Method and apparatus for determining bandwidth

Abstract

A method and apparatus for determining a bandwidth. The method comprises: when a maximum transmission bandwidth of a terminal is determined, the maximum transmission bandwidth of the terminal being associated with the type of the terminal, such that the maximum transmission bandwidth of the terminal matches the type of the terminal, and then a minimum protective bandwidth of the terminal matches the type of the terminal. In this way, the problems, such as the waste of frequency-domain resources and / or interference with other information transmitted in an adjacent frequency-domain resource, caused by setting the maximum transmission bandwidths and minimum protective bandwidths of all types of terminals to be fixed values for one channel bandwidth can be solved.

Description

Method and device for determining bandwidth

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of the People's Republic of China on August 31, 2023, with application number 202311137193.0 and invention name "A method and device for determining bandwidth", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The embodiments of the present application relate to the field of communication technologies, and in particular to a method and apparatus for determining bandwidth. Background Art

[0004] In new radio (NR) and long-term evolution (LTE) systems, the maximum transmission bandwidth and minimum guard bandwidth defined within the terminal's channel bandwidth are fixed values. For example, for narrowband-internet of things (NB-IoT) terminals in LTE, the terminal's channel bandwidth is defined as 200kHz. Within this 200kHz channel bandwidth, the protocol defines a maximum transmission bandwidth of 180kHz for the terminal, and defines a minimum guard bandwidth of 10kHz on each side of the maximum transmission bandwidth.

[0005] For the ambient IoT (A-IoT) terminals that will be introduced in NR, different types of A-IoT terminals have different requirements for frequency error tolerance. For example, for a backscatter-based A-IoT terminal, when the signal transmission bandwidth is approximately 180kHz, the maximum frequency error it can tolerate is 7% of the signal transmission bandwidth, and the maximum frequency error that can be tolerated is approximately 10 to 15kHz. For active A-IoT terminals, the maximum frequency error they can tolerate is approximately 5 to 10 parts per million (ppm), which is much larger than the maximum frequency error tolerated by traditional NR active terminals of 0.1ppm. Therefore, at a carrier center frequency of 900MHz, the frequency deviation tolerance of active terminals is 9kHz (900MHz * 10ppm). Because different types of A-IoT terminals have different frequency deviation tolerances and frequency offset correction capabilities, they require different minimum protection bandwidths, and furthermore, different maximum transmission bandwidths within the channel bandwidth. How to configure corresponding maximum transmission bandwidths for different types of A-IoT terminals to achieve maximum transmission efficiency for each type of A-IoT terminal is an urgent problem to be solved.

[0006] Summary of the Invention

[0007] Embodiments of the present application provide a method and apparatus for determining bandwidth to determine the maximum transmission bandwidth of different types of terminals.

[0008] In a first aspect, a method for determining bandwidth is provided, wherein the executor of the method is a terminal, or a unit in the terminal (such as a chip or circuit, etc.), including: determining the maximum transmission bandwidth of the terminal under a first channel bandwidth and a first subcarrier spacing, wherein the maximum transmission bandwidth of the terminal is associated with the type of the terminal under the first channel bandwidth and the first subcarrier spacing, and the first channel bandwidth includes a maximum transmission bandwidth and a minimum protection bandwidth; and performing signal transmission with an access network device based on the maximum transmission bandwidth of the terminal.

[0009] It can be understood that in the description of this article, for a terminal capable of generating an uplink carrier signal, its frequency error is a carrier frequency error, while for a terminal capable of reflecting a downlink carrier signal but not generating an uplink carrier signal, its frequency error is a signal frequency error.

[0010] In the description of this article, a terminal that has the ability to reflect downlink carrier signals but does not have the ability to generate uplink carrier signals can also be referred to as a terminal that only has the ability to reflect downlink carrier signals, a terminal that does not have the ability to generate uplink carrier signals, a terminal that does not have the ability to generate uplink carrier signals, or a terminal that only has backscattering capability.

[0011] In the description herein, a terminal capable of generating an uplink carrier signal may also be referred to as a terminal capable of generating an uplink carrier signal.

[0012] The above design allows different types of terminals to tolerate different maximum frequency errors. Based on the terminal type, a maximum transmission bandwidth is determined that matches the maximum frequency error tolerance requirement. For example, terminals with looser maximum frequency error requirements (i.e., larger maximum frequency error values) require a larger minimum protection bandwidth and a smaller maximum transmission bandwidth. Consequently, the terminal's frequency error calibration capability is weaker. Terminals with stricter maximum frequency error tolerance requirements (i.e., smaller maximum frequency error values) require a smaller minimum protection bandwidth and a larger maximum transmission bandwidth. Consequently, the terminal's frequency error calibration capability is stronger.

[0013] In one design, the terminal types include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not generating an uplink carrier signal (e.g., a backscatter terminal). Furthermore, the terminals capable of generating an uplink carrier signal include terminals with a maximum frequency error equal to X (e.g., a traditional terminal) and terminals with a maximum frequency error greater than X (e.g., an active A-IoT terminal). X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm).

[0014] Optionally, a terminal capable of generating an uplink carrier signal has stricter requirements on the maximum value of the frequency error than a terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal. Therefore, under the same terminal channel bandwidth and subcarrier spacing, the maximum transmission bandwidth corresponding to the terminal capable of generating an uplink carrier signal is greater than the maximum transmission bandwidth corresponding to the terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal.

[0015] Through the above design, different maximum transmission bandwidth configurations are defined for different types of A-IoT terminals under the same channel bandwidth, enabling A-IoT terminals of each type or capability to maximize their transmission efficiency and minimize the interference of signal transmission caused by frequency error on the transmission of other terminals.

[0016] Optionally, a smaller maximum frequency error value indicates a stronger frequency offset calibration capability, and a larger transmission bandwidth is required. Therefore, in one design, for terminals capable of generating uplink carriers, the maximum transmission bandwidth corresponding to a terminal with a maximum frequency error value equal to X is greater than the maximum transmission bandwidth corresponding to a terminal with a maximum frequency error value greater than X.

[0017] In one design, the maximum transmission bandwidth of the terminal includes a maximum downlink transmission bandwidth of the terminal and a maximum uplink transmission bandwidth of the terminal, and the maximum uplink transmission bandwidth of the terminal is greater than the maximum downlink transmission bandwidth of the terminal.

[0018] With the above design, when a terminal accesses the network, it first receives a downlink signal, which can be a synchronization signal or other broadcast signal. After receiving the downlink signal, the terminal can perform frequency error calibration based on the downlink signal. This frequency error calibration reduces the maximum frequency error of the terminal, thereby supporting a larger maximum transmission bandwidth for the uplink than for the downlink. In this design, the uplink maximum transmission bandwidth is greater than the downlink maximum transmission bandwidth, which improves uplink resource utilization compared to configuring the uplink and downlink maximum transmission bandwidths to be the same.

[0019] The second aspect is the opposite end corresponding to the first aspect. The beneficial effects can be found in the description of the first aspect. A method for determining bandwidth is provided. The execution subject of the method is an access network device, or a unit (chip or circuit, etc.) in the access network device, including: determining the maximum transmission bandwidth of the terminal under the first channel bandwidth and the first subcarrier spacing. Under the first channel bandwidth and the first subcarrier spacing, the maximum transmission bandwidth of the terminal is associated with the type of the terminal, and the first channel bandwidth includes the maximum transmission bandwidth and the minimum protection bandwidth; and transmitting signals with the terminal according to the maximum transmission bandwidth of the terminal.

[0020] In one design, the terminal types include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal. Furthermore, the terminals capable of generating an uplink carrier signal include terminals having a maximum frequency error equal to X, and terminals having a maximum frequency error greater than X. X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm).

[0021] In one design, the maximum transmission bandwidth for terminals capable of generating uplink carrier signals is greater than the maximum transmission bandwidth for terminals capable of reflecting downlink carrier signals but not generating uplink carrier signals. Different maximum transmission bandwidth configurations are defined for different types of A-IoT terminals within the same channel bandwidth. This allows each type or capability of A-IoT terminal to maximize its transmission efficiency while avoiding interference with other terminals caused by frequency errors.

[0022] In one design, the maximum transmission bandwidth corresponding to a terminal whose maximum frequency error is equal to X is greater than the maximum transmission bandwidth corresponding to a terminal whose maximum frequency error is greater than X.

[0023] In one design, the maximum transmission bandwidth of the terminal includes a maximum downlink transmission bandwidth of the terminal and a maximum uplink transmission bandwidth of the terminal, and the maximum uplink transmission bandwidth of the terminal is greater than the maximum downlink transmission bandwidth of the terminal.

[0024] In one design, the maximum transmission bandwidth and minimum guard bandwidth of a terminal are associated with the frequency band in which the terminal resides. Higher frequencies in the frequency band correspond to smaller maximum transmission bandwidth and larger minimum guard bandwidth. Optionally, the minimum guard bandwidth is proportional to the carrier frequency, carrier center frequency, band start frequency, or band cutoff frequency.

[0025] According to a third aspect, a method for determining bandwidth is provided, wherein the execution subject of the method is a terminal, or a unit (chip or circuit, etc.) in the terminal, and the method includes: sending a first uplink signal to an access network device on a first uplink channel; sending a second uplink signal to the access network device on a second uplink channel, wherein the maximum signal bandwidth of the second uplink signal is greater than the maximum signal bandwidth of the first uplink signal.

[0026] Optionally, the maximum signal bandwidth may also be referred to as a configurable maximum signal bandwidth, a configurable maximum signal bandwidth, an indicative maximum signal bandwidth, or an indicative maximum signal bandwidth. Furthermore, the maximum signal bandwidth may also be referred to as the maximum signal bandwidth in a set of configurable maximum signal bandwidths or the maximum signal bandwidth in a set of indicative maximum signal bandwidths.

[0027] Optionally, the modulation mode of the first uplink signal and the second uplink signal may be on-off keying (OOK), amplitude shift keying (ASK), frequency shift keying (FSK), or binary phase shift keying (BPSK) modulation.

[0028] The above design allows different uplink signal configurations to have different maximum signal bandwidths. For example, a terminal may first transmit a first uplink signal and then a second uplink signal. The maximum signal bandwidth of the second uplink signal configuration is greater than the maximum signal bandwidth of the first uplink signal configuration. This design, compared to a design where the maximum signal bandwidth of the second uplink signal configuration is the same as the maximum signal bandwidth of the first uplink signal configuration, improves transmission efficiency and frequency domain resource utilization for uplink transmissions of different uplink signals, across different uplink channels, and at different uplink transmission stages.

[0029] In one design, the maximum value of the frequency error of the first uplink signal is a first value, the maximum value of the frequency error of the second uplink signal is a second value, and the second value is smaller than the first value.

[0030] In one design, the method further includes: receiving a first downlink signal from an access network device on a first downlink channel, the first downlink signal including frequency adjustment information; sending a second uplink signal to the access network device on a second uplink channel, for example, including: performing frequency adjustment based on the frequency adjustment information; and sending the second uplink signal to the access network device on the second uplink channel.

[0031] In one design, the first uplink signal is a signal carrying message 1 in the random access procedure, and the second uplink signal is a signal carrying message 3 or a signal subsequent to message 3 in the random access procedure. The first uplink channel is a physical random access channel (PRACH), and the second uplink channel is a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH).

[0032] Through the above design, the frequency correction is performed by using the signal in the first step PRACH of random access as a reference signal, which can further improve the transmission efficiency and frequency domain resource utilization of subsequent message 3 and subsequent data transmission.

[0033] In one design, the first uplink signal is a signal carrying message 3 in the random access process, and the second uplink signal is a signal subsequent to message 3, such as an uplink signal carrying a positive acknowledgement (ACK) or negative acknowledgement (NACK) of message 4, or an uplink signal carrying message 5. The first uplink channel is a physical uplink shared channel (PUSCH). When the second uplink signal is an uplink signal carrying message 4, the second uplink channel is a physical uplink control channel (PUCCH). When the second uplink signal is an uplink signal carrying message 5, the second uplink channel is a physical uplink shared channel (PUSCH).

[0034] In the above design, by adjusting the frequency of short message transmission during random access, the transmission efficiency and frequency domain resource utilization can be further improved when uplink signals with longer signal durations are subsequently transmitted.

[0035] In one design, the first uplink signal is a synchronization signal or a reference signal, and the second uplink signal is a signal carrying uplink data information or a signal carrying uplink control information. The synchronization signal or reference signal is a synchronization signal or a reference signal of the second uplink signal, or can be said to be associated with the second uplink signal, and the synchronization signal or reference signal is used for time synchronization between the access network device and the terminal. The first uplink channel is the PUSCH, and the second uplink channel is the PUSCH or the PUCCH.

[0036] Through the above design, by detecting and adjusting the frequency of the reference signal or synchronization signal with a shorter transmission time, the transmission efficiency and frequency domain resource utilization can be further improved when the uplink data signal with a longer transmission time is subsequently transmitted.

[0037] In one design, the further step includes determining, based on the type of the terminal, a maximum signal bandwidth of the first uplink signal and a maximum signal bandwidth of the second uplink signal of the terminal. For example, based on the type of the terminal, the maximum transmission bandwidth of the terminal is determined, and the maximum signal bandwidth of the first uplink signal and the maximum signal bandwidth of the second uplink signal are less than or equal to the maximum transmission bandwidth of the terminal.

[0038] In one design, the terminal types include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal. Furthermore, the terminals capable of generating an uplink carrier signal include terminals having a maximum frequency error equal to X, and terminals having a maximum frequency error greater than X. X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm).

[0039] In one design, it also includes: sending a message to the access network device, where the message includes the type of terminal.

[0040] The fourth aspect is the counterpart corresponding to the third aspect. The beneficial effects can be found in the description of the third aspect. A method for determining bandwidth is provided. The executor of the method is an access network device, or a unit (module or circuit, etc.) in the access network device, including: receiving a first uplink signal from the terminal on a first uplink channel; receiving a second uplink signal from the terminal on a second uplink channel, and the maximum signal bandwidth of the second uplink signal is greater than the maximum signal bandwidth of the first uplink signal.

[0041] Optionally, the maximum signal bandwidth may also be referred to as a configurable maximum signal bandwidth, a configurable maximum signal bandwidth, an indicative maximum signal bandwidth, or an indicative maximum signal bandwidth. Furthermore, the maximum signal bandwidth may also be referred to as the maximum signal bandwidth in a set of configurable maximum signal bandwidths or the maximum signal bandwidth in a set of indicative maximum signal bandwidths.

[0042] Optionally, the modulation mode of the first uplink signal and the second uplink signal may be on-off keying (OOK), amplitude shift keying (ASK), frequency shift keying (FSK), or binary phase shift keying (BPSK) modulation.

[0043] In one design, the maximum value of the frequency error of the first uplink signal is a first value, the maximum value of the frequency error of the second uplink signal is a second value, and the second value is smaller than the first value.

[0044] In one design, the method further includes sending a first downlink signal to the terminal on a first downlink channel, where the first downlink signal includes frequency adjustment information.

[0045] In one design, the first uplink signal is a signal carrying message 1 in the random access procedure, and the second uplink signal is a signal carrying message 3 or a signal subsequent to message 3 in the random access procedure. The first uplink channel is a physical random access channel (PRACH), and the second uplink channel is a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH).

[0046] In one design, the first uplink signal is a signal carrying message 3 in the random access process, and the second uplink signal is a signal subsequent to message 3, such as an uplink signal carrying a positive acknowledgement (ACK) or negative acknowledgement (NACK) of message 4, or an uplink signal carrying message 5. The first uplink channel is a physical uplink shared channel (PUSCH). When the second uplink signal is an uplink signal carrying message 4, the second uplink channel is a physical uplink control channel (PUCCH). When the second uplink signal is an uplink signal carrying message 5, the second uplink channel is a physical uplink shared channel (PUCCH).

[0047] In one design, the first uplink signal is a synchronization signal or a reference signal, and the second uplink signal is a signal carrying uplink data information or a signal carrying uplink control information. The synchronization signal or reference signal is a synchronization signal or a reference signal of the second uplink signal, or can be said to be associated with the second uplink signal, and the synchronization signal or reference signal is used for time synchronization between the access network device and the terminal. The first uplink channel is the PUSCH, and the second uplink channel is the PUSCH or the PUCCH.

[0048] In one design, the further step includes determining, based on the type of the terminal, a maximum signal bandwidth of the first uplink signal and a maximum signal bandwidth of the second uplink signal of the terminal. For example, based on the type of the terminal, the maximum transmission bandwidth of the terminal is determined, and the maximum signal bandwidth of the first uplink signal and the maximum signal bandwidth of the second uplink signal are less than or equal to the maximum transmission bandwidth of the terminal.

[0049] In one design, the terminal types include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal. Furthermore, the terminals capable of generating an uplink carrier signal include terminals having a maximum frequency error equal to X, and terminals having a maximum frequency error greater than X. X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm).

[0050] In one design, the method further includes receiving a message from a terminal, where the message includes the type of the terminal.

[0051] In a fifth aspect, a method for determining bandwidth is provided, wherein the executor of the method is a terminal, or a unit (chip or circuit, etc.) in the terminal, including: receiving a first downlink signal from an access network device on a first downlink channel; receiving a second downlink signal from an access network device on a second downlink channel, wherein the maximum signal bandwidth of the second downlink signal is greater than the maximum signal bandwidth of the first downlink signal.

[0052] Optionally, the modulation mode of the first downlink signal and the second downlink signal is on-off keying (OOK), amplitude shift keying (ASK), or frequency shift keying (FSK) modulation.

[0053] Through the above design, the maximum signal bandwidth configured for different downlink signals is not the same. For example, the access network device first sends the first downlink signal to the terminal. Since the terminal can adjust the frequency according to the first downlink signal when receiving the first downlink signal, the maximum value of the frequency error of the terminal will become smaller. Therefore, the second downlink signal sent by the access network device to the terminal can support a larger maximum signal bandwidth. Compared with configuring the same maximum signal bandwidth for downlink signals, the transmission efficiency and frequency domain resource utilization of different downlink transmission stages, different downlink channels, and different downlink signals can be improved. In particular, when the downlink uses a low-power, low-spectral-efficiency modulation method, increasing the effective signal bandwidth can more effectively improve the transmission efficiency.

[0054] In one design, the maximum value of the frequency error of the first downlink signal is a first value, the maximum value of the frequency error of the second downlink signal is a second value, and the second value is smaller than the first value.

[0055] In one design, it also includes: the terminal performing frequency correction according to the first downlink signal.

[0056] In one design, the first downlink signal is used for at least one of time synchronization, frequency synchronization, or system information, and the second downlink signal includes a signal carrying downlink data information or a signal carrying downlink control information. The first downlink channel includes a physical broadcast channel (PBCH), and the second downlink channel includes a physical downlink shared channel (PDSCH) or a physical downlink control channel (PDCCH).

[0057] Under the above design, by calibrating the frequency error of the existing public signal that can be used for periodic transmission, the transmission efficiency and frequency domain resource utilization can be further improved when the downlink data signal and control signal are subsequently transmitted.

[0058] In one design, the first downlink signal is a synchronization signal or reference signal used for time synchronization between the terminal and access network equipment. The second downlink signal carries downlink data information or downlink control information. The synchronization signal or reference signal is a synchronization signal or reference signal for the second downlink signal. The first downlink channel is the PDSCH, and the second downlink channel is the PDSCH or PDCCH.

[0059] In the above design, by calibrating the frequency error of the existing common frequency that can be used to send along with the data signal, the transmission efficiency and frequency domain resource utilization can be further improved when the downlink data signal and control signal are subsequently sent.

[0060] In one design, the further step includes determining, based on the type of the terminal, a maximum signal bandwidth of the first downlink signal and a maximum signal bandwidth of the second downlink signal of the terminal. For example, based on the type of the terminal, the maximum transmission bandwidth of the terminal is determined, and the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal are less than or equal to the maximum transmission bandwidth of the terminal.

[0061] In one design, the terminal types include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal. Furthermore, the terminals capable of generating an uplink carrier signal include terminals having a maximum frequency error equal to X, and terminals having a maximum frequency error greater than X. X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm).

[0062] In one design, it also includes: sending a message to the access network device, where the message includes the type of terminal.

[0063] The sixth aspect is the counterpart corresponding to the fifth aspect. The beneficial effects can be found in the description of the fifth aspect. A method for determining bandwidth is provided. The execution subject of the method is an access network device, or a unit (chip or circuit, etc.) in the access network device, including: sending a first downlink signal to the terminal on a first downlink channel; sending a second downlink signal to the terminal on a second downlink channel, and the maximum signal bandwidth of the second downlink signal is greater than the maximum signal bandwidth of the first downlink signal.

[0064] Optionally, the modulation mode of the first downlink signal and the second downlink signal is on-off keying (OOK), amplitude shift keying (ASK), or frequency shift keying (FSK) modulation.

[0065] In one design, the maximum value of the frequency error of the first downlink signal is a first value, the maximum value of the frequency error of the second downlink signal is a second value, and the second value is smaller than the first value.

[0066] In one design, the modulation mode of the first downlink signal and the second downlink signal is on-off keying (OOK), amplitude shift keying (ASK), or frequency shift keying (FSK) modulation.

[0067] In one design, the first downlink signal is used for at least one of time synchronization, frequency synchronization, or system information, and the second downlink signal includes a signal carrying downlink data information or a signal carrying downlink control information. The first downlink channel includes a physical broadcast channel (PBCH), and the second downlink channel includes a physical downlink shared channel (PDSCH) or a physical downlink control channel (PDCCH).

[0068] In one design, the first downlink signal is a synchronization signal or a reference signal, and the synchronization signal or reference signal is used for time synchronization between the terminal and the access network device. The second downlink signal is a signal that carries downlink data information or carries downlink control information. The synchronization signal or reference signal is a synchronization signal or a reference signal of the second downlink signal. The first downlink channel is the PDSCH, and the second downlink channel is the PDSCH or the PDCCH. In one design, the further step includes: determining the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal of the terminal based on the type of the terminal. For example, the maximum transmission bandwidth of the terminal is determined based on the type of the terminal, and the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal are less than or equal to the maximum transmission bandwidth of the terminal.

[0069] In one design, the terminal types include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal. Furthermore, the terminals capable of generating an uplink carrier signal include terminals having a maximum frequency error equal to X, and terminals having a maximum frequency error greater than X. X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm).

[0070] In one design, the method further includes receiving a message from a terminal, where the message includes the type of the terminal.

[0071] In the seventh aspect, a method for determining bandwidth is provided, wherein the executor of the method is a terminal, or a unit (chip or circuit, etc.) in the terminal, including: receiving a first downlink signal from an access network device on a first downlink channel; sending a first uplink signal to the access network device on a first uplink channel; the maximum signal bandwidth of the first uplink signal is greater than the maximum signal bandwidth of the first downlink signal.

[0072] Optionally, the modulation mode of the first downlink signal is on-off keying (OOK), amplitude shift keying (ASK), or frequency shift keying (FSK). The modulation mode of the first uplink signal is on-off keying (OOK), amplitude shift keying (ASK), frequency shift keying (FSK), or binary phase shift keying (BPSK).

[0073] The above design allows uplink and downlink signals to be configured with different maximum signal bandwidths. For example, the uplink maximum signal bandwidth is larger than the downlink maximum signal bandwidth. This improves uplink signal transmission efficiency and frequency domain resource utilization compared to configuring the same maximum signal bandwidth for both uplink and downlink signals.

[0074] In one design, the maximum value of the frequency error of the first downlink signal is a first value, the maximum value of the frequency error of the first uplink signal is a second value, and the second value is smaller than the first value.

[0075] In one design, the method further includes performing frequency correction based on the first downlink signal.

[0076] In one design, the first downlink signal is a synchronization signal, a signal carrying a system message, a downlink data signal, or a downlink control signal, and the first uplink signal can be a random access preamble, an uplink data signal, or an uplink control signal. Optionally, the first downlink channel can be a PBCH, a PDCCH, or a PDSCH, and the first uplink channel can be a PRACH, a PUSCH, or a PUCCH.

[0077] In one design, the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the first uplink signal may be determined based on the type of the terminal. For example, in one implementation, the maximum transmission bandwidth of the terminal may be determined based on the type of the terminal. The maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the first uplink signal are less than or equal to the maximum transmission bandwidth of the terminal.

[0078] In one design, the terminal types include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal. Furthermore, the terminals capable of generating an uplink carrier signal include terminals having a maximum frequency error equal to X, and terminals having a maximum frequency error greater than X. X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm).

[0079] In one design, it also includes: sending a message to the access network device, where the message includes the type of terminal.

[0080] In an eighth aspect, for the counterpart corresponding to the seventh aspect, the beneficial effects of which can be found in the description of the seventh aspect, a method for determining bandwidth is provided. The method is performed by an access network device, or a unit (chip or circuit, etc.) in the access network device, comprising: sending a first downlink signal to a terminal on a first downlink channel. Receiving a first uplink signal from the terminal on a first uplink channel. The maximum signal bandwidth corresponding to the first uplink signal is greater than the maximum signal bandwidth corresponding to the first downlink signal.

[0081] Optionally, the modulation mode of the first downlink signal is on-off keying (OOK), amplitude shift keying (ASK), or frequency shift keying (FSK). The modulation mode of the first uplink signal is on-off keying (OOK), amplitude shift keying (ASK), frequency shift keying (FSK), or binary phase shift keying (BPSK).

[0082] In one design, the maximum value of the frequency error of the first downlink signal is a first value, the maximum value of the frequency error of the first uplink signal is a second value, and the second value is smaller than the first value.

[0083] In one design, the first downlink signal is a synchronization signal, a signal carrying a system message, a downlink data signal, or a downlink control signal, and the first uplink signal can be a random access preamble, an uplink data signal, or an uplink control signal. Optionally, the first downlink channel can be a PBCH, a PDCCH, or a PDSCH, and the first uplink channel can be a PRACH, a PUSCH, or a PUCCH.

[0084] In one design, the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the first uplink signal may be determined based on the type of the terminal. For example, in one implementation, the maximum transmission bandwidth of the terminal may be determined based on the type of the terminal. The maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the first uplink signal are less than or equal to the maximum transmission bandwidth of the terminal.

[0085] In one design, the terminal types include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not capable of generating an uplink carrier signal. Furthermore, the terminals capable of generating an uplink carrier signal include terminals having a maximum frequency error equal to X, and terminals having a maximum frequency error greater than X. X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm).

[0086] In one design, the method further includes: receiving a message from a terminal, where the message includes the type of the terminal.

[0087] In a ninth aspect, a device is provided that can implement the method of the first, third, fifth, or seventh aspect. For example, the device includes means for executing the corresponding method of the first, third, fifth, or seventh aspect. The device can be implemented through hardware, software, or hardware executing the corresponding software implementation.

[0088] In one design, the apparatus includes a unit that performs the first, third, fifth, or seventh aspects described above.

[0089] In one design, the apparatus includes a processor configured to execute the method of the first, third, fifth, or seventh aspect described above.

[0090] In one design, the device includes a processor and an interface circuit, the interface circuit is used to receive signals from other devices outside the device and transmit them to the processor or send signals from the processor to other devices outside the device, and the processor is used to implement the methods of the above-mentioned first aspect, third aspect, fifth aspect or seventh aspect through logic circuits or executing code instructions.

[0091] In one design, the device includes a processor and a memory, and the processor is used to execute a computer program or instructions stored in the memory, so that the device implements the method of the first aspect, the third aspect, the fifth aspect or the seventh aspect above.

[0092] In a tenth aspect, a device is provided that can implement the method of the second, fourth, sixth, or eighth aspects. For example, the device includes means for executing the corresponding method of the second, fourth, sixth, or eighth aspects. The device can be implemented through hardware, software, or hardware executing the corresponding software implementation.

[0093] In one design, the apparatus includes a unit for performing the second, fourth, sixth, or eighth aspects described above.

[0094] In one design, the apparatus includes a processor configured to execute the method of the second, fourth, sixth, or eighth aspect described above.

[0095] In one design, the device includes a processor and an interface circuit, the interface circuit is used to receive signals from other devices outside the device and transmit them to the processor or send signals from the processor to other devices outside the device, and the processor is used to implement the methods of the second, fourth, sixth or eighth aspects above through logic circuits or execution code instructions.

[0096] In one design, the device includes a processor and a memory, and the processor is used to execute a computer program or instructions stored in the memory, so that the device implements the method of the second aspect, fourth aspect, sixth aspect or eighth aspect above.

[0097] In the eleventh aspect, a computer-readable storage medium is provided, which stores a computer program or instruction. When the computer program or instruction is executed on a computer, the computer implements the method of any one of the first to eighth aspects above.

[0098] In the twelfth aspect, a computer program product is provided, comprising a computer program or instructions, which, when executed by a computer, enables the method of any one of the above-mentioned first to eighth aspects to be executed.

[0099] In the thirteenth aspect, a chip is provided, comprising a processor, wherein the processor is coupled to a memory and is used to execute a computer program or instruction stored in the memory, so that the chip implements the method of any one of the above-mentioned first to eighth aspects.

[0100] In the fourteenth aspect, a communication system is provided, comprising: a first device and a second device; wherein the first device is used to implement the method of the first aspect above, and the second device is used to implement the method of the second aspect above; or, the first device is used to implement the method of the third aspect above, and the second device is used to implement the method of the fourth aspect above; or, the first device is used to implement the method of the fifth aspect above, and the second device is used to implement the method of the sixth aspect above; or, the first device is used to implement the method of the seventh aspect above, and the second device is used to implement the method of the eighth aspect above. BRIEF DESCRIPTION OF THE DRAWINGS

[0101] FIG1 is a schematic diagram of a communication system provided in an embodiment of the present application;

[0102] FIG2 is a schematic diagram of a process provided in an embodiment of the present application;

[0103] FIG3 is another schematic diagram of the process provided in an embodiment of the present application;

[0104] FIG4 is another schematic diagram of the process provided in an embodiment of the present application;

[0105] FIG5 is another schematic diagram of the process provided in an embodiment of the present application;

[0106] FIG6 is a schematic structural diagram of a device provided in an embodiment of the present application;

[0107] FIG7 is another schematic diagram of the structure of the device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0108] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the embodiments of the present application will be further described in detail with reference to the accompanying drawings. The specific operation methods and functional descriptions in the method embodiments can also be applied to the device embodiments or system embodiments.

[0109] Figure 1 shows a possible, non-limiting system diagram. As shown in Figure 1 , a communication system 10 includes a radio access network (RAN) 100 and a core network (CN) 200. Optionally, the Internet 300 is also included.

[0110] The RAN 100 includes at least one RAN node (e.g., 110a and 110b in FIG. 1 , collectively referred to as 110) and at least one terminal (e.g., 120a to 120j in FIG. 1 , collectively referred to as 120). The RAN 100 may also include other RAN nodes, such as wireless relay equipment and / or wireless backhaul equipment (not shown in FIG. 1).

[0111] Terminal 120 can be connected to RAN node 110 wirelessly. RAN node 110 is connected to core network 200 wirelessly or by wire. The core network device in core network 200 and RAN node 110 in RAN 100 can be different physical devices, or they can be a single physical device that integrates the logical functions of the core network device and the logical functions of the radio access network.

[0112] RAN 100 may be a cellular system related to the Third Generation Partnership Project (3GPP), such as a fourth generation (4G) mobile communication system, a fifth generation (5G) mobile communication system, or a future-oriented evolution system, such as a sixth generation (6G) mobile communication system. RAN 100 may also be an open access network (O-RAN or ORAN), a cloud radio access network (CRAN), or a wireless fidelity (WiFi) system. RAN 100 may also be a communication system that integrates two or more of the above systems.

[0113] The RAN node 110, sometimes also referred to as access network equipment, RAN entity, or access node, constitutes part of the communication system and facilitates wireless access for terminals. In the subsequent description of this application, unless otherwise specified, the term "access network equipment" is used. Multiple RAN nodes 110 in the communication system 10 can be of the same type or different types. In some scenarios, the roles of the RAN node 110 and the terminal 120 are relative. For example, network element 120i in Figure 1 can be a helicopter or drone, which can be configured as a mobile base station. For terminals 120j accessing the RAN 100 via network element 120i, network element 120i is a base station; however, for base station 110a, network element 120i is a terminal. RAN nodes 110 and terminals 120 are sometimes referred to as communication devices. For example, network elements 110a and 110b in Figure 1 can be understood as communication devices with base station functionality, and network elements 120a-120j can be understood as communication devices with terminal functionality.

[0114] In one possible scenario, a RAN node may be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next generation NodeB (gNB), a next generation base station in a 6G mobile communication system, a base station in a future mobile communication system, or an access node in a WiFi system. A RAN node may be a macro base station (such as 110a in FIG1 ), a micro base station or an indoor station (such as 110b in FIG1 ), a relay node or a donor node, or a wireless controller in a CRAN scenario. Optionally, a RAN node may also be a server, a wearable device, a vehicle or an onboard device. For example, an access network device in vehicle to everything (V2X) technology may be a road side unit (RSU). All or part of the functions of the RAN node in the embodiments of the present application may also be implemented by software functions running on hardware, or by virtualized functions instantiated on a platform (such as a cloud platform). The RAN node in the embodiments of the present application may also be a logical node, a logical module, or software that can implement all or part of the functions of the RAN node.

[0115] In another possible scenario, multiple RAN nodes collaborate to assist the terminal in achieving wireless access, and different RAN nodes respectively implement part of the functions of the base station. For example, the RAN node can be a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). The CU and DU can be set separately, or they can be included in the same network element, such as a baseband unit (BBU). The RU can be included in a radio frequency device or radio frequency unit, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH).

[0116] In different systems, CU (or CU-CP and CU-UP), DU or RU may also have different names, but those skilled in the art can understand their meanings. For example, in the ORAN system, CU may also be called O-CU (Open CU), DU may also be called O-DU, CU-CP may also be called O-CU-CP, CU-UP may also be called O-CU-UP, and RU may also be called O-RU. For the convenience of description, this application uses CU, CU-CP, CU-UP, DU and RU as examples for description. Any unit of CU (or CU-CP, CU-UP), DU and RU in this application can be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0117] A terminal may also be referred to as a terminal device, user equipment (UE), tag, mobile station, mobile terminal, etc. Terminals can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IOT), virtual reality (VR), augmented reality (AR), industrial control, autonomous driving, telemedicine, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, etc. The terminal can be a mobile phone, a head-mounted display device, a tablet computer, a computer with wireless transceiver function, a wearable device, a vehicle, a drone, a helicopter, an airplane, a ship, a robot, a robotic arm, a smart home device, etc. The embodiments of the present application do not limit the device form of the terminal.

[0118] In one design, a fixed maximum transmission bandwidth and minimum guard-band (GB) are defined within the channel bandwidth of the terminal. The channel bandwidth of the terminal can be referred to as the first channel bandwidth. For example, the first channel bandwidth of the terminal is 200kHz. Within the 200kHz first channel bandwidth, a fixed maximum transmission bandwidth of 180kHz and a fixed minimum guard-band of 10kHz are defined. For example, a minimum guard-band of 10kHz is left on each side of the maximum transmission bandwidth of 180kHz. There are many types of terminals, and different types of terminals have different maximum tolerance requirements for frequency error. Within a certain channel bandwidth, setting the maximum transmission bandwidth and minimum guard-band configuration of all types of terminals to fixed values ​​has various disadvantages. For example, for terminals with looser requirements for maximum frequency error (i.e., the maximum value of the frequency error is larger), it is necessary to configure a larger minimum protection bandwidth and a smaller maximum transmission bandwidth. Accordingly, the terminal has a poor ability to calibrate the frequency error. If the maximum transmission bandwidth and the minimum protection bandwidth of all types of terminals are set to fixed values, then for terminals with poor frequency deviation calibration capabilities, some transmitted signals may not meet the requirements, causing interference to the transmission of other information in adjacent frequency domain resources, affecting the system transmission performance. For terminals with stricter requirements for maximum frequency error tolerance (i.e., the maximum value of the frequency error is smaller), it is necessary to configure a smaller minimum protection bandwidth and a larger maximum transmission bandwidth. Accordingly, the terminal has a stronger ability to calibrate the frequency error. If the maximum transmission bandwidth and the minimum protection bandwidth of all types of terminals are set to fixed values, it may result in a waste of frequency domain resources.

[0119] In the embodiments of the present application, the maximum transmission bandwidth of the terminal is determined according to the type of the terminal, so that the maximum transmission bandwidth of the terminal matches the type of the terminal, and further the minimum protection bandwidth of the terminal matches the type of the terminal, thereby solving the various disadvantages brought about by setting the maximum transmission bandwidth and the minimum protection bandwidth of the terminal to fixed values.

[0120] To facilitate understanding, the types of terminals involved in the embodiments of the present application are described, and this description constitutes part of the embodiments of the present application.

[0121] 1. A terminal that has the ability to reflect downlink carrier signals but does not have the ability to generate uplink carrier signals.

[0122] This type of terminal can be called a backscatter terminal. A backscatter terminal refers to a terminal that transmits uplink signals based on backscattering. This type of terminal does not have the ability to actively generate or produce uplink carrier signals, or is called not capable of actively performing uplink transmission. It is necessary to use the downlink carrier signal (i.e., the downlink carrier signal) for reflection to achieve uplink signal transmission. For example, a backscatter terminal can receive a downlink carrier signal. For example, the downlink carrier signal can be a single-frequency carrier signal, an orthogonal frequency division multiplexing (OFDM) signal that occupies a single subcarrier in the frequency domain, or an OFDM signal that occupies multiple subcarriers in the frequency domain. The backscatter terminal can modulate the uplink information to be transmitted on the received downlink carrier signal and reflect it in the uplink.

[0123] Backscatter terminals can include passive terminals and semi-passive terminals. Passive terminals are those that rely entirely on external energy for their power supply. For example, a passive terminal can receive energy signals sent by access network equipment and, through a rectifier or other means, convert the energy signals into DC voltage for power supply. This energy supports the passive terminal's demodulation of downlink signals and the reflected transmission of uplink modulated signals. Semi-passive terminals are those that rely on both external and internal energy supplies.

[0124] Optionally, for a backscatter terminal, the device providing the downlink carrier signal may be an access network device, a reader, a helper, or other device capable of stimulating a backscatter RF terminal. It is understood that the device providing the downlink carrier signal and the device providing the energy signal may be the same device or different devices, without limitation.

[0125] The backscatter terminal does not have the ability to generate an uplink carrier signal or a local high-frequency local oscillator. It only has a low-frequency clock. Due to the limitation of low power consumption, the clock sampling deviation of the low-frequency clock of the backscatter terminal is large, resulting in a large frequency error between sending uplink signals and receiving downlink signals.

[0126] In one design, passive terminals and semi-passive terminals can be terminals in the ambient IoT (A-IoT), and passive terminals, semi-passive terminals, etc. can be respectively referred to as passive A-IoT terminals and semi-passive A-IoT terminals.

[0127] 2. A terminal capable of generating an uplink carrier signal.

[0128] Terminals capable of generating uplink carrier signals include two categories: legacy terminals and active terminals in A-IoT, which can be referred to as active A-IoT terminals. The maximum value of the frequency error of the legacy terminal can be equal to X, and the maximum value of the frequency error of the active A-IoT terminal can be greater than X. In one implementation, X is a non-negative number, for example, X is equal to 0.1 parts per million (ppm). For example, the legacy terminal can be a terminal in 5G, which can be called a new radio (NR) terminal, or it can be a terminal in 4G, which can be called a long term evolution (LTE) terminal, or it can be a terminal in a narrowband IoT, which can be called a narrowband IoT (NB-IoT) terminal.

[0129] Active A-IoT terminals have the ability to actively generate uplink carrier signals and can actively perform uplink transmissions. However, unlike traditional terminals, they still require external energy, or a portion of the required energy, for signal transmission. Active A-IoT terminals do not require other devices to provide downlink carrier signals. They modulate the uplink signal on their own generated uplink carrier to enable uplink transmission. However, due to the low power consumption of active A-IoT terminals, the oscillator used to generate the local oscillation frequency is generally a ring oscillator. The residual frequency error is greater than that of traditional terminals, and the maximum frequency error is greater than X. For active A-IoT terminals, the typical maximum frequency error can be 1ppm, 5ppm, 10ppm, 20ppm, or 50ppm.

[0130] Example 1

[0131] In the first embodiment, the terminal or access network device can determine the maximum transmission bandwidth of the terminal according to the type of the terminal. As shown in FIG2 , a process is provided, including:

[0132] Step 210: The terminal determines the maximum transmission bandwidth of the terminal under the first channel bandwidth and the first subcarrier spacing.

[0133] In one implementation, the first channel bandwidth and the first subcarrier spacing may be the channel bandwidth and subcarrier spacing under the current transmission of the terminal, or may be described as: the terminal transmits signals with the access network device under the first channel bandwidth and the first subcarrier spacing, and the signal transmission includes uplink signal transmission and downlink signal transmission.

[0134] In one design, the first channel bandwidth and the first subcarrier spacing can be specified in the protocol, predefined, or configured to the terminal by the access network device, etc., without limitation. For example, the frequency bands specified in the protocol include: n8 band, n10 band, n28 band or other NR bands. Taking the n8 band as an example, the band is a frequency division duplexing (FDD) band, and the uplink frequency range of the band is 880MHz-915MHz, and the downlink frequency range is 925MHz-960MHz. Corresponding to the n8 band, if the subcarrier spacing configured in this band is 15kHz, the first channel bandwidth can be 5MHz, 10MHz, 15MHz or 20MHz. If the subcarrier spacing configured in this band is 30kHz, the first channel bandwidth can be 10MHz, 15MHz or 20MHz.

[0135] In one design, the first channel bandwidth includes a maximum transmission bandwidth and a minimum protection bandwidth. Among them, all frequency domain resources in the maximum transmission bandwidth can be used to transmit signals, and all frequency domain resources in the minimum protection bandwidth cannot be used to transmit signals. Using the example of the n8 band, if the first channel bandwidth is 5MHz and the configured subcarrier spacing is 15kHz, the maximum transmission bandwidth specified in the protocol is 25 resource blocks (RBs), and each RB occupies 12 subcarriers. Then, at a subcarrier spacing of 15kHz, each RB corresponds to 180kHz (12*15kHz=180kHz), and 25 RBs occupy 4.5MHz (25*180kHz=4500kHz=4.5MHz). The minimum protection bandwidth specified in the protocol satisfies the following: minimum protection bandwidth = (channel bandwidth-maximum transmission bandwidth) / 2-subcarrier spacing / 2. In the above example, the channel bandwidth is 5 MHz, the maximum transmission bandwidth is 4.5 MHz, and the subcarrier spacing is 15 kHz. Therefore, the minimum guard bandwidth can be (5 MHz - 4.5 MHz) / 2 - 15 kHz / 2 = 242.5 kHz. The minimum guard bands are located on both sides of the maximum transmission bandwidth, each occupying 242.5 kHz.

[0136] In one design, under the first channel bandwidth and the first subcarrier spacing, the maximum transmission bandwidth of a terminal is associated with its type. Alternatively, step 210 may be described as follows: under the first channel bandwidth and the first subcarrier spacing, the terminal determines its maximum transmission bandwidth based on its type. Optionally, the terminal type may also be referred to as the terminal capability. Different terminal types have different corresponding frequency offset calibration capabilities.

[0137] For example, the types of terminals include: a terminal capable of generating an uplink carrier signal, and a terminal capable of reflecting a downlink carrier signal but not generating an uplink carrier signal.

[0138] 1. Terminals that reflect downlink carrier signals but lack the ability to generate uplink carrier signals are also called backscatter terminals. Backscatter terminals include passive terminals and semi-passive terminals. Backscatter terminals do not automatically generate uplink carrier signals and rely on downlink carrier signals sent by other devices for uplink transmission.

[0139] 2. Terminals capable of generating uplink carrier signals may include: terminals whose maximum frequency error is equal to X and terminals whose maximum frequency error is greater than X.

[0140] Terminals with a maximum frequency error equal to X can be traditional terminals, such as NR terminals, LTE terminals, or NB-IoT terminals. Terminals with a maximum frequency error greater than X can be active terminals in A-IoT, referred to as active A-IoT terminals.

[0141] In one design, for the first channel bandwidth, there is a correspondence between the terminal type and the maximum transmission bandwidth. The correspondence between the terminal type and the maximum transmission bandwidth can be specified by the protocol, predefined, or configured by the access network device for the terminal, etc., and is not limited. Under the current first channel bandwidth, the terminal can determine the maximum transmission bandwidth of the terminal based on its own type in the correspondence between the terminal type and the maximum transmission bandwidth. Thereafter, the terminal determines the minimum protection bandwidth based on the first channel bandwidth and the maximum transmission bandwidth. For example, the minimum protection bandwidth satisfies the following: minimum protection bandwidth = (first channel bandwidth - maximum transmission bandwidth) / 2 - subcarrier spacing / 2.

[0142] For backscatter terminals, there is frequency offset. Setting the minimum guard bandwidth is mainly used to address the frequency offset of backscatter terminals. For example, the first channel bandwidth of a passive terminal is 1 RB. When the subcarrier spacing is 15 kHz, 1 RB occupies 180 kHz (15 kHz * 12 = 180 kHz). If the maximum frequency error of the passive terminal is equal to 7%, then within the first channel bandwidth, the frequency offset of the passive terminal is equal to 180 kHz * 7% = 12.6 kHz. Therefore, the minimum guard bandwidth configured for the passive terminal needs to be greater than or equal to 12.6 kHz.

[0143] For traditional and active A-IoT terminals, carrier frequency errors exist. Setting a minimum guard bandwidth is primarily used to address this: The frequency error between traditional and active A-IoT terminals can be measured in ppm. For example, the maximum frequency error of an active A-IoT terminal is 10 ppm. At a 900 MHz carrier frequency, 10 ppm corresponds to a maximum actual frequency deviation of 9 kHz (900 MHz * 10 ppm). Therefore, the minimum guard bandwidth configured for active A-IoT terminals must be greater than or equal to 9 kHz.

[0144] In one design, traditional terminals and active A-IoT terminals have a stronger frequency offset calibration capability than backscatter terminals. Therefore, the minimum guard bandwidth corresponding to traditional terminals and active A-IoT terminals can be smaller than that of backscatter terminals. Given a fixed first channel bandwidth for a terminal, the relationship between the minimum guard bandwidth and the maximum transmission bandwidth is as follows: the smaller the minimum guard bandwidth, the larger the maximum transmission bandwidth. Conversely, the larger the minimum guard bandwidth, the smaller the maximum transmission bandwidth.

[0145] In other words, the maximum transmission bandwidth of traditional terminals and active A-IoT terminals can be greater than that of backscatter terminals. Alternatively, the maximum transmission bandwidth of a terminal capable of generating uplink carrier signals can be greater than the maximum transmission bandwidth of a terminal capable of backscattering downlink carrier signals but not generating uplink carrier signals.

[0146] In one design, for traditional terminals and active A-IoT terminals, the traditional terminal's frequency offset calibration capability is stronger than that of the active A-IoT terminal. For example, the maximum frequency error for the traditional terminal is equal to X, while the maximum frequency error for the active A-IoT terminal is equal to or greater than X. The minimum protection bandwidth corresponding to the traditional terminal is smaller than the minimum protection bandwidth corresponding to the active A-IoT terminal. Furthermore, the maximum transmission bandwidth corresponding to the traditional terminal is larger than the maximum transmission bandwidth corresponding to the active A-IoT terminal. Alternatively, it can be described as follows: the maximum transmission bandwidth corresponding to the terminal whose maximum frequency error is equal to X is larger than the maximum transmission bandwidth corresponding to the terminal whose maximum frequency error is equal to or greater than X.

[0147] For example, the first channel bandwidth of the active A-IoT terminal and the traditional terminal is 180kHz, the first subcarrier spacing is 15kHz, and both operate in the 1.8GHz frequency band. The maximum frequency error of the active A-IoT terminal is 10ppm. In the 1.8GHz frequency band, the actual frequency corresponding to 10ppm is equal to 18kHz (1.8GHz*10ppm), that is, the maximum frequency deviation of the active A-IoT terminal is equal to 18kHz. In one design, within the 180kHz channel bandwidth of the active terminal, the maximum transmission bandwidth can be configured to 135kHz, and the minimum protection bandwidth configured on both sides of the maximum transmission bandwidth can be 22.5kHz. For the traditional terminal, the maximum frequency error is 1ppm. In the 1.8GHz frequency band, the actual frequency corresponding to 1ppm is equal to 0.18kHz. In one design, within the 180kHz channel bandwidth of the traditional terminal, the maximum transmission bandwidth can be configured to 170kHz, and the minimum protection bandwidth configured on both sides of the maximum transmission bandwidth can be 5kHz. It can be seen that under the same conditions, the maximum transmission bandwidth corresponding to the traditional terminal is 170kHz, which is larger than the maximum transmission bandwidth corresponding to the active A-IoT terminal of 135kHz.

[0148] Step 220: The terminal transmits signals with the access network device according to the maximum transmission bandwidth of the terminal.

[0149] In one design, after the terminal determines the maximum transmission bandwidth of the terminal, it can transmit signals with the access network device within the maximum transmission bandwidth. The signal transmission can be an uplink signal transmission or a downlink signal bandwidth. For example, the maximum transmission bandwidth of the terminal includes 10 RBs, and the indexes of the 10 RBs are 0 to 9. When the subcarrier spacing is 15 kHz, each RB occupies 180 kHz. The access network device can configure the signal bandwidth for the terminal within the maximum transmission bandwidth of the terminal. The signal bandwidth can be an uplink signal bandwidth or a downlink signal bandwidth. For example, the access network device can instruct or configure the terminal to transmit signals on the RBs with indexes 0 and 1. The terminal can then determine the RBs corresponding to indexes 0 and 1 within the maximum transmission bandwidth of the terminal, and send uplink signals or receive downlink signals on the RBs corresponding to indexes 0 and 1. The RBs corresponding to indexes 0 and 1 can be considered as the uplink signal bandwidth or downlink signal bandwidth of the terminal.

[0150] In one design, the terminal's maximum uplink transmission bandwidth and maximum downlink transmission bandwidth can be the same. The "maximum transmission bandwidth" of a terminal mentioned above may refer to either the maximum uplink transmission bandwidth or the maximum downlink transmission bandwidth. Alternatively, the terminal's maximum uplink transmission bandwidth and maximum downlink transmission bandwidth can be different. The "maximum transmission bandwidth" of a terminal mentioned above includes both the maximum uplink transmission bandwidth and the maximum downlink transmission bandwidth. Furthermore, the terminal's maximum uplink transmission bandwidth can be greater than its maximum downlink transmission bandwidth. For example, when the first channel bandwidth is 360 kHz, the terminal's maximum uplink transmission bandwidth can be 320 kHz, and the terminal's maximum downlink transmission bandwidth can be 180 kHz. This design is primarily based on the following considerations: When a terminal accesses the network, it first receives a downlink signal. This downlink signal can be a synchronization signal or other broadcast signal. The terminal can perform frequency correction based on this downlink signal. This reduces the terminal's frequency error, thereby supporting a larger maximum transmission bandwidth during uplink transmission. For example, if no frequency correction is performed, the frequency error of an active A-IoT terminal is 100ppm. In the 900MHz frequency band, this corresponds to an actual frequency error of 9kHz. If the first channel bandwidth of an active A-IoT terminal is 360kHz, the maximum downlink transmission bandwidth of the active A-IoT terminal can be configured to 180kHz, and the minimum protection bandwidth can be configured to 90kHz ((360kHz - 180kHz) / 2). Upon receiving the downlink signal, the active A-IoT terminal performs frequency correction based on the downlink signal. After correction, the residual frequency error of the active A-IoT terminal is 10ppm, which corresponds to an actual frequency error of 0.9kHz in the 900MHz frequency band. At this point, the maximum uplink transmission bandwidth of the active A-IoT terminal can be configured to 320kHz, and the minimum protection bandwidth can be configured to 20kHz ((360-320) / 2). It can be seen that for an active A-IoT terminal, the maximum uplink transmission bandwidth of 320kHz is greater than the maximum downlink transmission bandwidth of 180kHz.

[0151] Optionally, the process in FIG2 may further include:

[0152] Step 230: The access network device determines the maximum transmission bandwidth of the terminal under the first channel bandwidth and the first subcarrier spacing.

[0153] The process by which the access network device determines the maximum transmission bandwidth of a terminal is similar to the process by which the terminal determines the maximum transmission bandwidth of the terminal. For example, the access network device may determine the maximum transmission bandwidth of the terminal based on the terminal type, under the first channel bandwidth and the first subcarrier spacing. There are no restrictions on how the access network device obtains the terminal type. For example, the terminal may proactively report its type to the access network device. For example, in one implementation, when accessing the access network device, the terminal may proactively report its type to the access network device. For other details regarding the access network device's determination of the terminal's maximum transmission bandwidth, please refer to the terminal's description and will not be repeated here.

[0154] It is understood that step 220 describes the following: after the terminal determines its maximum transmission bandwidth, it can transmit to the access network device based on the terminal's maximum transmission bandwidth. Optionally, in step 230, after the access network device determines the terminal's maximum transmission bandwidth, it can transmit signals to the terminal based on the terminal's maximum transmission bandwidth. Signal transmission can include uplink signal transmission and / or downlink signal transmission. Unlike the terminal side, the access network device can schedule uplink or downlink signal transmission for the terminal based on the terminal's maximum transmission bandwidth.

[0155] For example, if the maximum transmission bandwidth of a terminal includes 10 RBs, the access network device determines one or more RBs within the 10 RBs corresponding to the terminal's maximum transmission bandwidth as the downlink signal bandwidth or the uplink signal bandwidth, and configures or indicates the RBs corresponding to the downlink signal bandwidth or the uplink signal bandwidth to the terminal. For downlink transmission, the access network device sends a downlink signal to the terminal within the downlink signal bandwidth. Accordingly, the terminal receives the downlink signal sent by the access network device within the downlink signal bandwidth. For uplink transmission, the terminal sends an uplink signal to the access network device within the uplink signal bandwidth. Accordingly, the access network device receives the uplink signal sent by the terminal within the uplink signal bandwidth.

[0156] In the scheme of Figure 2, the following description focuses on: the terminal and the access network device each determine the maximum transmission bandwidth of the terminal based on the terminal type. The process of communicating with the other end is then based on the maximum transmission bandwidth of the terminal. Alternatively, in one design, the access network device can determine the maximum transmission bandwidth of the terminal based on the terminal type. The access network device can configure or indicate the maximum transmission bandwidth of the terminal to the terminal. The terminal can obtain the maximum transmission bandwidth of the terminal based on the configuration or instruction of the access network device. In this design, since the terminal does not need to determine the maximum transmission bandwidth of the terminal based on the terminal type, the terminal's energy consumption can be saved. Alternatively, in another design, the terminal can determine the maximum transmission bandwidth of the terminal based on its own type and report the maximum transmission bandwidth of the terminal to the access network device. The access network device can obtain the maximum transmission bandwidth of the terminal based on the terminal's report, without having to determine the maximum transmission bandwidth of the terminal itself.

[0157] In one implementation, in current wireless communication systems, such as 5G communication systems, as the first channel bandwidth of a terminal increases, the proportion of the minimum guard bandwidth to the first channel bandwidth decreases, while the proportion of the maximum transmission bandwidth to the first channel bandwidth increases. For example, in frequency bands below 6 GHz, the minimum first channel bandwidth of a terminal is 5 MHz and the maximum is 100 MHz. Within the range of 5 MHz to 100 MHz, if the subcarrier spacing is 15 kHz, as the first channel bandwidth gradually increases, the proportion of the minimum guard bandwidth to the first channel bandwidth gradually decreases, while the proportion of the maximum transmission bandwidth to the first channel bandwidth gradually increases. For example, when the first channel bandwidth is 5 MHz, the maximum transmission bandwidth is 25 RBs, or 4.32 MHz, accounting for 90% of the maximum transmission bandwidth. When the first channel bandwidth is 10 MHz, the maximum transmission bandwidth is 52 RBs, or 9.36 MHz, accounting for 93.6% of the maximum transmission bandwidth. When the first channel bandwidth is 15 MHz, the maximum transmission bandwidth is 79 RBs, or 14.22 MHz, accounting for 94.8% of the maximum transmission bandwidth. In an embodiment of the present application, the frequency error of the backscatter terminal may jitter as the channel bandwidth increases, and the proportional relationship between the maximum transmission bandwidth and the first channel bandwidth does not satisfy the definition that as the first channel bandwidth increases, the proportion of the minimum protection bandwidth gradually decreases and the proportion of the maximum transmission bandwidth gradually increases.

[0158] In one design, the maximum transmission bandwidth and minimum guard bandwidth of a terminal are associated with the frequency band in which the terminal resides. The higher the corresponding frequency value of the frequency band, the smaller the maximum transmission bandwidth of the terminal and the larger the minimum guard bandwidth. Optionally, the minimum guard bandwidth is proportional to the carrier frequency, carrier center frequency, band start frequency, or band cutoff frequency. For example, if the carrier frequency is 900 MHz and the frequency error is 0.1 ppm, the frequency deviation is 9 kHz; if the carrier frequency is 1.8 GHz and the frequency error is 0.1 ppm, the frequency deviation is 18 kHz.

[0159] In the first embodiment, different types of terminals have different frequency offset calibration capabilities. In this embodiment of the present application, a maximum transmission bandwidth that matches the terminal's frequency offset calibration capability can be determined based on the terminal type. For example, for a terminal with poor frequency offset calibration capabilities, a larger minimum protection bandwidth and a smaller maximum transmission bandwidth can be configured. For a terminal with good frequency offset calibration capabilities, a smaller minimum protection bandwidth and a larger maximum transmission bandwidth can be configured, thereby ensuring that the maximum transmission bandwidth configured for the terminal matches its frequency offset calibration capability.

[0160] Example 2

[0161] The solution of embodiment 2: is mainly used to compare the maximum signal bandwidths of two uplink signals. For example, the uplink signal sent first by the terminal is called the first uplink signal, and the uplink signal sent later is called the second uplink signal. The maximum signal bandwidth of the second uplink signal may be greater than the maximum signal bandwidth of the first uplink signal. The main considerations are as follows: the terminal can perform frequency correction based on the first uplink signal sent first. Therefore, after correction, the frequency error of the terminal will become smaller, and therefore, the maximum signal bandwidth supported by the second uplink signal may be smaller than the maximum signal bandwidth supported by the first uplink signal. Compared with the maximum signal bandwidth configured with the same configuration as the first uplink signal, the transmission efficiency and frequency domain resource utilization of the uplink transmission of different uplink transmission stages, different uplink channels, and different uplink signals can be improved. As shown in Figure 3, a process is provided, which at least includes:

[0162] Step 310: The terminal sends a first uplink signal to the access network device on the first uplink channel. The access network device receives the first uplink signal from the terminal on the first uplink channel.

[0163] Step 320: The terminal sends a second uplink signal to the access network device on the second uplink channel. The access network device receives the second uplink signal from the terminal on the second uplink channel.

[0164] In one design, the maximum signal bandwidth of the second uplink signal is greater than the maximum signal bandwidth of the first uplink signal. Optionally, the maximum value of the frequency error of the first uplink signal may be a first value, and the maximum value of the frequency error of the second uplink signal may be a second value, and the second value may be smaller than the first value. In other words, because the maximum value of the frequency error of the second uplink signal is smaller than the maximum value of the frequency error of the first uplink signal, the second uplink signal can support a larger maximum signal bandwidth than the first uplink signal.

[0165] In one implementation, a first uplink signal corresponds to a first bandwidth set, and a second uplink signal corresponds to a second bandwidth set. The first bandwidth set and the second bandwidth set can be specified by a protocol, preset, or configured for a terminal by an access network device, without limitation. Optionally, the first uplink signal corresponding to the first bandwidth set can also be referred to as the first uplink channel corresponding to the first bandwidth set, and the second uplink signal corresponding to the second bandwidth set can also be referred to as the second uplink channel corresponding to the second bandwidth set. The first bandwidth set and the second bandwidth set each include at least one signal bandwidth. During actual transmission, the access network device can configure a signal bandwidth from the first bandwidth set to the terminal, and the terminal transmits the first uplink signal on the first uplink channel according to the configured signal bandwidth. The access network device can configure a signal bandwidth from the second bandwidth set to the terminal, and the terminal transmits the second uplink signal on the second uplink channel according to the configured signal bandwidth. In this embodiment of the present application, the relationship between the signal bandwidth of the first uplink signal transmitted on the first uplink channel and the signal bandwidth of the second uplink signal transmitted on the second uplink channel is not restricted; only the relationship between the maximum signal bandwidth in the second bandwidth set and the maximum signal bandwidth in the first bandwidth set is defined. For example, the maximum signal bandwidth in the second bandwidth set is greater than the maximum signal bandwidth in the first bandwidth set. It is understood that the maximum signal bandwidth in the second bandwidth set is the aforementioned maximum signal bandwidth of the second uplink signal, and the maximum signal bandwidth in the first bandwidth set is the aforementioned maximum signal bandwidth of the first uplink signal. For example, if the terminal's maximum transmission bandwidth is 180 kHz, then the first bandwidth set corresponding to the first uplink signal includes 15 kHz, 30 kHz, 60 kHz, and 120 kHz. The second bandwidth set corresponding to the second uplink signal includes 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 150 kHz. It can be seen that the maximum signal bandwidth in the second bandwidth set, i.e., the maximum signal bandwidth of the second uplink signal of 150 kHz, is greater than the maximum signal bandwidth in the first bandwidth set, i.e., the maximum signal bandwidth of the first uplink signal of 120 kHz. In actual transmission, the access network device can configure or indicate any of the four signal bandwidths included in the first bandwidth set to the terminal, and the terminal will transmit the first uplink signal on the first uplink channel using the configured or indicated signal bandwidth. Similarly, the access network device can configure or indicate any one of the five signal bandwidths included in the second bandwidth set to the terminal, and the terminal transmits the second uplink signal on the second uplink channel using the configured or indicated signal bandwidth.

[0166] It is understood that the maximum transmission bandwidth of the first uplink signal and the maximum transmission bandwidth of the second uplink signal should be less than or equal to the maximum transmission bandwidth of the terminal. For example, the first channel bandwidth of the terminal is 180kHz, and the maximum transmission bandwidth of the terminal is 160kHz. The first bandwidth set of the first uplink signal or the second bandwidth set of the second uplink signal configured by the access network device for the terminal may include: 15kHz, 30kHz, 60kHz, 120kHz, and 150kHz. It can be seen that the maximum signal bandwidth in this bandwidth set is 150kHz, which is less than the maximum transmission bandwidth of 160kHz for the terminal.

[0167] Optionally, between step 310 and step 320, the following may be further included: step 330: the access network device sends a first downlink signal to the terminal on the first downlink channel. The terminal receives the first downlink signal from the access network device on the first downlink channel.

[0168] In one design, the first downlink signal includes frequency adjustment information. For example, the frequency adjustment information of the first uplink signal includes one or more of the following: a frequency error of the first uplink signal, a maximum value of the frequency error of the first uplink signal, a frequency adjustment command of the second uplink signal, or a frequency adjustment value of the second uplink signal. Taking the example of an access network device determining the frequency error of the first uplink signal, upon receiving the first uplink signal, the access network device may determine the frequency of the first uplink signal through detection. The access network device compares the detected frequency of the first uplink signal with the indicated or configured frequency of the first uplink signal, obtains a frequency difference between the two, and thereby determines the frequency error of the first uplink signal. The frequency of the first uplink signal may refer to a frequency range of the first uplink signal, a center frequency of the first uplink signal, or a starting or ending frequency of the first uplink signal. That is, in this embodiment of the present application, the access network device determines the frequency error of the first uplink signal by comparing two frequency ranges of the first uplink signal. Alternatively, the access network device may determine the frequency error of the first uplink signal by comparing two center frequencies of the first uplink signal. Alternatively, the access network device may determine the frequency error of the first uplink signal by comparing the starting frequency or the ending frequency of the first uplink signal. Taking the example of the access network device determining the frequency error of the first uplink signal by comparing two frequency ranges of the first uplink signal, for example, the access network device indicates or configures a signal bandwidth of 15 kHz for the first uplink signal, and a frequency range of 920 MHz to 920.015 MHz. When receiving the first uplink signal, the access network device detects that the frequency range of the first uplink signal is 920.015 MHz to 920.030 MHz. The access network device may determine that the frequency error of the first uplink signal is +15 kHz. It will be understood that if the value of the determined frequency error of the first uplink signal is positive, it indicates that the frequency of the received first uplink signal deviates in an increasing direction relative to the indicated or configured frequency of the first uplink signal. Conversely, if the value of the determined frequency error of the first uplink signal is negative, it indicates that the frequency of the received first uplink signal deviates in a decreasing direction relative to the indicated or configured frequency of the first uplink signal.

[0169] In one design, a terminal may obtain frequency adjustment information from a first downlink signal. The terminal performs frequency adjustment based on the frequency adjustment information. After the frequency adjustment, the terminal transmits a second uplink signal to the access network device on a second uplink channel. For example, the terminal may adjust its own frequency oscillator based on the frequency error of the first uplink signal. After the adjustment, the terminal's frequency error is reduced compared to before the adjustment. Therefore, the second downlink signal can support a larger maximum signal bandwidth than the first downlink signal. For example, within the terminal's channel, the maximum configurable signal bandwidth of the first uplink signal is 150 kHz. In a frequency band with a carrier center frequency of 900 MHz, the frequency error of the first uplink signal is approximately 20 ppm, resulting in a frequency error of 18 kHz. The terminal may obtain the 20 ppm frequency error of the first uplink signal from the first downlink signal. After the frequency adjustment, the terminal's frequency error is approximately 5 ppm, resulting in a frequency error of 4.5 kHz for the second uplink signal. The maximum configurable signal bandwidth of the second uplink signal may be 170 kHz, which is greater than the 150 kHz maximum configurable signal bandwidth of the first uplink signal.

[0170] Example 1

[0171] In the random access scenario, the method in the process of Figure 3 can be applied. Taking the four-step random access as an example, the four-step random access process of the terminal includes:

[0172] Step 1: The terminal sends a message 1 on a physical random access channel (PRACH). Message 1 is a random access preamble. Optionally, the random access preamble may also be called a random access preamble sequence.

[0173] In one design, the first uplink signal in the process of Figure 3 may be a signal carrying message 1.

[0174] Step 2: The access network device sends a message 2 on a physical downlink shared channel (PDSCH). Message 2 may be called a random access response (RAR).

[0175] In one design, the first downlink signal in the process of FIG3 may be a signal carrying Message 2. Message 2 may carry frequency adjustment information. The terminal may perform frequency adjustment based on the frequency adjustment information.

[0176] Step 3: The terminal sends message 3 to the access network device on the physical uplink shared channel (PUSCH).

[0177] In one design, if Message 2 carries frequency adjustment information, the uplink signal carrying Message 3 may be referred to as a second uplink signal. The maximum signal bandwidth of the uplink signal carrying Message 3 is greater than the maximum signal bandwidth of the uplink signal carrying Message 1.

[0178] Step 4: The access network device sends a message 4 to the terminal on the PDSCH. The message 4 may be called a contention resolution message.

[0179] In one design, the first downlink signal in the process of FIG3 may be a signal carrying message 4. Message 4 may carry frequency adjustment information. The terminal may perform frequency adjustment based on the frequency adjustment information.

[0180] Through the aforementioned steps 1 to 4, when the terminal successfully accesses the random access, the access network device can schedule the terminal to send the first uplink signal to the access network device on the PUSCH, and the first uplink signal can carry message 5. That is, the message carried in the first uplink signal sent after the terminal successfully accesses the random access can be called message 5, or the first uplink message sent after the terminal successfully accesses the random access can be called message 5, etc. If message 4 carries frequency adjustment information, the uplink signal carrying message 5 can be called the second uplink signal in the process of Figure 3, and the maximum signal bandwidth corresponding to the second uplink signal can be greater than the maximum signal bandwidth of the first uplink signal. At this time, the first uplink signal can be the uplink signal carrying message 1, or the uplink signal carrying message 3. That is to say, the maximum signal bandwidth of the uplink signal carrying message 5 is greater than the maximum signal bandwidth of the uplink signal carrying message 1 or message 3.

[0181] Summarizing the above four-step random access process, we can get the following: In one design, the uplink signal carrying message 1 can be called the first uplink signal. Optionally, the downlink signal carrying message 2 can be called the first downlink signal, and the first downlink signal carries frequency adjustment information. The terminal can perform frequency adjustment according to the frequency adjustment information. Afterwards, the uplink signal carrying message 3 can be called the second uplink signal. Alternatively, the uplink signal after carrying message 3 (for example, message 5) can be called the second uplink signal. At this time, the maximum signal bandwidth of the second uplink signal carrying message 3 or message 5 is greater than the maximum signal bandwidth of the first uplink signal carrying message 1. The first uplink channel is PRACH, and the second uplink channel is PUSCH or PUCCH. Alternatively,

[0182] In one design, the uplink signal carrying message 3 may be referred to as the first uplink signal. The downlink signal carrying message 4 may be referred to as the first downlink signal, and the first downlink signal includes frequency adjustment information. The terminal may perform frequency adjustment based on the frequency adjustment information. The uplink signal after message 3 may be referred to as the second uplink signal. For example, the second uplink signal may be an uplink signal carrying an acknowledgement (ACK) or a negative acknowledgement (NACK) of message 4 or an uplink signal carrying message 5. At this time, the maximum signal bandwidth of the second uplink signal carrying the ACK or NACK of message 4 or message 5 is greater than the maximum signal bandwidth of the first uplink signal carrying message 3. The first uplink channel is PUSCH. And when the second uplink signal is the uplink signal carrying message 4, the second uplink channel is PUCCH. Alternatively, when the second uplink signal is the uplink signal carrying message 5, the second uplink channel is PUSCH.

[0183] Of course, in one implementation, a first bandwidth set may be configured for the first uplink signal, and a second bandwidth set may be configured for the second uplink signal. The access network device may configure or instruct the terminal to transmit the first uplink signal within a signal bandwidth included in the first bandwidth set. The access network device may configure or instruct the terminal to transmit the second uplink signal within a signal bandwidth included in the second bandwidth set. The maximum signal bandwidth included in the second bandwidth set is greater than the maximum signal bandwidth included in the first bandwidth set.

[0184] Example 2

[0185] In the random access scenario, the method in the process of Figure 3 can be applied. Taking two-step random access as an example, the two-step random access of the terminal includes:

[0186] Step 1: The terminal sends Message A to the access network device. In one implementation, Message A includes Messages 1 and 3 of the four-step random access process. In one implementation, the terminal sends a random access preamble to the access network device on the PRACH and sends data to the access network device on the PUSCH.

[0187] In one design, the first uplink signal in the process of FIG3 may be a signal carrying message A, and the first uplink channel may be a PRACH or a PUSCH.

[0188] Step 2: The access network device sends a message B to the terminal on the PDSCH. In one implementation, the message B includes message 2 and message 4 in the four-step random access process.

[0189] In one design, the first downlink signal in the process of FIG3 may be a signal carrying message B, which may include frequency adjustment information. The first downlink channel may be a PDSCH. The terminal may perform frequency adjustment based on the frequency adjustment information. After the terminal successfully completes random access, the first uplink signal sent by the terminal to the access network device carries message 5. The uplink signal carrying message 5 may be referred to as a second uplink signal, and the second uplink channel may be a PUSCH. The maximum signal bandwidth of the second uplink signal is greater than the maximum signal bandwidth of the first uplink signal. That is, the maximum signal bandwidth of the uplink signal carrying message 5 is greater than the maximum signal bandwidth of the uplink signal carrying message A.

[0190] Of course, in this embodiment of the present application, a first bandwidth set can be configured for the first uplink signal carrying message A, and a second bandwidth set can be configured for the second uplink signal carrying message 5. The maximum signal bandwidth in the second bandwidth set is greater than the maximum signal bandwidth in the first bandwidth set. The access network device can configure or instruct the terminal to transmit the first uplink signal using a signal bandwidth in the first bandwidth set. The access network device can also configure or instruct the terminal to transmit the second uplink signal using a signal bandwidth in the second bandwidth set.

[0191] Example 3

[0192] In an asynchronous system, the method in the process of Figure 3 can be applied. In an asynchronous system, before a terminal sends a data signal to an access network device, it must first send a synchronization signal or reference signal to the access network device. The synchronization signal or reference signal is used for time synchronization between the access network device and the terminal. That is, the terminal may first send the synchronization signal or reference signal to the access network device, and then send the data signal to the access network device. In one design, the first uplink signal in the process of Figure 3 may be a synchronization signal or reference signal, and the second uplink signal may be a signal carrying uplink data information or a signal carrying uplink control information. The synchronization signal or reference signal is a synchronization signal or reference signal for the second uplink signal, or may be associated with the second uplink signal, and is used for time synchronization between the access network device and the terminal. The maximum signal bandwidth of the data signal is greater than the maximum signal bandwidth of the synchronization signal or reference signal. In one implementation, the synchronization signal or reference signal is transmitted in the PUSCH, and the second uplink signal may be transmitted in the PUSCH or PUCCh. That is, the first uplink channel in the process of Figure 3 can be PUSCH, and the second uplink channel can be PUCCH or PUSCH. Through the above design, by detecting and adjusting the frequency of the reference signal or synchronization signal with a shorter transmission duration, the transmission efficiency and frequency domain resource utilization can be further improved when the uplink data signal with a longer transmission duration is subsequently transmitted.

[0193] In one design, between the terminal sending a synchronization signal or reference signal and the terminal sending a second uplink signal, the terminal further includes: receiving a first downlink signal from an access network device on a first downlink channel, the first downlink signal including frequency adjustment information. The first downlink signal may be a data signal or a control signal, and the first downlink channel may be, for example, a PDSCH or a physical downlink control channel (PDCCH), without limitation. For example, in one implementation, the terminal sends a synchronization signal or reference signal to the access network device on a PUSCH. The access network device performs time synchronization with the terminal based on the synchronization signal or reference signal. The access network device determines frequency adjustment information based on the synchronization signal or reference signal. The access network device sends the first downlink signal to the terminal on the first downlink channel, the first downlink signal including frequency adjustment information, and the first downlink channel may be, for example, a PDSCH or a PDCCH. The terminal adjusts the frequency of its frequency oscillator based on the frequency adjustment information. After the adjustment, the maximum frequency error of the terminal after the adjustment is less than the maximum frequency error of the terminal before the adjustment. The terminal then sends the second uplink signal to the access network device on a PUSCH. The maximum signal bandwidth of the second uplink signal is greater than the maximum signal bandwidth of the synchronization signal or the reference signal.

[0194] Of course, in the embodiment of the present application, a first bandwidth set may be configured for the synchronization signal or reference signal, and a second bandwidth set may be configured for the second uplink signal. The maximum signal bandwidth in the second bandwidth set is greater than the maximum signal bandwidth in the first bandwidth set.

[0195] In one design, the terminal or access network device may determine the maximum signal bandwidth of the first uplink signal and the maximum signal bandwidth of the second uplink signal based on the type of the terminal. The maximum signal bandwidth of the second uplink signal is greater than the maximum signal bandwidth of the first uplink signal. In one implementation, the terminal or access network device may determine the maximum transmission bandwidth of the terminal based on the type of the terminal. For the process of determining the maximum transmission bandwidth of the terminal based on the type of the terminal and the description of the terminal type, please refer to the description in Example 1. The terminal or access network device may determine the maximum signal bandwidth of the first uplink signal and the maximum signal bandwidth of the second uplink signal based on the maximum transmission bandwidth of the terminal. The maximum signal bandwidth of the first uplink signal and the maximum signal bandwidth of the second uplink signal are less than or equal to the maximum transmission bandwidth of the terminal.

[0196] Of course, in this embodiment of the present application, a first bandwidth set can be configured for the first uplink signal, and a second bandwidth set can be configured for the second uplink signal. The maximum signal bandwidth in the first bandwidth set is referred to as the maximum signal bandwidth of the first uplink signal, and the maximum signal bandwidth in the second bandwidth set is referred to as the maximum signal bandwidth of the second uplink signal. In one description, the first bandwidth set and the second bandwidth set can be configured based on the maximum transmission bandwidth of the terminal. Of course, any signal bandwidth included in the first bandwidth set and the second bandwidth set must be less than or equal to the maximum transmission bandwidth of the terminal.

[0197] In one implementation, the access network device and the terminal each perform the following process: determining the maximum transmission bandwidth of the terminal based on the type of the terminal. Determining a first bandwidth set and a second bandwidth set based on the maximum transmission bandwidth of the terminal, etc. It is understandable that at this time, the first bandwidth set and the second bandwidth set determined by the access network device and the terminal each need to protect the same. Alternatively, the access network device may perform the above process to determine the first bandwidth set and the second bandwidth set. The access network device configures or indicates the first bandwidth set and the second bandwidth set to the terminal. Alternatively, the terminal may perform the above process to determine the first bandwidth set and the second bandwidth set based on the type of the terminal. The terminal reports the first bandwidth set and the second bandwidth set to the access network device, etc. It is understandable that the above description of determining the first bandwidth set and the second bandwidth set based on the maximum transmission bandwidth of the terminal can be replaced by: determining the maximum signal bandwidth of the first uplink signal and the maximum signal bandwidth of the second uplink signal based on the maximum transmission bandwidth of the terminal.

[0198] In one design, a terminal may report its terminal type to the access network device. For example, the terminal may send a message to the access network device that includes the terminal type. The message type is not limited. For example, the message may be Message 1 or Message 3 in a four-step random access process, or Message A in a two-step random access process. The access network device may receive the message from the terminal and obtain the terminal type from the message. Alternatively, the terminal may implicitly report its terminal type to the access network device using other information associated with the terminal type. For example, the random access preamble may be associated with the terminal type. For example, when the terminal type is Type 1, during the random access process, the terminal reports the random access preamble associated with Type 1 to the access network device. The access network device may determine that the terminal type is Type 1 based on the received random access preamble. Alternatively, the random access resources may be associated with the terminal type. For example, when the terminal type is Type 2, the terminal may use the random access resources associated with Type 2 to send the random access preamble to the access network device. The access network device may determine that the type of the terminal is type 2 based on the random access resource of the received random access preamble code.

[0199] It is understood that in the description of this application, the maximum signal bandwidth may also be referred to as a configurable maximum signal bandwidth, a configurable maximum signal bandwidth, an indicative maximum signal bandwidth, or an indicative maximum signal bandwidth. Furthermore, it may also be referred to as the maximum signal bandwidth in a set of configurable maximum signal bandwidths or the maximum signal bandwidth in a set of indicative maximum signal bandwidths.

[0200] The above design allows different uplink signal configurations to have different maximum signal bandwidths. For example, a terminal may first transmit a first uplink signal and then a second uplink signal. The maximum signal bandwidth of the second uplink signal configuration is greater than the maximum signal bandwidth of the first uplink signal configuration. This design, compared to a design where the maximum signal bandwidth of the second uplink signal configuration is the same as the maximum signal bandwidth of the first uplink signal configuration, improves transmission efficiency and frequency domain resource utilization for uplink transmissions of different uplink signals, across different uplink channels, and at different uplink transmission stages.

[0201] Example 3

[0202] The solution of embodiment three: is mainly used to compare the maximum signal bandwidth of two downlink signals. For example, the terminal first receives a first downlink signal from the access network device, and then receives a second downlink signal from the access network device. The maximum signal bandwidth of the second downlink signal is greater than the maximum signal bandwidth of the first downlink signal. This is mainly due to the following considerations: when the terminal receives the first downlink signal, it can perform frequency correction according to the first downlink signal. After frequency correction, the frequency error of the signal received by the terminal will become smaller. Therefore, thereafter, the maximum signal bandwidth supported by the second downlink signal sent by the access network device to the terminal can be larger. Compared with the second downlink signal and the first downlink signal configured with the same maximum signal bandwidth, the transmission efficiency and frequency domain resource utilization of different downlink transmission stages, different downlink channels, and different downlink signals can be improved. In particular, when a low-power, low-spectral-efficiency modulation method is used in the downlink, increasing the effective signal bandwidth can more effectively improve the transmission efficiency. As shown in Figure 4, a process is provided, which at least includes:

[0203] Step 410: The access network device sends a first downlink signal to the terminal on a first downlink channel. The terminal receives the first downlink signal from the access network device on the first downlink channel.

[0204] Step 420: The access network device sends a second downlink signal to the terminal on the second downlink channel. The terminal receives the second downlink signal from the access network device on the second downlink channel.

[0205] In one design, the first downlink signal is configured with a first bandwidth set, and the second downlink signal is configured with a second bandwidth set. The first bandwidth set and the second bandwidth set include at least one signal bandwidth. The maximum signal bandwidth of the first uplink signal may be the maximum signal bandwidth in the first bandwidth set, and the maximum signal bandwidth of the second uplink signal may be the maximum signal bandwidth in the second bandwidth set. In one implementation, the access network device may be configured or instructed that the terminal receives the first downlink signal in a signal bandwidth in the first bandwidth set. The access network device may be configured or instructed that the terminal receives the second downlink signal in a signal bandwidth in the second bandwidth set. There is no restriction on the size relationship between the signal bandwidth for transmitting the first downlink signal and the signal bandwidth for transmitting the second downlink signal.

[0206] In one design, between step 410 and step 420, the following is further included: step 430: the terminal performs frequency correction based on the first downlink signal. For example, in one implementation: when receiving the first downlink signal, the terminal can determine the frequency of the first downlink signal through detection. The access network device compares the frequency of the detected first downlink signal with the frequency of the indicated or configured first downlink signal, obtains frequency difference information between the two, and then determines the frequency error of the first downlink signal. The terminal performs frequency adjustment based on the frequency error of the first downlink signal. After the frequency adjustment, the terminal sends a second downlink signal to the access network device. Since the frequency error of the terminal will become smaller after the frequency adjustment, the maximum signal bandwidth supported by the second uplink signal is greater than the maximum signal bandwidth supported by the first uplink signal. In one implementation, the maximum value of the frequency error of the first uplink signal before adjustment is called the first value, and the maximum value of the frequency error of the second uplink signal after adjustment is called the second value, and the second value is smaller than the first value.

[0207] Example 1

[0208] In one design, the first downlink signal is used for at least one of the following: time synchronization, frequency synchronization, or carrying a system message. For example, when the first downlink signal is used for time synchronization, the first downlink signal may be a synchronization signal (SS) or a time synchronization signal (TSS). When the first downlink signal is used for frequency synchronization, the first downlink signal may be a synchronization signal or a frequency synchronization signal (FSS). When the first downlink signal is used for time synchronization and frequency synchronization, the first downlink signal may be a synchronization signal, which is used for both time synchronization and frequency synchronization. Furthermore, the synchronization signal may be a primary synchronization signal (PSS) or a secondary synchronization signal (SSS), etc., without limitation. When the first downlink signal is used to carry a system message, the first downlink signal may be a master information block (MIB) or a system information block (SIB), etc. In one implementation, the first downlink channel may be a physical broadcast channel (PBCH). The second downlink signal includes: a signal carrying downlink data information, or a signal carrying downlink control information. The second downlink channel may be a PDSCH or a PDCCH.

[0209] For example, consider a case where the first downlink signal is a synchronization signal, and the first downlink channel is the PBCH. The second downlink signal is a downlink data signal or a downlink control signal, and the second downlink channel is the PDSCH or PDCCH. The synchronization signal corresponds to the first bandwidth set, and the downlink data signal or downlink control signal corresponds to the second bandwidth set. The access network device can select a signal bandwidth from the first bandwidth set and use the selected signal bandwidth to transmit the synchronization signal to the terminal on the PBCH. Simultaneously, the access network device can configure or indicate the signal bandwidth to the terminal. The terminal receives the synchronization signal on the PBCH using the configured or indicated signal bandwidth. After receiving the synchronization signal, the terminal can perform frequency correction based on the synchronization signal. This frequency correction reduces the maximum frequency error of the terminal. Therefore, the maximum signal bandwidth in the second bandwidth set is greater than the maximum signal bandwidth in the first bandwidth set. The access network device can then select a signal from the second bandwidth set and use the selected signal bandwidth to transmit the data signal or control signal to the terminal on the PDSCH or PDCCH. Simultaneously, the access network device can configure or indicate the signal bandwidth to the terminal. The terminal receives a data signal on the PDSCH or receives a control signal on the PDCCH using the configured or indicated signal bandwidth.

[0210] Under the above design, by calibrating the frequency error of the existing public signal that can be used for periodic transmission, the transmission efficiency and frequency domain resource utilization can be further improved when the downlink data signal and control signal are subsequently transmitted.

[0211] Example 2

[0212] In one design, the first downlink signal is a synchronization signal or a reference signal, and the first downlink channel may be a PDSCH. The second downlink signal may carry downlink data information or a signal carrying downlink control information, and the second downlink channel may be a PDSCH or a PDCCH. The synchronization signal or reference signal is a synchronization signal or a reference signal of the second downlink signal, or the synchronization signal or reference signal is associated with the second downlink signal, or the synchronization signal or reference signal is used for synchronization between the terminal and the access network device.

[0213] In an asynchronous system, to ensure time synchronization between the access network device and the terminal, the access network device must first send a synchronization signal or reference signal to the terminal before sending data signals to the terminal. For example, in one implementation, the access network device sends a synchronization signal or reference signal to the terminal. Upon receiving this synchronization signal or reference signal, the terminal can perform frequency correction based on the synchronization signal or reference signal. This frequency correction reduces the terminal's frequency error. Consequently, the maximum signal bandwidth supported by the data signal sent by the access network device to the terminal is greater than the maximum signal bandwidth supported by the synchronization signal or reference signal.

[0214] In the above design, by calibrating the frequency error of the existing common frequency that can be used to send along with the data signal, the transmission efficiency and frequency domain resource utilization can be further improved when the downlink data signal and control signal are subsequently sent.

[0215] In one design, the access network device or the terminal may each determine the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal based on the terminal type. Of course, the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal determined by the access network device need to be aligned with the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal determined by the terminal. Alternatively, the access network device may determine the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal based on the terminal type, and configure or indicate the determined maximum signal bandwidth of the first downlink signal and the second downlink signal to the terminal. Alternatively, the terminal may determine the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal based on the terminal type. The terminal reports the determined maximum signal bandwidth of the first downlink signal and the second downlink signal to the access network device, etc. In this embodiment of the present application, the description of determining the maximum signal bandwidth of the first downlink signal and the second downlink signal based on the terminal type may be replaced by determining a first bandwidth set for the first downlink signal and a second bandwidth set for the second downlink signal based on the terminal type.

[0216] In one implementation, the process of determining the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the second downlink signal based on the type of the terminal includes: determining the maximum transmission bandwidth of the terminal based on the type of the terminal. For a description of the type of the terminal and determining the maximum transmission bandwidth of the terminal based on the type of the terminal, see Example 1. Furthermore, the maximum transmission bandwidth of the first uplink signal and the maximum transmission bandwidth of the second uplink signal may be determined based on the maximum transmission bandwidth of the terminal. The maximum transmission bandwidth of the first uplink signal and the maximum transmission bandwidth of the second uplink signal are less than the maximum transmission bandwidth of the terminal.

[0217] In one design, the terminal may report its type to the access network device. For example, the terminal may send a message to the access network device that includes the terminal type. The specific implementation of the terminal reporting its type to the access network device is described in Example 2 and is not further described here.

[0218] In this third embodiment, the maximum signal bandwidths configured for different downlink signals are not the same. For example, the access network device first sends a first downlink signal to the terminal. Since the terminal can perform frequency adjustment according to the first downlink signal when receiving the first downlink signal, the frequency error of the terminal will become smaller. Therefore, thereafter, the second downlink signal sent by the access network device to the terminal can support a larger maximum signal bandwidth. Compared with configuring the same maximum signal bandwidth for downlink signals, the transmission efficiency and frequency domain resource utilization of different downlink transmission stages, different downlink channels, and different downlink signals can be improved. In particular, when a low-power, low-spectrum-efficiency modulation method is used in the downlink, increasing the effective signal bandwidth can more effectively improve the transmission efficiency.

[0219] Example 4

[0220] The scheme of embodiment 4 is mainly used to compare the maximum signal bandwidth of the uplink signal and the downlink signal. Since the terminal first receives the downlink signal when accessing the system, the terminal can perform frequency correction based on the downlink signal. After correction, the maximum value of the frequency error of the terminal becomes smaller. Therefore, the maximum signal bandwidth of the uplink signal can be greater than the maximum signal bandwidth of the downlink signal. Compared with the maximum signal bandwidth configured for the uplink signal and the downlink signal, the uplink signal transmission efficiency and the utilization rate of the frequency domain resources can be improved. As shown in Figure 5, a process is provided, including:

[0221] Step 510: The access network device sends a first downlink signal to the terminal on a first downlink channel. The terminal receives the first downlink signal from the access network device on the first downlink channel.

[0222] Step 520: The terminal sends a first uplink signal to the access network device on the first uplink channel. The access network device receives the first uplink signal from the terminal on the first uplink channel. The maximum signal bandwidth corresponding to the first uplink signal may be greater than the maximum signal bandwidth corresponding to the first downlink signal.

[0223] In one design, between step 510 and step 520, the following further includes: step 530: the terminal performs frequency correction based on the first downlink signal. After frequency correction, the maximum value of the terminal's frequency error decreases. For example, the maximum value of the frequency error of the first downlink signal is a first value, and the maximum value of the frequency error of the first uplink signal is a second value. Since the terminal performs frequency correction upon receiving the first downlink signal, the maximum value of the terminal's frequency error decreases after frequency correction. Therefore, the second value can be smaller than the first value.

[0224] In one design, the first downlink signal may be a synchronization signal, a signal carrying a system message, a downlink data signal, or a downlink control signal, and the first downlink channel may be a PBCH, a PDCCH, or a PDSCH, etc. The first uplink signal may be a random access preamble, an uplink data signal, or an uplink control signal, and the first uplink channel may be a PRACH, a PUSCH, or a physical uplink control channel (PUCCH), etc.

[0225] For example, consider a scenario where the first downlink signal is a synchronization signal, the first downlink channel is the PBCH, and the first uplink signal is an uplink data signal, also known as the PUSCH. The access network device transmits the synchronization signal to the terminal over the PBCH. Upon receiving the synchronization signal over the PBCH, the terminal performs frequency correction based on the synchronization signal. This frequency correction reduces the maximum frequency error of the terminal. Subsequently, the terminal transmits an uplink data signal to the access network device over the PUSCH. Due to the frequency correction, the maximum frequency error of the terminal is reduced. Therefore, the maximum signal bandwidth corresponding to the uplink data signal is greater than the maximum signal bandwidth corresponding to the synchronization signal.

[0226] In one design, the terminal or access network device may determine the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the first uplink signal of the terminal based on the type of the terminal. The maximum signal bandwidth of the first uplink signal is greater than the maximum signal bandwidth of the first downlink signal. In one implementation, the terminal or access network device may determine the maximum transmission bandwidth of the terminal based on the type of the terminal. For the process of determining the maximum transmission bandwidth of the terminal based on the type of the terminal and the description of the terminal type, please refer to the description in Example 1. The terminal or access network device may determine the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the first uplink signal based on the maximum transmission bandwidth of the terminal. The maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the first uplink signal are less than or equal to the maximum transmission bandwidth of the terminal.

[0227] Of course, in this embodiment of the present application, a first bandwidth set can be configured for the first downlink signal, and a second bandwidth set can be configured for the first uplink signal. The maximum signal bandwidth in the first bandwidth set is referred to as the maximum signal bandwidth of the first downlink signal, and the maximum signal bandwidth in the second bandwidth set is referred to as the maximum signal bandwidth of the first uplink signal. In one description, the first bandwidth set and the second bandwidth set can be configured based on the maximum transmission bandwidth of the terminal. Of course, any signal bandwidth included in the first bandwidth set and the second bandwidth set must be less than or equal to the maximum transmission bandwidth of the terminal.

[0228] In one implementation, the access network device and the terminal each perform the following process: determining the maximum transmission bandwidth of the terminal based on the type of the terminal. Determining the first bandwidth set and the second bandwidth set based on the maximum transmission bandwidth of the terminal, etc. It is understandable that at this time, the first bandwidth set and the second bandwidth set determined by the access network device and the terminal each need to protect the same. Alternatively, the access network device may perform the above process to determine the first bandwidth set and the second bandwidth set. The access network device configures or indicates the first bandwidth set and the second bandwidth set to the terminal. Alternatively, the terminal may perform the above process, and the terminal reports the first bandwidth set and the second bandwidth set to the access network device, etc. It is understandable that: the above description of determining the first bandwidth set and the second bandwidth set based on the maximum transmission bandwidth of the terminal can be replaced by: determining the maximum signal bandwidth of the first downlink signal and the maximum signal bandwidth of the first uplink signal based on the maximum transmission bandwidth of the terminal.

[0229] In one design, the terminal may report its type to the access network device. For example, the terminal may send a message to the access network device that includes the terminal type. This message is not limited. For details on the specific reporting process, see the description in Example 2.

[0230] In the fourth embodiment, the maximum signal bandwidths configured for the uplink and downlink signals are different. For example, the maximum signal bandwidth of the uplink signal is greater than the maximum signal bandwidth of the downlink signal. Compared to configuring the same maximum signal bandwidth for both uplink and downlink signals, this can improve uplink signal transmission efficiency and frequency domain resource utilization.

[0231] It is understandable that in the embodiments of the present application:

[0232] 1. In addition to focusing on describing the differences between different processes, the descriptions of different processes can refer to each other.

[0233] 2. In the processes of Figures 2, 3, and 4, the order of the different steps is not limited. In addition, each process may include fewer steps or more steps than the process diagrams or text descriptions.

[0234] 3. The processes in Figures 2, 3, and 4 are described using a terminal and access network device as examples. It should be understood that in each process, the terminal's functions can be implemented by the terminal itself or by a module within the terminal (e.g., a chip or circuit). The functions of the access network device can be implemented by the access network device itself or by a module within the access network device (e.g., a chip or circuit), or by a logical node, logical module, or software that fully or partially implements the access network device's functions.

[0235] 4. In the embodiments of the present application, "(e.g., a terminal) receives a signal from (e.g., an access network device)" can be understood as the source of the signal being the access network device and the destination being the terminal, which may include the terminal directly or indirectly receiving the signal from the access network device. The signal may undergo necessary processing between the source and destination, such as format changes, but the destination can still understand the valid signal from the source. Similar expressions in this application should be understood similarly and will not be repeated here.

[0236] 5. The solutions of the embodiments of the present application can be applied not only to scenarios where a terminal communicates with access network equipment, but also to other scenarios. For example, in one design, the solutions of the embodiments of the present application can be applied to scenarios where a backscatter terminal communicates with a target device. The target device can be a reader, a helper, or a series of devices that can excite the backscatter terminal. Optionally, the reader or helper device can be deployed in the access network equipment. For example, the target device is a reader, and the backscatter terminal is a tag. The reader and tag can communicate directly. For example, the reader can send an excitation signal to the tag. In response to the excitation signal, the tag can send a backscatter signal to the reader. The backscatter signal carries the tag's electronically encoded information. The reader can obtain the tag's electronically encoded information based on the backscatter signal. In this design, the excitation signal sent by the reader to the tag can be considered a downlink signal, and the backscatter signal sent by the tag to the reader can be considered an uplink signal. Alternatively, to increase the range of RFID, an exciter can be provided between the tag and the reader. For example, the reader can send a control signal to the exciter, and the exciter sends an excitation signal to the tag according to the control signal. The tag sends a backscatter signal to the reader according to the excitation of the excitation signal. In this design, the control signal sent by the reader to the exciter and the excitation signal sent by the exciter to the tag can be called a downlink signal, and the backscatter signal sent by the tag to the reader can be called an uplink signal. Alternatively, in another design, the solution of the embodiment of the present application can be applied to the scenario where a backscatter terminal communicates with a traditional terminal. The signal sent by the traditional terminal to the backscatter terminal can be called a downlink signal, and the signal sent by the backscatter terminal to the traditional terminal is called an uplink signal.

[0237] 6. The terminals in [Example 1] to [Example 4] may be IoT terminals. Due to the limited power consumption of IoT terminals, the modulation methods that can be used for downlink signals include, but are not limited to: on-off keying (OOK), amplitude shift keying (ASK), frequency shift keying (FSK), or sequence modulation based on orthogonal frequency division multiplexing (OFDM). The modulation methods that can be used for uplink signals include, but are not limited to: OOK, ASK, FSK, binary phase shift keying (BPSK), differential BPSK, minimum frequency shift keying (MSK), Gaussian minimum frequency shift keying (GMSK), or continuous phase modulation (CPM). The signal formats that can be used for uplink signals include, but are not limited to: single-carrier signal, multi-carrier signal, single-tone signal, or single-tone signal based on OFDM.

[0238] 7. In the description of this article, for a terminal capable of generating an uplink carrier signal, its frequency error is the carrier frequency error, while for a terminal capable of reflecting a downlink carrier signal but not generating an uplink carrier signal, its frequency error is the signal frequency error.

[0239] In the description herein, a terminal capable of reflecting downlink carrier signals but not generating uplink carrier signals may also be referred to as a terminal capable only of reflecting downlink carrier signals, a terminal capable only of generating uplink carrier signals, a terminal capable only of generating uplink carrier signals, or a terminal capable only of backscattering. In the description herein, a terminal capable of generating uplink carrier signals may also be referred to as a terminal capable of generating uplink carrier signals.

[0240] In the embodiments provided above, the methods provided in the embodiments of the present application are described from the perspective of the interaction between the access network device and the terminal. In order to implement the various functions in the methods provided in the embodiments of the present application, the access network device or terminal, etc., may include a hardware structure and / or a software module, and implement the above functions in the form of a hardware structure, a software module, or a hardware structure plus a software module. Whether a certain function of the above functions is executed in the form of a hardware structure, a software module, or a hardware structure plus a software module depends on the design constraints of the specific application of the technical solution.

[0241] Figures 6 and 7 are schematic diagrams of possible devices provided in embodiments of the present application. These communication devices can implement the functions of the access network device or terminal in the above-mentioned method embodiments. Therefore, it is possible to achieve the beneficial effects of the above-mentioned method embodiments.

[0242] As shown in FIG. 6 , the communication device 600 includes a processing unit 610 and an interface unit 620 .

[0243] For example, the processing unit 610 may also be referred to as a processor, a processing board, a processing module, a processing device, etc. The interface unit 620 may also be referred to as a transceiver, a transceiver, a transceiver module, a transceiver device, a communication unit, etc. Furthermore, the interface unit 620 may include at least one of a transmitting unit and a receiving unit. The transmitting unit and the receiving unit may be integrated together or two independent units.

[0244] In one design, communication apparatus 600 is configured to implement the functionality of the terminal or access network device in FIG. 2 :

[0245] For example, when the communication device 600 is used to implement the function of the terminal in Figure 2: the processing unit 610 is used to determine the maximum transmission bandwidth of the terminal under the first channel bandwidth and the first subcarrier spacing, and under the first channel bandwidth and the first subcarrier spacing, the maximum transmission bandwidth of the terminal is associated with the type of the terminal, and the first channel bandwidth includes the maximum transmission bandwidth and the minimum protection bandwidth; the interface unit 620 is used to transmit signals with the access network device according to the maximum transmission bandwidth of the terminal.

[0246] When the communication device 600 is used to implement the functions of the access network device in Figure 2: the processing unit 610 is used to determine the maximum transmission bandwidth of the terminal under the first channel bandwidth and the first subcarrier spacing, and under the first channel bandwidth and the first subcarrier spacing, the maximum transmission bandwidth of the terminal is associated with the type of the terminal, and the first channel bandwidth includes the maximum transmission bandwidth and the minimum protection bandwidth; the interface unit 620 is used to transmit signals with the terminal according to the maximum transmission bandwidth of the terminal.

[0247] In one design, communication apparatus 600 is configured to implement the functionality of the terminal or access network device in FIG. 3 :

[0248] For example, when the communication device 600 is used to implement the functions of the terminal in Figure 3: the interface unit 620 is used to send a first uplink signal to the access network device on a first uplink channel; the interface unit 620 is also used to send a second uplink signal to the access network device on a second uplink channel, where the maximum signal bandwidth of the second uplink signal is greater than the maximum signal bandwidth of the first uplink signal. Optionally, the processing unit 610 is used to generate the first uplink signal and the second uplink signal.

[0249] When the communication device 600 is used to implement the functions of the access network device in Figure 3: the interface unit 620 is configured to receive a first uplink signal from a terminal on a first uplink channel; the interface unit 620 is further configured to receive a second uplink signal from the terminal on a second uplink channel, wherein the maximum signal bandwidth of the second uplink signal is greater than the maximum signal bandwidth of the first uplink signal. Optionally, the processing unit 610 is configured to process the first uplink signal and the second uplink signal.

[0250] In one design, communication apparatus 600 is configured to implement the functionality of the terminal or access network device in FIG. 4 :

[0251] For example, when the communication device 600 is used to implement the functions of the terminal in Figure 4: the interface unit 620 is configured to receive a first downlink signal from an access network device on a first downlink channel; the interface unit 620 is further configured to receive a second downlink signal from the access network device on a second downlink channel, wherein the maximum signal bandwidth of the second downlink signal is greater than the maximum signal bandwidth of the first downlink signal. Optionally, the processing unit 610 is configured to process the first downlink signal and the second downlink signal.

[0252] When the communication device 600 is used to implement the functions of the access network device in Figure 4: the interface unit 620 is configured to send a first downlink signal to a terminal on a first downlink channel; the interface unit 620 is further configured to send a second downlink signal to the terminal on a second downlink channel, wherein the maximum signal bandwidth of the second downlink signal is greater than the maximum signal bandwidth of the first downlink signal. Optionally, the processing unit 610 is configured to generate the first downlink signal and the second downlink signal.

[0253] In one design, communication apparatus 600 is configured to implement the functionality of the terminal or access network device in FIG. 5 :

[0254] For example, when the communication device 600 is used to implement the functions of the terminal in Figure 5: the interface unit 620 is configured to receive a first downlink signal from an access network device on a first downlink channel; the interface unit 620 is further configured to transmit the first uplink signal to the access network device on a first uplink channel. The maximum signal bandwidth of the first uplink signal is greater than the maximum signal bandwidth of the first downlink signal. Optionally, the processing unit 610 is configured to generate the first uplink signal and / or process the first downlink signal.

[0255] When the communication device 600 is used to implement the functions of the access network device in Figure 5: the interface unit 620 is configured to send a first downlink signal to a terminal on a first downlink channel. The interface unit 620 is also configured to receive a first uplink signal from the terminal on a first uplink channel. The maximum signal bandwidth corresponding to the first uplink signal is greater than the maximum signal bandwidth corresponding to the first downlink signal. Optionally, the processing unit 610 is configured to generate the first downlink signal and / or process the first uplink signal.

[0256] For a more detailed description of the processing unit 610 and the interface unit 620, reference may be made to the description in the above method embodiment, which will not be repeated here.

[0257] It is understood that the division of units in the embodiments of the present application is schematic and is only a logical functional division. In actual implementation, there may be other division methods. In addition, the various functional units in the embodiments of the present application can be integrated into a physical device (for example, a processor), or each functional unit can be a separate physical device, or two or more units can be integrated into a unit for implementation. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional modules.

[0258] Figure 7 shows another schematic diagram of the structure of a communication device 700 provided in an embodiment of the present application. For example, the communication device 700 shown in Figure 7 can be a hardware circuit implementation of the communication device 600 shown in Figure 6. For ease of illustration, Figure 7 only shows the main parts of the communication device.

[0259] As shown in Figure 7, the communication device 700 includes a processor 710 and an interface circuit 720. The processor 710 and the interface circuit 720 are coupled to each other.

[0260] For example, the processor 710 may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor. The interface circuit 720 may be a transceiver or an input / output circuit, etc.

[0261] Optionally, the communication device 700 may further include a memory 730 for storing instructions executed by the processor 710, or storing input data required by the processor 710 to execute instructions, or storing data generated after the processor 710 executes instructions. For example, instructions may also be referred to as computer programs, or computer program codes, etc.

[0262] For example, the memory 730 can be a random access memory (RAM), a flash memory, a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a register, a hard disk, a mobile hard disk, a CD-ROM, or any other form of storage medium known in the art.

[0263] When the communication device 700 is used to implement the method of the terminal or access network device in Figure 2, Figure 3, Figure 4 or Figure 5, the processor 710 is used to implement the function of the processing unit 610, and the interface circuit 720 is used to implement the function of the interface unit 620.

[0264] In one design, the interface circuit 720 is used to receive signals from other communication devices outside the communication device 700 and transmit them to the processor 710, or to send signals from the processor 710 to other communication devices outside the communication device. The processor 710 uses logic circuits or executes code instructions to implement the functions of the terminal or access network device in Figures 2, 3, 4 or 5 above.

[0265] An embodiment of the present application also provides a communication device, which includes a processor and a memory, the processor and the memory being coupled, and the processor being used to implement the functions of the terminal or access network device in Figure 2, Figure 3, Figure 4 or Figure 5. For example, the processor can execute instructions in the memory so that the communication device implements one or more functions in the above-mentioned method embodiments, such as the functions implemented by the terminal or access network device in Figure 2, Figure 3, Figure 4 or Figure 5. In an exemplary embodiment, a storage medium is coupled to the 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 the storage medium can be located in an ASIC. In addition, the ASIC can be located in the terminal or access network device in Figure 2, Figure 3, Figure 4 or Figure 5. The processor and the storage medium can also exist as discrete components in the terminal or access network device in Figure 2, Figure 3, Figure 4 or Figure 5, etc.

[0266] An embodiment of the present application also provides a communication device, which includes a processor, and the processor is used to implement the functions of the terminal or access network device in Figure 2, Figure 3, Figure 4 or Figure 5.

[0267] The present application also provides a computer-readable storage medium that stores instructions, which may also be referred to as a computer program, computer program code, etc. The instructions are executed on a computer, causing the computer to perform the functions of the terminal or access network device in FIG. 2 , FIG. 3 , FIG. 4 , or FIG. 5 in the above method embodiments.

[0268] Optionally, the computer may be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user device, or other programmable device. The computer program or instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program or instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired or wireless method. The computer-readable storage medium may be any available medium that can be accessed by a computer, or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; an optical medium, such as a digital video disc; or a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or non-volatile storage medium, or may include both volatile and non-volatile types of storage media.

[0269] The present application also provides a computer program product, including a computer program or instructions. When the computer program or instructions are executed on a computer, the method of the terminal or access network device in Figures 2, 3, 4, or 5 is executed. For example, the computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on the computer, the process or function of the terminal or access network device in Figures 2, 3, 4, or 5 of the present application is fully or partially executed.

[0270] It is understood that the methods in the embodiments of the present application can be implemented in whole or in part by software, hardware, firmware, or any other combination. When implemented by software, they can be implemented in whole or in part in the form of a computer program product.

[0271] An embodiment of the present application further provides a chip, comprising a processor coupled to a memory, the processor being configured to execute computer programs or instructions stored in the memory, so that the chip implements the functions of a terminal or access network device in FIG2 , FIG3 , FIG4 , or FIG5 . For example, taking the example of a chip implementing the functions of an access network device, the chip can receive information from other modules of the access network device (such as a radio frequency or antenna, etc.), and the information can be information sent by the terminal to the access network device. Alternatively, the chip can send information to other modules in the access network device (such as a radio frequency or antenna, etc.), and the information can be information sent by the access network device to the terminal, etc.

[0272] An embodiment of the present application further provides a communication system, including: a first device and a second device.

[0273] Among them, the first device can implement the function of the terminal in Figure 2 above; the second device can implement the function of the access network device in Figure 2 above. Alternatively, the first device can implement the function of the terminal in Figure 3 above; the second device can implement the function of the access network device in Figure 3 above. Alternatively, the first device can implement the function of the terminal in Figure 4 above; the second device can implement the function of the access network device in Figure 4 above. Alternatively, the first device can implement the function of the terminal in Figure 5 above; the second device can implement the function of the access network device in Figure 5 above. For the specific structure of the first device or the second device, please refer to the previous description, such as the structural description in Figure 6 or Figure 7.

[0274] In the description of this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. In the text description of this application, the character " / " generally indicates that the previous and next associated objects are in an "or" relationship; "including at least one of A, B or C" can mean: including A; including B; including C; including A and B; including A and C; including B and C; including A, B and C.

[0275] The various numbers used in the embodiments of this application are for ease of description and are not intended to limit the scope of the embodiments of this application. The order of the sequence numbers of the above processes does not necessarily indicate the order in which they are executed. The order in which the processes are executed should be determined by their functions and internal logic.

[0276] Obviously, those skilled in the art may make various changes and modifications to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include these modifications and variations.

Claims

1. A method for determining bandwidth, characterized in that: include: Under a first channel bandwidth and a first subcarrier spacing, determine a maximum transmission bandwidth of a terminal, where under the first channel bandwidth and the first subcarrier spacing, the maximum transmission bandwidth of the terminal is associated with a type of the terminal, and the first channel bandwidth includes the maximum transmission bandwidth and a minimum protection bandwidth; Signal transmission is performed with access network equipment according to the maximum transmission bandwidth of the terminal.

2. The method according to claim 1, characterized in that The types of the terminal include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not generating an uplink carrier signal.

3. The method according to claim 2, characterized in that The terminals capable of generating uplink carrier signals include terminals whose maximum frequency error is equal to X, and terminals whose maximum frequency error is greater than X, where X is a non-negative number.

4. The method according to claim 3, characterized in that The X is equal to 0.1 parts per million ppm.

5. The method according to any one of claims 2 to 4, characterized in that The maximum transmission bandwidth corresponding to the terminal capable of generating an uplink carrier signal is greater than the maximum transmission bandwidth corresponding to the terminal capable of reflecting a downlink carrier signal but not generating an uplink carrier signal.

6. The method according to any one of claims 3 to 5, characterized in that The maximum transmission bandwidth corresponding to the terminal whose maximum frequency error is equal to X is greater than the maximum transmission bandwidth corresponding to the terminal whose maximum frequency error is greater than X.

7. The method according to any one of claims 1 to 6, characterized in that The maximum transmission bandwidth of the terminal includes a maximum downlink transmission bandwidth of the terminal and a maximum uplink transmission bandwidth of the terminal, and the maximum uplink transmission bandwidth of the terminal is greater than the maximum downlink transmission bandwidth of the terminal.

8. A method for determining bandwidth, characterized in that: include: Under a first channel bandwidth and a first subcarrier spacing, determine a maximum transmission bandwidth of a terminal, where under the first channel bandwidth and the first subcarrier spacing, the maximum transmission bandwidth of the terminal is associated with a type of the terminal, and the first channel bandwidth includes the maximum transmission bandwidth and a minimum protection bandwidth; Signal transmission is performed with the terminal according to the maximum transmission bandwidth of the terminal.

9. The method according to claim 8, characterized in that The types of the terminal include: a terminal capable of generating an uplink carrier signal, or a terminal capable of reflecting a downlink carrier signal but not generating an uplink carrier signal.

10. The method according to claim 9, characterized in that The terminals capable of generating uplink carrier signals include terminals whose maximum frequency error is equal to X, and terminals whose maximum frequency error is greater than X, where X is a non-negative number.

11. The method according to claim 10, characterized in that The X is equal to 0.1 parts per million ppm.

12. The method according to any one of claims 9 to 11, characterized in that The maximum transmission bandwidth corresponding to the terminal capable of generating an uplink carrier signal is greater than the maximum transmission bandwidth corresponding to the terminal capable of reflecting a downlink carrier signal but not generating an uplink carrier signal.

13. The method according to any one of claims 10 to 12, characterized in that The maximum transmission bandwidth corresponding to the terminal whose maximum frequency error is equal to X is greater than the maximum transmission bandwidth corresponding to the terminal whose maximum frequency error is greater than X.

14. The method according to any one of claims 8 to 13, characterized in that The maximum transmission bandwidth of the terminal includes a maximum downlink transmission bandwidth of the terminal and a maximum uplink transmission bandwidth of the terminal, and the maximum uplink transmission bandwidth of the terminal is greater than the maximum downlink transmission bandwidth of the terminal.

15. A device, characterized in that: include: A unit for implementing the method according to any one of claims 1 to 7.

16. A device, characterized in that: The device comprises a processor configured to execute instructions so that the device performs the method according to any one of claims 1 to 7.

17. A device, characterized in that: The device comprises a processor and an interface circuit, wherein the interface circuit is used to receive signals from other devices outside the device and transmit them to the processor or send signals from the processor to other devices outside the device, and the processor is used to implement the method as described in any one of claims 1 to 7 through a logic circuit or executing code instructions.

18. A device, characterized in that: include: A unit for implementing the method according to any one of claims 8 to 14.

19. A device, characterized in that: The device comprises a processor configured to execute instructions so that the device performs the method according to any one of claims 8 to 14.

20. A device, characterized in that: It includes a processor and an interface circuit, wherein the interface circuit is used to receive signals from other devices outside the device and transmit them to the processor or send signals from the processor to other devices outside the device, and the processor is used to implement the method as described in any one of claims 8 to 14 through logic circuits or execution code instructions.

21. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and the instructions are executed on a computer to enable the computer to perform the method according to any one of claims 1 to 7, or the method according to any one of claims 8 to 14.

22. A computer program product, characterized in that The device comprises a computer program or an instruction. When the computer program or the instruction is executed by the device, the method according to any one of claims 1 to 7 is executed, or the method according to any one of claims 8 to 14 is executed.

23. A chip, characterized in that: The chip comprises a processor, which is coupled to a memory and is used to execute a computer program or instruction stored in the memory, so that the chip implements the method of any one of claims 1 to 7, or the method of any one of claims 8 to 14.

24. A system, characterized in that: include: a first device and a second device; Wherein, the first device is used to implement the method according to any one of claims 1 to 7; The second device is used to implement the method according to any one of claims 8 to 14.

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