Terminal device, base station device, and wireless communication system

Abstract

This terminal device supports a first function, and comprises: a control unit that selects a random access resource list from among a plurality of random access resource lists including one or more RACH occasions (ROs) to transmit a preamble in random access processing, and selects an RO from the selected random access resource list; a transmission unit that transmits the preamble using the selected RO; and a reception unit that receives a response to the transmitted preamble. The plurality of random access resource lists include a first random access resource list available to the terminal device that supports the first function, and a second random access resource list available to the terminal device that supports the first function and a terminal device that does not support the first function.

Description

Terminal device, base station device, and wireless communication system

[0001] The present invention relates to a terminal device, a base station device, and a wireless communication system.

[0002] In order to reduce the power consumption of base station devices in wireless communication systems, adaptation of common signals / channels including SSB (SS / PBCH Block), PRACH (Physical Random Access Channel), and paging is being discussed in 3GPP (registered trademark) (Non-Patent Document 3).

[0003] SSB adaptation adjusts the transmission cycle of SSB, PRACH adaptation adjusts PRACH resources in the time domain, and paging adaptation controls the concentration of paging occasions in the time domain.

[0004] In PRACH adaptation, the base station device reduces power consumption by disabling certain PRACH resources and going to sleep during certain PRACH transmission periods, for example, depending on the number of terminal devices in the area. The base station device prepares PRACH resources for PRACH adaptation and assigns them to terminal devices that support the PRACH adaptation function. Note that PRACH adaptation uses a Network Energy Saving (NES) function that temporarily puts the base station device into sleep mode, and therefore the PRACH resources for PRACH adaptation are sometimes referred to as NES-compatible PRACH resources.

[0005] 3GPP TS 38.300 V18.2.03GPP TS 38.331 V18.2.0RP-240169

[0006] However, for a terminal device that supports the NES function, the distinction between the NES-compatible PRACH resource and the conventional PRACH resource is not defined. If the distinction between the NES-compatible PRACH resource and the conventional PRACH resource is left up to the terminal device, for example, it is expected that the use of one of the PRACH resources will be biased, which may make it difficult to manage radio resources in a radio communication system.

[0007] Therefore, one disclosure provides a terminal device, a base station device, and a wireless communication system that clarify the method for selecting PRACH resources in PRACH adaptation.

[0008] A terminal device corresponding to a first function, comprising: a control unit that, in a random access process, selects a random access resource list from a plurality of random access resource lists including one or more ROs (RACH Occasions) for transmitting a preamble, and selects an RO from the selected random access resource list; a transmitting unit that transmits the preamble using the selected RO; and a receiving unit that receives a response to the transmitted preamble, wherein the plurality of random access resource lists include a first random access resource list that can be used by a terminal device corresponding to the first function, and a second random access resource list that can be used by a terminal device corresponding to the first function and a terminal device that does not correspond to the first function.

[0009] One disclosure clarifies a method for selecting PRACH resources in PRACH adaptation.

[0010] FIG. 1 is a diagram showing an example of the configuration of a wireless communication system 10. FIG. 2 is a diagram showing an example of the configuration of a base station device 200. FIG. 3 is a diagram showing an example of the configuration of a terminal device 100. FIG. 4 is a diagram showing an example of PRACH adaptation. FIG. 5 is a diagram showing an example of random access processing S100. FIG. 6 is a diagram showing an example of reflection of a first method into a specification. FIG. 7 is a diagram showing an example of random access processing S200. FIG. 8 is a diagram showing an example of reflection of a second method into a specification. FIG. 9 is a diagram showing an example of random access processing S300. FIG. 10 is a diagram showing an example of random access processing S400. FIG. 11 is a diagram showing an example of reflection of a fourth method into a specification. FIG. 12 is a diagram showing an example of reflection into a specification.

[0011] [First Embodiment] A first embodiment will be described.

[0012] 1 is a diagram showing an example of the configuration of a wireless communication system 10. The wireless communication system 10 includes a base station device 200, a terminal device 100, and a terminal device 101. The wireless communication system 10 is a system that supports PRACH adaptation. In order to support PRACH adaptation, the wireless communication system 10 provides NES-compatible PRACH resources, which are PRACH resources for the terminal device 100 that supports the NES function.

[0013] The base station device 200 is a device that is wirelessly connected to and performs wireless communication with the terminal device 100 and the terminal device 101, and is, for example, an eNodeB or a gNodeB. The base station device 200 forms a communication area A200 in which wireless communication is possible.

[0014] The terminal device 100 and the terminal device 101 are communication devices that are wirelessly connected to the base station device 200 and transmit and receive data, and are, for example, smartphones or tablet terminals. The terminal device 100 and the terminal device 101 are equipped with different versions of software. The terminal device 100 is a new terminal device that supports the NES function. On the other hand, the terminal device 101 is a legacy terminal device (old terminal device) that does not support the NES function and is equipped with an older version of software than the terminal device 100.

[0015] The new terminal device 100 can use NES-compatible PRACH resources, but the legacy terminal device 101 cannot use (cannot recognize) NES-compatible PRACH resources. Also, the new terminal device 100 can also use PRACH resources (legacy PRACH resources) that the legacy terminal device 101 can use.

[0016] The base station device 200 supports the NES function. To support PRACH adaptation, when a predetermined condition is satisfied, the base station device 200 disables the NES-compatible PRACH resource and transitions to a sleep state (including stopping monitoring of a predetermined message) for a period including transmission and reception of the NES-compatible PRACH resource.

[0017] 2 is a diagram showing an example of the configuration of the base station device 200. The base station device 200 includes a CPU (Central Processing Unit) 210, a storage 220, a memory 230, an antenna 240, and a wireless communication circuit 250.

[0018] The storage 220 is an auxiliary storage device that stores programs and data, such as a flash memory, a hard disk drive (HDD), or a solid state drive (SSD). The storage 220 stores a wireless communication control program 221 and a PRACH adaptation program 222.

[0019] The memory 230 is an area into which the programs stored in the storage 220 are loaded. The memory 230 may also be used as an area in which the programs store data.

[0020] The wireless communication circuit 250 is a device that performs wireless communication with the terminal device 100 and the terminal device 101 via the antenna 240. The base station device 200 transmits and receives signals (messages) to and from the terminal device 100 and the terminal device 101 via the wireless communication circuit 250.

[0021] The CPU 210 is a processor that loads programs stored in the storage 220 into the memory 230, executes the loaded programs, configures each unit, and realizes each process.

[0022] The CPU 210 executes the wireless communication control program 221 to configure a notification unit, a base station receiving unit, and a base station transmitting unit, and to perform wireless communication control processing. The wireless communication control processing is processing for controlling wireless communication with the terminal device 100 and the terminal device 101. In the wireless communication control processing, the base station device 200 wirelessly connects with the terminal device 100 and the terminal device 101, and transmits signals to the terminal device 100 and the terminal device 101, and receives signals from the terminal device 100 and the terminal device 101.

[0023] The CPU 210 executes the PRACH adaptation program 222 to configure a notification unit, a base station receiving unit, and a base station transmitting unit, and performs PRACH adaptation processing. The PRACH adaptation processing is processing to allocate NES-compatible PRACH resources and transition to a sleep state under predetermined conditions (NES control for PRACH adaptation). Furthermore, in the PRACH adaptation processing, the base station device 200 instructs the terminal device 100 which PRACH resources to use.

[0024] The CPU 210 executes the NES-compatible PRACH allocation module 2221 included in the PRACH adaptation program 222 to configure a notification unit, a base station receiving unit, and a base station transmitting unit, and performs NES-compatible PRACH allocation processing. The NES-compatible PRACH allocation processing is processing for allocating NES-compatible PRACH resources and notifying the terminal device 100.

[0025] The CPU 210 executes the NES control module 2222 included in the PRACH adaptation program 222 to configure a notification unit, a base station receiving unit, and a base station transmitting unit, and performs NES control processing. The NES control processing is processing for invalidating NES-compatible PRACH resources and transitioning to a sleep state under predetermined conditions.

[0026] 3 is a diagram illustrating an example of the configuration of the terminal device 100. The terminal device 100 includes a CPU 110, a storage 120, a memory 130, an antenna 140, and a wireless communication circuit 150.

[0027] The storage 120 is an auxiliary storage device such as a flash memory, HDD, or SSD that stores programs and data. The storage 120 stores a wireless communication program 121 and a random access program 122. The random access program 122 corresponds to the NES function.

[0028] The memory 130 is an area into which the programs stored in the storage 120 are loaded. The memory 130 may also be used as an area in which the programs store data.

[0029] The wireless communication circuit 150 is a device that performs wireless communication with the base station device 200 via the antenna 140. The terminal device 100 transmits and receives signals (messages) to and from the base station device 200 via the wireless communication circuit 150.

[0030] The CPU 110 executes the wireless communication program 121 to configure a control unit, a receiving unit, and a transmitting unit, and to perform wireless communication processing. The wireless communication processing is processing for establishing a wireless connection with the base station device 200 and performing wireless communication. In the wireless communication processing, the terminal device 100 performs wireless communication with the base station device 200, receives signals transmitted by the base station device 200, and transmits signals to the base station device 200.

[0031] The CPU 110 executes the random access program 122 to configure a control unit, a receiving unit, and a transmitting unit, and to perform random access processing. The random access processing is processing executed when wirelessly connecting to the base station device 200. In the random access processing, the terminal device 100 selects, for example, an RO (RACH Occasion) for transmitting a preamble from the PRACH resources, and transmits the preamble.

[0032] <PRACH Adaptation> Figure 4 is a diagram showing an example of PRACH adaptation. The base station device 200 periodically transmits an SSB and an SIB1 (System Information Block) at predetermined intervals (S1-1 to S1-3, S2-1 to S2-3). The base station device 200 then allocates NES-compatible PRACH resources (R3-1 to R3-3) at predetermined timings at the predetermined intervals, and monitors whether a preamble is being transmitted.

[0033] When a specific condition is met, such as when the number of in-area terminal devices 100 is less than a predetermined number, the base station device 200 disables the NES-compatible PRACH resource and transitions to a sleep state during period P1. This allows some monitoring to be stopped, thereby reducing power consumption.

[0034] For example, when the predetermined condition is no longer satisfied, the base station device 200 cancels the sleep state, returns to the active state, and starts monitoring again.

[0035] <Random Access Processing> A description will be given of the random access processing performed by the terminal device 100. Note that the random access processing is a series of processing up to reception of RAR or MsgB (message B), and the subsequent connection processing is assumed to be the same as conventional processing.

[0036] Furthermore, the base station device 200 combines multiple (one or more) PRACH resources and presents them to the terminal device 100 as a resource set. This set of PRACH resources may be called a Random Access (RA) resource set. The RA resource set includes, for example, an RO and a preamble. The RO is, for example, a time domain or / and frequency domain resource for transmitting a preamble. The RA resource set corresponds to, for example, various functions. A set of NES-compatible PRACH resources is referred to, for example, as an NES-compatible RA resource set.

[0037] The following describes an example in which there are three RA resource sets. The three resource sets are an NES-compatible RA resource set, a legacy RA resource set, and an other-function-compatible RA resource set. The legacy RA resource set is a resource set that does not correspond to any particular function and is also usable by the terminal device 101. The other-function-compatible RA resource set is usable by the terminal device 100 and terminal device 101 that correspond to other functions (other than the NES function).

[0038] Each RA resource set is notified, for example, by a system information update (SIB1) or RRC Reconfiguration. Furthermore, whether each RA resource set is valid (available) is notified, for example, by a MAC-CE (Medium Access Control Element) or DCI (Downlink Control Information). The contents and valid / invalid status of the RA resource set may be notified by any of SIB1, MAC-CE, or DCI, or may be notified by another message. Furthermore, the information may be shared in advance between the terminal device 100 and the base station device 200.

[0039] Furthermore, settings including priorities and rules for selecting one of the RA resource sets are notified, for example, from the base station device 200 to the terminal device 100. The terminal device 100 selects an RA resource set in accordance with the settings and performs random access.

[0040] For example, if the terminal device 100 is an NES-compatible terminal, and an NES-compatible RA resource set is notified and configured in either SIB1 or RRC, and is notified and enabled in either SIB1, MAC-CE, or DCI, the terminal device 100 determines that the NES-compatible RA resource set is available and selects it.

[0041] For example, if the terminal device 100 is not an NES-capable terminal, or if it is not configured by notification in either SIB1 or RRC, or if it is disabled by notification in either SIB1, MAC-CE, or DCI, or if the location where the terminal device 100 monitors DCI is configured but DCI cannot be detected, the terminal device 100 determines that an NES-capable RA resource set is unavailable. Furthermore, the terminal device 100 may determine that an NES-capable RA resource set is unavailable and select a legacy RA resource set. For example, if the terminal device 100 is an NES-capable terminal for multiple functions (e.g., NES function and other functions), and if an RA resource set corresponding to these multiple functions is available and there is only one, the terminal device 100 selects that RA resource set. Furthermore, if an RA resource set corresponding to these multiple functions is available and there are multiple, the terminal device 100 selects the RA resource set corresponding to the function with the highest priority based on the priority of the functions configured by the base station device 200.

[0042] <First Method> The first method of the random access process will be described below. Fig. 5 is a diagram showing an example of the random access process S100.

[0043] The terminal device 100 selects an RA resource set (S101). The RA resource set is selected in accordance with the above-described settings.

[0044] The terminal device 100 selects the next available RO within the selected RA resource set (S102).

[0045] The terminal device 100 transmits a preamble to the base station device 200 in the selected RO (S103). Note that in the subsequent processing flow, the preamble transmission processing S103 may also include the selection of a preamble. Furthermore, after transmitting the preamble to the base station device 200 in the selected RO, the terminal device 100 may transmit a signal in a PUSCH related to the selected RO.

[0046] For example, after a predetermined time has elapsed, the terminal device 100 checks whether or not an RAR (Random Access Response) or MsgB has been received (S104).

[0047] If the terminal device 100 receives an RAR or MsgB (Yes in S104), it continues the connection process (random access) (S112) and ends the process.

[0048] On the other hand, if the terminal device 100 fails to receive the RAR or MsgB (No in S104), it increments a counter (S105). The counter is cleared to 0 when the RA resource set is selected, and indicates the number of times reception of the RAR or MsgB has failed (the number of times the preamble has been retransmitted).

[0049] The terminal device 100 checks whether the selected RA resource set is NES compatible (S106).

[0050] If the selected RA resource set is not NES-compatible (No in S106), the terminal device 100 determines whether the counter exceeds a first threshold (S110). The first threshold indicates the number of retransmissions allowed before determining that the connection has failed (random access has failed).

[0051] If the counter does not exceed the first threshold value (No in S110), the terminal device 100 starts again from selecting an RO (S102).

[0052] On the other hand, if the counter exceeds the first threshold value (Yes in S110), the terminal device 100 determines that the connection has failed (S111) and ends the process.

[0053] On the other hand, if the selected RA resource set is NES-compatible (Yes in S106), the terminal device 100 determines whether the counter exceeds a second threshold (S107). The second threshold indicates the number of retransmissions permitted before determining that the connection has failed when the NES-compatible RA resource set is selected.

[0054] If the counter does not exceed the second threshold value (No in S107), the terminal device 100 starts again from selecting an RO (S102).

[0055] On the other hand, if the counter exceeds the second threshold (Yes in S107), the terminal device 100 determines that the connection has failed (S108), reacquires SIB1 (S109), and ends the processing. By reacquiring SIB1, the terminal device 100 can acquire the latest (updated) RA resource set (particularly, the NES-compatible RA resource set). Note that the terminal device 100 may reacquire DCI instead of or in addition to SIB1. By reacquiring DCI, it may be possible to determine the validity (whether or not the RA resource set is available) of the RA resource set.

[0056] 6 is a diagram showing an example of how the first method is reflected in the specifications. For example, Fig. 6 shows an example of "5.1.4 Random Access Response reception" in the 3GPP specifications "TS38.321." The underlined parts are the changed parts.

[0057] <Second Method> A second method of random access processing will now be described. Fig. 7 is a diagram showing an example of random access processing S200.

[0058] The terminal device 100 selects an RA resource set (S201). The selection of the RA resource set is performed in accordance with the settings described above.

[0059] The terminal device 100 selects the next available RO within the selected RA resource set (S202).

[0060] The terminal device 100 transmits a preamble to the base station device 200 in the selected RO (S203).

[0061] The terminal device 100 checks whether or not an RAR or MsgB has been received after a predetermined time has elapsed (S204).

[0062] If the terminal device 100 receives an RAR or MsgB (Yes in S204), it continues the connection process (random access) (S211) and ends the process.

[0063] On the other hand, if the terminal device 100 has not received the RAR or MsgB (No in S204), the terminal device 100 increments the counter (S205).

[0064] The terminal device 100 determines whether the counter exceeds a first threshold value (S206). The first threshold value indicates the number of retransmissions allowed before determining that the connection has failed (random access has failed).

[0065] If the counter exceeds the first threshold value (Yes in S206), the terminal device 100 determines that the connection has failed (S210) and ends the process.

[0066] On the other hand, if the counter does not exceed the first threshold (No in S206), the terminal device 100 checks whether "the selected RA resource set is NES-compatible and the counter exceeds the second threshold" (S207). The second threshold indicates the number of retransmissions allowed until it is determined that the connection has failed when an NES-compatible RA resource set is selected.

[0067] If the selected RA resource set is not NES compatible or the counter does not exceed the second threshold (No in S207), the terminal device 100 starts over from selecting an RO (S202).

[0068] If the selected RA resource set is NES-compatible and the counter exceeds the second threshold (Yes in S207), the terminal device 100 determines that the connection has failed (S208), reacquires SIB1 (S209), and terminates the processing. Note that the terminal device 100 may reacquire DCI instead of SIB1 or in addition to SIB1.

[0069] 8 is a diagram showing an example of how the second method is reflected in the specifications. For example, Fig. 8 shows an example of "5.1.4 Random Access Response reception" in the 3GPP specifications "TS38.321." The underlined parts are the changed parts.

[0070] <Third Method> A third method of random access processing will now be described. Fig. 9 is a diagram showing an example of random access processing S300.

[0071] The terminal device 100 selects an RA resource set (S301). The RA resource set is selected in accordance with the settings described above.

[0072] The terminal device 100 selects the next available RO within the selected RA resource set (S302).

[0073] The terminal device 100 transmits a preamble to the base station device 200 in the selected RO (S303).

[0074] The terminal device 100 checks whether or not an RAR or MsgB has been received after a predetermined time has elapsed (S304).

[0075] If the terminal device 100 receives an RAR or MsgB (Yes in S304), it continues the connection process (random access) (S308) and ends the process.

[0076] On the other hand, if the terminal device 100 has not received the RAR or MsgB (No in S304), it increments the counter (S305).

[0077] The terminal device 100 determines whether the counter exceeds the first threshold value (S306).

[0078] If the counter exceeds the first threshold value (Yes in S306), the terminal device 100 determines that the connection has failed (S307) and ends the process.

[0079] On the other hand, if the counter does not exceed the first threshold (No in S306), the terminal device 100 checks whether "the selected RA resource set is NES-compatible and the selected RA resource set is invalid" (S309). When performing random access processing, the validity / invalidity of the RA resource set may change due to, for example, reacquisition of DCI. Furthermore, the terminal device 100 may temporarily suspend the random access processing for a certain period of time, for example, by using a back-off timer. Before the back-off timer expires, SIB1 may be reacquired, or DCI may be reacquired instead of SIB1 or in addition to SIB1. The timer value of the back-off timer is set, for example, randomly.

[0080] If the selected RA resource set is not NES compatible or the selected RA resource set is valid (No in S309), the terminal device 100 starts again from selecting an RO (S302).

[0081] If the selected RA resource set is NES-compatible and the selected RA resource set is invalid (Yes in S309), the terminal device 100 changes the NES-compatible RA resource set to invalid (internally stores that the NES-compatible resource set is invalid) and starts over again, starting with selecting the RA resource set (S301).

[0082] <Fourth Method> A fourth method of random access processing will now be described. Fig. 10 is a diagram showing an example of random access processing S400.

[0083] The terminal device 100 selects an RA resource set (S401). The RA resource set is selected in accordance with the settings described above.

[0084] The terminal device 100 selects the next available RO within the selected RA resource set (S402).

[0085] The terminal device 100 transmits a preamble to the base station device 200 in the selected RO (S403).

[0086] The terminal device 100 checks whether or not an RAR or MsgB has been received after a predetermined time has elapsed (S404).

[0087] If the terminal device 100 receives an RAR or MsgB (Yes in S404), it continues the connection process (random access) (S411) and ends the process.

[0088] On the other hand, if the terminal device 100 has not received the RAR or MsgB (No in S404), it increments the counter (S405).

[0089] The terminal device 100 checks whether the selected RA resource set is NES compatible (S406).

[0090] If the selected RA resource set is not NES-compatible (No in S406), the terminal device 100 determines whether the counter exceeds the first threshold value (S409).

[0091] If the counter does not exceed the first threshold value (No in S409), the terminal device 100 starts again from selecting an RO (S402).

[0092] On the other hand, if the counter exceeds the first threshold value (Yes in S409), the terminal device 100 determines that the connection has failed (S410) and ends the process.

[0093] On the other hand, if the selected RA resource set is NES-compatible (Yes in S406), the terminal device 100 determines whether the counter exceeds a second threshold (S407). The second threshold indicates the number of retransmissions before reselecting an RA resource set when the NES-compatible RA resource set is selected.

[0094] If the counter does not exceed the second threshold value (No in S407), the terminal device 100 starts again from selecting an RO (S402).

[0095] On the other hand, if the counter exceeds the second threshold (Yes in S407), the terminal device 100 invalidates the NES-compatible RA resource set (stores it as invalid) and starts again from selecting an RA resource set (S401).

[0096] 11 is a diagram showing an example of how the fourth method is reflected in the specifications. Fig. 11 shows an example of "5.1.4 Random Access Response reception" in the 3GPP specifications "TS38.321." The underlined parts are the changed parts.

[0097] [Other Embodiments] The terminal device 100 may, for example, consider an NES-compatible RA resource set and a legacy RA resource set to be the same resource set. In other words, the terminal device 100 may select an NES-compatible RA resource set and a legacy RA resource set with the same priority. Fig. 12 is a diagram showing an example of reflection in a specification. Fig. 12 is, for example, an example of "5.1.1b Selection of the set of Random Access resources for the Random Access procedure" in the 3GPP specification "TS38.321." The underlined parts indicate the changes.

[0098] In addition, which of the methods to select may be instructed to the terminal device 100 by, for example, the base station device 200 or an even higher-level control device. In addition, which method to select may be set in advance and stored internally in the terminal device 100.

[0099] 10: Wireless communication system 100: Terminal device 101: Terminal device 110: CPU 120: Storage 121: Wireless communication program 122: Random access program 130: Memory 140: Antenna 150: Wireless communication circuit 200: Base station device 210: CPU 220: Storage 221: Wireless communication control program 222: PRACH adaptation program 2221: NES-compatible PRACH allocation module 2222: NES control module 230: Memory 240: Antenna 250: Wireless communication circuit

Claims

1. A terminal device corresponding to a first function, comprising: a control unit that, in a random access process, selects a random access resource list from a plurality of random access resource lists including one or more ROs (RACH Occasions) for transmitting a preamble, and selects an RO from the selected random access resource list; a transmitting unit that transmits the preamble using the selected RO; and a receiving unit that receives a response to the transmitted preamble, wherein the plurality of random access resource lists include a first random access resource list that can be used by a terminal device corresponding to the first function, and a second random access resource list that can be used by a terminal device corresponding to the first function and a terminal device that does not correspond to the first function.

2. The terminal device according to claim 1, wherein the control unit selects the first random access resource list and, when the number of retransmissions of the preamble exceeds a second threshold, acquires a message including information about the first random access resource list.

3. The terminal device according to claim 1, wherein the control unit selects the first random access resource list and, when the number of retransmissions of the preamble exceeds a second threshold, reselects a random access resource list from the second random access resource list.

4. The terminal device according to claim 1, wherein the control unit checks whether the first random access resource list is valid when the first random access resource list is selected and reception of the response fails.

5. The terminal device according to claim 4, wherein the control unit reselects a random access resource list from the second random access resource list when the first random access resource list is invalid.

6. The terminal device according to claim 1, wherein the control unit selects the first random access resource list and the second random access resource list with the same priority.

7. A base station device having a notification unit that notifies information regarding a first random access resource list including one or more ROs (RACH Occasions) for transmitting preambles in a random access process in a terminal device, the first random access resource list being usable by the terminal device corresponding to a first function, and a second random access resource list being usable by the terminal device corresponding to the first function and the terminal device not corresponding to the first function; a base station receiving unit that receives the preamble transmitted by the terminal device in the random access process; and a base station transmitting unit that transmits a response to the preamble to the terminal device.

8. A wireless communication system having a terminal device and a base station device, wherein the base station device, in a random access process of the terminal device, notifies information regarding a first random access resource list including one or more ROs (RACH Occasions) for transmitting a preamble, the first random access resource list being usable by the terminal device corresponding to a first function, and a second random access resource list being usable by the terminal device corresponding to the first function and the terminal device not corresponding to the first function; the terminal device receives the information, selects a random access resource list from a plurality of random access resource lists including the first random access resource list and the second random access resource list, selects an RO from the selected random access resource list, and transmits the preamble using the selected RO; the base station device receives the preamble and transmits a response to the preamble to the terminal device; and the terminal device receives the response.

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