Patent Description:
In a Long Term Evolution (Long Term Evolution, LTE) system, there are a fixed uplink carrier and a fixed downlink carrier (the uplink carrier and the downlink carrier may at least partially overlap in frequency domain). A terminal device and a network may perform uplink and downlink communication by using the fixed uplink carrier and downlink carrier respectively. The terminal may perform random access by using the fixed uplink carrier.

A future communications system requires relatively high communication performance.

Therefore, how to improve communication performance in terms of random access is a problem that needs to be resolved urgently. Related technologies are known from the patent publication document <CIT> and <CIT>.

Embodiments of this application provide a wireless communication method and a device, to improve communication performance in terms of random access.

To describe the technical solutions in the embodiments of this application more clearly, the following briefly describes the accompanying drawings required for describing the embodiments or the prior art. Apparently, the accompanying drawings in the following description show merely some embodiments of this application, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.

The technical solutions in the embodiments of this application are described with reference to the accompanying drawings in the embodiments of this application below.

The technical solutions according to the embodiments of this application may be applied to a variety of communications systems, such as a Global System for Mobile communications (Global System for Mobile Communications, "GSM" for short) system, a Code Division Multiple Access (Code Division Multiple Access, "CDMA" for short) system, a Wideband Code Division Multiple Access (Wideband Code Division Multiple Access, "WCDMA" for short) system, a General Packet Radio Service (General Packet Radio Service, "GPRS" for short), a Long Term Evolution (Long Term Evolution, "LTE" for short) system, an LTE Frequency Division Duplex (Frequency Division Duplex, "FDD" for short) system, an LTE Time Division Duplex (Time Division Duplex, "TDD" for short), a Universal Mobile Telecommunications system (Universal Mobile Telecommunications system, "UMTS" for short), a Worldwide Interoperability for Microwave Access (Worldwide Interoperability for Microwave Access, "WiMAX" for short) communications system, a future <NUM> system (which may also be referred to as a New Radio (New Radio, NR) system), or the like.

It should be understood that terms "system" and "network" in this specification are usually interchangeably used in this specification. The term "and/or" in this specification is only an association relationship for describing the associated objects, and represents that three relationships may exist. For example, A and/or B may represent the following three cases: only A exists, both A and B exist, and only B exists.

<FIG> shows a wireless communications system <NUM> according to an embodiment of this application.

It should be understood that <FIG> exemplarily shows one network device and two terminal devices. Optionally, the wireless communications system <NUM> may include a plurality of network devices and another quantity of terminal devices may be included in a coverage area of each network device. This is not limited in this embodiment of this application.

Optionally, the wireless communications system <NUM> may further include another network entity such as a network controller or a mobility management entity. This is not limited in this embodiment of this application.

As shown in <FIG>, the wireless communications system <NUM> may include a network device <NUM>. The network device <NUM> may be a device communicating with a terminal device. The network device <NUM> may provide communication coverage for a specific geographic area, and may communicate with a terminal device (for example, UE) located within the coverage area. Optionally, the network device <NUM> may be a base transceiver station (Base Transceiver Station, BTS) in a GSM system or a CDMA system, may be a NodeB (NodeB, NB) in a WCDMA system, or may be an evolved Node B (Evolved Node B, eNB or eNodeB) in an LTE system or a wireless controller in a cloud radio access network (Cloud Radio Access Network, CRAN), or the network device may be a relay station, an access point, an in-vehicle device, a wearable device, a network-side device in a future <NUM> network, a network device in a future evolved public land mobile network (Public Land Mobile Network, PLMN), or the like.

The wireless communications system <NUM> further includes at least one terminal device <NUM> located within a coverage area of the network device <NUM>. The terminal device <NUM> may be mobile or fixed. Optionally, the terminal device <NUM> may be an access terminal, user equipment (User Equipment, UE), a user unit, a user station, a mobile site, a mobile station, a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a wireless communications device, a user agent, or a user apparatus. The access terminal may be a cellular phone, a cordless phone, a Session Initiation Protocol (Session Initiation Protocol, SIP) phone, a wireless local loop (Wireless Local Loop, WLL) station, a personal digital assistant (Personal Digital Assistant, PDA), a handheld device having a wireless communication function, a computing device or another processing device connected to a wireless modem, an in-vehicle device, a wearable device, a terminal device in a future <NUM> network, a terminal device in a future evolved PLMN, or the like.

Optionally, the terminal device <NUM> may perform device to device (Device to Device, D2D) communication.

Optionally, a <NUM> system or network may be further referred to as a new radio (New Radio, NR) system or network.

A high frequency band is an important alternative frequency band for deploying a <NUM> (NR) network. Because a frequency band is relatively high, a coverage area is relatively limited (as compared with low frequency LTE). In a downlink (Downlink, DL), because a network device has a relatively high transmit power, large-scale multiple input multiple output (Multiple Input Multiple Output, MIMO) (hybrid Beamforming) or the like improves DL coverage. Because a terminal device has a limited transmit power, UL coverage will become the bottleneck.

Therefore, one uplink (Uplink, UL) carrier may be deployed at a low frequency and used to perform NR transmission. The UL carrier may be referred to as a supplementary uplink (Supplementary Uplink, SUL) carrier. In this case, NR has at least two UL carriers. To be specific, one UL carrier is the SUL carrier, and the other UL carrier is a high frequency UL carrier (which may be referred to as an NR dedicated UL (dedicated UL) carrier).

For example, as shown in <FIG>, the NR system may include a high frequency UL carrier that belongs to a frequency band f0 and a low frequency UL carrier that belongs to a frequency band f1.

As shown in <FIG>, frequency division multiplexing (Frequency Division Duplexing, FDD) is performed on the high frequency UL carrier that belongs to the frequency band f0 and a high frequency DL carrier that belongs to the frequency band f0. Alternatively, as shown in <FIG>, time division multiplexing (Time Division Duplexing, TDD) is performed on the high frequency UL carrier that belongs to the frequency band f0 and a high frequency DL carrier that belongs to the frequency band f1.

Optionally, the SUL carrier may further share a spectrum resource with the LTE system. To be specific, in f1, only one or more resources may be used for NR, and the other resources are used for LTE. Resources may be shared in a frequency division multiplexing (Frequency Division Multiplexing, FDM) or a time division multiplexing (Time Division Multiplexing, TDM) manner (for example, a TDM manner shown in <FIG>).

It should be understood that although in the foregoing, an example in which the NR system has two UL carriers is used for description, this embodiment of this application is not limited thereto. For example, the NR system may alternatively have three or more UL carriers.

It should be further understood that in this embodiment of this application, a plurality of UL carriers included in the NR system may all be used by the terminal device to perform uplink transmission. However, during configuration, it may be only configured that the terminal device uses one or more UL carriers to perform uplink transmission.

Optionally, a quantity of UL carriers used by the terminal device and a specific UL carrier that are configured by the network device may change dynamically.

Optionally, after initiating a PRACH preamble, the terminal device monitors (monitor) a random access request (Random Access Request, RAR) of the network device at a corresponding position. The network device uses a random access radio network temporary identity (Random Access Radio Network Temporary Identity, RA-RNTI) to send a random access response. The terminal device uses a same RA-RNTI to receive the random access response.

In the LTE system, the RA-RNTI may be calculated in the following three manners.

In the third manner: <MAT>
where SFN_id is an index of the first radio frame of the specified PRACH resource.

It should be understood that the foregoing manners of acquiring an RA-RNTI are only several implementations. There may be further other implementations in this embodiment of this application.

A manner of acquiring an RA-RNTI in the NR system may be the same as or different from a manner of acquiring an RA-RNTI in the LTE system.

If two terminal devices send a random access request (including a random access code, that is, a random access preamble) respectively on an NR dedicated UL carrier and a SUL carrier, the two terminal devices may receive the same RAR, and a UL carrier on which a preamble that corresponds to the RAR is sent cannot be distinguished.

Therefore, for the foregoing scenario in which there is a plurality of uplink carriers, the embodiments of this application provide the following solutions for random access.

<FIG> is a schematic flowchart of a wireless communication method <NUM> according to an embodiment of this application. The method <NUM> may be optionally applied to the system shown in <FIG>, but is not limited thereto. The method <NUM> includes at least some of the following content.

A terminal device sends a first random access request to a network device on a first uplink carrier.

The network device receives the first random access request sent by the terminal device on the first uplink carrier.

The network device sends a first random access response in response to the first random access request based on the first uplink carrier.

The terminal device acquires, based on the first uplink carrier, the first random access response sent by the network device in response to the first random access request.

Therefore, in this embodiment of this application, a random access response is fed back based on an uplink carrier on which a random access request is sent, so that if there is a plurality of uplink carriers, a source of the random access request corresponding to the random access response can be distinguished when possible.

The network device determines a first random access radio network temporary identity RA-RNTI required to send the first random access response; and sends the first random access response based on the determined first RA-RNTI. Correspondingly, based on the first uplink carrier, the terminal device determines the first RA-RNTI for the first random access response; and acquires the first random access response based on the determined first RA-RNTI. Optionally, the network device further determines at least one of the following based on the first uplink carrier: a resource required to send the first random access response, and information for indicating a random access request source in the first random access response; and sends the first random access response based on the determined at least one. Correspondingly, based on the first uplink carrier, the terminal device determines at least one of the following: the resource occupied by the first random access response, and the information for indicating the random access request source in the first random access response; and acquires the first random access response based on the determined at least one.

Optionally, the network device sends configuration information to the terminal device, where the configuration information is used to indicate at least one of the resource required to send the first random access response, a determining manner or one or more parameters of the first random access radio network temporary identity required to send the first random access response, and the information (that is, information that indicates a random access request source) carried in the first random access response.

It should be understood that the resource required to send the first random access response, the determining manner or one or more parameters of the first random access radio network temporary identity required to send the first random access response, and the information carried in the first random access response may alternatively be preset on the terminal device and do not need to be configured by the network device.

Optionally, in this embodiment of this application, the resource that is determined based on the first uplink carrier and is required to send the first random access response includes: a control resource set CORESET or search space to which a control channel carrying the first random access response belongs.

Optionally, the control resource set (Control Resource Set, CORESET) or search space (Search space) to which the control channel carrying the first random access response belongs is different from a CORESET or search space to which a control channel carrying a second random access response belongs, and the second random access response is a response to a second random access request on a second uplink carrier.

Specifically, after sending a physical random access channel (Physical Random Access Channel, PRACH) preamble (preamble) on a UL carrier, UE needs to monitor (monitor) a random access response (Random Access Response, RAR) of a network. In NR, a control channel (NR-PDCCH) first needs to be detected before a random access response can be received. The network device configures a control channel differently to enable detection of different control channels after preambles are sent on different ULs. Some specific configuration options are as follows:.

In a manner, a CORESET <NUM> or a CORESET group <NUM> (which includes a plurality of CORESETs) is a control channel resource used to receive an RAR corresponding to a preamble sent in an NR dedicated UL, and a CORESET <NUM> or a CORESET group <NUM> (which includes a plurality of CORESETs) includes a control channel resource used to receive an RAR corresponding to a preamble sent in an NR SUL.

In another manner, a search space <NUM> includes a control channel resource used to receive an RAR corresponding to a preamble sent in an NR dedicated UL, and a search space <NUM> includes a control channel resource used to receive an RAR corresponding to a preamble sent in an NR SUL.

Optionally, information carried in a random access request source field of the first random access response is different from information carried in a random access request source field of the second random access response, where the second random access response is the response to the second random access request on the second uplink carrier, and the random access request source field indicates an uplink carrier on which the random access request is located.

Specifically, the network device adds information to a random access response to indicate a UL to which a corresponding random access request belongs. For example, the RAR indicates that the corresponding random access request belongs to an NR dedicated UL or a SUL.

Optionally, the first random access response carries a random access request source field, and the second random access response does not carry a random access request source field, where the second random access response is the response to the second random access request on the second uplink carrier, and the random access request source field indicates an uplink carrier on which the random access request is located is the first uplink carrier.

Specifically, the network device adds information to a random access response to indicate a UL to which a corresponding random access request belongs. For example, the RAR does not indicate a UL to which a corresponding random access request belongs, the random access request correspondingly belongs to a default UL (for example, an NR dedicated UL). If the RAR indicates a UL, the random access request belongs to the indicated UL (for example, a SUL).

Optionally, in this embodiment of this application, the first uplink carrier and the second uplink carrier described above belong to different frequency bands. For example, the first uplink carrier is the SUL carrier described in <FIG>, and the second uplink carrier is the dedicated UL carrier described in <FIG>.

A calculation formula of the first RA-RNTI is different from a calculation formula of a second RA-RNTI, or one or more parameters in a calculation formula of the first RA-RNTI are different from one or more parameters in a calculation formula of a second RA-RNTI, where the second RA-RNTI is an RA-RNTI required for the second random access response to the second random access request on the second uplink carrier.

Specifically, after sending a PRACH preamble on a UL carrier, UE needs to monitor (monitor) a random access response RAR of a network. In NR, a control channel (NR-PDCCH) first needs to be detected before a random access response can be received. Transmission on a control channel is scrambled by using an RA-RNTI. Different RA-RNTIs may distinguish RARs corresponding to different preambles. If a SUL is supported for random access, compared with a dedicated UL carrier, an extra factor is introduced into a formula of an RA-RNTI. The factor is associated with the SUL. In this way, it can be avoided that preambles on two ULs correspond to a same RA-RNTI. For example, if there is no SUL, the value range of an RA-RNTI is [x, y] (y > x ≥ <NUM>). For a preamble transmitted in a SUL, a factor Z (Z > y) is added based on the foregoing technology to calculate an RA-RNTI, so that it can be avoided that two ULs correspond to a same RA-RNTI.

For example, for a dedicated UL carrier, the formula for calculating an RA-RNTI may be the foregoing Formula <NUM>, Formula <NUM> or Formula <NUM>, and Z may be added to Formula <NUM>, Formula <NUM>, and Formula <NUM> respectively to obtain formulas for calculation for a SUL carrier.

Certainly no covered by the claimed invention, Z may be not greater than y. In this case, instead of being completely avoided, a same RA-RNTI is less likely to occur.

<FIG> is a schematic flowchart of a wireless communication method <NUM> according to an embodiment of this application not covered by the claimed invention. The method <NUM> includes at least some of the following content.

A network device determines configuration information during random access for each of a plurality of uplink carriers.

Optionally, the plurality of uplink carriers belongs to different frequency bands respectively.

The network device sends the configuration information for each uplink carrier to a terminal device.

The terminal device receives the configuration information during random access configured by the network device for each of the plurality of uplink carriers.

Perform random access on at least one uplink carrier of the plurality of uplink carriers based on the configuration information.

Therefore, the network device configures the configuration information during random access for each of the plurality of uplink carriers for the terminal device, so that during random access, the terminal device can use the configuration information corresponding to each uplink carrier to perform random access.

Optionally, the configuration information includes a time domain resource and/or a frequency domain resource used to send a random access request on each uplink carrier, where RA-RNTIs corresponding to time domain resources and/or frequency domain resources used to send a random access request on different uplink carriers are at least partially different.

Specifically, when configuring random access channel (Random Access Channel, RACH) resources correspond to different ULs, the network device coordinates a time and frequency resource and/or a frequency domain resource of a RACH, thereby avoiding that RA-RNTIs corresponding to preambles on two UL carriers conflict or reduce a probability that RA-RNTIs corresponding to the preambles conflict.

Optionally, at least one of the following configuration information during random access determined respectively for different uplink carriers is different:.

Optionally, the resource required to send the random access response includes: a control resource set CORESET or search space to which a control channel carrying the random access response belongs.

Optionally, control channels of random access responses corresponding to random access requests on different uplink carriers belong to different CORESETs or search spaces.

Optionally, RA-RNTIs for random access responses corresponding to random access requests on different uplink carriers have different calculation formulas or one or more different parameters in a calculation formula.

Optionally, the configuration information includes a configuration for the following: an indication of a random access request source in a random access response corresponding to a random access request transmitted on each uplink carrier.

Optionally, random access request source fields of random access responses corresponding to random access requests on different uplink carriers carry different information, where the random access request source field indicates an uplink carrier on which the random access request is located.

Optionally, the plurality of uplink carriers includes a first uplink carrier and a second uplink carrier, a first random access response carries a random access request source field, and a second random access response does not carry a random access request source field, where the first random access response is a response to a first random access request on the first uplink carrier, the second random access response is a response to a second random access request on the second uplink carrier, and the random access request source field indicates an uplink carrier on which the random access request is located is the first uplink carrier.

It should be understood that for the descriptions of the method <NUM> and the method <NUM>, reference may be made to each other, and the method <NUM> and the method <NUM> may be used in combination. For brevity, details are not described herein again.

<FIG> is a schematic block diagram of a network device <NUM> according to an embodiment of this application. As shown in <FIG>, the network device <NUM> includes a receiving unit <NUM> and a sending unit <NUM>.

The receiving unit <NUM> is configured to receive a first random access request sent by a terminal device on a first uplink carrier. The sending unit <NUM> is configured to send a first random access response in response to the first random access request based on the first uplink carrier.

It should be understood that the network device <NUM> may perform corresponding operations performed by the network device in the foregoing method <NUM>. For brevity, details are not described herein again.

<FIG> is a schematic block diagram of a network device <NUM> according to an embodiment of this application not covered by the claimed invention. As shown in <FIG>, the network device <NUM> includes a processing unit <NUM> and a communications unit <NUM>.

The processing unit <NUM> is configured to determine configuration information during random access for each of a plurality of uplink carriers.

The communications unit <NUM> is configured to send the configuration information for each uplink carrier to a terminal device.

<FIG> is a schematic block diagram of a terminal device <NUM> according to an embodiment of this application. As shown in <FIG>, the terminal device <NUM> includes a sending unit <NUM> and a receiving unit <NUM>.

The sending unit <NUM> is configured to send a first random access request to a network device on a first uplink carrier. The receiving unit <NUM> is configured to acquire, based on the first uplink carrier, a first random access response sent by the network device in response to the first random access request.

It should be understood that the terminal device <NUM> may perform corresponding operations performed by the terminal device in the foregoing method <NUM>. For brevity, details are not described herein again.

<FIG> is a schematic block diagram of a terminal device <NUM> according to an embodiment of this application not covered by the claimed invention. As shown in <FIG>, the terminal device <NUM> includes a receiving unit <NUM> and an access unit <NUM>.

The receiving unit <NUM> is configured to receive configuration information during random access configured by a network device for each of a plurality of uplink carriers. The access unit <NUM> is configured to perform random access on at least one uplink carrier of the plurality of uplink carriers based on the configuration information.

<FIG> is a schematic structural diagram of a system chip <NUM> according to an embodiment of this application. The system chip <NUM> in <FIG> includes an input interface <NUM>, an output interface <NUM>, a processor <NUM>, and a memory <NUM> that may be connected through an internal communication connection line, where the processor <NUM> is configured to execute code in the memory <NUM>.

Optionally, when the code is executed, the processor <NUM> implements the method performed by a network device in the method embodiment. For brevity, details are not described herein again.

Optionally, when the code is executed, the processor <NUM> implements the method performed by a terminal device in the method embodiment. For brevity, details are not described herein again.

<FIG> is a schematic block diagram of a communications device <NUM> according to an embodiment of this application. As shown in <FIG>, the communications device <NUM> includes a processor <NUM> and a memory <NUM>. The memory <NUM> may store program code, and the processor <NUM> may execute the program code stored in the memory <NUM>.

Optionally, as shown in <FIG>, the communications device <NUM> may include a transceiver <NUM>, and the processor <NUM> may control the transceiver <NUM> to communicate externally.

Optionally, the processor <NUM> may invoke the program code stored in the memory <NUM> to perform corresponding operations of a network device in the method embodiment. For brevity, details are not described herein again.

Optionally, the processor <NUM> may invoke the program code stored in the memory <NUM> to perform corresponding operations of a terminal device in the method embodiment. For brevity, details are not described herein again.

It should be understood that the processor in the embodiments of this application may be an integrated circuit chip and has a signal processing capability. During implementation, the steps in the foregoing method embodiment may be implemented by using an integrated logic circuit of hardware in the processor or an instruction in the form of software. The processor may be a general-purpose processor, a digital signal processor (Digital Signal Processor, DSP), an application-specific integrated circuit (Application-Specific Integrated Circuit, ASIC), a field programmable gate array (Field Programmable Gate Array, FPGA) or another programmable logic device, a discrete gate or a transistor logic device, or a discrete hardware component. The methods, steps, and logic block diagrams disclosed in the embodiments of this application may be implemented or performed. The general-purpose processor may be a microprocessor or the processor may alternatively be any conventional processor or the like. The steps in the methods disclosed with reference to the embodiments of this application may be directly performed or completed by a decoding processor embodied as hardware or performed or completed by using a combination of hardware and software modules in a decoding processor. The software module may be located at a random-access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register or another mature storage medium in this field. The storage medium is located at a memory, and the processor reads information in the memory and completes the steps in the foregoing methods in combination with the hardware thereof.

It may be understood that the memory in the embodiments of this application may be a volatile memory or a non-volatile memory, or may include both a volatile memory and a non-volatile memory. The non-volatile memory may be a read-only memory (Read-Only Memory, ROM), a programmable read-only memory (Programmable ROM, PROM), an erasable programmable read-only memory (Erasable PROM, EPROM), an electrically erasable programmable read-only memory (Electrically EPROM, EEPROM) or a flash memory. The volatile memory may be a random-access memory (Random-access memory, RAM) and is used as an external cache. For exemplary rather than limitative description, many forms of RAMs can be used, for example, a static random-access memory (Static RAM, SRAM), a dynamic random-access memory (Dynamic RAM, DRAM), a synchronous dynamic random-access memory (Synchronous DRAM, SDRAM), a double data rate synchronous dynamic random-access memory (Double Data Rate SDRAM, DDR SDRAM), an enhanced synchronous dynamic random-access memory (Enhanced SDRAM, ESDRAM), a synchronous link dynamic random-access memory (Synchlink DRAM, SLDRAM), and a direct Rambus random-access memory (Direct Rambus RAM, DR RAM). It should be noted that the memories in the systems and methods described herein are intended to include, but are not limited to, these memories and memories of any other suitable type.

A person of ordinary skill in the art may be aware that, in combination with the examples described in the embodiments disclosed in this specification, units and algorithm steps may be implemented by electronic hardware, or a combination of computer software and electronic hardware.

It may be clearly understood by a person skilled in the art that, for the purpose of convenient and brief description, for a detailed working process of the foregoing system, apparatus, and unit, refer to a corresponding process in the foregoing method embodiment, and details are not described herein again.

For example, the described apparatus embodiment is merely exemplary. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections may be implemented through some interfaces. The indirect couplings or communication connections between the apparatuses or units may be implemented in electrical, mechanical or other forms.

When the functions are implemented in a form of a software functional unit and sold or used as an independent product, the functions may be stored in a computer-readable storage medium. Based on such an understanding, the technical solutions of this application essentially, or the part contributing to the prior art, or part of the technical solutions may be implemented in the form of a software product. The computer software product is stored in a storage medium, and includes several instructions for instructing a computer device (which may be a personal computer, a server, a network device, or the like) to perform all or some of the steps of the method described in the embodiments of this application. The foregoing storage medium includes: any medium that can store program code, such as a USB flash disk, a removable hard disk, a read-only memory ( Read-Only Memory, ROM), a random-access memory (Random-access memory, RAM), a magnetic disk, or an optical disk.

Claim 1:
A wireless communication method, comprising:
sending (<NUM>), by a terminal device, a random access request to a network device on a high frequency uplink carrier or a supplementary uplink, SUL, carrier deployed at a frequency band lower than the high frequency uplink carrier; and
acquiring (<NUM>), by the terminal device, a random access response, RAR, sent by the network device in response to the random access request,
wherein the acquiring (<NUM>), by the terminal device, of the RAR sent by the network device in response to the random access request comprises:
acquiring the RAR based on a random access radio network temporary identity, RA-RNTI, for the RAR, characterized in that a first RA-RNTI for the RAR of the SUL carrier is determined based on a calculation formula formed by adding, based on another calculation formula of a second RA-RNTI for the RAR of the high frequency uplink carrier, one factor associated with the SUL carrier, and
wherein,
when the random access request is sent on the high frequency uplink carrier, a value range of the first RA-RNTI is [x, y], where y > x≥<NUM>;
when the random access request is sent on the SUL carrier, a value range of the second RA-RNTI is [x+Z, y+Z], where Z is the factor associated with the SUL carrier and greater than any value in a range from x to y.