frequency position.

[0046] The advantage of this implementation is that the overhead of transmitting the carrier frequency can be further reduced.

[0047] In the implementation of the transmitting device according to the first aspect, the first frequency position is given in terms of the number of physical resource blocks, and the second frequency position is given in terms of the resolution of the second frequency grid.

[0048] The advantage of this implementation is that the overhead of transmitting the carrier frequency can be further reduced, and the synchronization signal can be frequency-aligned with other channels and signals located in the resource blocks.

[0049] In the implementation of the transmitting device according to the first aspect, the first frequency position is given in terms of the resolution of the first frequency grid, and the second frequency position is given in terms of the resolution of the second frequency grid.

[0050] The advantage of this implementation is that, considering that the first grid may be sparser than the second grid, the overhead of transmitting the carrier frequency can be further reduced.

[0051] In the implementation of the transmitting device according to the first aspect, the transmitting device (100) is further configured to:

[0052] Transmit the indication in at least one of the following: Master Information Block (MIB), Remaining System Information (RMSI), Other System Information (OSI), and Radio Resource Control (RRC).

[0053] One advantage of this implementation is that the transmission signal is carried out in a channel with the following capabilities: containing more information, that is, information about what the synchronization signal can do. Encoding additional information in the synchronization signal increases the complexity of the receiver because it is usually based on the synchronization sequence, while the MIB, RMSI, OSI, and RRC signaling are carried in channels more suitable for information transmission.

[0054] According to a second aspect of the present invention, the above object and other objects are achieved by a receiving device of a wireless communication system, and the receiving device is configured to:

[0055] Receive one or more synchronization signals on a carrier from a transmitting device, wherein the frequencies of the synchronization signals in the one or more synchronization signals are located on a first frequency grid, the carrier frequency of the carrier is deployed on a second frequency grid, and the frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid;

[0056] Receive an indication of the carrier frequency from the transmitting device, wherein the indication includes at least one integer; and

[0057] Obtain the carrier frequency based on the at least one integer.

[0058] In an implementation of the second aspect, the frequency band where the carrier is located includes values determined from the first grid and the second grid.

[0059] The receiving device according to the second aspect provides many advantages over traditional solutions. One advantage is that it allows the receiving device to determine the carrier frequency and potentially determine the frequency positions of the synchronization signals within the carrier and one or both of the Physical Resource Block (PRB) and Reference Signal (RS) frequency positions.

[0060] In an implementation of the receiving device according to the second aspect, the spectrum of the wireless communication system is divided into a plurality of non - overlapping frequency bands, and the at least one integer is associated with the frequency band, and the receiving device is further configured to:

[0061] Map the at least one integer based on the frequency band so as to derive the carrier frequency.

[0062] According to a third aspect of the present invention, the above object and other objects are achieved by a method of a transmitting device, and the method includes:

[0063] Transmit one or more synchronization signals on a carrier to at least one receiving device, wherein the frequencies of the synchronization signals in the one or more synchronization signals are located on a first frequency grid, the carrier frequency of the carrier is deployed on a second frequency grid, and the frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid; and

[0064] Transmit an indication of the carrier frequency to the at least one receiving device, wherein the indication includes at least one integer.

[0065] In an implementation of the third aspect, the frequency band where the carrier is located includes values determined from the first grid and the second grid.

[0066] In an implementation of the third aspect, the method further includes obtaining at least one synchronization signal before transmitting the at least one synchronization signal.

[0067] The method according to the third aspect can be extended to an implementation corresponding to the implementation of the transmitting device according to the first aspect. Therefore, the implementation of the method includes the features of the corresponding implementation of the transmitting device.

[0068] The advantages of the method according to the third aspect are the same as the advantages of the corresponding device claims according to the first aspect.

[0069] According to a fourth aspect of the present invention, the above and other objects are achieved by a method of a receiving device, the method including:

[0070] Receiving one or more synchronization signals on a carrier from a transmitting device, wherein the frequencies of the synchronization signals in the one or more synchronization signals are located on a first frequency grid, the carrier frequency of the carrier is deployed on a second frequency grid, and the frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid;

[0071] Receiving an indication of the carrier frequency from the transmitting device, wherein the indication includes at least one integer; and

[0072] Obtaining the carrier frequency based on the at least one integer.

[0073] In an implementation of the fourth aspect, the frequency band where the carrier is located includes values determined from the first grid and the second grid.

[0074] The method according to the fourth aspect can be extended to an implementation corresponding to the implementation of the receiving device according to the second aspect. Therefore, the implementation of the method includes the features of the corresponding implementation of the receiving device.

[0075] The advantages of the method according to the fourth aspect are the same as the advantages of the corresponding device claims according to the second aspect.

[0076] The present invention also relates to a computer program, represented in code form, which, when run by a processing device, causes the processing device to execute any method according to the present invention. Furthermore, the present invention also relates to a computer program product comprising a computer-readable medium and the computer program, wherein the computer program is included in the computer-readable medium and comprises one or more of the following group: ROM (Read-Only Memory), PROM (Programmable ROM), EPROM (Erasable PROM), flash memory, EEPROM (Electrically-Erasable PROM), and hard disk drive.

[0077] Further applications and advantages of the present invention will be apparent from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] The drawings are intended to illustrate and explain different embodiments of the present invention, wherein:

[0079] Figure 1 shows a transmitting device according to an implementation of the present invention;

[0080] Figure 2 shows a method according to an implementation of the present invention;

[0081] Figure 3 shows a receiving device according to an implementation of the present invention;

[0082] Figure 4 shows another method according to an implementation of the present invention;

[0083] Figure 5 shows a wireless system according to an implementation of the present invention;

[0084] Figure 6 shows an enumeration of carrier frequencies according to an implementation of the present invention;

[0085] Figure 7 shows an indication of carrier frequencies by using a first index and a second index according to an implementation of the present invention;

[0086] Figure 8 a) and 8b) show a PRB grid within a frequency band according to an implementation of the present invention. DETAILED DESCRIPTION

[0087] Figure 1 shows a transmitting device 100 according to an implementation of the present invention. In Figure 1In the implementation shown, the transmitting device 100 includes a processor 102, a transceiver 104, and a memory 106. The processor 102 is coupled to the transceiver 104 and the memory 106 through a communication device 108 known in the art. The transmitting device 100 can be used for wireless and wired communications in wireless and wired communication systems respectively. The antenna 110 coupled to the transceiver 104 has wireless communication capabilities, while the wired communication interface 112 coupled to the transceiver 104 has wired communication capabilities.

[0088] In the present disclosure, the transmitting device 100 is used to perform certain actions and / or functions according to the present invention. It should be understood that the transmitting device 100 includes corresponding means for performing the said actions and / or functions, for example, the processor 102 and the transceiver 104.

[0089] Figure 1 The transmitting device 100 in is used to send one or more synchronization signals (SS) on a carrier to at least one receiving device 300, wherein the frequency of the synchronization signal in the one or more synchronization signals is located on a first frequency grid, the carrier frequency of the carrier is deployed on a second frequency grid, and the frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid. The transmitting device 100 is also used to send an indication of the carrier frequency to at least one receiving device 300. The indication here includes at least one integer.

[0090] Figure 2 shows that it can be in as Figure 1 shown in the flowchart of the corresponding method 200 that can be executed in the transmitting device 100. The method 200 includes 202: sending one or more synchronization signals on a carrier to at least one receiving device 300, wherein the frequency of the synchronization signal in the one or more synchronization signals is located on a first frequency grid, the carrier frequency of the carrier is deployed on a second frequency grid, and the frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid. The method further includes 204: sending an indication of the carrier frequency to at least one receiving device 300. The indication includes at least one integer.

[0091] Figure 3 shows a receiving device 300 according to an implementation of the present invention. In Figure 3 the implementation shown, the receiving device 300 includes a processor 302, a transceiver 304, and a memory 306. The processor 302 is coupled to the transceiver 304 and the memory 306 through a communication device 308 known in the art. The receiving device 300 further includes an antenna 308 coupled to the transceiver 302, which means that the receiving device 300 is used for wireless communication in a wireless communication system.

[0092] In the present disclosure, the receiving device 300 is used to perform certain actions and / or functions according to the present invention. It should be understood that the receiving device 300 includes corresponding means for performing the said actions and / or functions, such as a processor 302 and a transceiver 304.

[0093] The receiving device 300 is used to receive one or more synchronization signals on a carrier from the transmitting device 100. Among them, the frequency of the synchronization signal in the one or more synchronization signals is located on a first frequency grid, the carrier frequency of the carrier is deployed on a second frequency grid, and the frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid. The receiving device 300 is also used to receive an indication of the carrier frequency from the transmitting device 100, where the indication includes at least one integer. The receiving device 300 is also used to obtain the carrier frequency based on the at least one integer. Examples of how to obtain the carrier frequency according to the at least one integer are explained in the following disclosure.

[0094] Figure 4 shows that it can be in as Figure 3 shown in the flowchart of the corresponding method 400 that can be executed in the receiving device 300. The method 400 includes 402: receiving one or more synchronization signals on a carrier from the transmitting device 100. Among them, the frequency of the synchronization signal in the one or more synchronization signals is located on a first frequency grid, the carrier frequency of the carrier is deployed on a second frequency grid, and the frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid. The method 400 also includes 404: receiving an indication of the carrier frequency from the transmitting device 100, where the indication includes at least one integer. The method 400 also includes 406: obtaining the carrier frequency based on the at least one integer.

[0095] Figure 5 shows a wireless communication system 500 according to an implementation manner of the present invention. The wireless communication system 500 includes a transmitting device 100 and a receiving device 300 for operating in the wireless communication system 500. In this example, a downlink (DL) scenario is shown, which means that the transmitting device 100 is part of a network node (such as a base station), and the receiving device 300 is part of a client device (such as a UE). In the wireless communication system 500, a synchronization signal (SS) is sent by the transmitting device 100 and received by the receiving device 300. For simplicity, Figure 5 the shown wireless communication system 500 only includes one transmitting device 100 and one receiving device 300. However, without departing from the scope of the present invention, the wireless communication system 500 may include any number of transmitting devices and any number of receiving devices.

[0096] It should be noted that the present solution is not limited to the downlink scenario, and thus can be implemented in the uplink (UL), or in both the downlink and the uplink. Therefore, depending on the implementation, the transmitting device 100 and the receiving device 300 can be associated with network nodes and / or client devices.

[0097] In one example, the spectrum of the wireless communication system 500 is divided into a plurality of non-overlapping frequency bands, and at least one integer is associated with the frequency band. In this case, the receiving device 300 is used to map at least one integer based on the frequency band in order to obtain the carrier frequency.

[0098] The indication of the carrier frequency in this document can be sent from the transmitting device 100 to the receiving device 300 using several different methods, for example, depending on when the receiving device 300 needs to know the carrier frequency during the access procedure. Therefore, the transmitting device 100 is used to send the indication in at least one of the following: the master information block (MIB), the remaining system information (RMSI), the other system information (OSI), and the radio resource control (RRC).

[0099] The MIB provides the fastest way to transmit carrier frequency information in the broadcast channel. On the other hand, it is beneficial to minimize the payload of the broadcast channel.

[0100] The RMSI can be included in the NR-PDSCH scheduled by the NR-PDCCH, where the information related to the configuration of the NR-PDCCH / NR-PDSCH is included in the NR-MIB. If the carrier frequency information is included in the RMSI, it means that the RMSI should be detectable without knowing the carrier frequency. Therefore, the resources in the NR-PDCCH / NR-PDSCH used to determine the RMSI should not depend on the carrier frequency, but can be determined from the NR-SS and / or the NR-PBCH.

[0101] The OSI can be included in the NR-PDSCH scheduled by the NR-PDCCH, where the information related to the configuration of the NR-PDCCH / NR-PDSCH is included in the NR-MIB and / or the RMSI. If the carrier frequency information is included in the OSI, it means that the OSI should be detectable without knowing the carrier frequency. Therefore, the resources in the NR-PDCCH / NR-PDSCH used to determine the OSI should not depend on the carrier frequency, but can be determined from the NR-SS and / or the NR-PBCH.

[0102] The present invention is also applicable if the indication of the carrier frequency is jointly sent through any combination of the NR-MIB, the RMSI, and the OSI.

[0103] When RRC signaling is used to send a signal and the carrier frequency is used to define a cell in the higher layer for mobility measurement, a cell description including the cell ID and the carrier frequency can be sent by RRC. In this case, since the RRC signaling is carried by the NR-PDSCH, the overhead of sending the carrier frequency is less important.

[0104] In the following, possible implementations of the present invention are described and explained. In this regard, a wireless communication system 500 is considered, in which the synchronization signal can be placed on the first frequency grid {f SS,i} (i.e., a set of frequencies), resulting in a minimum spacing of |f SS,i - f SS,i+1 | = Δf SS Hz, and the carrier can be placed on the second frequency grid {f C,i}, resulting in a minimum spacing of |f C,i - f C,i+1 | = Δf C Hz. In such a system, the first frequency grid and the second frequency grid can depend on the frequency band, i.e., the values Δf SS (f SS,i ) and Δf C (f C,i ) may not be constant and can be a function of frequency. However, it should be noted that the present invention is not limited to the above type of wireless communication system.

[0105] In one implementation of the present invention, the carrier frequency is represented as a channel number C. In this case, the mapping from the channel number to the carrier frequency, C → f C,i , can be predefined and known to the receiving device 300. For example, the mapping can be performed using a closed-form expression, such as: F DL = F DL_low + Δf C (C - N offs_DL ), where the constants F DL_low and N offs_DL can be predefined and F DL = f C,i .

[0106] In one implementation, N channel frequencies can be enumerated according to 0 ≤ C ≤ N - 1. In this case, it is not required that the synchronization signal frequency position is a subset of the channel frequencies, i.e., may not hold. On the other hand, this implementation does not exclude that the synchronization signal frequency position is a subset of the channel frequencies.

[0107] In one example, when the carrier frequency is represented as a channel number C, a single enumeration is applied across all frequency bands, meaning that each channel number is associated with a unique carrier frequency. That is, the mapping from channel number to carrier frequency C → f C,i is a one-to-one mapping, and each value of the channel number C is associated with a unique frequency f C,i associated. This implementation is shown in the top axis of Figure 6 where the frequency band is divided into two bands, namely band A and band B, and 8 carrier frequencies are shown. In the top axis, a single enumeration is applied, so 3 bits are needed to represent the carrier frequency. This provides a simple way to unambiguously determine the carrier frequency, but requires a set of channel numbers of size N to include all carrier frequencies of the system. The mapping can be band-specific and predefined, e.g., F DL = F DL_low + Δf C (C)(C - N offs_DL ) where the grid value is a function of the channel number, i.e., Δf C (C).

[0108] In another example, when the carrier frequency is represented as a channel number C, multiple enumerations are applied across all frequency bands. This can be achieved by dividing the spectrum into predefined non-overlapping frequency bands and performing an enumeration independently for each band. Thus, the spectrum of the wireless communication system 500 is divided into multiple non-overlapping frequency bands, where the channel number C is associated with a unique carrier frequency within the band.

[0109] Thus, the mapping from channel number to carrier frequency C → f C,i is a one-to-many mapping, and each value of the channel number C can be associated with more than one frequency f C,i associated. However, this still provides a unique mapping C → f C,i to the receiving device 300 because the receiving device 300 knows in which frequency band it is detecting the synchronization signal block. However, it should be noted that the mapping can be different in different frequency bands, e.g., the mapping can be band-specific and predefined, e.g., F DL = F DL_low + Δf C (C)(C - N offs_DL ) where the grid value is a function of the channel number, Δf C (C). This implementation is shown in Figure 6is shown in the bottom axis, where the enumeration is repeated for each of the bands A and B. Thus, in this case, 2 bits are required to represent the carrier frequency. The advantage of this is that less bits are required to encode the information about the carrier frequency. For example, when N frequency positions are divided into M frequency bands, it is reduced from log2N bits to log2(N / M) bits. One purpose of this is to minimize the number of bits required to indicate the carrier frequency, because the number of carrier frequencies can be very large, and for a given channel, a larger signaling overhead results in a smaller area coverage (i.e., a higher code rate). Area coverage is particularly important for channels used for initial access, such as synchronization signals, broadcast signals, and channels for transmitting system information. When the carrier frequency is used together with the cell ID, for example, to define a measurement object, further information about the designated frequency band may be required so that the receiving device 300 can uniquely determine the correct carrier frequency.

[0110] In one implementation, the channel number C can be indicated using log2SC bits in the MIB, where SC is the total number of subcarriers within a given frequency band. This provides the maximum deployment flexibility at the cost of signaling overhead.

[0111] Other possible implementations of the present invention apply when the frequency interval between two adjacent synchronization signals is a multiple of the subcarrier interval of the wireless communication system 500, and the first frequency grid is a subset of the second frequency grid. In other words, the distance Δf between the frequency positions of two adjacent synchronization signals SS is a multiple of the subcarrier spacing (SCS) supported by the wireless communication system 500. In addition, the synchronization signal frequency positions are a subset of the channel frequencies, that is, here, the multiple of the SCS can include the distance Δf between the two synchronization signal frequency positions SS is n times the PRB bandwidth B (which is also a multiple of the SCS) for a given SCS, Δf SS = n·B, where n is a positive integer.

[0112] In one implementation, when the above assumptions hold, using the relative channel number ΔC to indicate the carrier frequency is disclosed herein, that is, -(N - 1) ≤ ΔC ≤ N - 1. In this case, the receiving device 300 detects the synchronization signal block frequency position f SS,i , which is located on the channel grid and determines the relative carrier frequency ΔC→Δf based on a predefined mapping rule C,i . For example, Δf C,i can be a multiple of the carrier frequency grid Δf C = |f C,i - f C,i+1 |. The carrier frequency is derived based on the above relative channel number, f SS,i + ΔfC,i because It follows that the number of bits representing the relative channel number can be log2(2N + 1), where N is the number of synchronization signal frequencies.

[0113] In another implementation, when the above assumption holds, it is disclosed herein to use the relative channel number ΔC to indicate the carrier frequency, i.e., -(N - 1) ≤ ΔC ≤ N - 1. In this case, the receiving device 300 is informed of the frequency position f WB , which is located on the channel grid and determines the relative carrier frequency ΔC → Δf based on a predefined mapping rule C,i . For example, Δf C,i can be a multiple of the carrier frequency grid Δf C = |f C,i - f C,i+1 |. The carrier frequency is derived based on the above relative channel number, f WB + Δf C,i . Because f WB ∈{f C,i}, it follows that the number of bits representing the relative channel number can be log2(2N + 1), where N is the number of channel grids in this frequency band.

[0114] One advantage that can be recognized is that the number N can be determined from the maximum carrier bandwidth, i.e., the maximum number of carrier frequencies that can be within the carrier. It can be recognized that this will provide the minimum value of N because the carrier frequency cannot be located further away from the synchronization signal block frequency relative to the carrier bandwidth. For example, assuming the maximum carrier bandwidth is W Hz, it follows that using ceiling, such that represents the smallest integer greater than x. In addition, the maximum carrier bandwidth can depend on the frequency band. For example, very wide carriers can be used in higher frequency bands. Also, the second grid may be different in different frequency bands. Therefore, the number N can depend on the frequency. For example,

[0115] if in addition to the requirements to be placed on the first grid and the position of the synchronization signal block within the carrier, other limitations can be assumed, the number N can be further reduced. For example, assuming that the distance between the carrier frequency and the synchronization channel block frequency f SS，i cannot exceed X Hz (where X is less than the maximum carrier bandwidth), it follows that

[0116] the number N can then be individually enumerated and obtained based on all the synchronization signal frequencies in the wireless communication system 500.

[0117] In another case, the quantity N can be enumerated multiple times. This is achieved by dividing the spectrum into predefined non - overlapping frequency bands and performing the enumeration independently for each band. Thus, the mapping ΔC→Δf C,i is a one - to - many mapping, and each value ΔC can be associated with more than one frequency Δf C,i However, this still provides a unique mapping ΔC→f for the receiving device 300 C,i because the receiving device 300 knows in which frequency band it is detecting the synchronization signal block. The advantage of this is that fewer bits are required to encode the information about the carrier frequency. For example, when N frequency positions are divided into M frequency bands, it is reduced from log2(2N + 1) bits to log2(2N / M) bits. When the carrier frequency is used together with the cell ID, for example, to define a measurement object, further information about the specified frequency band may be required so that the receiving device 300 can uniquely determine the correct carrier frequency.

[0118] In another implementation of the present invention, when the above - mentioned assumptions hold, the carrier frequency is indicated using a first index and a second index. The first index indicates a first frequency position relative to the frequency position of the synchronization signal, and the second index indicates a second frequency position relative to the first frequency position indicated by the first index.

[0119] In a possible implementation of the present invention, the first frequency position is given in terms of the number of PRBs or the resolution of the first frequency grid. Thus, the second frequency position is given in terms of the resolution of the second frequency grid. The resolution of the grid here refers to the frequency interval between two adjacent frequencies of the grid.

[0120] In one implementation of this implementation, it is assumed that for a given SCS, the distance Δf SS between two synchronization signal frequency positions is n times the PRB bandwidth B, Δf SS = n·B, where n is a positive integer. Thus, the first index -(M - 1)≤δ≤M - 1 determines the offset relative to the detected synchronization signal frequency position where the above - mentioned carrier frequency is located. For example, the above - mentioned offset is expressed in terms of the PRB bandwidth step B or the first frequency grid step (which can also be expressed as the SS grid step, or SS grid resolution). In one implementation, the value M determines the number of PRBs or the first frequency grid step Δf SS applicable to the above - mentioned frequency band. In another implementation, the value M determines the number of PRBs or the first frequency grid step Δf SSThe number. It can be recognized that this can reduce the value of M because the distance between the synchronization signal and the carrier frequency cannot be greater than the maximum carrier bandwidth (which can depend on the frequency band). The second index provides the position of the carrier frequency within the PRB or within the frequency region defined by two consecutive synchronization signal frequencies. For example, in Figure 7 , the carrier frequency is located 3 PRBs (second index) away from the detected synchronization signal block frequency (i.e., f SS,i ), and the carrier frequency is located at the second carrier frequency (first index) at a distance from the position obtained from the first index. Assuming that the first index has a step or granularity greater than the second frequency grid, and assuming the distance, there are limitations on how many PRBs or how many synchronization signal grid positions the above-mentioned synchronization signal block frequency at which the above-mentioned carrier frequency can be located, for example, limited by the maximum carrier bandwidth, which enables reducing the number of bits used to represent the carrier frequency.

[0121] As a result of the present invention, once the receiving device 300 determines the carrier frequency, the receiving device 300 can determine the PRB frequency position and / or RS frequency position within the carrier, assuming that their frequency positions are associated with the carrier frequency. For example, if the system bandwidth is sent to the receiving device 300 using the carrier frequency and the system bandwidth, the PRB position within the carrier frequency band can be determined. For each system bandwidth, a PRB position is determined.

[0122] In one example, if the total number of PRBs in frequency band Z is odd, the center frequency of PRB#(Z + 1) / 2 is aligned with the carrier frequency. In this case, the PRB position is as shown in Figure 8 (a). If the total number of PRBs in frequency band (Z) is even, the carrier frequency is located between PRB#(Z / 2) and PRB#(Z / 2 + 1), and the PRBs are located at the positions as shown in Figure 8 (b).

[0123] The advantage of aligning the PRBs within the carrier according to a given frequency (such as the above-mentioned carrier frequency) is that the PRBs of multiple carriers become aligned in frequency position. This enables the use of techniques for inter-cell interference coordination.

[0124] Depending on the technology and terminology used, the network nodes in this document can also be represented as wireless network nodes, access network nodes, access points, or base stations, such as a Radio Base Station (RBS). In some networks, a wireless base station can be referred to as a transmitter, "eNB", "eNodeB", "NodeB", or "B node". Wireless network nodes can have different categories based on transmission power and cell size. For example, macro eNodeB, home eNodeB, or pico base station. A wireless network node can be a Station (STA), which is any device that includes an IEEE 802.11 - compliant Media Access Control (MAC) and Physical Layer (PHY) interface with a Wireless Medium (WM). A wireless network node can also be a base station corresponding to the fifth generation (5G) wireless system.

[0125] The client device in this document can be represented as a user device, user equipment (UE), mobile station, Internet of Things (IoT) device, sensor device, wireless terminal, and / or mobile terminal, which is capable of wireless communication in a wireless communication system (sometimes also referred to as a cellular wireless system). UE can also refer to a mobile phone, cellular phone, computer tablet, or laptop with wireless capabilities. The UE in the context of this disclosure can be, for example, a portable, pocket-storable, handheld, computer-included, or vehicle-mounted mobile device that is capable of communicating voice and / or data with another entity (such as another receiver or server) through a wireless access network. A UE can be a Station (STA), which is any device that includes an IEEE 802.11 - compliant Media Access Control (MAC) and Physical Layer (PHY) interface with a Wireless Medium (WM). UE can also be used for communication in 3GPP-related LTE and LTE-Advanced, WiMAX and its evolution, and fifth-generation wireless technologies (such as New Radio).

[0126] In addition, any method according to an embodiment of the present invention can be implemented in a computer program having a code device, which, when run by a processing device, causes the processing device to perform the steps of the method. The computer program is included in a computer-readable medium of a computer program product. The computer-readable medium can substantially include any memory, for example, ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), flash memory, EEPROM (Electrically Erasable PROM), or a hard disk drive.

[0127] In addition, those skilled in the art recognize that network nodes and client devices include necessary communication capabilities in the form of, for example, functions, devices, units, elements, etc. for implementing the present solution. Examples of other such devices, units, elements, and functions are: processors, memories, buffers, control logic, encoders, decoders, rate matchers, de-rate matchers, mapping units, multipliers, decision units, selection units, switches, interleavers, de-interleavers, modulators, demodulators, inputs, outputs, antennas, amplifiers, receiver units, transmitter units, DSPs, MSDs, TCM encoders, TCM decoders, power supply units, power feeding devices, communication interfaces, communication protocols, etc., which are appropriately arranged together to implement the solution of the present invention.

[0128] In particular, the processors of network nodes and client devices can include, for example, one or more instances of a central processing unit (CPU), a processing unit, a processing circuit, a processor, an application specific integrated circuit (ASIC), a microprocessor, or other processing logic that can interpret and execute instructions. Thus, the expression "processor" can represent a processing circuit including multiple processing circuits, such as any one, part, or all of the processing circuits mentioned above. The processing circuit can also perform data processing functions for input, output, and processing of data, where the data includes data buffering and device control functions, such as call processing control, user interface control, etc.

[0129] Finally, it should be understood that the present invention is not limited to the above embodiments, nor to all embodiments included within the scope of the appended independent claims.

Claims

1. A method for a transmitting device, the method comprising: Transmitting one or more synchronization signals on a carrier to at least one receiving device, wherein the frequency of the synchronization signal in the one or more synchronization signals is located on a first frequency grid, and the carrier frequency of the carrier is deployed on a second frequency grid; and Transmitting an indication of the carrier frequency to the at least one receiving device, wherein the indication includes at least one integer.

2. A method for a receiving device, the method comprising: Receiving one or more synchronization signals on a carrier from a transmitting device, wherein the frequency of the synchronization signal in the one or more synchronization signals is located on a first frequency grid, and the carrier frequency of the carrier is deployed on a second frequency grid; Receiving an indication of the carrier frequency from the transmitting device, wherein the indication includes at least one integer; and Obtaining the carrier frequency based on the at least one integer.

3. The method according to claim 1 or 2, wherein The at least one integer is a channel number.

4. The method according to claim 3, wherein, The channel number is associated with a unique carrier frequency.

5. The method according to claim 3 or 4, wherein The spectrum of the wireless communication system is divided into a plurality of non-overlapping frequency bands, wherein the channel number is associated with a unique carrier frequency in the frequency band.

6. The method according to claim 5, wherein, The range of the channel number depends on the frequency band.

7. The method according to any one of the preceding claims 1-6, wherein, The frequency interval between two adjacent synchronization signals is a multiple of the subcarrier interval of the wireless communication system.

8. The method according to any one of the preceding claims 1-7, wherein, The first frequency grid is a subset of the second frequency grid.

9. The method according to any one of claims 1-2, 7-8, wherein, The at least one integer is a relative channel number.

10. The method according to claim 9, wherein, The relative channel number depends on the maximum carrier bandwidth of the wireless communication system.

11. The method according to claim 10, wherein, The range of the relative channel number depends on the maximum carrier bandwidth.

12. The method according to claim 10 or 11, wherein The maximum carrier bandwidth depends on the frequency.

13. The method according to any one of claims 1-2, 7-8, wherein The at least one integer is a first index and a second index, the first index indicating a first frequency position relative to the frequency of the synchronization signal, and the second index indicating the position of the carrier frequency relative to the first frequency position.

14. The method according to claim 13, wherein, The first frequency position is given in terms of the number of physical resource blocks, and the second frequency position is given in terms of the resolution of the second frequency grid.

15. The method according to claim 13, wherein The first frequency position is given in terms of the resolution of the first frequency grid, and the second frequency position is given in terms of the resolution of the second frequency grid.

16. The method according to any one of the preceding claims 1-15, Transmitting the indication in at least one of: a master information block (MIB), remaining system information (RMSI), other system information (OSI), and radio resource control (RRC).

17. The method according to claim 1 or 2, wherein the frequency band where the carrier is located includes values determined from the first grid and the second grid.

18. The method according to claim 1 or 2, the method further comprising obtaining at least one synchronization signal before transmitting the at least one synchronization signal.

19. The method according to claim 1 or 2, wherein, The frequencies of two different synchronization signals in the one or more synchronization signals are located at different frequency positions in the first grid.

20. A computer program product having program code, the computer program product comprising a computer program which, when run on a computer, executes the method according to claims 1 to 19.

21. A processor for performing the method according to any one of claims 1 to 19.

22. A computer-readable storage medium comprising a computer program which, when run on a computer, causes the computer to perform the method according to any one of claims 1 to 19.

23. An apparatus comprising: a memory for storing a computer program; and a processor for calling and running the computer program from the memory to perform the method according to any one of claims 1 to 19.

24. A communication system comprising: an apparatus for performing the method according to any one of claims 1, 3 to 19, and an apparatus for performing the method according to any one of claims 2 to 19.

25. A communication device comprising a unit for performing the method according to any one of claims 1 to 19.

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