Communication method and device

Abstract

An embodiment of the present application provides a communication method and device that can be applied to the field of communication technology supporting terminal devices with reduced capability, such as low-capability UEs or MTC UEs. The method includes: a first network device determines that the type of the first terminal device is a first type, the first network device sends a handover request message, the handover request message includes first indication information, and the first indication information includes identification information of the first type; the first network device receives a handover confirmation message or a handover preparation failure message. Through the above process, it is possible to avoid switching the first type of terminal device to a network device that does not support the first type.

Description

[0001] This application claims priority to PCT application number PCT / CN2020 / 077500, filed on March 2, 2020, entitled “Communication Methods and Apparatus,” the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0003] "Support of reduced capability NR devices" is one of the new research areas proposed by the 3rd Generation Partnership Project (3GPP) in Release 17. "Support of reduced capability NR devices" is a function that supports scenarios with narrower bandwidth and lower peak data rates, mainly providing lightweight communications for high-end machine type communication (MTC) devices. Terminal devices with weaker capabilities suitable for this scenario can be called reduced capability UEs or low-capability UEs. Compared with traditional UEs, reduced capability UEs generally support bandwidths below 20MHz, peak data rates of 5-10Mb / s, and have lower requirements for performance such as latency and reliability. This type of device mainly includes: wearable devices, surveillance cameras, industrial sensors, etc.

[0004] In the current new radio (NR) protocol, the UE reports its supported uplink and downlink bandwidths through a 10-bit bitmap. The 10 bits correspond to whether the UE supports bandwidths of 5MHz, 10MHz, 15MHz, 20MHz, 25MHz, 30MHz, 40MHz, 50MHz, 60MHz, and 80MHz. According to current protocol requirements, all UEs must support 100MHz bandwidth. Therefore, even though there is no bit indicating whether the UE supports 100MHz bandwidth in the bitmap reported by the UE, legacy network devices assume that the UE supports 100MHz bandwidth. In other words, legacy network devices believe that the bandwidth supported by the UE is the bandwidth reported by the UE in the bitmap and 100MHz.

[0005] For reduced performance UEs, they cannot support 100 MHz and only support the bandwidth reported in the bit map. Therefore, if a reduced performance UE operates in a cell with network equipment using the current protocol, that is, a legacy network equipment, the network equipment may misjudge the reduced performance UE's capabilities, such as assigning a BWP that is not within its supported bandwidth range, which may cause the reduced performance UE to not function properly. Summary of the Invention

[0006] Embodiments of the present application provide a communication method and device that can prevent a UE with reduced performance from residing in a legacy network device, or prevent a UE with reduced performance from switching to a legacy network device.

[0007] In a first aspect, an embodiment of the present application provides a communication method, which includes: a first network device determines that the type of a first terminal device is a first type, the first network device sends a switching request message, the switching request message includes first indication information, and the first indication information includes identification information of the first type; the first network device receives a switching confirmation message or a switching preparation failure message.

[0008] In the above solution, the first network device includes first indication information in the handover request message, and the first indication information includes the identification information of the first type. Thus, after receiving the handover request message, if the second network device does not support the first type of terminal device, it sends a handover preparation failure message to the first network device. If the second network device supports the first type of terminal device, it continues according to the existing handover process and sends a handover confirmation message to the first network device when it finally confirms that the handover is approved. This process can prevent the handover of the first type of terminal device to a network device that does not support the first type.

[0009] The present application involves multiple types of terminal devices, and the first type is one of the multiple types. In one example, the multiple types of terminal devices can be divided according to the capabilities of the terminal devices. Optionally, the multiple types of terminal devices may include a first type and a second type. The capabilities of the first type of terminal devices are lower than those of the second type of terminal devices. Exemplarily, the first type of terminal device may be a reduced performance UE, and the second type of terminal device may be a terminal device with capabilities higher than the reduced performance UE, for example, the second type of terminal device may be a legacy UE.

[0010] The first type of identification information refers to any information that can be used to identify the first type. In one example, the first type of identification information can be the name of the first type. In another example, different types can correspond to different indexes, so the first type of identification information can be the index corresponding to the first type.

[0011] In a possible implementation, the first indication information further includes key value indication information, where the key value indication information is used to instruct the second network device to reject the switching under the first condition.

[0012] Optionally, the first condition may be that the second network device does not support the first type of terminal device. "Not supported" here may include two situations. The first situation is that the second network device can recognize the first type of identification information, but the second network device does not support the first type of terminal device. The second situation is that the second network device cannot recognize the first type of identification information.

[0013] In one example, the handover request message includes a new IE or field. For example, the name of the new IE or field is reduced capability UE. The IE or field serves as the first indication information. The IE or field includes first-type identification information and key value indication information. For example, the name of the IE or field is the first-type identification information, and the key value of the IE or field can be "reject" or "ignore", that is, key value indication information, indicating whether the second network device adopts a rejection action or an ignore action when it cannot recognize the IE or field or cannot recognize the identification information carried by the IE or field.

[0014] For the switching scenario, assuming that the first terminal device to be switched is a reduced performance UE, the first network device sets the key value of the IE or field to "reject" when generating a switching request message. In this way, after the second network device receives the switching request message, if the second network device cannot recognize the IE or field, the second network device rejects the switching behavior and sends a switching failure message to the first network device. If the second network device can recognize the IE or field, the second network device can continue to execute according to the existing switching process, and when it is finally determined to agree to the switching, it sends a switching confirmation message to the first network device. Therefore, it can effectively prevent the first network device from switching the reduced performance UE to the legacy network device.

[0015] Optionally, the first network device may further provide services for a second terminal device, where the second terminal device is a second type of terminal device (eg, a legacy UE). That is, the first network device may further support the second type of terminal device.

[0016] In one possible implementation, the first network device receives a switching confirmation message or a switching preparation failure message, including: the first network device receives a switching confirmation message from a second network device, and the second network device supports the first type of terminal device; or the first network device receives a first switching preparation failure message from the second network device, the first switching preparation failure message includes failure information corresponding to the first type, and the second network device does not support the first type of terminal device.

[0017] In one example, the failure cause value carried in the first handover preparation failure message indicates that the handover failure is caused by not supporting the first type.

[0018] In one possible implementation, the first network device sends a switching request message, including: the first network device sends the switching request message to the second network device; or, the first network device sends the switching request message to the second network device through the access and mobility management function AMF device.

[0019] For example, when an Xn interface connection is established between the first network device and the second network device, the first network device sends the handover request message to the second network device. When an Xn interface connection is not established between the first network device and the second network device, the first network device and the second network device perform a handover process through the NG interface, that is, the first network device sends the handover request message to the second network device through the AMF device.

[0020] In a handover scenario based on the NG interface, the first network device sends a handover request message to the AMF, and includes the first indication information (such as the above-mentioned new IE or field) in the handover request message. Exemplarily, the first indication information can be added to the fifth indication information that can be transparently transmitted to the AMF. The fifth indication information can be, for example, the Handover Required Transfer IE. Since the fifth indication information is a transparent IE for the AMF, the AMF does not interpret the fifth indication information, but directly includes it in the handover request message and sends it to the second network device. The second network device interprets all the contents contained in the fifth indication information. If the second network device can recognize the first indication information (for example, it can recognize the above-mentioned new IE / field, or can recognize the identification information carried by the new IE / field), it will proceed according to the existing protocol, and when it is finally determined to agree to the handover, it will send a handover confirmation message to the AMF, and the AMF will send a handover command message to the first network device. If the second network device cannot recognize the first indication information (for example, cannot recognize the above-mentioned new IE / field, or cannot recognize the identification information carried by the new IE / field), the second network device rejects the switching behavior and sends a switching failure message to the AMF, and the AMF sends a switching preparation failure message to the first network device.

[0021] In a second aspect, an embodiment of the present application provides a communication method, which includes: a second network device receives a switching request message, the switching request message includes first indication information, the first indication information contains first type of identification information, the first type is the first type of the terminal device; or the first type is the type of the first terminal device; the second network device sends a switching confirmation message or a switching preparation failure message.

[0022] In the above solution, since the handover request message includes the first indication information, the first indication information includes the first type of identification information. Thus, after receiving the handover request message, if the second network device does not support the first type of terminal device, it sends a handover preparation failure message to the first network device. If the second network device supports the first type of terminal device, it continues according to the existing handover process and sends a handover confirmation message to the first network device when it finally confirms that the handover is approved. This process can prevent the handover of the first type of terminal device to a network device that does not support the first type.

[0023] In a possible implementation, the switching request message further includes capability information of the first terminal device, and the type of the first terminal device is the first type.

[0024] The capability information may include one or more of the following: maximum transmission bandwidth, transmission rate, reliability, delay tolerance, number of antennas, or battery life, etc.

[0025] In a possible implementation, the first indication information further includes key value indication information, where the key value indication information is used to instruct the second network device to reject the switching under the first condition.

[0026] In one possible implementation, the second network device receives the switching request message, including: the second network device receives the switching request message sent by the first network device; or, the second network device receives the switching request message from the first network device through the access and mobility management function AMF device.

[0027] In a third aspect, an embodiment of the present application provides a communication method, including: a network device generates a system message, the system message includes second indication information, the second indication information is used to indicate a first type, the first type is the first type of the terminal device; the network device sends the system message.

[0028] In the application scenario of the above solution, the network device may be a "network device supporting reduced performance UE".

[0029] The second indication information is used to indicate the first type. For example, the first type of terminal device may be a reduced performance UE.

[0030] In a possible implementation, the system message is a system message block SIB1, and the second indication information is included in SIB1.

[0031] In one possible implementation, the second indication information is used to indicate that the cell of the network device allows the first type of terminal device to reside. The presence or inclusion of the second indication information in the system message generated by the network device indicates that the cell of the network device allows the first type of terminal device to reside. The absence or inclusion of the second indication information in the system message generated by the network device indicates that the cell of the network device does not allow the first type of terminal device to reside.

[0032] In one possible implementation, the second indication information is used to indicate whether the cell of the network device allows the first type of terminal device to reside. The second indication information exists / includes in the system message generated by the network device, and the value of the second indication information is a first preset value, indicating that the cell of the network device allows the first type of terminal device to reside. The second indication information exists / includes in the system message generated by the network device, and the value of the second indication information is a second preset value, indicating that the cell of the network device does not allow the first type of terminal device to reside. The second indication information does not exist / does not include in the system message generated by the network device, indicating that the cell of the network device does not allow the first type of terminal device to reside.

[0033] In the above solution, by including second indication information in the system message, the second indication information indicates whether the cell of the network device allows or does not allow the first type of terminal device to reside. In this way, the terminal device can determine whether it is allowed to reside in the cell of the network device based on the second indication information in the system message. For a reduced performance UE, if it is determined based on the received system message that the network device does not allow the reduced performance UE to reside, it will not reside in the cell of the network device. Only when it is determined that the network device allows the reduced performance UE to reside, will the cell of the network device be selected as a candidate for cell selection, thereby preventing the reduced performance UE from residing in a legacy network device.

[0034] In a possible implementation, the second indication information may also be used to indicate whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection.

[0035] Optionally, the network device uses the second indication information present / included in the system message to indicate that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection.

[0036] Optionally, when the system message contains / includes second indication information indicating that the network device allows the first type of terminal device to reside, the value of the second indication information can be used to indicate whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection. The value of the second indication information is a first preset value, indicating that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection, and the value of the second indication information is a second preset value, indicating that the cell of the network device does not allow the first type of terminal device to perform intra-frequency reselection.

[0037] Optionally, the second indication information and the sixth indication information may be used to indicate whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection. The sixth indication information may be indication information used to indicate whether the cell of the network device allows the terminal device (here, the terminal device may be a legacy UE) to perform intra-frequency reselection.

[0038] The sixth indication information and the second indication information may be included in the same system message or in different system messages.

[0039] In the case where the second indication information exists / is included in the system message, if the sixth indication information indicates that the cell of the network device allows the terminal device (here the terminal device may be a legacy UE) to perform intra-frequency reselection, it means that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection; if the sixth indication information indicates that the cell of the network device does not allow the terminal device (here the terminal device may be a legacy UE) to perform intra-frequency reselection, it means that the cell of the network device does not allow the first type of terminal device to perform intra-frequency reselection. In the case where the second indication information does not exist / is not included in the system message, it means that the cell of the network device does not allow the first type of terminal device to perform intra-frequency reselection, and the value of the sixth indication information does not need to be considered at this time.

[0040] In the above solution, the second indication information is also used to indicate whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection. In this way, the terminal device determines whether intra-frequency reselection is allowed based on the second indication information. For a reduced performance UE, if it is determined based on the received system information that the network device does not allow the reduced performance UE to perform intra-frequency reselection, intra-frequency reselection will not be performed. Only if it is determined that the network device allows the reduced performance UE to perform intra-frequency reselection, intra-frequency reselection will be considered, thereby preventing the reduced performance UE from reselecting to a legacy network device.

[0041] In a fourth aspect, an embodiment of the present application provides a communication method, which includes: a first terminal device receives a system message from a network device; the first terminal device obtains second indication information from the system message, and the second indication information is used to indicate a first type, and the first type is the first type of the terminal device.

[0042] The first terminal device may be a terminal device of the first type, for example, a reduced performance UE. The "obtaining" in "the first terminal device obtaining the second indication information from the system message" refers to an action of the first terminal device obtaining the second indication information from the system message. The result of the obtaining may include: obtaining the second indication information or failing to obtain the second indication information.

[0043] In a possible implementation, the system message is a system message block SIB1.

[0044] In one possible implementation, the first terminal device determines whether the first terminal device is allowed to reside in the cell of the network device based on whether the second indication information is obtained from the system message (or based on whether the second indication information exists / included in the system message).

[0045] Optionally, the first terminal device obtains the second indication information from the system message (or the system message contains / includes the second indication information), and determines that the first terminal device is allowed to reside in the cell of the network device; or, the first terminal device cannot obtain the second indication information from the system message (or the system message does not contain / includes the second indication information), and determines that the first terminal device is not allowed to reside in the cell of the network device.

[0046] In one possible implementation, the first terminal device obtains second indication information from a system message (or the system message contains / includes the second indication information), indicating that the network device is a "network device supporting reduced performance UEs." In this case, the first terminal device determines whether to allow camping on the cell of the network device based on the second indication information obtained from the system message.

[0047] Optionally, if the second indication information indicates that the cell of the network device allows the first type of terminal device to reside, the first terminal device determines that the first terminal device is allowed to reside in the cell of the network device; if the second indication information indicates that the cell of the network device does not allow the first type of terminal device to reside, the first terminal device determines that the first terminal device is not allowed to reside in the cell of the network device.

[0048] The first terminal device cannot obtain the second indication information from the system message (or the system message does not contain / does not include the second indication information), indicating that the network device is a legacy network device. In this case, the first terminal device determines that the first terminal device is not allowed to reside in the cell of the network device.

[0049] In a possible implementation, the first terminal device may also determine whether same-frequency reselection is allowed based on the second indication information.

[0050] Optionally, the first terminal device determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection based on the presence / inclusion of the second indication information in the system message. In other words, the first terminal device determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection based on the second indication information obtained from the system message.

[0051] The first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection based on the absence / inclusion of the second indication information in the system message. In other words, the first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection based on the failure to obtain the second indication information from the system message.

[0052] Optionally, when the first terminal device obtains the second indication information from the system message, if the second indication information indicates that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection (for example, the value of the second indication information is a first preset value), the first terminal device determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection. If the second indication information indicates that the cell of the network device does not allow the first type of terminal device to perform intra-frequency reselection (for example, the value of the second indication information is a second preset value), the first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection.

[0053] Optionally, the first terminal device may further receive sixth indication information from the network device. When the system message contains / includes the second indication information (or the first terminal device obtains the second indication information from the system message), the first terminal device determines, based on the sixth indication information, whether the cell of the network device allows the first terminal device to perform intra-frequency reselection.

[0054] The sixth indication information and the second indication information may be included in the same system message or in different system messages.

[0055] The system message contains / includes the second indication information (or the first terminal device obtains the second indication information from the system message), that is, the network device is a "network device that supports reduced performance UE", and the sixth indication information indicates that the cell of the network device allows the terminal device (the terminal device here can be a legacy UE) to perform intra-frequency reselection, and the first terminal device determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection.

[0056] The system message contains / includes the second indication information (or the first terminal device obtains the second indication information from the system message), and the sixth indication information indicates that the cell of the network device does not allow the terminal device (the terminal device here can be a legacy UE) to perform intra-frequency reselection. The first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection.

[0057] The second indication information does not exist / is not included in the system message (or the first terminal device cannot obtain the second indication information from the system message), that is, the network device is a legacy network device, and the first terminal device determines that the cell of the network device does not allow the first terminal device to reselect the same frequency.

[0058] In one possible implementation, the system message further includes: frequency band information and bandwidth information supported by the network device; the first terminal device determines whether to allow camping in the cell of the network device based on whether the second indication information is obtained from the system message and the frequency band information and bandwidth information supported by the network device; or,

[0059] The first terminal device determines whether it is allowed to reside in the cell of the network device based on the second indication information and the frequency band information and bandwidth information supported by the network device.

[0060] In each of the above implementations, by including second indication information in the system message, the second indication information indicates whether the cell of the network device allows or does not allow the first type of terminal device to reside. In this way, the terminal device can determine whether it is allowed to reside in the cell of the network device based on the second indication information in the system message. For a reduced performance UE, if it is determined based on the received system message that the network device does not allow the reduced performance UE to reside, the terminal device will not reside in the cell of the network device. Only when it is determined that the network device allows the reduced performance UE to reside, the cell of the network device is selected as a candidate for cell selection, thereby preventing the reduced performance UE from residing in a legacy network device.

[0061] In each of the above implementations, the second indication information is further used to indicate whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection. In this way, the terminal device determines whether intra-frequency reselection is allowed based on the second indication information. For a reduced performance UE, if it is determined based on the received system information that the network device does not allow the reduced performance UE to perform intra-frequency reselection, intra-frequency reselection is not performed. Intra-frequency reselection is only considered if it is determined that the network device allows the reduced performance UE to perform intra-frequency reselection, thereby preventing the reduced performance UE from reselecting to a legacy network device.

[0062] In one possible implementation, the network device is a network device corresponding to a neighboring cell of a serving cell of the first terminal device; the method further includes: the first terminal device sending the second indication information to the network device corresponding to the serving cell. Alternatively, the first terminal device sends a determination result corresponding to the second indication information to the second network device. The determination result is a result obtained by the first terminal device determining, based on the second indication information, whether the first network device supports the first type of terminal device.

[0063] Optionally, the first terminal device carries the second indication information or the determination result corresponding to the second indication information in a CGI procedure report or a measurement report and sends it.

[0064] In one example, a first terminal device sends the detected PCI of a first cell to a second network device. If the second network device finds that the PCI of the first cell reported by the first terminal device is unrecognizable, it instructs the first terminal device to obtain the neighboring cell information corresponding to the PCI. The first terminal device receives the SIB1 of the first cell and generates a CGI procedure report based on the neighboring cell information parsed from the SIB1. The first terminal device sends the CGI procedure report to the second network device.

[0065] In the above example, the CGI procedure report includes one or more of the following: a PLMN list, a RANAC, a TAC, a cell ID, a frequency band list, and the second indication information. By adding the second indication information in SIB1 to the CGI procedure report, delays caused by measuring or reading information related to other neighboring cells are avoided.

[0066] In the above example, when the second network device initiates a handover, it uses information obtained from the CGI procedure report, including information about whether other network devices support or support reduced-performance UEs, as a criterion to select a target network device. This prevents the reduced-performance UE from being handed over to a legacy network device.

[0067] In a fifth aspect, an embodiment of the present application provides a communication method, which includes: a first terminal device generates capability information, the capability information includes third indication information, and the third indication information is used to indicate the type of the first terminal device, the type of the first terminal device is the first type or the second type; the first terminal device sends the capability information to a network device.

[0068] In a possible implementation, before the first terminal device generates the capability information, the method further includes: the first terminal device receiving a capability request message from the network device.

[0069] In the above implementation, the first terminal device includes the third indication information in the capability information to indicate the type of the first terminal device, so that the network device can determine the type of the first terminal device based on the received capability information. Thus, the network device can adopt different processing methods according to the type of the first terminal device. For example, if the type of the first terminal device is the first type (reduced performance UE), it is considered that the bandwidth supported by the first terminal device is the bandwidth reported by it through bitmap or other forms, and when the first terminal device needs to switch, the first terminal device is switched to the network device that supports reduced performance UE. If the type of the first terminal device is the second type (for example, legacy UE), it is considered that the bandwidth of the first terminal device is the bandwidth reported by it through bitmap or other forms and 100MHz.

[0070] In a sixth aspect, an embodiment of the present application provides a communication method, which includes: a network device receives capability information from a first terminal device, the capability information including third indication information; the network device determines whether the type of the first terminal device is the first type or the second type based on the third indication information.

[0071] In a possible implementation, before the network device receives the capability information from the first terminal device, the method further includes: sending a capability request message to the first terminal device.

[0072] In the above implementation, the first terminal device includes the third indication information in the capability information to indicate the type of the first terminal device, so that the network device can determine the type of the first terminal device based on the received capability information. Thus, the network device can adopt different processing methods according to the type of the first terminal device. For example, if the type of the first terminal device is the first type (reduced performance UE), it is considered that the bandwidth supported by the first terminal device is the bandwidth reported by it through bitmap or other forms, and when the first terminal device needs to switch, the first terminal device is switched to the network device that supports reduced performance UE. If the type of the first terminal device is the second type (for example, legacy UE), it is considered that the bandwidth of the first terminal device is the bandwidth reported by it through bitmap or other forms and 100MHz.

[0073] In the seventh aspect, an embodiment of the present application provides a communication method, which includes: a first network device sends an Xn interface establishment request message to a second network device, wherein the Xn interface establishment request message includes inquiry information, and the inquiry information is used to inquire whether the second network device supports the first type of terminal device; the first network device receives an Xn interface establishment response message or an Xn interface establishment failure message from the second network device; wherein the Xn interface establishment response message includes fourth indication information, and the fourth indication information is used to indicate whether the second network device supports the first type of terminal device.

[0074] In an eighth aspect, an embodiment of the present application provides a communication method, the method comprising: a second network device receives an Xn interface establishment request message from a first network device, the Xn interface establishment request message including inquiry information, the inquiry information being used to inquire whether the second network device supports a first type of terminal device; the second network device sends an Xn interface establishment response message or an Xn interface establishment failure message to the first network device; wherein the Xn interface establishment response message includes fourth indication information, the fourth indication information being used to indicate whether the second network device supports the first type of terminal device.

[0075] In this solution, by including the fourth indication information in the Xn interface establishment response message, the first network device can determine whether the second network device supports the first type of terminal device based on the fourth indication information. The first network device may also store the fourth indication information. When the first network device needs to initiate a handover for the first type of terminal device, it can determine the target network device to handover the first type of terminal device to based on the stored fourth indication information of each network device. This prevents the first type of terminal device from being handed over to a network device that does not support the first type.

[0076] In a ninth aspect, an embodiment of the present application provides a communication device, which may be a first network device or a component within the first network device, such as a chip or an integrated circuit. The communication device may include: a processing unit, a sending unit, and a receiving unit. The processing unit is configured to determine that the type of the first terminal device is a first type; the sending unit is configured to send a handover request message, wherein the handover request message includes first indication information, wherein the first indication information includes identification information of the first type; and the receiving unit is configured to receive a handover confirmation message or a handover preparation failure message.

[0077] In a possible implementation manner, the first indication information further includes key value indication information, where the key value indication information is used to instruct the second network device to reject the switching under the first condition.

[0078] In one possible implementation, the receiving unit is specifically used to: receive a switching confirmation message from a second network device, which supports the first type of terminal device; or receive a first switching preparation failure message from the second network device, which includes failure information corresponding to the first type, and the second network device does not support the first type of terminal device.

[0079] In one possible implementation, the sending unit is specifically used to: send the switching request message to the second network device; or, send the switching request message to the second network device through the access and mobility management function AMF device.

[0080] In a tenth aspect, an embodiment of the present application provides a communication device that can serve as a second network device. The communication device may include: a receiving unit and a sending unit. The receiving unit is configured to receive a handover request message, wherein the handover request message includes first indication information, wherein the first indication information includes identification information of a first type, wherein the first type is a first type of a terminal device; or the first type is a type of a first terminal device; and the sending unit is configured to send a handover confirmation message or a handover preparation failure message.

[0081] In a possible implementation, the switching request message further includes capability information of the first terminal device, and the type of the first terminal device is the first type.

[0082] In a possible implementation, the first indication information further includes key value indication information, where the key value indication information is used to instruct the second network device to reject the switching under the first condition.

[0083] In one possible implementation, the receiving unit is specifically used to: receive a switching request message sent by the first network device; or, receive a switching request message from the first network device through an access and mobility management function AMF device.

[0084] In an eleventh aspect, an embodiment of the present application provides a communication device, which may include: a processing unit and a sending unit. The processing unit is configured to generate a system message, the system message including second indication information, the second indication information being configured to indicate a first type, where the first type is a first type of a terminal device; and the sending unit is configured to send the system message.

[0085] In a possible implementation, the second indication information is used to indicate that the cell of the network device allows the first type of terminal device to reside.

[0086] In a possible implementation, the second indication information is used to indicate whether the cell of the network device allows the first type of terminal device to reside.

[0087] In a possible implementation, the second indication information is further used to indicate whether the cell of the network device allows the first type of terminal device to perform same-frequency reselection.

[0088] In a possible implementation, the system message is a system message block SIB1.

[0089] In a twelfth aspect, an embodiment of the present application provides a communication device, which may be a first terminal device or a component within the first terminal device, such as a chip or integrated circuit. The communication device may include: a receiving unit and a processing unit. The receiving unit is configured to receive a system message from a network device; the processing unit is configured to obtain second indication information from the system message, where the second indication information is configured to indicate a first type, where the first type is the first type of the terminal device.

[0090] In a possible implementation, the system message is a system message block SIB1.

[0091] In a possible implementation, the processing unit is further configured to: determine whether to allow camping in the cell of the network device according to whether second indication information is obtained from the system message; or,

[0092] Determine whether to allow camping on the cell of the network device according to the second indication information obtained from the system message.

[0093] In a possible implementation manner, the processing unit is specifically configured to: obtain second indication information from the system message, and determine a cell that is allowed to reside in the network device; or,

[0094] No second indication information can be obtained from the system message, and it is determined that camping in the cell of the network device is not allowed.

[0095] In a possible implementation, the processing unit is specifically configured to: the second indication information indicates that the cell of the network device allows the first type of terminal device to reside, and determine the cell that is allowed to reside in the network device; or

[0096] The second indication information indicates that the cell of the network device does not allow the first type of terminal device to reside, and determines that it is not allowed to reside in the cell of the network device.

[0097] In a possible implementation manner, the processing unit is further configured to: determine whether intra-frequency reselection is allowed according to the second indication information.

[0098] In a possible implementation manner, the processing unit is further specifically configured to: the second indication information exists in the system message, and the sixth indication information indicates that the cell of the network device allows intra-frequency reselection, and determine that intra-frequency reselection is allowed; or,

[0099] The second indication information exists in the system message, and the sixth indication information indicates that the cell of the network device is not allowed to perform intra-frequency reselection, thereby determining that intra-frequency reselection is not allowed.

[0100] In one possible implementation, the system message further includes: frequency band information and bandwidth information supported by the network device; the processing unit is specifically configured to: determine whether to allow camping in the cell of the network device based on whether the second indication information is obtained from the system message, and the frequency band information and bandwidth information supported by the network device; or,

[0101] Whether to allow camping on the cell of the network device is determined according to the second indication information and the frequency band information and bandwidth information supported by the network device.

[0102] In one possible implementation, the network device is a network device corresponding to a neighboring area of ​​a service cell of the first terminal device; the communication device also includes a sending unit, and the sending unit is used to: send the second indication information to the network device corresponding to the service cell.

[0103] In a thirteenth aspect, an embodiment of the present application provides a communication device, which may be a first terminal device or a component within the first terminal device, such as a chip or integrated circuit. The communication device may include: a processing unit and a sending unit. The processing unit is configured to generate capability information, the capability information including third indication information, the third indication information being configured to indicate a type of the first terminal device, the type of the first terminal device being either the first type or the second type; and the sending unit is configured to send the capability information to a network device.

[0104] In a possible implementation manner, the communication apparatus further includes a receiving unit, configured to receive a capability request message from the network device.

[0105] In a fourteenth aspect, an embodiment of the present application provides a communication device, which may include: a receiving unit and a processing unit. The receiving unit is configured to receive capability information from a first terminal device, the capability information including third indication information; and the processing unit is configured to determine, based on the third indication information, whether the type of the first terminal device is the first type or the second type.

[0106] In a possible implementation, the communication apparatus further includes a sending unit configured to send a capability request message to the first terminal device.

[0107] In a fifteenth aspect, an embodiment of the present application provides a communication device, which may be a first network device or a component within the first network device, such as a chip or an integrated circuit. The communication device may include a sending unit and a receiving unit. The sending unit is configured to send an Xn interface establishment request message to a second network device, wherein the Xn interface establishment request message includes query information, and the query information is used to inquire whether the second network device supports a first type of terminal device; the receiving unit is configured to receive an Xn interface establishment response message or an Xn interface establishment failure message from the second network device; wherein the Xn interface establishment response message includes fourth indication information, and the fourth indication information is used to indicate whether the second network device supports the first type of terminal device.

[0108] In a sixteenth aspect, an embodiment of the present application provides a communication device, which may be a second network device or a component within the second network device, such as a chip or an integrated circuit. The communication device may include a receiving unit and a sending unit. The receiving unit is configured to receive an Xn interface establishment request message from a first network device, wherein the Xn interface establishment request message includes query information, and the query information is used to inquire whether the second network device supports a first type of terminal device; the sending unit is configured to send an Xn interface establishment response message or an Xn interface establishment failure message to the first network device; wherein the Xn interface establishment response message includes fourth indication information, and the fourth indication information is used to indicate whether the second network device supports the first type of terminal device.

[0109] In the seventeenth aspect, an embodiment of the present application provides a communication device comprising at least one memory and at least one processor, wherein the at least one memory is used to store a computer program, and the at least one processor is used to call and run the computer program from the at least one memory, so that the at least one processor runs the computer program to execute a communication method as described in any one of the first aspect, the second aspect, the third aspect, the sixth aspect, the seventh aspect, and the eighth aspect.

[0110] In aspect 18, an embodiment of the present application provides a communication device comprising at least one memory and at least one processor, wherein the at least one memory is used to store a computer program, and the at least one processor is used to call and run the computer program from the at least one memory, so that the at least one processor runs the computer program to execute a communication method as described in any one of aspect 4 and aspect 5.

[0111] In the nineteenth aspect, an embodiment of the present application provides a computer storage medium, wherein the computer storage medium includes a computer program, and the computer program is used to implement the communication method as described in any one of the first aspect, the second aspect, the third aspect, the sixth aspect, the seventh aspect, and the eighth aspect, or to implement the communication method as described in any one of the fourth aspect and the fifth aspect.

[0112] In the twentieth aspect, an embodiment of the present application provides a chip or a chip system, which includes at least one processor and a communication interface, the communication interface and the at least one processor are interconnected through lines, and the at least one processor is used to run a computer program or instruction to perform a communication method as described in any one of the first aspect, the second aspect, the third aspect, the sixth aspect, the seventh aspect, and the eighth aspect, or a communication method as described in any one of the fourth aspect and the fifth aspect.

[0113] The communication interface in the chip may be an input / output interface, a pin or a circuit, etc.

[0114] In one possible implementation, the chip or chip system described above in this application further includes at least one memory, in which instructions are stored. The memory may be a storage unit within the chip, such as a register, a cache, etc., or a storage unit of the chip (e.g., a read-only memory, a random access memory, etc.).

[0115] In a twenty-first aspect, an embodiment of the present application provides a communication system, the communication system comprising the communication device according to any one of the ninth aspect and the communication device according to any one of the tenth aspect;

[0116] Alternatively, the communication system includes the communication device according to any one of the eleventh aspect and the communication device according to any one of the twelfth aspect;

[0117] Alternatively, the communication system includes the communication device according to any one of the thirteenth aspect and the communication device according to any one of the fourteenth aspect;

[0118] Alternatively, the communication system includes a communication device as described in any one of the fifteenth aspect and a communication device as described in any one of the sixteenth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0119] Figure 1A A schematic diagram of a network architecture that may be involved in embodiments of the present application;

[0120] Figure 1B A schematic diagram of another network architecture that may be involved in embodiments of the present application;

[0121] Figure 2This is a schematic diagram of reducing the bandwidth supported by a performance UE and a legacy network device in an embodiment of the present application;

[0122] Figure 3 A flow chart of a communication method provided in one embodiment of the present application;

[0123] Figure 4 A flow chart of a communication method provided in one embodiment of the present application;

[0124] Figure 5 A flow chart of a communication method provided in one embodiment of the present application;

[0125] Figure 6 A flow chart of a communication method provided in one embodiment of the present application;

[0126] Figure 7 A schematic diagram of the interaction process of an ANR scenario provided in one embodiment of the present application;

[0127] Figure 8 A flow chart of a communication method provided in one embodiment of the present application;

[0128] Figure 9 A flow chart of a communication method provided in one embodiment of the present application;

[0129] Figure 10 A schematic diagram of the structure of a network device provided in one embodiment of the present application;

[0130] Figure 11 A schematic diagram of the structure of a terminal device provided in one embodiment of the present application;

[0131] Figure 12 A schematic diagram of the structure of a network device provided in one embodiment of the present application;

[0132] Figure 13 A schematic diagram of the structure of a terminal device provided for one embodiment of the present application. DETAILED DESCRIPTION

[0133] The solution of the embodiment of the present application can be applied to various communication systems. Specifically, the communication system can be, for example: global system of mobile communication (GSM) system, code division multiple access (CDMA) system, wideband code division multiple access (WCDMA) system, general packet radio service (GPRS), long term evolution (LTE) system, advanced long term evolution LTE-A (LTE advanced) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), fifth generation mobile networks (5G) communication system, new radio (NR) communication system and future sixth generation mobile networks (6G) communication system or even more advanced communication system.

[0134] The following combination Figure 1A and Figure 1B Describe the network architecture that may be involved in the embodiments of the present application. It should be noted that the network architecture and business scenarios described in the embodiments of the present application are intended to illustrate the technical solutions of the embodiments of the present application and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Those skilled in the art will appreciate that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are equally applicable to similar technical problems.

[0135] Figure 1A This is a schematic diagram of a network architecture that may be involved in the embodiments of this application. Figure 1A As shown in FIG, the network architecture includes: a network device and a terminal device. The terminal device can reside in a cell of the network device through a cell selection process.

[0136] Figure 1B This is a schematic diagram of another network architecture that may be involved in the embodiments of this application. Figure 1BAs shown, the network architecture includes: access and mobility management function (AMF), a first network device, a second network device and a terminal device. The first network device and the second network device communicate with each other through the Xn interface (Xninterface), and the AMF communicates with the network device through the NG interface (NG interface). When a terminal device in a connected state moves from the coverage of the first network device to the coverage of the second network device, in order to ensure the continuity of communication and the quality of service of the terminal device, the communication system can transfer the communication link between the terminal device and the original cell (the cell of the first network device) to the new cell (the cell of the second network device). The above process is called switching. Switching can be divided into switching based on the Xn interface and switching based on the NG interface. That is to say, switching can be performed directly between the two network devices. When the Xn interface cannot be established, the two network devices can also interact with switching signaling through the AMF.

[0137] The network device in the embodiments of the present application may be a device that connects a terminal device to a wireless network. The device may be a base station, or various wireless access points, or may refer to a device in an access network that communicates with a terminal device over an air interface through one or more sectors. The base station may be used to convert received air frames into and from IP packets, acting as a router between the terminal device and the rest of the access network, which may include an Internet Protocol (IP) network. The base station may also coordinate attribute management of the air interface. For example, the base station can be a base transceiver station (BTS) in global system of mobile communication (GSM) or code division multiple access (CDMA), a base station (nodeB, NB) in wideband code division multiple access (WCDMA), an evolutionary node B (eNB or eNodeB) in long term evolution (LTE), or a relay station or access point, a base station gNB in ​​a 5G network, a transmission reception point (TRP) or a next generation node B (gNB) in an NR network, or a base station in other future network systems, etc., and is not limited here.

[0138] The terminal device in the embodiments of the present application can be a wireless terminal or a wired terminal. The wireless terminal can be a device that provides voice and / or other business data connectivity to a user, a handheld device with wireless connection function, or other processing equipment connected to a wireless modem. The wireless terminal can communicate with one or more core networks via a wireless access network. The wireless terminal can be a mobile terminal, such as a mobile phone (or "cellular" phone) and a computer with a mobile terminal. For example, it can be a portable, pocket-sized, handheld, computer-built-in or vehicle-mounted mobile device that exchanges voice and / or data with the wireless access network. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), and other devices. A wireless terminal may also be referred to as a system, subscriber unit, subscriber station, mobile station, mobile, remote station, remote terminal, access terminal, user terminal, user agent, user device or user equipment, or a sensor with network access capability, without limitation herein.

[0139] With the evolution of communication protocols and the diversification of application scenarios, a variety of terminal device types have emerged. For example, the new research area "Support for Reduced-Performance NR Devices" proposed by 3GPP in Release 17 is a function that supports narrower bandwidth and lower peak data rate scenarios, mainly providing lightweight communications for high-end machine type communication (MTC) devices. Terminal devices with weaker capabilities suitable for this scenario can be called reduced capability UEs or low-capability UEs. Such devices mainly include wearable devices, surveillance cameras, industrial sensors, etc.

[0140] For the sake of convenience, in the embodiments of the present application, terminal devices with stronger capabilities are referred to as traditional UEs, which may also be referred to as normal / legacy UEs. Compared with legacy UEs, reduced-performance UEs are a type of terminal device that is low-cost, low-complexity, and more energy-efficient. The capabilities of a terminal device include one or more of the following: maximum transmission bandwidth, transmission rate, reliability, delay tolerance, number of antennas, or battery life. The capabilities of different types of terminal devices vary. For example, in the embodiments of the present application, the reduced-performance UE has one or more of the following characteristics:

[0141] (1) Compared to legacy UEs, reduced performance UEs support narrower bandwidths, where the narrower bandwidth is a bandwidth below a predetermined threshold. Optionally, the threshold is 100 MHz. One type supports a maximum bandwidth of 20 MHz, and the other type supports a maximum bandwidth of 5 MHz. It should be noted that the above classification of reduced performance UEs is for illustrative purposes only and is not intended to be limiting.

[0142] (2) Compared to legacy UEs, reduced performance UEs support reduced peak data rates, for example, typically 5 to 10 Mb / s.

[0143] (3) Compared to legacy UEs, the bandwidth supported by a reduced-performance UE is reduced under the same sub-carrier spacing (SCS) and supported physical resource blocks (RRBs). For example, assuming 24 supported PRBs and a sub-carrier spacing of 15 kHz, a reduced-performance UE supports a 5 MHz RF bandwidth, which is smaller than the bandwidth of a legacy UE in Release 15. Legacy UEs in Release 15 support a 100 MHz bandwidth.

[0144] In the current NR protocol (Release 15 protocol), the terminal device reports the upstream and downstream bandwidths it supports to the network device through a bitmap containing 10 bits. The 10 bits correspond to whether the terminal device supports bandwidths of 5MHz, 10MHz, 15MHz, 20MHz, 25MHz, 30MHz, 40MHz, 50MHz, 60MHz, and 80MHz. According to the current protocol requirements, all terminal devices must support 100MHz bandwidth. Therefore, even though there is no bit indicating whether 100MHz bandwidth is supported in the bitmap reported by the terminal device, the network device will assume that the terminal device supports 100MHz bandwidth. In other words, the network device believes that the bandwidth supported by the terminal device is the bandwidth reported by the terminal device in the bitmap and 100MHz.

[0145] For reduced performance UE, the reduced performance UE cannot support 100MHz and only supports the bandwidth reported in the bit map. Therefore, if the reduced performance UE works on a network device that currently does not support NR Light, the network device will overestimate the capabilities of the reduced performance UE by assuming that such UE supports 100MHz bandwidth. The network device may allow the reduced performance UE to work in this network and allocate resources to it by assuming that the reduced performance UE supports 100MHz, which may cause the reduced performance UE to be unable to work normally on the allocated resources. Therefore, for the reduced performance UE, the network equipment needs to be improved so that the network equipment can support the reduced performance UE.

[0146] For the convenience of description, in the embodiment of the present application, the network device that does not support NR Light is referred to as a "legacy / normal network device" or as a "network device that does not support reduced performance UE". The legacy network device will default to the bandwidth supported by all terminal devices as the bandwidth reported by the terminal device in the bit map and 100MHz. In the embodiment of the present application, the network device that supports reduced performance UE is referred to as a "network device that supports reduced performance UE". It can be understood that the network device that supports reduced performance UE can identify the reduced performance UE and grasp the actual capability of the terminal device through the capability information reported by the terminal device. That is to say, the network device that supports reduced performance UE considers that the bandwidth of the reduced performance UE is the bandwidth reported by it, and the method of reporting the bandwidth may include reporting through the original bit map or reporting through other forms; the network device that supports reduced performance UE considers that the bandwidth of the legacy UE is the bandwidth reported in the bit map and 100MHz; or, the network device that supports reduced performance UE considers that the bandwidth of the legacy UE is the bandwidth reported through the bit map or through other forms and 100M.

[0147] based on Figure 1A and Figure 1B In the network architecture shown, in various service scenarios, according to current protocol implementations, the reduced performance UE may reside in the legacy network device, or the reduced performance UE may be switched to the legacy network device. Figure 2 Schematic diagram of reducing the bandwidth supported by UE and legacy network equipment in the embodiment of the present application. Figure 2As shown, the legacy network device assumes that the reduced performance UE supports 100MHz bandwidth by default, and may allocate uplink and downlink resources that the reduced performance UE may not support to such terminal devices. If the reduced performance UE resides in the legacy network device or is switched to the legacy network device, the legacy network device assumes that the reduced performance UE supports 100MHz by default, and may incorrectly judge the capabilities of the reduced performance UE. For example: the legacy network device may allocate a bandwidth part (Band Width Part, BWP) that the reduced performance UE cannot use, such as allocating a bandwidth part (BWP) to the reduced performance UE. Figure 2 The BWP1, BWP2, and BWP3 shown in FIG result in performance degradation and the UE cannot work normally.

[0148] The following describes several possible business scenarios.

[0149] (1) Cell selection scenario. Based on Figure 1A In the network architecture shown, when a terminal device enters the coverage area of ​​a network device from a power-on or blind area, it searches for a frequency band permitted by the public land mobile network (PLMN) and selects a suitable cell to reside in. This process is called cell selection. The purpose of cell selection is to enable the terminal device to reside in a cell as quickly as possible, allowing it to receive system messages broadcast by the PLMN, initiate random access within the cell, receive paging from the network, and receive cell broadcast services.

[0150] The cell selection process is as follows: After powering on, a terminal device first selects a suitable PLMN and then selects a cell based on the selected PLMN. The cell selection process consists of four steps: cell search, system message reception, cell selection, and cell camping. Only after selecting a cell that meets the camping requirements on the PLMN can the device register with that PLMN. Through cell search, the terminal device achieves frequency and symbol synchronization (downlink synchronization) with the cell, obtains the starting position of the downlink frame, and determines the cell's physical-layer cell identity (PCI). After completing the cell search, the terminal device receives system messages from the cell. By reading system messages, the terminal device obtains public information from the network access layer and non-access layer, allowing it to understand the network configuration before initiating a call and adopt appropriate methods to initiate the call. The terminal device can also read some base station capability information from the system messages, such as the bandwidth supported by the target base station and the initial BWP. Based on this information, the terminal device, combined with its own capabilities, determines whether it can support camping on the base station. Next, based on measurement results, the terminal device selects a cell that meets the S criterion for camping. Cell residency enables the terminal device to receive system information broadcast by the PLMN, initiate a random access process within the cell, receive network paging, and receive cell broadcast services.

[0151] The S criterion is used to determine whether a cell meets the residency requirement. The S criterion may include: if the cell parameters satisfy Srxlev>0, then the cell meets the residency requirement. Srxlev is the cell reception level value, also known as the S value. The calculation formula for Srxlev is as follows:

[0152] Srxlev=Qrxlevmeas-(Qrxlevmin+Qrxlevminoffset)-Pcompensation

[0153] Among them, Qrxlevmeas is the measured reference signal received power of the cell; Qrxlevmin is the minimum required reference signal received power of the cell; Qrxlevminoffset is the offset value relative to Qrxlevmin; and Pcompensation is the power compensation value.

[0154] It should be noted that the above calculation formula for Srxlev is only a possible example and may have other forms. For example, the parameters in the above formula may have different names or parameters may be added or deleted in the above formula.

[0155] It can be seen that in the existing cell selection process, the terminal device cannot know whether the network device supports reduced performance UE. Therefore, when the reduced performance UE selects a cell according to the above existing process, it may choose to reside in the legacy network device, resulting in the reduced performance UE being unable to work normally.

[0156] (2) Switch scenes. Based on Figure 1B In the network architecture shown, when a terminal device in a connected state moves from the coverage of a first network device to the coverage of a second network device, in order to ensure the continuity of communication and the quality of service of the terminal device, the communication system can transfer the communication link between the terminal device and the original cell (the cell of the first network device) to the new cell (the cell of the second network device). The above process is called switching. The switching process is controlled by the network device. The network device sends relevant configuration information to the terminal device. The terminal device completes the switching measurement according to the configuration information and reports the measurement results to the network device based on the measurement reporting trigger condition. The switching process is completed under the control of the network device to ensure uninterrupted communication services.

[0157] The handover process based on the Xn interface is as follows: The source network device (e.g., the first network device) makes a handover decision based on the measurement results reported by the terminal device and other factors. The source network device selects a target network device (e.g., the second network device) and sends a handover request message to it. Based on the information obtained, the target network device determines whether to allow the handover. If so, it sends a handover confirmation message to the source network device. If not, it sends a handover preparation failure message to the source network device.

[0158] The switching process based on the NG interface is similar to the switching process based on the Xn interface. The difference is that the switching signaling between the source network device and the target network device needs to be forwarded by the core network device AMF.

[0159] In the existing handover process, when the source network device sends a handover request message to the target network device, it is not certain whether the target network device supports reduced-performance UEs. In other words, it is not certain whether the target network device is a legacy network device or a network device that supports reduced-performance UEs. Therefore, when the terminal device to be handed over is a reduced-performance UE, according to the existing handover process, the source network device may hand over the reduced-performance UE to the legacy network device, causing the reduced-performance UE to not function properly.

[0160] (3) ANR scenario. In order to reduce the burden of network administrators manually managing neighboring cell relations (NCR), the automatic neighbor relation (ANR) function was introduced in the 3GPP protocol Release 15 version. For cells configured with the ANR function, the network device instructs the terminal device of its serving cell to detect the new target cell and read the global and physical identifiers of the target cell (i.e., global and physical IDs, such as NR CGI / NR PCI, ECGI / PCI). The neighbor information read by the terminal device will be reported to the network device through the cell global identifier procedure report (CGI procedure report), and the network device will store the neighbor information in the neighbor relation table (NCRT) of the serving cell. This avoids the possibility of pilot leakage in the process of adding neighbor relations, which may cause the network device to mistakenly add neighbor cells and affect the quality and stability of the system.

[0161] Combine Figure 1B The network architecture shown assumes that the terminal device resides in the cell of the first network device, that is, the cell of the first network device is the service cell of the terminal device. When the terminal device detects the cell of the second network device, the global and physical identifiers of the detected cell (that is, global and physical IDs, for example, NR CGI / NR PCI, ECGI / PCI) are reported to the first network device, so that the first network device can detect, create, delete, etc. neighboring cell relationships based on the information reported by the terminal device. Furthermore, in the subsequent switching process, the first network device can select the target network device based on these neighboring cell relationships. During the ANR measurement reporting process, the terminal device will report the CGI procedure report corresponding to the PCI, which includes CGI, PLMN ID, tracking area code (TAC), etc.

[0162] As can be seen, in the existing ANR process, the CGI procedure report received by the first network device from the terminal device does not contain information about whether the cell of the other network device supports reduced-performance UEs. In other words, based on the information in the CGI procedure report, the first network device cannot determine whether the second network device is a legacy network device or a network device that supports reduced-performance UEs. Therefore, in the subsequent handover process, the first network device may hand over the reduced-performance UE to the legacy network device, causing the reduced-performance UE to fail to operate normally.

[0163] In order to solve at least one of the above problems, an embodiment of the present application provides a communication method that can prevent a UE with reduced performance from residing in a legacy network device, or prevent a UE with reduced performance from switching to a legacy network device.

[0164] The following describes the technical solution of the present application in detail with reference to several specific embodiments in conjunction with the accompanying drawings. The following specific embodiments can be combined with each other, and the same or similar concepts or processes will not be repeated in some embodiments.

[0165] Figure 3 The flow chart of the communication method provided by one embodiment of the present application is shown in FIG. The communication method of this embodiment can be applied to a switching scenario based on an Xn interface. Figure 3 As shown, the method of this embodiment includes:

[0166] S301: The first network device determines that the type of the first terminal device is the first type.

[0167] In this embodiment, the first network device may also be referred to as the source network device, and the second network device may also be referred to as the target network device. The first terminal device is the terminal device to be switched. In the application scenario of this embodiment, the first terminal device is in a connected state, and a cell of the first network device is the current serving cell of the first terminal device. The first network device makes a switching decision based on the measurement report and other information reported by the first terminal device. In this embodiment, it is assumed that the first network device uses the second network device as the target network device, that is, the first network device attempts to switch the first terminal device to the cell of the second network device.

[0168] This application involves multiple types of terminal devices, and the first type is one of the multiple types. It should be understood that there can be multiple ways to classify the types of terminal devices.

[0169] In one example, the multiple types of terminal devices may be classified based on their capabilities. These capabilities may include one or more of the following: maximum transmission bandwidth, transmission rate, reliability, latency tolerance, number of antennas, or battery life. Different types of terminal devices may have different capabilities.

[0170] Optionally, the multiple types of terminal devices may include a first type and a second type. The capabilities of the first type of terminal device are lower than those of the second type of terminal device. Exemplarily, the first type of terminal device may be a reduced-performance UE, and the second type of terminal device may be a terminal device with higher capabilities than the reduced-performance UE. For example, the second type of terminal device may be a legacy UE. As can be seen from the foregoing description, the legacy UE has higher capabilities than the reduced-performance UE in terms of maximum transmission bandwidth, transmission rate, and so on.

[0171] S302: The first network device sends a handover request message (HANDOVER REQUEST message) to the second network device, where the handover request message includes first indication information, and the first indication information includes identification information of the first type.

[0172] S303: The second network device sends a handover confirmation message (HANDOVER REQUESTACKNOWLEDGE message) or a handover preparation failure message (HANDOVER PREPARATION FAILURE message) to the first network device.

[0173] In the existing handover process, the first network device sends a handover request message (HANDOVERREQUEST message) to the second network device. The handover request message includes the configuration information and progress information of the ongoing service of the terminal device to be switched. For example, the handover request message includes one or more of the following information: the progress of the current quality of service flow (QoS flow), the established protocol data unit (PDU) session (sessions) and related configurations and associated data radio bearers (DRBs), the terminal device's security capabilities (UESecurity Capabilities IE) and access layer security information (AS Security Information), etc. In this way, the second network device can determine whether to agree to the handover based on the information carried in the handover request message.

[0174] In one exemplary embodiment, the switching request message may include capability information of the first terminal device. The capability information may include one or more of the following: maximum transmission bandwidth, transmission rate, reliability, delay tolerance, number of antennas, or battery life, etc. In another example, the switching request message may include a capability identifier or a capability set identifier of the first terminal device. The capability identifier or the capability set identifier is used to indicate the capability information of the terminal device. In this way, the second network device can prepare switching resources for the first terminal device or determine whether to agree to the switching based on the capability information of the first terminal device.

[0175] In this embodiment, the type of the first terminal device is the first type. In order to avoid switching the first terminal device to a network device that does not support the first type, the handover request message (HANDOVER REQUESTmessage) sent by the first network device includes first indication information. The first indication information includes identification information of the first type. The identification information of the first type refers to any information that can be used to identify the first type. In one example, the identification information of the first type may be the name of the first type. For example, when the terminal device of the first type is a reduced capability UE, the identification information of the first type may be a reduced capability UE. In another example, different types may correspond to different indexes, so that the identification information of the first type may be the index corresponding to the first type. Optionally, the switching request message may include configuration and progress information of the ongoing services of the terminal device to be switched, such as the progress of the current quality of service flow (QoSFlow), PDU sessions (PDU Sessions) and related configurations and one or more associated data radio bearers (DRBs); and / or, the switching request message may include relevant information fields of the terminal device, such as: the terminal device's security capabilities (UE Security Capabilities) field, the terminal device's access layer security information (AS SecurityInformation) field, etc., the above fields are used to activate security information for the terminal device under the target network device.

[0176] By carrying the first indication information in the switching request message, which is used to indicate the identification information of the first type, the second network device can determine that the type of the terminal device to be switched is the first type according to the first indication information when receiving the switching request message. Furthermore, the second network device can determine whether to agree to the switching based on whether it supports the terminal device of this type. For example, if the second network device does not support the first type of terminal device, the switching is rejected, and a switching preparation failure message carrying a failure cause value is sent to the first network device. If the second network device supports the first type of terminal device, it can proceed according to the existing switching process (for example, determine whether to agree to the switching based on other information in the switching request message), and send a switching confirmation message to the first network device when it is finally determined to agree to the switching.

[0177] It should be noted that, in the embodiments of the present application, "the second network device supports the first type of terminal device" means that the second network device has the ability to provide network services for the first type of terminal device, and the second network device also allows the first type of terminal device to access its cell. "The second network device does not support the first type of terminal device" may include the following two situations: (1) the second network device does not have the ability to provide network services for the first type of terminal device, for example, the second network device is a legacy network device; (2) the second network device has the ability to provide network services for the first type of terminal device, for example, the second network device is a "network device supporting reduced performance UE", but due to network deployment requirements and policies, traffic control, and other factors, the second network device does not allow the first type of terminal device to access.

[0178] In one possible implementation, if the second network device does not support the first type of terminal device, a first switching preparation failure message is sent to the first network device. In one example, the first switching preparation failure message includes failure information corresponding to the first type. For example, the failure cause (failurecause value) carried in the first switching preparation failure message indicates a switching failure due to non-support of the first type. In another example, the first switching preparation failure message includes a 1-bit information field. Different states of the information field can indicate the cause of failure. For example, if the information field is 1, it indicates that the switching failure is caused by non-support of the first type, and if the information field is 0, it indicates that the switching failure is caused by other reasons.

[0179] In a possible implementation, the first indication information may further include key value indication information, and the key value indication information is used to instruct the second network device to reject the switching under the first condition. Optionally, the first condition may be that the second network device does not support the first type of terminal device. That is, if the second network device does not support or cannot identify the first type of terminal device, the second network device rejects the switching and sends a switching preparation failure message to the first network device. Among them, the "not supported" here can include two situations. The first situation is that the second network device can recognize the first type of identification information, but the second network device does not support the first type of terminal device. The second situation is that the second network device cannot recognize the first type of identification information.

[0180] It should be understood that in this embodiment, there may be multiple ways to carry the first type of identification information and the key value indication information in the first indication information. A possible implementation manner is described below as an example.

[0181] Exemplarily, a new IE or field can be added to the handover request message (HANDOVER REQUEST message), for example, the name of the IE or field is reduced capability UE. The IE or field serves as the first indication information. The IE or field includes first type identification information and key value indication information. Optionally, the definition method of the IE or field refers to the method defined in the 3GPP RAN 3 protocol. The attributes corresponding to the IE or field are shown in Table 1. Referring to Table 1, the attributes of the IE or field may include: name attribute, presence form, key value attribute. The name of the IE or field is the first type of identification information. The presence form of the IE or field is mandatory or optional. The key value of the IE or field can be "reject" or "ignore", that is, key value indication information, indicating whether the second network device adopts a rejection behavior or an ignore behavior when it cannot recognize the IE or field or cannot recognize the identification information carried by the IE or field.

[0182] In addition, referring to Table 1, the IE or field may also include other attributes, such as a range attribute, a type attribute, an importance attribute, and the like. In Table 1, "XXXX" represents the value of the attribute, and this embodiment does not limit the values ​​of other attributes. For example, the presence attribute (Presence) may be defined as "O" (Optional), indicating that the handover request message (HANDOVERREQUEST message) may optionally include the IE or field. The criticality attribute (Criticality) may be defined as "Yes", indicating the importance of the IE or field. And so on.

[0183] For the handover scenario of this embodiment, assuming that the first terminal device to be switched is a reduced performance UE, when the first network device generates a handover request message (HANDOVER REQUEST message), the key value of the IE or field can be set to "reject". In this way, after the second network device receives the handover request message, if the second network device cannot recognize the IE or field (for example, it cannot recognize the name of the IE or field, or cannot recognize the ID name corresponding to the name of the IE or field, or cannot recognize the type pointed to by the IE or field, in which case it indicates that the second network device is a legacy network device), the second network device rejects the handover behavior and sends a handover failure message (HANDOVER PREPARATION FAILURE message) to the first network device. If the second network device can recognize the IE or field (in which case it indicates that the second network device is a network device that supports reduced performance UE), the second network device can continue to execute according to the existing handover process, and when it finally determines to agree to the handover, it sends a handover confirmation message (HANDOVER REQUEST ACKNOWLEDGE message) to the first network device. Therefore, it can effectively prevent the first network device from handing over the reduced performance UE to the legacy network device.

[0184] Table 1

[0185]

[0186] In this embodiment, the first network device is a network device currently providing services to the first terminal device. That is, the first network device supports a first type of terminal device (reduced performance UE). The first network device can also provide services to a second terminal device, which is a second type of terminal device (e.g., a legacy UE). In other words, the first network device can also support a second type of terminal device.

[0187] The communication method provided in this embodiment includes: the first network device determines that the type of the first terminal device is the first type, the first network device sends a switching request message to the second network device, the switching request message includes first indication information, and the first indication information includes identification information of the first type. In this way, after the second network device receives the switching request message, if the second network device does not support the first type of terminal device, it sends a switching preparation failure message to the first network device; if the second network device supports the first type of terminal device, it continues according to the existing switching process, and sends a switching confirmation message to the first network device when it finally determines that the switching is agreed. Through the above process, it is possible to avoid switching the first type of terminal device to a network device that does not support the first type.

[0188] Figure 4 The flow chart of the communication method provided by one embodiment of the present application is as follows. The communication method of this embodiment can be applied to the switching scenario based on the NG interface. Figure 4 As shown, the method of this embodiment includes:

[0189] S401: The first network device determines that the type of the first terminal device is the first type.

[0190] S402: The first network device sends a handover request message (HANDOVER REQUIRED message) to the AMF device, where the handover request message includes first indication information, and the first indication information includes identification information of the first type.

[0191] S403: The AMF device sends a handover request message (HANDOVER REQUEST message) to the second network device, where the handover request message includes the first indication information.

[0192] S404: The second network device sends a handover confirmation message (HANDOVER REQUESTACKNOWLEDGE message) or a handover failure message (HANDOVER FAILURE message) to the AMF device.

[0193] S405: The AMF device sends a handover command message (HANDOVER COMMAND message) or a handover preparation failure message (HANDOVER PREPARATION FAILURE message) to the first network device.

[0194] This embodiment and Figure 3 The embodiment shown is similar, except that this embodiment is applied to a switching scenario based on the NG interface, that is, the switching signaling between the first network device and the second network device is forwarded through the AMF device.

[0195] The following description is made by taking the first terminal device as a reduced performance UE as an example.

[0196] In this embodiment, to prevent a reduced-performance UE from being handed over to a legacy network device, the new IE or field shown in Table 1 is added as first indication information to the fifth indication information, which can be transparently transmitted to the AMF. The fifth indication information can be, for example, the Handover Required Transfer IE. The fifth indication information is included in the Handover Required Transfer message sent by the first network device to the AMF. Because the fifth indication information is a transparent IE for the AMF, the AMF does not interpret the fifth indication information and directly includes it in the Handover Request message and sends it to the second network device. The second network device interprets all contents contained in the fifth indication information. If the second network device can recognize the first indication information (for example, it can recognize the new IE / field in Table 1, or it can recognize the identification information carried by the new IE / field), it indicates that the second network device supports reduced-performance UEs. The second network device then proceeds according to the existing protocol and, upon finalizing its approval of the handover, sends a Handover ACKNOWLEDGE message to the AMF. If the second network device cannot recognize the first indication information (for example, it cannot recognize the new IE / field in Table 1, or cannot recognize the identification information carried by the new IE / field), it means that the second network device is a legacy network device and does not support reduced performance UE. The second network device rejects the switching behavior and sends a handover failure message (HANDOVER FAILURE message) to the AMF. The handover failure message carries the failure cause value.

[0197] If the AMF receives a HANDOVER REQUESTACK NOWLEDGE message from the second network device, it sends a HANDOVER COMMAND message to the first network device to inform the first network device that the second network device has prepared handover resources and can perform handover. If the AMF receives a HANDOVER FAILURE message from the second network device, it sends a HANDOVER PREPARATION FAILURE message to the first network device to notify the first network device that handover preparation has failed.

[0198] If the first network device receives a handover command message (HANDOVER PREPARATION FAILURE message) sent by the AMF, the first network device replies with a handover notification message (HANDOVER NOTIFY message) to the AMF after the handover is completed to inform the AMF that the terminal device has been identified by the cell of the second network device and the handover is completed.

[0199] The communication method provided in this embodiment includes: a first network device determining that a first terminal device is of a first type; the first network device sending a handover request message to an AMF; the handover request message including first indication information, the first indication information including identification information of the first type; and the first indication information being included in fifth indication information that can be transparently transmitted to the AMF, so that the AMF does not interpret the first indication information and directly includes it in a handover request message and sends it to a second network device. After receiving the handover request message, if the second network device does not support the first type of terminal device, the second network device sends a handover failure message to the AMF, including a failure cause value; the AMF sends a handover preparation failure message to the first network device, including a failure cause value or indicating whether the handover failure was caused by not supporting the first type. If the second network device supports the first type of terminal device, the second network device continues according to the existing handover process and sends a handover confirmation message to the AMF when it finally determines that the handover is approved; and the AMF sends a handover command message to the first network device. Through the above process, handover of a first type of terminal device (reduced performance UE) to a network device that does not support the first type (legacy network device) can be avoided.

[0200] Figure 5 This is a flow chart of a communication method provided by an embodiment of the present application. The communication method of this embodiment can be applied to a cell selection scenario. Figure 5 As shown, the method of this embodiment includes:

[0201] S501: The network device generates a system message, where the system message includes second indication information, where the second indication information is used to indicate a first type, where the first type is a type among multiple types of terminal devices.

[0202] S502: The network device sends the system message, and correspondingly, the first terminal device receives the system message.

[0203] The type of the first terminal device is the first type in S501, that is, the first terminal device is a terminal device of the first type.

[0204] S503: The first terminal device obtains second indication information from the system message.

[0205] S504: The first terminal device determines whether it is allowed to reside in the cell of the network device according to the second indication information.

[0206] In the application scenario of this embodiment, the first terminal device is in an idle state, for example, the first terminal device may be performing cell selection or cell reselection.

[0207] In this scenario, after the first terminal device completes the cell search, the first terminal device achieves downlink synchronization with the cell, and the first terminal device can receive the system message broadcast by the network device of the cell. The system message broadcast by the network device is cell-level information. The system message may include a master information block (MIB) and a system information block (SIB), such as SIB1, SIB2, etc. Among them, the MIB contains a limited number of most important and most frequently sent parameters, and the terminal device must use these parameters to obtain other system messages. For example, the MIB may include downlink system bandwidth, PHICH configuration, SFN, etc. Different SIBs can be used to transmit a series of parameters related to different functions. Among them, SIB1 contains parameters used to determine whether a cell is suitable for cell selection, SIB2 contains public wireless resource configuration information, etc.

[0208] The network device of this embodiment may be a "network device supporting reduced performance UE", and the first terminal device may be a reduced performance UE. It should be understood that in the embodiment of the present application, the "network device supporting reduced performance UE" refers to a network device that has the ability to provide network services for reduced performance UE. The "network device supporting reduced performance UE" does not necessarily allow the reduced performance UE to reside. In actual applications, the "network device supporting reduced performance UE" may allow the reduced performance UE to reside, or not allow the reduced performance UE to reside, based on factors such as network deployment requirements and policies, traffic control, etc. The legacy network device does not have the ability to provide network services for the reduced performance UE, and the legacy network device does not allow the reduced performance UE to reside.

[0209] In this embodiment, the system message generated by the network device includes second indication information, and the second indication information is used to indicate a first type, wherein the first type is a type among multiple types of terminal devices. For example, the first type of terminal device may be a reduced performance UE.

[0210] Optionally, the above-mentioned system information may be SIB1, that is, the second indication information in this embodiment may be included in SIB1.

[0211] The second indication information may be used to indicate whether the cell of the network device allows the first type of terminal device to reside. The following two possible implementations are described.

[0212] In the first method, the second indication information is used to indicate that the cell of the network device allows the first type of terminal device to reside. In this method, whether the cell of the network device allows the first type of terminal device to reside is indicated by whether the second indication information exists / is included in the system message. The existence / inclusion of the second indication information in the system message generated by the network device indicates that the cell of the network device allows the first type of terminal device to reside. The absence / inclusion of the second indication information in the system message generated by the network device indicates that the cell of the network device allows the first type of terminal device to reside. The second indication information can be a field or an indication domain. When the field or the indication domain exists in the system message, it means that the network device allows the first type of terminal device to reside.

[0213] In this manner, only the network device that allows the first type of terminal device to reside (it should be understood that the network device must be a network device that supports reduced performance UE) has / includes the second indication information in the system message it generates. That is, the network device that supports reduced performance UE may allow the first type of terminal device to reside, or may not allow the first type of terminal device to reside. Whether it allows the residency is reflected by whether the system message it generates contains the second indication information. The network device that does not allow the first type of terminal device to reside does not / does not include the second indication information in the system message it generates. It should be understood that the above-mentioned not allowing the first type of terminal device to reside includes two situations: one situation is that the network device is a network device that supports reduced performance UE, but due to certain factors, such as network deployment requirements and policies, traffic control, etc., the network device does not allow the first type of terminal device to reside; the other situation is that the network device is a legacy network device and does not have the ability to provide network services for the first type of terminal device.

[0214] Based on this method, after receiving the system message, the first terminal device obtains the second indication information from the system message. The "obtaining" here refers to the action of the first terminal device obtaining the second indication information, and the results of the acquisition include the following two situations: obtaining the second indication information or not obtaining the second indication information.

[0215] The first terminal device determines whether the first terminal device is allowed to reside in the cell of the network device based on whether the second indication information is obtained from the system message (or, based on whether the second indication information exists / is included in the system message). If the first terminal device obtains the second indication information from the system message (or, if the second indication information exists / is included in the system message), it is determined that the first terminal device is allowed to reside in the cell of the network device. If the first terminal device does not obtain the second indication information from the system message (or, if the second indication information does not exist / is not included in the system message), it is determined that the first terminal device is not allowed to reside in the cell of the network device.

[0216] In one example, a new IE or field may be added to a system message, and the new IE or field serves as the second indication information. For a network device that supports reduced-performance UEs, if it allows a first type of terminal device to reside, the new IE or field is present in / included in the system message it generates; if it does not allow a first type of terminal device to reside, the new IE or field is not present in / not included in the system message it generates. For legacy network devices, the new IE or field is not supported, and the new IE or field is not present in / not included in the system message it generates.

[0217] In this way, after receiving the system message, the first terminal device obtains the IE or field from the system message. If the first terminal device obtains the IE or field from the system message (or, if the system message contains / includes the IE or field), it is determined that the first terminal device is allowed to reside in the cell of the network device. If the first terminal device does not obtain the IE or field from the system message (or, if the system message does not contain / includes the IE or field), it is determined that the first type of terminal device is not allowed to reside in the cell of the network device.

[0218] In the second method, the second indication information is used to indicate whether the cell of the network device allows the first type of terminal device to reside. In this method, the second indication information exists / includes in the system message generated by the network device, and the value of the second indication information is a first preset value, indicating that the cell of the network device allows the first type of terminal device to reside. The second indication information exists / includes in the system message generated by the network device, and the value of the second indication information is a second preset value, indicating that the cell of the network device does not allow the first type of terminal device to reside. The second indication information does not exist / does not include in the system message generated by the network device, indicating that the cell of the network device does not allow the first type of terminal device to reside.

[0219] In this manner, for "network devices supporting reduced performance UEs", the system message generated by it contains / includes second indication information, and the value of the second indication information is used to indicate whether the first type of terminal device is allowed to reside. For legacy network devices, that is, network devices that do not have the ability to provide network services for reduced performance UEs, the system message generated by it does not contain / includes the second indication information.

[0220] Since the system message generated by the "network device supporting reduced performance UE" contains / includes the second indication information, while the system message generated by the legacy network device does not contain / does not include the second indication information, the first terminal device can distinguish whether the network device is a "network device supporting reduced performance UE" or a legacy network device based on whether the second indication information exists / includes in the system message.

[0221] Based on this method, after the first terminal device receives the system message, it obtains the second indication information from the system message. The "obtaining" here refers to the action of the terminal device obtaining the second indication information, and the results of the acquisition include the following two situations: obtaining the second indication information and not obtaining the second indication information. It should be understood that the second indication information can be obtained from the system message received from the "network device supporting reduced performance UE", and the second indication information cannot be obtained from the system message received from the legacy network device.

[0222] The first terminal device obtains the second indication information from the system message (or the system message contains / includes the second indication information), indicating that the network device is a "network device that supports reduced performance UE". In this case, the first terminal device determines whether the first terminal device is allowed to reside in the cell of the network device based on the obtained second indication information. If the second indication information indicates that the cell of the network device allows the first type of terminal device to reside, the first terminal device determines that the first terminal device is allowed to reside in the cell of the network device. If the second indication information indicates that the cell of the network device does not allow the first type of terminal device to reside, the first terminal device determines that the first terminal device is not allowed to reside in the cell of the network device.

[0223] The first terminal device cannot obtain the second indication information from the system message (or the system message does not contain / does not include the second indication information), indicating that the network device is a legacy network device. In this case, the first terminal device determines that the first terminal device is not allowed to reside in the cell of the network device.

[0224] In one example, a new IE or field can be added to the system message, and the IE or field serves as the second indication information. The attribute of the IE or field can be an enumeration (ENUMERATED{XXX}) type, for example, {true / false}, {supported / notSupported}, or {1 / 0}. Of course, enumeration can also be omitted, and this embodiment does not specifically limit this. For example, assuming the name of the IE or field is ReducedCapabilityUE-Support, the added ASN.1 is as follows:

[0225] ReducedCapabilityUE-Support··········ENUMERATED{true}············OPTIONAL

[0226] For "network devices supporting reduced performance UEs," this IE or field is present in / included in the system messages it generates. Furthermore, if it allows the first type of terminal device to reside, the value of this IE or field is true, supported, or 1; if it does not allow the first type of terminal device to reside, the value of this IE or field is false, notSupported, or 0. For legacy network devices, this IE or field is not present in / included in the system messages it generates.

[0227] In this way, after the first terminal device receives the system message, it obtains the IE or field from the system message. The first terminal device obtains the IE or field from the system message (or in other words, the system message contains / includes the IE or field), and the value of the IE or field is true or supported or 1, determining that the first terminal device is allowed to reside in the cell of the network device. The first terminal device obtains the IE or field from the system message (or in other words, the system message contains / includes the IE or field), and the value of the IE or field is false or notSupported or 0, determining that the first terminal device is not allowed to reside in the cell of the network device. The first terminal device cannot obtain the IE or field from the system message (or in other words, the system message does not contain / includes the IE or field), determining that the first terminal device is not allowed to reside in the cell of the network device.

[0228] In another example, a new IE or field may be added to the system message to list the types of one or more terminal devices that the network device allows to reside. Assuming that the name of the IE or field is UEType-Supported, the value of the IE or field can be {0, 1, 2}, where 0 corresponds to the first type, 1 corresponds to the second type, and 2 corresponds to the third type. The IE or field indicates that terminal devices of the first, second, and third types are allowed to reside.

[0229] In this way, after the first terminal device receives the system message, it obtains the IE or field from the system message. The first terminal device obtains the IE or field from the system message (or in other words, the system message exists / includes the IE or field), and the types listed in the IE or field include the first type, determining that the first terminal device is allowed to reside in the cell of the network device. The first terminal device obtains the IE or field from the system message (or in other words, the system message exists / includes the IE or field), and the types listed in the IE or field do not include the first type, determining that the first terminal device is not allowed to reside in the cell of the network device. The first terminal device cannot obtain the IE or field from the system message (or in other words, the system message does not exist / includes the IE or field), determining that the first terminal device is not allowed to reside in the cell of the network device.

[0230] In another example, a bitmap may be added to the system message, and the bitmap is used to indicate which types of terminal devices are allowed or not allowed to reside in the network device. For example, taking the example that the types of terminal devices include the first type and the second type, a 2-bit bitmap may be used, and the 2 bits respectively correspond to whether the cell of the network device allows the first type and the second type of terminal devices to reside. Alternatively, taking the example that the types of terminal devices include the first type and the second type, a 1-bit IE or field may be used to indicate whether the cell of the network device allows the first type of terminal devices to reside. For example, if the first type of terminal device is allowed to reside, this bit is 1, and if the first type of terminal device is not allowed to reside, this bit is 0.

[0231] In this way, after the first terminal device receives the system message, it obtains the IE or field from the system message. The first terminal device obtains the IE or field from the system message (or in other words, the system message contains / includes the IE or field), and the bit corresponding to the first type in the IE or field is 1, determining that the first terminal device is allowed to reside in the cell of the network device. The first terminal device obtains the IE or field from the system message (or in other words, the system message contains / includes the IE or field), and the bit corresponding to the first type in the IE or field is 0, determining that the first terminal device is not allowed to reside in the cell of the network device. The first terminal device cannot obtain the IE or field from the system message (or in other words, the system message does not contain / includes the IE or field), determining that the first terminal device is not allowed to reside in the cell of the network device.

[0232] In the above examples, if the first terminal device determines that it is allowed to reside in the cell of the network device, the first terminal device can continue to determine whether other cell residency conditions are met according to the existing process, and determine to reside in the cell of the network device if all other conditions are met.

[0233] Optionally, in addition to the second indication information, the system message may also include frequency band information and bandwidth information supported by the network device, for example, one or more of an uplink frequency band list (frequencyBandList), a downlink frequency band list (frequencyBandList), a carrier bandwidth (carrierBandwidth), configuration information of an uplink initial BWP (initial uplinkBWP), configuration information of an downlink initial BWP (initial downlink BWP), and the like.

[0234] In this way, the first terminal device can determine whether it is allowed to reside in the cell of the network device based on whether the second indication information, the frequency band information, and the bandwidth information are obtained from the system message. Alternatively, the first terminal device can determine whether it is allowed to reside in the cell of the network device based on the second indication information, the frequency band information, and the bandwidth information obtained from the system message.

[0235] For example: Based on the above examples, if the first terminal device determines that the first terminal device is allowed to reside in the cell of the network device based on whether the second indication information is obtained, or based on the obtained second indication information, the first terminal device can continue to determine whether it supports the above-mentioned frequency band information and bandwidth information, etc., and determine whether it is allowed to reside in the cell of the network device based on the S criterion. Based on the above examples, if it is determined that the first terminal device is not allowed to reside in the cell of the network device, the first terminal device can regard the cell as barred, that is, prohibited from residing in the cell.

[0236] It can be understood that in the above two methods, when the second indication information is present or included in the system message, it indicates that the network device is a "network device supporting reduced performance UE." In other words, the first terminal device can determine that the network device is a "network device supporting reduced performance UE" based on the presence or inclusion of the second indication information in the system message.

[0237] Optionally, based on the above two methods, when the first terminal device determines that the network device is a "network device supporting reduced performance UE", the second indication information may also be used to indicate whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection. Accordingly, the method of this embodiment may further include:

[0238] S505: The first terminal device determines whether to allow same-frequency reselection based on the second indication information.

[0239] The following three possible implementations are described below.

[0240] In the first manner, the network device may use the presence / inclusion of the second indication information in the system message to indicate that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection.

[0241] This method can be used in combination with the above-mentioned second method of indicating whether to allow residency. That is, when the network device indicates whether the cell of the network device allows the first type of terminal device to reside by the value of the second indication information (that is, the value of the second indication information is a first preset value, indicating that the cell of the network device allows the first type of terminal device to reside, and the value of the second indication information is a second preset value, indicating that the cell of the network device does not allow the first type of terminal device to reside), the network device indicates that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection by the presence / inclusion of the second indication information in the system message.

[0242] In this manner, the first terminal device determines that the first terminal device is allowed to perform intra-frequency reselection based on the presence / inclusion of the second indication information in the system message. In other words, the first terminal device determines that the first terminal device is allowed to perform intra-frequency reselection based on the second indication information obtained from the system message.

[0243] The first terminal device determines that the first terminal device is not allowed to reselect the same frequency based on the absence / inclusion of the second indication information in the system message. In other words, the first terminal device determines that the first terminal device is not allowed to reselect the same frequency based on the failure to obtain the second indication information from the system message.

[0244] In the second manner, the network device may indicate whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection by using the value of the second indication information. For example, if the value of the second indication information is a first preset value, it indicates that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection, and if the value of the second indication information is a second preset value, it indicates that the cell of the network device does not allow the first type of terminal device to perform intra-frequency reselection.

[0245] This method can be used in combination with the first method of indicating whether to allow residency. That is, when the network device indicates that the first type of terminal device is allowed to reside by the presence / inclusion of the second indication information in the system message, the network device indicates whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection by the value of the second indication information.

[0246] In this manner, when the first terminal device obtains the second indication information from the system message, if the second indication information indicates that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection (for example, the value of the second indication information is a first preset value), the first terminal device determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection. If the second indication information indicates that the cell of the network device does not allow the first type of terminal device to perform intra-frequency reselection (for example, the value of the second indication information is a second preset value), the first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection.

[0247] In one example, the value of the second indication information can be enumerated as {true / false}, or {supported / notSupported}, or {1 / 0}, or {allowed / notAllowed}. Of course, enumeration can also be omitted. The value of the second indication information obtained by the first terminal device is true or supported or 1 or allowed, which determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection. The value of the second indication information obtained by the first terminal device is false or notSupported or 0 or notAllowed, and the first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection.

[0248] In another example, the second indication information may list the types of one or more terminal devices that the network device allows for intra-frequency reselection. For example, the value of the second indication information is {0, 1, 2}, where 0 corresponds to the first type, 1 corresponds to the second type, and 2 corresponds to the third type, indicating that the network device allows terminal devices of the first, second, and third types to perform intra-frequency reselection.

[0249] In this way, after the first terminal device obtains the second indication information from the system message, if the types listed in the second indication information include the first type, it is determined that the cell of the network device allows the first terminal device to perform intra-frequency reselection. If the types listed in the second indication information do not include the first type, it is determined that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection.

[0250] In another example, the second indication information uses a bitmap to indicate which types of terminal devices the network device allows or does not allow to perform intra-frequency reselection. For example, taking the example that the types of terminal devices include the first type and the second type, a 2-bit bitmap can be used, and the 2 bits respectively correspond to whether the cell of the network device allows the first type and the second type of terminal devices to perform intra-frequency reselection. Alternatively, taking the example that the types of terminal devices include the first type and the second type, 1 bit can be used to indicate whether the cell of the network device allows the first type of terminal devices to perform intra-frequency reselection. For example, if the first type of terminal device is allowed to perform intra-frequency reselection, this bit is 1, and if the first type of terminal device is not allowed to perform intra-frequency reselection, this bit is 0.

[0251] In this way, after the first terminal device obtains the second indication information from the system message, if the bit corresponding to the first type in the second indication information is 1, it is determined that the cell of the network device allows the first terminal device to reselect the same frequency; if the bit corresponding to the first type in the second indication information is 0, it is determined that the cell of the network device does not allow the first terminal device to reselect the same frequency.

[0252] In the third manner, the second indication information and the sixth indication information may be used to indicate whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection. The sixth indication information may be indication information used to indicate whether the cell of the network device allows the terminal device (here, the terminal device may be a legacy UE) to perform intra-frequency reselection.

[0253] This method can be used in combination with the first method of indicating whether to allow camping. That is, the network device indicates that the first type of terminal device is allowed to camp by the presence / inclusion of the second indication information in the system message; and the network device indicates whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection by using the second indication information and the sixth indication information.

[0254] This method can also be used in combination with the second method of indicating whether to allow residency as described above. That is, the network device indicates, through the value of the second indication information, whether the cell of the network device allows the first type of terminal device to reside (i.e., the value of the second indication information is a first preset value, indicating that the cell of the network device allows the first type of terminal device to reside, and the value of the second indication information is a second preset value, indicating that the cell of the network device does not allow the first type of terminal device to reside); and the network device indicates, through the second indication information and the sixth indication information, whether the cell of the network device allows the first type of terminal device to perform intra-frequency reselection.

[0255] Specifically, when the second indication information exists / is included in the system message, that is to say, the network device is a "network device supporting reduced-performance UE", if the sixth indication information indicates that the cell of the network device allows the terminal device (the terminal device here may be a legacy UE) to perform intra-frequency reselection, then it means that the cell of the network device allows the first type of terminal device to perform intra-frequency reselection; if the sixth indication information indicates that the cell of the network device does not allow the terminal device (the terminal device here may be a legacy UE) to perform intra-frequency reselection, then it means that the cell of the network device does not allow the first type of terminal device to perform intra-frequency reselection. When the second indication information does not exist / is not included in the system message, that is, the network device is a legacy network device, then it means that the cell of the network device does not allow the first type of terminal device to perform intra-frequency reselection, and the value of the sixth indication information does not need to be considered at this time.

[0256] In this manner, the first terminal device may further receive sixth indication information from the network device. When the system message contains / includes the second indication information (or the first terminal device obtains the second indication information from the system message), the first terminal device determines, based on the sixth indication information, whether the cell of the network device allows the first terminal device to perform intra-frequency reselection.

[0257] Specifically, the system message contains / includes the second indication information (or, the first terminal device obtains the second indication information from the system message), that is, the network device is a "network device that supports reduced-performance UEs", and the sixth indication information indicates that the cell of the network device allows the terminal device (the terminal device here may be a legacy UE) to perform intra-frequency reselection, and the first terminal device determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection. The system message contains / includes the second indication information (or, the first terminal device obtains the second indication information from the system message), and the sixth indication information indicates that the cell of the network device does not allow the terminal device (the terminal device here may be a legacy UE) to perform intra-frequency reselection, and the first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection.

[0258] The second indication information does not exist / is not included in the system message (or the first terminal device cannot obtain the second indication information from the system message), that is, the network device is a legacy network device, and the first terminal device determines that the cell of the network device does not allow the first terminal device to reselect the same frequency.

[0259] The sixth indication information and the second indication information may be included in the same system message or in different system messages.

[0260] Optionally, the sixth indication information may be the intraFreqReselection IE in the system message, or may be other IEs for indicating whether intra-frequency reselection is allowed. The value of intraFreqReselection IE may be enumerated as {allowed / notAllowed}. When the first terminal device obtains the second indication information from the system message (or in other words, the system message contains / includes the second indication information), it indicates that the network device is a "network device that supports reduced performance UEs." In this case, if the value of the intraFreqReselection IE is allowed, the first terminal device determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection; if the value of the intraFreqReselection IE is notAllowed, the first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection. When the first terminal device cannot obtain the second indication information from the system message (or in other words, the system message does not contain / includes the second indication information), it indicates that the network device is a legacy network device. In this case, regardless of whether the value of the intraFreqReselection IE is allowed or notAllowed, the first terminal device determines that the cell of the network device does not allow the first terminal device to perform intra-frequency reselection.

[0261] In the above examples, if the first terminal device determines that the cell of the network device allows the first terminal device to perform intra-frequency reselection, the first terminal device can continue to determine whether other intra-frequency reselection conditions are met according to the existing process, and determine to perform intra-frequency reselection if all conditions are met.

[0262] The communication method provided in this embodiment includes: a network device generates and sends a system message, and the system message includes second indication information, and the second indication information is used to indicate whether the cell of the network device allows the first type of terminal device to reside or whether the first type of terminal device is allowed to reside, so that the terminal device can determine whether it is allowed to reside in the cell of the network device based on the second indication information in the system message. For a reduced performance UE, if it is determined based on the received system message that the network device does not allow the reduced performance UE to reside, it will not reside in the cell of the network device; only when it is determined that the network device allows the reduced performance UE to reside, the cell of the network device will be used as a candidate for cell selection, thereby avoiding the reduced performance UE from residing in the legacy network device. Furthermore, the second indication information is also used to indicate whether the cell of the network device allows the first type of terminal device to perform same-frequency reselection, so that the terminal device determines whether it is allowed to perform same-frequency reselection based on the second indication information. If the network device is a "network device supporting reduced performance UE", for the reduced performance UE, if it is determined based on the received system information that the network device does not allow the reduced performance UE to perform intra-frequency reselection, intra-frequency reselection will not be performed; only when it is determined that the network device allows the reduced performance UE to perform intra-frequency reselection, intra-frequency reselection will be considered, thereby avoiding the reduced performance UE from reselecting to the legacy network device.

[0263] Figure 6 This is a flow chart of a communication method provided by one embodiment of the present application. Figure 6 As shown, the method of this embodiment includes:

[0264] S601: A first network device generates a system message, where the system message includes second indication information, where the second indication information is used to indicate a first type, where the first type is a type among multiple types of terminal devices.

[0265] S602: The first network device sends the system message, and the first terminal device receives the system message.

[0266] The specific implementation of S601 and S602 in this embodiment is the same as Figure 5 S501 and S502 are similar and are not described here.

[0267] S603: The first terminal device obtains second indication information from the system message.

[0268] The application scenario of this embodiment can be the aforementioned ANR scenario. In this scenario, the first terminal device operates in the cell of the second network device. That is, a cell of the second network device is the serving cell of the first terminal device. The first network device is the network device corresponding to the neighboring cell of the serving cell of the terminal device. The first terminal device is in a connected state.

[0269] When the first terminal device operates in a cell of the second network device, the second network device can instruct the first terminal device to measure the neighboring cell. The first terminal device monitors the broadcast of the neighboring cell, for example, monitors the system information (such as MIB, SIB1) broadcast by the first network device, and reads the global and physical IDs (e.g., NR CGI / NR PCI, ECGI / PCI) of the neighboring cell.

[0270] In this embodiment, the system message broadcast by the first network device may include second indication information, and the second indication information is used to indicate the first type. The second indication information is used to indicate that the cell of the first network device allows the first type of terminal device to reside, or the second indication information is used to indicate whether the cell of the first network device allows the first type of terminal device to reside. For example, when the first type is a reduced performance UE, the second indication information indicates whether the cell of the first network device allows or allows the reduced performance UE to reside. That is, in this embodiment, the second network device can obtain the first network device's permission for the reduced performance UE to reside by instructing the first terminal device to monitor the system message of the first network device.

[0271] and Figure 5 Similar to the embodiment shown, optionally, the system message in this embodiment may be SIB1.

[0272] It should be understood that in this embodiment, the manner in which the second indication information is carried in the system message is the same as Figure 5 The embodiments shown are similar and will not be described in detail here.

[0273] S604: The first terminal device sends the second indication information or the determination result corresponding to the second indication information to the second network device; wherein the determination result is the result obtained by the first terminal device judging whether the first network device allows the first type of terminal device to reside based on the second indication information.

[0274] In this embodiment, after the first terminal device parses the system message broadcast by the first network device to obtain the second indication information, it can send the second indication information to the second network device, so that the second network device knows whether the first network device allows the first type of terminal device to reside.

[0275] There are many ways to implement the first terminal device sending the second indication information to the second network device. This embodiment does not specifically limit this. Several possible implementations are described below as examples.

[0276] In one possible implementation, after receiving SIB1 from the first network device, the first terminal device sends the second indication information parsed from SIB1 to the second network device. For example, the second indication information may be sent in a CGI procedure report or a measurement report.

[0277] In another possible implementation, after the first terminal device receives SIB1 from the first network device, it determines whether the first network device allows the first type of terminal device to reside based on the second indication information in SIB1, and sends the determination result to the second network device. For example, this can be done by adding an information field in a measurement report, a CGI procedure report, or other reports. For example, if the determination result is that the first network device allows the first type of terminal device to reside, the newly added field can be set to 1 or true or supported; if the determination result is that the first network device does not allow the first type of terminal device to reside, the newly added field can be set to 0 or false or notsupported.

[0278] After receiving the second indication information, the second network device may store the second indication information, for example, in a neighbor cell relation table (NCRT).

[0279] The following describes the specific interaction process by taking the second indication information carried in the CGI procedure report as an example. Figure 7 The following is a schematic diagram of the interaction process of the ANR scenario provided by an embodiment of the present application. Figure 7 As shown, it is assumed that the first terminal device operates in cell A of the second network device. The first terminal device detects cell B of the first network device. The ANR interaction process includes:

[0280] S701: The first terminal device sends the detected PCI of cell B to the second network device.

[0281] S702: If the second network device finds that the PCI of cell B reported by the first terminal device is unrecognizable, it instructs the first terminal device to obtain the neighboring cell information corresponding to the PCI.

[0282] S703: The first terminal device receives the SIB1 of cell B and generates a CGI procedure report based on the neighboring cell information parsed from the SIB1. The CGI procedure report includes one or more of: a PLMN list, a RAN area code (RANAC), a tracking area code (TAC), a cell ID (Cell ID), a frequency band list, and the second indication information.

[0283] S704: The first terminal device sends the CGI procedure report to the second network device.

[0284] In the existing ANR process, the first terminal device receives the SIB1 of cell B, parses the SIB1 to obtain the PLMN list, TAC, Cell ID, and frequency band list corresponding to cell B, and carries this information in a CGI procedure report and sends it to the second network device. In this embodiment, when the SIB1 of cell B contains the second indication information, the first terminal device can also carry the second indication information obtained by parsing the SIB1 of cell B in a CGI procedure report or other reports. In this way, after receiving the report from the UE, the second network device can know whether the first network device allows the first type of terminal device to reside based on the second indication information carried therein.

[0285] In this embodiment, by adding the second indication information in SIB1 to the CGI procedure report, no delay is caused by measuring or reading information related to other neighboring cells.

[0286] To distinguish them, the CGI procedure report in the existing ANR process is referred to as the original CGI procedure report, and the CGI procedure report in this embodiment is referred to as the enhanced CGI procedure report. For example, the contents included in the enhanced CGI procedure report in this embodiment are shown in Table 2.

[0287] Table 2 Enhanced CGI procedure report

[0288]

[0289] S705: The second network device initiates an Xn connection establishment request to the first network device or the first network device initiates an Xn connection establishment request to the second network device to establish an Xn connection between the network devices. The Xn connection is used for a subsequent handover process.

[0290] Alternatively, the handover between the first network device and the second network device is performed through the NG interface, that is, the handover request message and the handover success / failure message are forwarded via the core network AMF. For example, when the Xn connection between the first network device and the second network device cannot be established, the handover between the first network device and the second network device will be performed through the NG interface.

[0291] In this embodiment, when the second network device initiates a handover, it uses information obtained from the CGI procedure report, including information about whether other network devices allow or permit the first type of terminal device (reduced performance UE) to reside, as a judgment condition to select a target network device. For example, if the type of terminal device to be handed over is a reduced performance UE, the second network device selects a network device (e.g., the first network device) that allows the reduced performance UE to reside as the target network device. This can avoid handing over the reduced performance UE to a legacy network device.

[0292] Figure 8 This is a flow chart of a communication method provided by one embodiment of the present application. Figure 8 As shown, the method of this embodiment includes:

[0293] S801: A first terminal device generates capability information, where the capability information includes third indication information, and the third indication information is used to indicate a type of the first terminal device, where the type of the first terminal device is the first type or the second type.

[0294] S802: The first terminal device sends the capability information to the network device.

[0295] Correspondingly, the network device receives the capability information from the first terminal device.

[0296] S803: The network device determines, based on the third indication information in the capability information, whether the type of the first terminal device is the first type or the second type.

[0297] The method of this embodiment can be applied to the capability interaction scenario of a terminal device. The capability interaction scenario of a terminal device may include the following two scenarios.

[0298] Scenario 1: The terminal device proactively reports its capability information to the network device. For example, when the terminal device attaches to the network or performs a tracking area updating (TAU), the terminal device proactively reports the capability information.

[0299] Scenario 2: The network device inquires the terminal device about the capability information of the terminal device. For Scenario 2, before S801, this embodiment may also include: S800: The network device sends a capability request message to the first terminal device, and accordingly, the first terminal device receives the capability request message from the network device. That is to say, when the network device requires the terminal device to report capability information, the network device will send a capability request message (UECapabilityEnquiry) to the terminal device. After the terminal device receives the capability request message (UECapabilityEnquiry), the terminal device reports the UE capability information (UECapabilityInformation) according to the request message.

[0300] Exemplarily, the first type of terminal device may be a reduced performance UE. The second type of terminal device may be a terminal device with higher capabilities than the reduced performance UE, for example, the second type of terminal device may be a legacy UE.

[0301] In this embodiment, the first terminal device includes third indication information in the capability information, which is used to indicate the type of the first terminal device. In this way, the network device can determine the type of the first terminal device based on the received capability information, so that the network device can adopt different processing methods according to the type of the first terminal device. For example, if the type of the first terminal device is the first type (reduced performance UE), it is considered that the bandwidth supported by the first terminal device is the bandwidth reported by it through bitmap or other forms, and when the first terminal device needs to switch, the first terminal device is switched to the network device that supports reduced performance UE. If the type of the first terminal device is the second type (for example, legacy UE), it is considered that the bandwidth of the first terminal device is the bandwidth reported by it through bitmap or other forms and 100MHz.

[0302] Figure 9 This is a flow chart of a communication method provided by an embodiment of the present application. The method of this embodiment can be applied to the Xn interface establishment scenario. Figure 9 As shown, the method of this embodiment includes:

[0303] S901: A first network device sends an Xn interface setup request message (XN SETUPREQUEST message) to a second network device. The Xn interface setup request message includes query information, and the query information is used to query the second network device whether it supports a first type of terminal device.

[0304] In one example, assuming that the first type of terminal device is a reduced capability UE, a new IE or field (eg, reduced capability UEaccessibility) may be added to the Xn interface setup request message (XN SETUP REQUEST message) to inquire whether the second network device supports reduced capability UE.

[0305] The Xn interface establishment request message may also include the application data of the first network device. The application data of a network device includes, but is not limited to, the ID of the network device, the AMF region information corresponding to the network device, the cell and neighboring cell information of the network device, etc. In this way, the second network device can determine whether to establish an Xn interface with the first network device based on the application data of the first network device.

[0306] S902: The second network device sends an XN interface setup response message (XN SETUP RESPONSE message) or an XN interface setup failure message (XN SETUP FAILURE message) to the first network device, wherein the Xn interface setup response message includes fourth indication information, and the fourth indication information is used to indicate whether the second network device supports the first type of terminal device.

[0307] If the second network device determines that the Xn interface cannot be established, the second network device sends an Xn interface establishment failure message (XN SETUP FAILURE message) to the first network device.

[0308] If the second network device allows the establishment of the Xn interface, the second network device sends an Xn interface setup response message (XN SETUP RESPONSE message) to the first network device. In this embodiment, the Xn interface setup response message includes fourth indication information. The fourth indication information can have various forms, which are not limited in this embodiment. For example, a new bit can be added to the Xn interface setup response message, or an existing bit can be reused to represent the fourth indication information. If the second network device supports the first type of terminal device, the bit is set to 1; if the second network device does not support the first type of terminal device, the bit is set to 0. In this way, the first network device can learn whether the second network device supports the first type of terminal device based on the fourth indication information.

[0309] Of course, the Xn interface setup response message (XN SETUP RESPONSE message) may also include the application data of the second network device. In this way, the first network device can obtain relevant information of the second network device based on the application data of the second network device.

[0310] The first network device may also store application data and the fourth indication information of the second network device. When the first network device needs to initiate a handover for a first type of terminal device, it may determine, based on the stored fourth indication information of each network device, which target network device to handover the first type of terminal device to. For example, when the first network device needs to initiate a handover for a reduced performance UE, it may select, based on the stored fourth indication information of each network device, a network device that supports reduced performance UEs as the target network device. This avoids handover of a reduced performance UE to a network device that does not support reduced performance UEs.

[0311] The present application provides a communication device, which may be a network device or a component within the network device, such as a chip or integrated circuit. The following description uses a network device as an example. Those skilled in the art will appreciate that the following network device may be replaced with a communication device such as a chip or integrated circuit. Figure 10 This is a schematic diagram of the structure of the network device provided in the embodiment of the present application. Figure 10 As shown, the network device 10 of this embodiment may include: one or more of a processing unit 11, a sending unit 12, and a receiving unit 13. The network device of this embodiment is introduced below in combination with different application scenarios.

[0312] The network device of this embodiment can be applied to a handover scenario. In a handover scenario, the network device 10 of this embodiment can serve as a first network device. In this case, the network device 10 may include a processing unit 11, a sending unit 12, and a receiving unit 13. The processing unit 11 is configured to determine that the type of the first terminal device is the first type; the sending unit 12 is configured to send a handover request message, wherein the handover request message includes first indication information, and the first indication information includes identification information of the first type; and the receiving unit 13 is configured to receive a handover confirmation message or a handover preparation failure message.

[0313] In a possible implementation manner, the first indication information further includes key value indication information, where the key value indication information is used to instruct the second network device to reject the switching under the first condition.

[0314] In one possible implementation, the receiving unit 13 is specifically used to: receive a switching confirmation message from a second network device, where the second network device supports the first type of terminal device; or receive a first switching preparation failure message from the second network device, where the first switching preparation failure message includes failure information corresponding to the first type, and the second network device does not support the first type of terminal device.

[0315] In one possible implementation, the sending unit 12 is specifically used to: send the switching request message to the second network device; or, send the switching request message to the second network device through the access and mobility management function AMF device.

[0316] The network device of this embodiment can be used to implement the following Figure 3 and Figure 4 The communication method executed by the first network device in the method embodiment shown has similar implementation principles and technical effects, which will not be described here in detail.

[0317] In a handover scenario, the network device 10 of this embodiment can also serve as a second network device. In this case, the network device 10 may include a receiving unit 13 and a sending unit 12. The receiving unit 13 is configured to receive a handover request message, wherein the handover request message includes first indication information, wherein the first indication information includes identification information of a first type, where the first type is the first type of the terminal device, or the first type is the type of the first terminal device. The sending unit 12 is configured to send a handover confirmation message or a handover preparation failure message.

[0318] In a possible implementation, the switching request message further includes capability information of the first terminal device, and the type of the first terminal device is the first type.

[0319] In a possible implementation manner, the first indication information further includes key value indication information, where the key value indication information is used to instruct the second network device to reject the switching under the first condition.

[0320] In one possible implementation, the receiving unit 13 is specifically used to: receive a switching request message sent by the first network device; or, receive a switching request message from the first network device through an access and mobility management function AMF device.

[0321] The network device of this embodiment can be used to implement the following Figure 3 and Figure 4 The communication method executed by the second network device in the method embodiment shown has similar implementation principles and technical effects, which will not be described here in detail.

[0322] The network device of this embodiment can also be applied to cell selection, cell reselection, or ANR scenarios. In this scenario, the network device 10 may include a processing unit 11 and a sending unit 12. The processing unit 11 is configured to generate a system message, the system message including second indication information, the second indication information being configured to indicate a first type, where the first type is the first type of a terminal device; and the sending unit 12 is configured to send the system message.

[0323] In a possible implementation, the second indication information is used to indicate that the cell of the network device allows the first type of terminal device to reside.

[0324] In a possible implementation, the second indication information is used to indicate whether the cell of the network device allows the first type of terminal device to reside.

[0325] In a possible implementation, the second indication information is further used to indicate whether the cell of the network device allows the first type of terminal device to perform same-frequency reselection.

[0326] In a possible implementation, the system message is a system message block SIB1.

[0327] The network device of this embodiment can be used to implement the following Figures 5 to 7 The communication method executed by the network device in the method embodiment shown has similar implementation principles and technical effects, which will not be described here in detail.

[0328] The network device of this embodiment can also be applied to a terminal device capability interaction scenario. In this scenario, the network device 10 may include a receiving unit 13 and a processing unit 11. The receiving unit 13 is configured to receive capability information from a first terminal device, the capability information including third indication information; and the processing unit 11 is configured to determine, based on the third indication information, whether the first terminal device is of the first type or the second type.

[0329] In a possible implementation, the network device 10 may further include a sending unit 12, and the sending unit 12 is configured to send a capability request message to the first terminal device.

[0330] The network device of this embodiment can be used to implement the following Figure 8 The communication method executed by the network device in the method embodiment shown has similar implementation principles and technical effects, which will not be described here in detail.

[0331] The network device of this embodiment can also be applied to the scenario of establishing an Xn interface. In the scenario of establishing an Xn interface, the network device 10 of this embodiment can serve as the first network device. In this case, the network device 10 may include a receiving unit 13 and a sending unit 12. The sending unit 12 is configured to send an Xn interface establishment request message to the second network device, wherein the Xn interface establishment request message includes query information, and the query information is used to inquire whether the second network device supports the first type of terminal device; the receiving unit 13 is configured to receive an Xn interface establishment response message or an Xn interface establishment failure message from the second network device; wherein the Xn interface establishment response message includes fourth indication information, and the fourth indication information is used to indicate whether the second network device supports the first type of terminal device.

[0332] The network device of this embodiment can be used to implement the following Figure 9 The communication method executed by the first network device in the method embodiment shown has similar implementation principles and technical effects, which will not be described here in detail.

[0333] In the Xn interface establishment scenario, the network device 10 of this embodiment can also serve as a second network device. In this case, the network device 10 may include a receiving unit 13 and a sending unit 12. The receiving unit 13 is configured to receive an Xn interface establishment request message from the first network device, the Xn interface establishment request message including query information for inquiring whether the second network device supports a first type of terminal device; the sending unit 12 is configured to send an Xn interface establishment response message or an Xn interface establishment failure message to the first network device; the Xn interface establishment response message includes fourth indication information for indicating whether the second network device supports the first type of terminal device.

[0334] The network device of this embodiment can be used to implement the following Figure 9 The communication method executed by the second network device in the method embodiment shown has similar implementation principles and technical effects, which will not be described here in detail.

[0335] The present application provides a communication device, which may be a terminal device or a component within the terminal device, such as a chip or integrated circuit. The following description uses the terminal device as an example. Those skilled in the art will appreciate that the terminal device below may be replaced with a communication device such as a chip or integrated circuit. Figure 11 This is a schematic diagram of the structure of the terminal device provided in the embodiment of the present application. Figure 11 As shown, the terminal device 20 of this embodiment may include: one or more of a processing unit 21, a sending unit 22, and a receiving unit 23. The terminal device of this embodiment is introduced below in combination with different application scenarios.

[0336] The terminal device of this embodiment can be used in cell selection, cell reselection, or ANR scenarios. In this scenario, the terminal device 10 of this embodiment can serve as a first terminal device. In this case, the terminal device 10 can include a receiving unit 23 and a processing unit 21. The receiving unit 23 is configured to receive a system message from a network device; the processing unit 21 is configured to obtain second indication information from the system message, where the second indication information is configured to indicate a first type, where the first type is the first type of the terminal device.

[0337] In a possible implementation, the system message is a system message block SIB1.

[0338] In a possible implementation, the processing unit 21 is further configured to: determine whether to allow camping in the cell of the network device according to whether second indication information is obtained from the system message; or,

[0339] Determine whether to allow camping on the cell of the network device according to the second indication information obtained from the system message.

[0340] In a possible implementation, the processing unit 21 is specifically configured to: obtain second indication information from the system message, and determine a cell that is allowed to reside in the network device; or,

[0341] No second indication information can be obtained from the system message, and it is determined that camping in the cell of the network device is not allowed.

[0342] In a possible implementation, the processing unit 21 is specifically configured to: the second indication information indicates that the cell of the network device allows the first type of terminal device to reside, and determine the cell allowed to reside in the network device; or

[0343] The second indication information indicates that the cell of the network device does not allow the first type of terminal device to reside, and determines that it is not allowed to reside in the cell of the network device.

[0344] In a possible implementation, the processing unit 21 is further configured to determine whether intra-frequency reselection is allowed according to the second indication information.

[0345] In a possible implementation, the processing unit 21 is further specifically configured to: when the second indication information exists in the system message and the sixth indication information indicates that the cell of the network device allows intra-frequency reselection, determine that intra-frequency reselection is allowed; or,

[0346] The second indication information exists in the system message, and the sixth indication information indicates that the cell of the network device is not allowed to perform intra-frequency reselection, thereby determining that intra-frequency reselection is not allowed.

[0347] In one possible implementation, the system message further includes: frequency band information and bandwidth information supported by the network device; the processing unit 21 is specifically configured to: determine whether to allow camping in the cell of the network device based on whether the second indication information is obtained from the system message, and the frequency band information and bandwidth information supported by the network device; or,

[0348] Whether to allow camping on the cell of the network device is determined according to the second indication information and the frequency band information and bandwidth information supported by the network device.

[0349] In one possible implementation, the network device is a network device corresponding to a neighboring area of ​​a service cell of the first terminal device; the terminal device 10 may further include a sending unit 22, and the sending unit 22 is used to: send the second indication information to the network device corresponding to the service cell.

[0350] The terminal device of this embodiment can be used to implement Figures 5 to 7 The communication method executed by the terminal device in the method embodiment shown has similar implementation principles and technical effects, which will not be described here in detail.

[0351] The terminal device of this embodiment can also be applied to a terminal device capability interaction scenario. In this scenario, the terminal device 20 may include a sending unit 22 and a processing unit 21. The processing unit 21 is configured to generate capability information, wherein the capability information includes third indication information, and the third indication information is configured to indicate the type of the first terminal device, where the type of the first terminal device is either the first type or the second type. The sending unit 22 is configured to send the capability information to the network device.

[0352] In a possible implementation, the terminal device 20 may further include a receiving unit 23, wherein the receiving unit 23 is configured to receive a capability request message from the network device.

[0353] The terminal device of this embodiment can be used to implement Figure 8The communication method executed by the terminal device in the method embodiment shown has similar implementation principles and technical effects, which will not be described here in detail.

[0354] Figure 12 This is a schematic diagram of the structure of the network device provided in the embodiment of the present application. Figure 12 As shown, the network device 30 of this embodiment may include: a processor 31, a memory 32, and a communication interface 33. The number of the processor 31 may be one or more, and the number of the memory 32 may be one or more.

[0355] The memory 32 is used to store computer programs; the communication interface 33 is used to communicate data or signals with other network devices or terminal devices. The processor 31 is used to execute the computer programs stored in the memory 32 to implement the following Figure 3 and Figure 4 The communication method performed by the first network device in the method embodiment shown, or, implementing the following Figure 3 and Figure 4 The communication method performed by the second network device in the method embodiment shown, or, implementing the following Figures 5 to 7 The communication method executed by the network device in the method embodiment shown in FIG8 , or the communication method executed by the network device in the method embodiment shown in FIG8 , or the communication method executed by the network device in the method embodiment shown in FIG8 , or Figure 9 The communication method performed by the first network device in the method embodiment shown, or, implementing the following Figure 9 The communication method is performed by the second network device in the method embodiment shown.

[0356] Optionally, the memory 32 may be independent or integrated with the processor 31. When the memory 32 is a device independent of the processor 31, the network device 30 may further include a bus 34 for connecting the memory 32 and the processor 31.

[0357] In one possible implementation, Figure 10 The processing module 11 can be integrated into the processor 31 , and the receiving module 13 and the sending module 12 can be integrated into the communication interface 33 .

[0358] In a possible implementation, the processor 31 may be used to implement the signal processing operation of the network device in the above method embodiment, and the communication interface 33 may be used to implement the signal receiving and sending operation of the network device in the above method embodiment.

[0359] The network device provided in this embodiment can be used to execute the method executed by the network device in the above method embodiment. Its implementation principle and technical effects are similar and will not be repeated here.

[0360] Figure 13This is a schematic diagram of the structure of the terminal device provided in the embodiment of the present application. Figure 13 As shown, the terminal device 40 of this embodiment includes: a processor 41, a memory 42, and a transceiver 43. The number of the processor 41 can be one or more, and the number of the memory 42 can be one or more.

[0361] The memory 42 is used to store computer programs; the transceiver 43 is used to communicate data or signals with network devices. The processor 41 is used to execute the computer programs stored in the memory 42 to achieve Figures 5 to 7 The communication method executed by the terminal device in the embodiment of the method shown, or, implementing Figure 8 The communication method in the method embodiment shown is executed by a terminal device.

[0362] Optionally, the memory 42 may be independent or integrated with the processor 41. When the memory 42 is a device independent of the processor 41, the terminal device 40 may further include a bus 44 for connecting the memory 42 and the processor 41.

[0363] In one possible implementation, Figure 11 The processing module 21 can be integrated into the processor 41, and the receiving module 23 and the sending module 22 can be integrated into the transceiver 43.

[0364] In a possible implementation, the processor 41 may be used to implement the signal processing operation of the terminal device in the above method embodiment, and the transceiver 43 may be used to implement the signal transceiver operation of the terminal device in the above method embodiment.

[0365] The terminal device provided in this embodiment can be used to execute the method executed by the terminal device in the above method embodiment. Its implementation principle and technical effects are similar and will not be repeated here.

[0366] An embodiment of the present application provides a computer storage medium, which includes a computer program. The computer program is used to implement the method executed by the network device in the above method embodiment, or to implement the method executed by the terminal device in the above method embodiment.

[0367] An embodiment of the present application also provides a chip or chip system, which includes at least one processor and a communication interface, the communication interface and the at least one processor are interconnected by a line, and the at least one processor is used to run a computer program or instruction to implement the method executed by the network device in the above method embodiment, or to implement the method executed by the terminal device in the above method embodiment.

[0368] The communication interface in the chip may be an input / output interface, a pin or a circuit, etc.

[0369] In one possible implementation, the chip or chip system described above in this application further includes at least one memory, in which instructions are stored. The memory may be a storage unit within the chip, such as a register, a cache, etc., or a storage unit of the chip (e.g., a read-only memory, a random access memory, etc.).

[0370] An embodiment of the present application also provides a computer program product, which includes computer program code. When the computer program code is run on a computer, the computer executes the method executed by the network device in the above method embodiment, or implements the method executed by the terminal device in the above method embodiment.

[0371] The embodiment of the present application also provides a communication system, including a first network device and a second network device. The first network device and the second network device can be used as follows: Figure 10 or Figure 12 In some scenarios, the first network device and the second network device can implement the following Figure 3 or Figure 4 In other scenarios, the first network device and the second network device can implement the following Figure 9 The communication method shown.

[0372] The embodiment of the present application also provides a communication system, including: a network device and a terminal device. The network device can be used as follows Figure 10 or Figure 12 The structure shown in the figure, the terminal device can adopt Figure 11 or Figure 13 In some scenarios, network devices and terminal devices can be used to implement Figures 5 to 7 In other scenarios, the network device and the terminal device can be used to implement the following communication method: Figure 8 The communication method shown.

[0373] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules is merely a logical function division. In actual implementation, there may be other division methods, such as multiple modules can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or module, which can be electrical, mechanical or other forms.

[0374] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical units, that is, they may be located in one place or distributed across multiple network elements. Some or all of the modules may be selected to achieve the purpose of the solution of this embodiment according to actual needs.

[0375] In addition, the functional modules in the various embodiments of the present application may be integrated into a single processing unit, or each module may exist physically separately, or two or more modules may be integrated into a single unit. The above-mentioned modules may be implemented in the form of hardware or hardware plus software functional units.

[0376] The above-mentioned integrated module implemented in the form of a software functional module can be stored in a computer-readable storage medium. The above-mentioned software functional module is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) or a processor to perform some steps of the method described in various embodiments of the present application.

[0377] It should be understood that the processor described above may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASICs), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly executed by a hardware processor or by a combination of hardware and software modules within the processor.

[0378] The memory may include a high-speed RAM memory, and may also include non-volatile storage NVM, such as at least one disk memory, and may also be a USB flash drive, a mobile hard disk, a read-only memory, a magnetic disk or an optical disk.

[0379] A bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be categorized as address buses, data buses, and control buses. For ease of illustration, the buses in the drawings of this application are not limited to just one bus or just one type of bus.

[0380] The storage medium may be implemented by any type of volatile or non-volatile memory device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The storage medium may be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0381] An exemplary storage medium is coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and storage medium can be located in application specific integrated circuits (ASICs). Of course, the processor and storage medium can also exist as discrete components in an electronic device or a main control device.

Claims

1. A communication method, characterized in that: The method comprises: Generate a system message; wherein, when the system message does not include the second indication information, the first type of terminal device is not allowed to reside in the cell of the network device; when the system message includes the second indication information, the second indication information is used to indicate whether the first type of terminal device is allowed to perform intra-frequency reselection, and the first type of terminal device is a reduced performance RedCap terminal device; Sending the system message; Among them, the value of the second indication information is allowed or notAllowed. When the value of the second indication information is allowed, it indicates that the first type of terminal device is allowed to reselect the same frequency; when the value of the second indication information is notAllowed, it indicates that the first type of terminal device is not allowed to reselect the same frequency.

2. The method according to claim 1, characterized in that The system message indicates whether the network device is a network device that supports the RedCap terminal device by including the second indication information.

3. The method according to claim 2, characterized in that The system message does not include the second indication information, and the network device is a network device that does not support the Redcap terminal device.

4. The method according to any one of claims 1 to 3, characterized in that The first type of terminal device is one type among multiple types of terminal devices, and the multiple types of terminal devices also include a second type of terminal device, which is a legacy type terminal device. The maximum transmission bandwidth of the legacy type terminal device is greater than that of the RedCap type terminal device.

5. The method according to any one of claims 1 to 3, characterized in that The system message is a system message block SIB1.

6. A communication method, characterized in that: The method comprises: Receive system messages from network devices; When the system message does not include the second indication information, determining that the first type of terminal device is not allowed to reside in the cell of the network device; When the system message includes the second indication information, determining whether to allow the first type of terminal device to perform intra-frequency reselection according to the second indication information, the first type of terminal device being a reduced performance RedCap terminal device; The value of the second indication information is allowed or notAllowed, and determining whether to allow the first type of terminal device to perform intra-frequency reselection according to the second indication information includes: When the value of the second indication information is the allowed, it is determined that the first type of terminal device is allowed to perform intra-frequency reselection; When the value of the second indication information is the notAllowed, it is determined that the first type of terminal device is not allowed to perform same-frequency reselection.

7. The method according to claim 6, characterized in that The system message is a system message block SIB1.

8. The method according to any one of claims 6 to 7, characterized in that The method further comprises: Whether the network device supports the RedCap terminal device is determined based on whether the second indication information can be obtained from the system message.

9. The method according to claim 8, characterized in that When the system message does not include the second indication information, it is determined that the network device does not support the RedCap terminal.

10. The method according to any one of claims 6 to 7 and 9, characterized in that: The first type of terminal device is one type among multiple types of terminal devices, and the multiple types of terminal devices also include a second type of terminal device, which is a legacy type terminal device. The maximum transmission bandwidth of the legacy type terminal device is greater than that of the RedCap type terminal device.

11. A communication device, characterized in that: include: a processing unit, configured to generate a system message, wherein, when the system message does not include the second indication information, the first type of terminal device is not allowed to reside in the cell of the network device; when the system message includes the second indication information, the second indication information is used to indicate whether the first type of terminal device is allowed to perform intra-frequency reselection, and the first type of terminal device is a reduced performance RedCap terminal device; A sending unit, configured to send the system message; Among them, the value of the second indication information is allowed or notAllowed. When the value of the second indication information is allowed, it indicates that the first type of terminal device is allowed to reselect the same frequency; when the value of the second indication information is notAllowed, it indicates that the first type of terminal device is not allowed to reselect the same frequency.

12. The device according to claim 11, characterized in that The system message indicates whether the network device is a network device that supports the RedCap terminal device by including the second indication information.

13. The device according to claim 12, characterized in that The system message does not include the second indication information, and the network device is a network device that does not support the Redcap terminal device.

14. The device according to any one of claims 11 to 13, characterized in that The first type of terminal device is one type among multiple types of terminal devices, and the multiple types of terminal devices also include a second type of terminal device, which is a legacy type terminal device. The maximum transmission bandwidth of the legacy type terminal device is greater than that of the RedCap type terminal device.

15. The device according to any one of claims 11 to 13, characterized in that The system message is a system message block SIB1.

16. A communication device, characterized in that: include: A receiving unit, configured to receive system messages from a network device; a processing unit, configured to, when the system message does not include the second indication information, determine that the first type of terminal device is not allowed to reside in the cell of the network device; When the system message includes the second indication information, determining whether to allow the first type of terminal device to perform intra-frequency reselection according to the second indication information, the first type of terminal device being a reduced performance RedCap terminal device; The value of the second indication information is allowed or notAllowed, and the processing unit is specifically configured to: When the value of the second indication information is the allowed, it is determined that the first type of terminal device is allowed to perform intra-frequency reselection; When the value of the second indication information is the notAllowed, it is determined that the first type of terminal device is not allowed to perform same-frequency reselection.

17. The device according to claim 16, characterized in that The system message is a system message block SIB1.

18. The device according to any one of claims 16 to 17, characterized in that The processing unit is further configured to: Whether the network device supports the RedCap terminal device is determined based on whether the second indication information can be obtained from the system message.

19. The device according to claim 18, characterized in that When the system message does not include the second indication information, it is determined that the network device does not support the RedCap terminal.

20. The device according to any one of claims 16 to 17 and 19, characterized in that The first type of terminal device is one type among multiple types of terminal devices, and the multiple types of terminal devices also include a second type of terminal device, which is a legacy type terminal device. The maximum transmission bandwidth of the legacy type terminal device is greater than that of the RedCap type terminal device.

21. A communication device, characterized in that: include: At least one memory and at least one processor, the at least one memory being used to store a computer program, the at least one processor being used to call and run the computer program from the at least one memory, so that the at least one processor runs the computer program to perform the communication method according to any one of claims 1 to 5.

22. A communication device, characterized in that: include: At least one memory and at least one processor, the at least one memory is used to store a computer program, and the at least one processor is used to call and run the computer program from the at least one memory, so that the at least one processor runs the computer program to execute the communication method according to any one of claims 6 to 10.

23. A computer storage medium, characterized in that The computer storage medium includes a computer program, and the computer program is used to implement the communication method according to any one of claims 1 to 5, or the communication method according to any one of claims 6 to 10.

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