CN109716819B

CN109716819B - Channel control method and equipment

Info

Publication number: CN109716819B
Application number: CN201780056000.5A
Authority: CN
Inventors: 韩云博; 丁志明
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2016-12-19
Filing date: 2017-03-29
Publication date: 2021-06-29
Anticipated expiration: 2037-03-29
Also published as: WO2018113127A1; CN109716819A

Abstract

A method for controlling channels and equipment are provided, wherein the method is applied to first equipment, a broadband used by the first equipment comprises N non-overlapping sub-channels, and the N sub-channels are all narrow-band channels; the method comprises the following steps: the first device sends a switching channel message carrying a second sub-channel indication to a second device on a first sub-channel, where the switching channel message is sent on the first sub-channel, and the second sub-channel is a new sub-channel allocated by the first device to the second device and used for switching the second device to the second sub-channel; the first sub-channel and the second sub-channel belong to the N non-overlapping sub-channels and are different from each other; and the first device receives an acknowledgement message of the channel switching message sent by the second device on the second sub-channel, wherein the acknowledgement message is used for the first device to confirm that the second device is switched to the second sub-channel. To the characteristics of WiFi IoT.

Description

Channel control method and equipment

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a channel control method and device.

Background

With the evolution of Wireless Local Area Network (WLAN) standards, the Institute of Electrical and Electronics Engineers (IEEE) 802.11 working group is currently planning the research and formulation of Wireless Fidelity (WiFi) standards that are dominated by Internet of things (IoT) scenarios and are highly compatible with the Legacy 802.11(Legacy 802.11 protocols, such as 802.11b/a/g/n/ac) protocols. The WiFi standard may be done in 802.11ax or stand alone, but has not yet been confirmed. The popular wireless fidelity internet of things (WiFi IoT) is used in the embodiments of the present invention to refer to such an IoT scenario-dominated WiFi protocol.

In the conventional 802.11 protocol, an Access Point (AP) detects a channel when starting up, and selects a 20MHz channel with less interference as a primary 20MHz channel, on which a message interaction between a Station (STA) and the AP is to be performed. The 20MHz primary channel, once selected, is typically not changed by the AP. Since WiFi uses free spectrum, the available frequency band resources are relatively limited. For example, in china, there are only 3 non-overlapping 20MHz frequency bands at 2.4GHz, and 4 non-adjacent 20MHz frequency bands at 5GHz, so that no matter which frequency band is selected by the AP as the primary 20MHz channel, it is easy to select a completely or partially overlapping channel with a peripheral Basic Service Set (BSS).

One of the core features of WiFi IoT is to use Narrowband (NB) to transmit narrowband messages. Another core feature of WiFi IoT is that the number of narrowband IoT STAs associated with an AP may be high in some scenarios. However, with the conventional 802.11 protocol, the characteristics of WiFi IoT cannot be accommodated.

Disclosure of Invention

The technical problem to be solved by the embodiments of the present invention is to provide a channel control method and device, so as to adapt to the characteristics of WiFi IoT.

In a first aspect, an embodiment of the present invention provides a channel control method, which is applied to a first device, where the first device supports a wideband and a narrowband as bandwidths for message transmission, and the wideband used by the first device includes N non-overlapping subchannels, where the N subchannels are narrowband channels; the method comprises the following steps:

the first device sends a switching channel message carrying a second sub-channel indication to a second device on a first sub-channel, where the switching channel message is sent on the first sub-channel, and the second sub-channel is a new sub-channel allocated by the first device to the second device and used for switching the second device to the second sub-channel; the first sub-channel and the second sub-channel belong to the N non-overlapping sub-channels and are different from each other;

and the first device receives an acknowledgement message of the channel switching message sent by the second device on the second sub-channel, wherein the acknowledgement message is used for the first device to confirm that the second device is switched to the second sub-channel.

In this embodiment, since N refers to the number of subchannels, N should be an integer greater than or equal to 1; the broadband and the narrowband are relative concepts, in the embodiment, the broadband has a wider frequency range, and the narrowband has a narrower frequency range; for example, the wide band may be 20MHz or wider, the narrow band may be 2MHz or 5MHz, etc.; in addition, the first device is a device performing channel management, and may generally be an access device, for example: access points, base stations, etc.; the second device can be a terminal device, a monitoring device and the like; the second device and the second sub-channel are not limited in number in this embodiment, and therefore the second device may include 1 or more than 1 physical device, and the second sub-channel may also be 1 or more than 1 sub-channel; it is understood that if the second device only contains 1 physical device, the second sub-channel, if containing 1 sub-channel, will be to assign one sub-channel to the physical device, and if multiple sub-channels, will provide the physical device with the right to select from the multiple sub-channels; if the second sub-channel includes more than 1 sub-channel, all the physical devices included in the second device will be allocated with the same sub-channel, and if the second sub-channel includes more than 1 sub-channel, all the physical devices included in the second device may be allocated with different sub-channels.

The second channel indication is information for informing the second device of the second channel, and may generally be an identifier of the second channel, or any other information capable of indicating the second channel.

In the embodiment of the invention, because the allocation and switching of the narrowband channel are realized, the problems that severe collision is easy to occur, the channel quality changes cannot be switched, the channel resources are insufficient and the like caused by scheduling only aiming at the wideband channel in the traditional 802.11 protocol can be solved, and therefore, the scheme of the embodiment of the invention can be suitable for the characteristics of WiFi IoT.

In an optional implementation, the method further includes:

the switching channel message is sent in the process that the first device and the second device establish association by using the first sub-channel;

or, the switch channel message is sent under the condition that the first device performs load balancing.

The load balancing means that: in the above N sub-channels, when the devices associated with the sub-channels are unbalanced, the devices in the sub-channels associated with more devices need to be switched to the sub-channels associated with less devices, so as to implement the process of the devices with less difference in the number of associated sub-channels.

The scheme of the embodiment of the invention can be applied to initial distribution of the sub-channel and can also be applied to load balancing in the later period.

In an alternative implementation, the wideband has a bandwidth of 20MHz or more than 20 MHz; the narrow band has a bandwidth below 20 MHz.

In this embodiment, the N subchannels, that is, the N narrow bands, may be different from each other or may be the same, for example: all narrow bands of 2MHz, but also: 2MHz, 5MHz, or other coexistence scenarios. The maximum bandwidth may be, which depends on the spectrum resource and the protocol specification, and this is not limited by the embodiment of the present invention.

In an optional implementation manner, before the sending, to the second device on the first subchannel, a handover channel message carrying a second subchannel indication, the method further includes:

the first equipment allocates a second sub-channel for the second equipment according to the channel allocation strategy;

the channel allocation strategy comprises any one of the following strategies:

the first device randomly selects a subchannel for the second device from the N non-overlapping subchannels as the second subchannel;

or, the first device selects 1 of the subchannels from the least used subchannels as the second subchannel;

or, the first device selects 1 subchannel from the subchannels with the best signal-to-noise ratio as the second subchannel.

In this embodiment, the random allocation manner is based on the view of probability, and finally, load balancing is achieved, so that the random allocation manner is suitable for initial subchannel allocation. By counting all the entity devices using the same sub-channel, if the sub-channel is used less, the sub-channel is idle, the possibility of collision is low, the entity devices can be migrated from other sub-channels, and the newly added entity devices can be allocated to the idle sub-channel; therefore, the load balancing can be realized and the collision can be reduced by timely adjusting. The sub-channels are allocated according to the magnitude of the signal-to-noise ratio, so that the change of the communication quality between the devices caused by the movement of the devices or other reasons can be considered, and better communication quality can be obtained by adjustment.

In an optional implementation, the method further includes:

the second sub-channel is a sub-channel of M sub-channels of the N non-overlapping sub-channels, and the M sub-channels are a set of sub-channels used by a group where the second device is located.

In this embodiment, the selectable range of the second sub-channel is limited, and the selection of any of the N sub-channels is not limited, which may provide conditions for grouping of devices.

It is to be understood that M subchannels are within N subchannels, and thus M is less than or equal to N, and further M is used to indicate the number of subchannels, and thus should be an integer greater than or equal to 1.

In an optional implementation, the method further includes:

and the intersection of the M sub-channels and the set of target sub-channels is empty, and the set of target sub-channels is the set of sub-channels used by the group with the overlapping area with the group where the second device is located.

In this embodiment, since the intersection of the M sub-channels and the set of target sub-channels is empty, there will be no identical sub-channel between the group in which the second device is located and the group in which the second device has an overlapping region, and the collision of devices in different groups will be limited to a completely acceptable range.

In this embodiment, the set of subchannels may have a certain coverage area geographically, and then there may be an overlapping area between the coverage area and the coverage area; thus, the above-mentioned overlapping area indicates an overlapping area of the coverage areas.

In an alternative implementation, the grouping of the second device includes:

and classifying according to the service or the geographic position of the second equipment.

In this embodiment, the devices may be classified according to the service or the geographic location, taking the geographic location classification as an example: the geographic location may be a sector transmitted by an antenna of the access device, and the use of different sets of subchannels between different sectors reduces the likelihood of collisions between different sectors and facilitates planning the distribution of subchannels in a geographic region.

In an optional implementation manner, the second device includes 1 or more than 1 physical device, and the second sub-channel includes 1 or more than 1 sub-channel.

In the foregoing embodiment, the relationship between the number of physical devices and the number of sub-channels has already been described, and will not be described herein again.

In an optional implementation, the method further includes:

the switching channel message is a single-user switching channel message, and is used for switching a sub-channel used by the second device including 1 entity device;

or, the switching channel message is a multi-user switching channel message, and is used to switch a sub-channel used by the second device including 1 or more than 1 entity devices.

In the present embodiment, based on the relationship between the number of physical devices and the number of sub-channels described above, the content of the user switching channel message may be modified accordingly.

In an optional implementation, the method further includes:

the switching channel message also carries the second device identifier and the second sub-channel corresponding to the second device identifier, and the second device includes more than 1 entity device.

In this embodiment, especially when the second device includes a plurality of entity devices, the sub-channel corresponding to the identifier is specified, so that it is more convenient to control the sub-channel to which the specific device is switched.

In an optional implementation, the method further includes:

the switching channel message also carries a time indication that the second device sends the acknowledgement message of the switching channel message, and is used for indicating the time that the second device sends the acknowledgement message of the switching channel message;

or the switching channel message instructs the second device to send the confirmation message of the switching channel message at the default time of the first device.

In this embodiment, the sending time of the acknowledgment message is indicated by the switching channel message, so that the second device can obtain an accurate time for sending the acknowledgment message, and it is ensured that the acknowledgment message can be correctly received by the first device.

In a second aspect, an embodiment of the present invention further provides a channel control device, which is applied to a first device, where the first device supports a wideband and a narrowband as bandwidths for message transmission, and the wideband used by the first device includes N non-overlapping subchannels, where the N subchannels are narrowband channels; the channel control apparatus includes:

a sending unit, configured to send a switching channel message carrying a second sub-channel indication to a second device on a first sub-channel, where the switching channel message is sent on the first sub-channel, and the second sub-channel is a new sub-channel allocated by the first device to the second device, and is used to switch the second device to the second sub-channel; the first sub-channel and the second sub-channel belong to the N non-overlapping sub-channels and are different from each other;

a receiving unit, configured to receive, on the second subchannel, an acknowledgement message of the channel switching message sent by the second device, where the acknowledgement message is used by the first device to confirm that the second device has been switched to the second subchannel.

In an alternative implementation form of the present invention,

the sending unit is specifically configured to send the handover channel message in a process that the first device and the second device establish association using the first subchannel; or, the switching channel message is sent in case the first device performs load balancing.

In an optional implementation manner, the channel control device further includes:

a channel allocation unit, configured to allocate a second subchannel to the second device according to a channel allocation policy;

the channel allocation strategy comprises any one of the following strategies:

randomly selecting a subchannel for the second device from the N non-overlapping subchannels as the second subchannel;

or, selecting 1 subchannel from the least used subchannels as the second subchannel;

or, selecting 1 subchannel from the subchannels with the best signal-to-noise ratio as the second subchannel.

In an optional implementation manner, the second sub-channel is a sub-channel of M sub-channels of the N non-overlapping sub-channels, and the M sub-channels are a set of sub-channels used by a group where the second device is located.

In an optional implementation manner, an intersection of the M sub-channels and a set of target sub-channels is null, and the set of target sub-channels is a set of sub-channels used by a group having an overlapping area with a group in which the second device is located.

In an alternative implementation, the grouping of the second device includes: and classifying according to the service or the geographic position of the second equipment.

In an optional implementation manner, the handover channel message is a single-user handover channel message, and is used to switch a sub-channel used by the second device including 1 entity device;

In an optional implementation manner, the handover channel message further carries the second device identifier and the second sub-channel corresponding to the second device identifier, where the second device includes more than 1 entity device.

In an optional implementation manner, the switching channel message further carries a time indication that the second device sends an acknowledgement message of the switching channel message, and is used to indicate a time that the second device sends the acknowledgement message of the switching channel message;

In a third aspect, an embodiment of the present invention further provides a channel allocation and handover communication method, used in a first device, where the method includes:

the first device supports at least the use of 20MHz and below 20MHz bandwidths as the bandwidth for message transmission; the first device has N non-overlapping sub-channels under a 20MHz bandwidth, wherein the N sub-channels are all channels below 20MHz, and N is a positive integer;

the first device sends a channel switching message to the one or more second devices on the first sub-channel according to the group where the one or more second devices are located, wherein the channel switching message is sent on the first sub-channel and carries one or more new sub-channels allocated by the first device to the one or more second devices according to a channel allocation strategy, and the one or more new sub-channels are used for switching the one or more second devices to the one or more new sub-channels; the first subchannel is one of the N non-overlapping subchannels, the first subchannel and the one or more new subchannels being different channels;

the first device receives, on the one or more new sub-channels, acknowledgement messages of the channel switching messages sent by the one or more second devices, respectively, so that the one or more second devices acknowledge to the first device that the channel is switched to the one or more new sub-channels;

the channel allocation policy includes at least one of:

the first device randomly selects one or more subchannels for the one or more second devices from the N non-overlapping subchannels as the one or more new subchannels;

or, the first device selects one or more sub-channels from the least used sub-channels in the group in which the one or more second devices are located as the one or more new sub-channels, and each group uses at least one sub-channel;

or, the first device selects one or more sub-channels from the sub-channels with the best signal-to-noise ratio in the packet in which the one or more second devices are located as the one or more new sub-channels.

In a WiFi IoT scenario, there may be multiple narrowband IoT channels available for selection and use under the AP's primary 20MHz channel, and how the AP allocates the narrowband IoT channels used for the associated narrowband IoT STAs may have an impact on the performance of the WiFi system. Through a reasonable channel allocation strategy, the performance of the whole WiFi system can be improved. Additionally, the AP sends a channel switching message to multiple narrowband IoT STAs, which can switch the narrowband IoT STAs to the same or different new channels, thereby improving the channel utilization efficiency and saving air interface resources.

In an optional implementation, the method further includes:

the first device selects M of the N non-overlapping subchannels from the channel allocation policy; the first device selecting one of the M non-overlapping subchannels as the one or more new subchannels to be used by the one or more second devices; wherein M is a positive integer no greater than N.

Assuming that the AP can allocate one of N narrowband IoT channels as a new channel for a narrowband IoT STA, the AP may select M of the N narrowband IoT channels for STAs in a certain group as new channels allocable for the STAs in the group, where M is a positive integer no greater than N. The benefit is that narrowband IoT STAs in two adjacent BSSs that are geographically adjacent or overlap in coverage may effectively reduce interference between the two adjacent BSSs if they use different narrowband IoT channels.

In an optional implementation, the method further includes:

the M non-overlapping subchannels used by the one or more second devices in the different groups are not identical.

Here is a mixed policy in the channel allocation policy in the embodiment of the present invention, that is, STAs in different groups may be allocated with different narrowband IoT channels, which increases the flexibility of the channel allocation policy.

In an optional implementation, the method further includes:

if the first device sends the switching channel message to the second device, the switching channel message is a single-user switching channel message used for switching the sub-channel used by the second device;

if the first device sends the switching channel message to the second devices, the switching channel message is a multi-user switching channel message and is used for switching sub-channels used by the second devices.

The single user switch channel message is used to switch the narrowband IoT channel used by the single narrowband IoT STA; the multi-user switching channel message is used to switch the narrowband IoT channels used by the multiple narrowband IoT STAs, where the narrowband IoT channels originally used by the multiple narrowband IoT STAs need to be the same, and the new narrowband IoT channels after switching may be the same or different. The multi-user channel switch message is more flexible than the conventional 802.11 protocol in which the STAs are all switched to the same channel.

In an optional implementation, the method further includes:

the channel switching message also carries the identifiers of the one or more second devices, and is used for indicating that the one or more second devices need to switch to the one or more new sub-channels.

When multiple narrowband IoT STAs need to switch to multiple new narrowband IoT channels, identification information (such as MAC address, AID, or the like) of the narrowband IoT STAs needs to be indicated in the multi-user switching channel message for indicating which narrowband IoT STAs are to switch to which new narrowband IoT channels.

In an optional implementation, the method further includes:

the switching channel message carries a time indication that the one or more second devices send the acknowledgement message of the switching channel message, and is used for indicating the one or more second devices to send the acknowledgement message of the switching channel message at a preset time.

In order to avoid collision between acknowledgement messages of the multi-user switching channel message replied by the plurality of narrowband IoT STAs and to cause the AP to be unable to determine which narrowband IoT STAs sent the acknowledgement message of the multi-user switching channel message, the AP may add a preset time for the plurality of narrowband IoT STAs to send the acknowledgement message of the multi-user switching channel message to the multi-user switching channel message, so that the AP may acknowledge which narrowband IoT STAs successfully switch to a new channel.

In an optional implementation, the method further includes:

the switch channel message instructs the one or more second devices to send an acknowledgement message of the switch channel message at a time agreed upon by default with the first device.

The narrowband IoT STA can reply with the confirmation message of the switching channel message at the time agreed by default with the AP, which has the advantage of saving overhead because the narrowband IoT STA does not need to be instructed in the switching channel message to send the time of the confirmation message of the switching channel message.

In a fourth aspect, an embodiment of the present invention further provides another channel allocation and handover communication method, where the method is used for a first device, and the method includes:

the first device and the second device use a first sub-channel to establish association, and in the process of establishing association, the first device sends a switching channel message to the second device on the first sub-channel according to a group where the second device is located, wherein the switching channel message is sent on the first sub-channel and carries the first device to allocate a new sub-channel to the second device according to a channel allocation policy, so that the second device is switched to the new sub-channel; the new sub-channel is one of the N non-overlapping sub-channels, and the first sub-channel and the new sub-channel are different channels;

the first device receives an acknowledgement message of the channel switching message sent by the second device on the new sub-channel, so that the second device confirms to the first device that the channel is switched to the new sub-channel;

the channel allocation policy includes at least one of:

the first device randomly selects a sub-channel for the second device from the N non-overlapping sub-channels as the new sub-channel;

or, the first device selects a subchannel from the least used subchannels in the packet in which the second device is located as the new subchannel, and each packet uses at least one subchannel;

or, the first device selects a sub-channel from the sub-channels with the best signal-to-noise ratio in the packet in which the second device is located as a new sub-channel.

In an optional implementation, the method further includes:

the first device selects M of the N non-overlapping subchannels from the channel allocation policy; the first device selects one of the M non-overlapping sub-channels as a new sub-channel used by the second device; wherein M is a positive integer no greater than N.

In an optional implementation, the method further includes:

the M non-overlapping subchannels used by the second device in the different group are not identical.

In an optional implementation, the method further includes:

the switching channel message carries a time indication for the second device to send the acknowledgement message of the switching channel message, and is used for indicating the second device to send the acknowledgement message of the switching channel message at a preset time.

In an optional implementation, the method further includes:

the switching channel message instructs the second device to send a confirmation message of the switching channel message at a time agreed by default with the first device.

In a fifth aspect, an embodiment of the present invention further provides a first device, where the first device includes:

a transceiver supporting at least a bandwidth using 20MHz and a bandwidth below 20MHz as a bandwidth for message transmission; the transceiver has N non-overlapping sub-channels under a 20MHz bandwidth, wherein the N sub-channels are all channels under 20MHz, and N is a positive integer; the method includes that a first device sends a switching channel message to one or more second devices on a first sub-channel, the switching channel message is sent on the first sub-channel, carries one or more new sub-channels allocated by the first device to the one or more second devices according to a channel allocation strategy, and is used for switching the one or more second devices to the one or more new sub-channels;

a transceiver, further configured to receive, by the first device, an acknowledgement message of the switch channel message sent by the one or more second devices on the one or more new sub-channels, for the one or more second devices to acknowledge to the first device that the switch has been made to the one or more new sub-channels;

a processor for generating the switching channel message and analyzing a confirmation message of the switching channel message;

a processor further configured to select the one or more new subchannels for the one or more second devices according to a channel allocation policy; the channel allocation policy includes at least one of:

a processor that randomly selects one or more subchannels for the one or more second devices from the N non-overlapping subchannels as the one or more new subchannels;

or, the processor selects one or more sub-channels from the least used sub-channels in the packets in which the one or more second devices are located as the one or more new sub-channels, and each packet uses at least one sub-channel;

or, the processor selects one or more sub-channels with best signal-to-noise ratio from the sub-channels in the packet in which the one or more second devices are located as the one or more new sub-channels;

a memory for storing program code and instructions; and further for storing the channel allocation policy;

an antenna for transceiving messages from a wireless medium.

In an optional implementation manner, in the channel allocation strategy, the first device selects M non-overlapping subchannels from the N non-overlapping subchannels; the first device selecting one of the M non-overlapping subchannels as the one or more new subchannels to be used by the one or more second devices; wherein M is a positive integer no greater than N.

In an alternative implementation, the M non-overlapping subchannels used by the one or more second devices in the different groups are not identical.

In an optional implementation manner, if the first device sends the channel switching message to the second device, the channel switching message is a single-user channel switching message used for switching a sub-channel used by the second device;

In an optional implementation manner, the handover channel message further carries an identifier of the one or more second devices, which is used to indicate that the one or more second devices need to handover channels to the one or more new sub-channels.

In an optional implementation manner, the switching channel message further carries a time indication that the one or more second devices send the acknowledgment message of the switching channel message, and is used to instruct the one or more second devices to send the acknowledgment message of the switching channel message at a preset time.

In an alternative implementation, the switch channel message indicates that the one or more second devices reply to the switch channel message with an acknowledgement message at the first device at a default agreed time.

In a sixth aspect, an embodiment of the present invention further provides a wireless communication device, used as a first device, including: an input-output device, a processor, and a memory; the memory can be used for providing a cache required by the processor for data processing or other data storage requirements; the input and output device provides the capability of communication between the access device and the second device; the processor is used for realizing the control of the method flow provided by the embodiment of the invention.

In a seventh aspect, an embodiment of the present invention further provides a wireless communication device, used as a first device, including: an input-output device, a processor, and a memory; wherein the memory stores program instructions and the processor is configured to implement the method flow provided by the embodiments of the present invention during execution of the program instructions.

Drawings

In order to more clearly illustrate the technical solution in the embodiment of the present invention, the drawings required to be used in the embodiment of the present invention will be described below.

FIG. 1 is a diagram of a sub-channel of Legacy equipment at 20MHz according to an embodiment of the present invention;

FIG. 2 is a diagram of a sub-channel of a Legacy device at 20MHz according to an embodiment of the present invention;

fig. 3 is a schematic diagram of allocation of a narrowband IoT channel in an embodiment of the invention;

FIG. 4 is a diagram illustrating the result of randomly allocating narrowband channels according to an embodiment of the present invention;

FIG. 5 is a diagram illustrating the result of allocating a narrowband channel according to an embodiment of the present invention;

fig. 6 is a schematic diagram of allocation of narrowband channels according to the group of STAs according to the embodiment of the present invention;

fig. 7 is a schematic diagram of restricting STA selectable narrowband IoT channel allocation according to an embodiment of the present invention;

fig. 8 is a schematic diagram of a restricted STA selectable narrowband IoT channel allocation in conjunction with a packet according to an embodiment of the present invention;

fig. 9 is a narrowband IoT channel allocation signaling diagram of a single STA in an embodiment of the present invention;

fig. 10 is a narrowband IoT channel allocation signaling diagram of a single STA in an embodiment of the present invention;

fig. 11 is a narrowband IoT channel allocation signaling diagram of a single STA in an embodiment of the present invention;

fig. 12 is a schematic structural diagram of a wireless communication device according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram of a channel control device according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of a channel control device according to an embodiment of the present invention;

FIG. 15 is a schematic structural diagram of a first apparatus according to an embodiment of the present invention;

fig. 16 is a schematic structural diagram of a wireless communication device according to an embodiment of the present invention.

Detailed Description

The embodiments of the present invention will be described below with reference to the drawings.

One of the core features of WiFi IoT is to use Narrowband (NB) to transmit narrowband messages, such as 1MHz, 2MHz, or 5MHz as the base bandwidth, and the narrowband IoT devices and legacy (legacy) devices may use the same spectrum.

The above narrowing is compared to the conventional WLAN supporting 802.11 using 20MHz as the base bandwidth; a narrowband IoT device refers to a device that uses narrowband transmission and is dominated by an IoT scenario; legacy devices refer to legacy 802.11 devices that use bandwidths of 20MHz and above; the same spectrum may be as follows: 2.4GHz, 5GHz, etc.

In a WiFi IoT scenario, considering factors such as demand and cost, an Access Point (AP) side device is likely to support 20MHz and narrowband IoT transmissions simultaneously. In embodiments of the present invention, Legacy + narrowband IoT APs will be used to refer to such devices in the following sections. As shown in fig. 1, the 20MHz primary channel occupancy spectrum of the Legacy + narrowband IoT AP is a dashed rectangle that may be subdivided into N narrowband IoT channels. The narrowband IoT channels may also be referred to herein as subchannels, such as solid-line rectangular regions; assuming that the narrowband IoT channel bandwidth is 2MHz, one possible subdivision is to divide the 20MHz primary channel into 9 2MHz narrowband channels, i.e., N is 9, and the remaining spectrum in 20MHz is used as the guard bandwidth.

The 20MHz primary channel refers to a 20MHz channel which is used by Legacy devices by default for listening to WiFi signals. It should be noted that the bandwidths of the N narrowband IoT channels may or may not be all the same. A Station (Station, STA) may then support only narrowband IoT transmissions or both 20MHz and narrowband IoT transmissions. The aforementioned bandwidths of the N narrowband IoT channels may be identical, such as all 2MHz channels; the bandwidths of the aforementioned N narrowband IoT channels may not be all the same, such as 4 2MHz channels, 2 5MHz channels, and so on. The above-mentioned STA in the embodiment of the present invention may refer to all STAs supporting 802.11 protocol, including STAs supporting conventional 802.11 protocol, i.e., legacy STAs; and STAs that support narrowband IoT transmissions, namely narrowband IoT STAs. If only narrowband IoT transmissions are supported, it may be referred to as a narrowband IoT STA; if supporting both 20MHz and narrowband IoT transmissions, it may be referred to as legacy + narrowband IoT STA. It should be noted that the cost of a STA supporting both 20MHz and narrowband IoT transmissions is much greater than supporting only narrowband IoT transmissions, so WiFi IoT STAs with stronger low cost requirements are likely to support only narrowband IoT transmissions.

Another core feature of WiFi IoT is that the number of narrowband IoT STAs associated with an AP may be high in some scenarios. In meter reading and meter reading scenarios, a building or an entire cell may be associated with thousands of narrowband IoT STAs under the same AP. The association refers to that the STA joins a Basic Service Set (BSS) in which the AP is located, and the STA can transmit and receive messages with the AP only after joining the BSS. In such a scenario, due to a wide coverage area of a cell, STAs in opposite directions may not receive signals of each other, and meanwhile, the number of nodes is large, and contention conflicts and other problems may be very prominent. The contention conflict refers to a situation where multiple STAs may simultaneously transmit WiFi messages, resulting in mutual interference between the STAs. Therefore, there is a mechanism similar to Group Sectorization Operation in such protocols, and the core idea is to divide the whole BSS into several areas (called sectors, or groups), and the AP uses directional antennas to time-share and alternately align to each sector. When the AP is aligned to a certain sector through the directional antenna, the STAs in the sector may transmit, and the STAs in other sectors go to sleep. That is, the above mechanism limits the number of STAs that can communicate with the AP in a certain time by multiplexing space and time.

In current 802.11 protocols (e.g., 802.11b/a/g/n/ac), an AP selects only a 20MHz primary channel over a segment of the spectrum (e.g., 2.4GHz or 5GHz), on which all STAs associated therewith transmit messages. However, in the WiFi IoT scenario, there are multiple available narrowband IoT channels under the 20MHz primary channel of the AP supporting legacy + narrowband IoT, if only one of the narrowband IoT channels is selected as the primary channel for the transmission of the narrowband IoT device (e.g., the narrowband IoT STA), on one hand, other narrowband IoT channels under the 20MHz will be wasted, and on the other hand, since the narrowband IoT STAs all use the same channel (like the narrowband IoT channel, i.e., the same sub-channel), the collision (collision) between STAs may be severe. The collision is a situation that two devices send messages at the same time, and as a result, both devices fail to send messages, and assuming that the probability of sending messages by each device is the same, the probability of collision between STAs is higher when the number of associated STAs in the same channel is higher. As shown in fig. 2, assuming that N narrowband IoT channels can be partitioned under a 20MHz primary channel, if there is only one narrowband IoT channel as the primary narrowband IoT channel of a narrowband IoT device, then resources of the remaining N-1 narrowband IoT channels will be wasted, while all narrowband IoT devices will be concentrated in the primary narrowband IoT channel. Therefore, a possible design scheme is provided in the embodiment of the present invention to allocate any narrowband IoT channel under its 20MHz primary channel to a narrowband IoT STA as its primary narrowband IoT channel for an AP supporting legacy + narrowband IoT, and the primary narrowband IoT channels of different narrowband IoT STAs may be different.

From the above introduction, the legacy 802.11 protocol cannot adapt to the WiFi IoT application scenario, at least in the following aspects:

1. in the conventional 802.11 protocol, the AP selects a channel with less current interference from current optional channels as a 20MHz primary channel, and does not consider the use condition of the channel in a longer time period.

2. The number of narrowband IoT STAs associated with an AP in a WiFi IoT scenario may be large, and since the AP may listen to multiple narrowband IoT channels (under the same 20MHz primary channel) simultaneously, the passive channel selection approach in the existing protocol is not well suited in the WiFi IoT scenario.

3. The legacy 802.11 protocol does not consider the impact on system performance of the selection of STA narrowband IoT channels after STA grouping.

4. Once an AP selects a 20MHz primary channel in the legacy 802.11 protocol, its associated STAs all transmit messages on the 20MHz primary channel. However, there are multiple narrowband IoT channels available in the WiFi IoT scenario, so the AP needs to have a corresponding mechanism to cause different STAs to schedule to different narrowband IoT channels.

Based on the foregoing description, the STAs associated with the AP in the Legacy 802.11 protocol are all on the same 20MHz primary channel, and the Legacy + narrowband IoT AP in the WiFi IoT scenario can simultaneously listen to its 20MHz primary channel and multiple narrowband IoT channels overlapping with the frequency band. If the AP only uses one of the narrowband IoT channels as a primary narrowband IoT channel for narrowband IoT transmission, that is, all narrowband IoT devices associated with the AP use the same primary narrowband IoT channel for transmission of messages, other narrowband IoT channels in the 20MHz channel are not used, resulting in a waste of resources. The embodiment of the invention can improve the collision condition (collision) of each narrow-band IoT channel and reduce the interference between the BSS and the OBSS in a WiFi IoT scene, particularly in a scene that the AP associates a large number of STAs by endowing the AP with the capability of distributing different narrow-band IoT channels for different narrow-band IoT devices. The OBSS is an adjacent BSS having an overlapping coverage area using the same channel as the BSS.

The scheme application scenario of the embodiment of the invention is summarized as follows:

how an AP allocates different STAs on different narrowband IoT channels in a WiFi IoT multi-narrowband IoT STA scenario.

Legacy + narrowband IoT APs in the present specification may support transmission of messages using 20MHz and bandwidths below 20 MHz; further, the method can also support the transmission of messages by using bandwidths above 20MHz (such as 40MHz, 80MHz, 160MHz and the like).

The embodiment of the invention relates to communication between an AP and an associated STA thereof.

In this specification, if not specifically described, the AP refers to Legacy + narrowband IoT AP and the STA refers to narrowband IoT STA in the following content, and therefore, the following embodiments will not be described in detail. In the subsequent embodiments, the AP corresponds to the first device in the foregoing embodiments, and the STA corresponds to the second device in the foregoing embodiments.

The scheme summary of the embodiment of the invention comprises the following aspects:

1. the AP maintains a narrowband IoT Channel Selection list (Narrow Band IoT Channel Selection Table) for STAs of the BSS.

2. And the AP establishes association with the STA, and allocates a proper narrowband IoT channel for the STA according to the narrowband IoT selection list and the channel allocation strategy.

3. After the AP associates with the STA, the appropriate narrowband IoT channel is adjusted for the STA according to the narrowband channel IoT selection list and the channel allocation policy.

The following examples will be described in detail with respect to the above three sections, respectively, as follows:

first, the AP maintains a narrowband IoT channel selection list for STAs of the BSS.

In this section, the AP needs to record the narrowband IoT channels used by STAs within the BSS.

One possible recording approach is for the AP to maintain a narrowband IoT channel selection list that is used to record the narrowband IoT channels used by STAs associated with the AP.

1. A possible recording manner of the narrow-band IoT channel selection list is shown in table 1, where the identifiers of different STAs in the longitudinal direction may be complete or short identifiers, such as a Medium Access Control (MAC) address, an Association Identifier (AID), and the like; the narrowband IoT channels occupied for the STA are horizontally (e.g., the narrowband IoT channels are numbered 1 to N, where N is the total number of available narrowband IoT channels for the AP). Wherein the MAC address is a unique identifier of the wireless communication device and has a length of 48 bits (bit); aid (association identifier) is a brief identifier allocated to STA by AP after association between AP and STA is established.

Table 1a list of possible narrowband IoT channel selections

STA ID	Number occupying narrowband IoT channels (1, 2, 3.., N)
		STA 1	1
STA 2	3
		STA 3	4
...	...
		STA i	3

2. Optionally, the AP obtains, through the narrowband IoT channel selection list, distribution of the number of associated STAs on each narrowband IoT channel, so that the AP determines the probability of collision (collision) between STAs on different narrowband IoT channels. If the number of STAs differs more between different narrowband IoT channels, the probability of a collision between STAs on the narrowband IoT channels on which the STAs are more distributed may be greater.

Secondly, in the stage of establishing association between the AP and the STA, the STA is allocated a suitable narrowband IoT channel according to the narrowband IoT channel information (such as the narrowband IoT channel selection list) and the channel allocation policy used by the STA that has established association with the AP. The channel allocation strategy described above will be described in the subsequent part of this embodiment.

1. A process for an AP to allocate a primary narrowband IoT channel to a STA when the AP establishes an association with the STA, as shown in fig. 3, the process includes:

first, STA1 (which is a STA) sends an Association Request message (Association Request Frame) to the AP on a default narrowband IoT channel (e.g., narrowband IoT channel m) to reply to STA1 with an Association Response message (Association Response Frame) on the same narrowband IoT channel to confirm that an Association is established.

The AP then selects an appropriate narrowband IoT channel (e.g., narrowband IoT channel l) for the newly associated STA1 according to the narrowband IoT channel selection list and the channel allocation policy, and sends a switch channel message on narrowband IoT channel m. The switch channel message at least indicates a new narrowband IoT channel, such as narrowband IoT channel l, to be used by the STA; optionally, it may also indicate when to perform channel switching, such as the STA switching to a new narrowband IoT channel 100ms after receiving the above-mentioned channel switching message.

Finally, STA1 receives the switch channel message and completes the channel switch, and sends an acknowledgement message to the AP on the new narrowband IoT channel l indicating that the channel switch has been completed.

Note that if the narrowband IoT channel that the AP plans to allocate to STA1 (e.g., narrowband IoT channel i) is the same as the narrowband IoT channel that STA1 sends the association request (e.g., narrowband IoT channel m), then the AP need not send a switch channel message to switch the channel of ST 1A; naturally, the STA need not send an acknowledgement message to acknowledge receipt of the switch channel message.

2. One possible signaling interaction procedure for the AP to allocate the narrowband IoT channel to the STA is as follows:

2A, STA requests association with the AP, sending an association request message to the AP on narrowband IoT channel m (CH m).

The narrowband IoT channel m may be a narrowband IoT channel that is used by default when the AP establishes an association with the STA. For example, there are multiple narrowband IoT channels under the 20MHz primary channel used by the AP, and the AP selects one of the narrowband IoT channels m as a narrowband IoT channel that is used by default when the AP associates with the STA; or, there are multiple narrowband IoT channels under the 20MHz primary channel used by the AP, and the AP may associate with the STA on all or part (more than one) of the multiple narrowband IoT channels, where the narrowband IoT channel m is one of all or part of the multiple narrowband IoT channels.

2B, AP receives the association request message sent by the STA on the narrowband IoT channel m, and replies an association response message to the STA to acknowledge receipt of the association request message.

2C, AP selects a suitable narrowband IoT channel for the STA according to the narrowband IoT channel information (e.g., the narrowband channel IoT selection list) and the channel allocation policy used by the STA as the narrowband IoT channel for subsequent message transmission. If the narrowband IoT channel is different from the narrowband IoT channel m currently used by the STA, the AP sends a switching channel message to the STA to switch the narrowband IoT channel used by the STA. The switch channel message indicates at least a new narrowband IoT channel to be used by the STA; optionally, it may also indicate when to perform a channel switch.

In the embodiment of the present invention, the above channel allocation policy is used to allocate the newly associated STA to a certain narrowband IoT channel, so that the performance of at least a certain aspect of the WiFi system may be improved. The performance of the WiFi system includes, but is not limited to, collision probability between STAs, Signal to Noise Ratio (SNR) on the narrowband IoT channel, Signal to Interference plus Noise Ratio (SINR), and the like.

The SNR is a ratio of the power of the useful signal to the power of the noise, and the SINR is a ratio of the power of the useful signal to the power of the interference signal plus the noise, wherein the larger the ratio of the power of the useful signal to the power of the interference signal plus the power of the noise, the better the ratio is, which indicates that the quality of the useful signal received by the receiving end is better. Both the SNR and SINR described above are affected by the wireless propagation medium.

Possible channel allocation policies include one or more of the following channel allocation policies:

and (4) randomly distributing.

Such as the AP randomly selecting one of N selectable narrowband IoT channels to allocate to the STA. This channel allocation strategy has the advantage of simplicity, the end STAs will be evenly distributed across the different narrowband IoT channels based on a probability perspective. However, the number of associated STAs on the narrowband IoT channels may be different, so that the collision probability between STAs on some narrowband IoT channels is high, and the performance of the WiFi system is adversely affected. As shown in fig. 4, after the above randomly allocated channel allocation strategy is adopted, the number of STAs associated on the narrowband IoT channel CH2 and CH N-1 is large, which results in a high probability of collision between STAs using the two narrowband IoT channels.

Secondly, selecting a narrowband IoT channel with the least number of associated STAs to be allocated to the STAs according to the number of the STAs associated with each narrowband IoT channel.

For example, the AP obtains information about the number of associated STAs on each channel according to the narrow-band channel IoT selection list, and selects a narrow-band IoT channel with the smallest number of associated STAs to allocate to the STA. If there are channels with the least number of associated STAs, one of the associated STAs is randomly selected to be allocated to the newly associated STA. The benefit of this channel allocation strategy is that the number of associated STAs on each narrowband IoT channel is very balanced, and there is no significant difference in collision probability among the channels. The drawback is that the AP needs to obtain statistics of the narrowband IoT channel associated STAs, slightly increasing the computational load of the AP. As shown in fig. 5, the number of associated STAs on each narrowband IoT channel is relatively uniform, and thus the collision probability between STAs of different narrowband IoT channels may not be very different.

And thirdly, allocating a narrowband IoT channel with the best SNR or SINR to the STA according to the SNR or SINR of the associated narrowband IoT channel.

If the AP associates with the STA, the AP allocates a narrowband IoT channel with the best SNR or SINR to the STA. The benefit is that the quality of the messages transmitted by the STA on the narrowband IoT channel in a short time after association may be better than that of the messages transmitted by other narrowband IoT channels, but considering a longer time scale, since the wireless propagation media of the narrowband IoT channels may change, the transmission of wireless signals may be influenced positively or negatively, and it is difficult to predict whether the narrowband IoT channel is still the narrowband IoT channel with the best SNR or SINR after a longer time scale. That is, the narrowband IoT channel allocated to the STA by the AP at the time of association may no longer be the channel with the best SNR or SINR after a period of time.

And fourthly, allocating the narrow-band IoT channel according to the grouping of the STAs.

The grouping refers to the AP grouping STAs of the BSS into groups according to certain characteristics of the STAs, for example, grouping the STAs into a plurality of groups according to the traffic, geographical location, and other factors of the STAs.

As shown in fig. 6, one example of a possible allocation policy is: the AP allocates a narrowband IoT channel to the STAs according to the group in which the STAs are located, for example, all STAs in a certain group use the same narrowband IoT channel, and STAs in different groups may use different narrowband IoT channels (e.g., all STAs in sector 1 use narrowband IoT channel CH1, and all STAs in sector 2 use narrowband IoT channel CH 2).

And fifthly, limiting the selectable narrow-band IoT channels of the STA.

For example: the AP chooses a narrowband IoT channels from the N available narrowband IoT channels, from which all the narrowband IoT channels allocated for the newly associated STA are chosen. That is, the narrowband IoT channels that all STAs associated with the AP can use are concentrated on the a narrowband IoT channels. The above a narrowband IoT channels may be selected by the AP from the a least interfering narrowband IoT channels after startup. The benefit is that if the Overlapping Basic Service Set (OBSS) AP also takes a similar strategy, i.e. the OBSS AP chooses B narrowband IoT channels among the N available narrowband IoT channels as the alternative narrowband IoT channels allocated to the OBSS STA. If the A, B two sets of narrowband IoT channels do not overlap at all or only partially overlap, the interference between STAs of the two BSSs will be effectively reduced (i.e., the STAs of the two BSSs are not on the same narrowband IoT channel and do not generate significant interference with each other), so as to improve the efficiency of the WiFi system. The OBSS refers to an adjacent BSS that partially overlaps with the coverage area of the BSS.

As shown in fig. 7, the two BSSs in which AP1 and AP2 are located are OBSS, and the STA associated with AP1 selects one of the a narrowband IoT channels as a primary narrowband IoT channel, such as CH1, CH3, or CH 5. Assume here that STA1 is associated with AP 1. The STA associated with the AP2 selects one of the B narrowband IoT channels as a primary narrowband IoT channel, such as CH2, CH4, or CH 6. Here STA2 associates with AP 2. In this scenario, even though STA1 and STA2 are both in the overlapping region of AP1 and AP2 coverage, STA1 and STA2 do not generate meaningful interference with each other because STA1 and STA2 use different narrowband IoT channels.

And sixthly, adopting a mixing strategy, namely simultaneously using two or more of the channel strategies.

For example: the STA is restricted from selectable narrowband IoT channels while being grouped. One possible allocation strategy is for the AP to allocate optional narrowband IoT channels to the STA according to the packet in which the STA is located, that is, the AP selects a (a is greater than or equal to 1) narrowband IoT channels from N available narrowband IoT channels as the narrowband IoT channels that can be allocated to the STA in a certain packet, and the narrowband IoT channels used by all STAs in the packet are selected from the a narrowband IoT channels. As shown in fig. 8, in an IoT scenario (e.g., meter reading) that requires association of a large number of STAs, the AP divides its coverage into a plurality of sectors (e.g., L sectors) according to the geographic location, and the STAs in a certain sector are a group. For example, STA packets within sector 1 may use narrowband IoT channel CH1 or CH3, STA packets within sector 3 may use narrowband IoT channel CH2 or CH N-1, and so on. The advantage is that STAs of a certain sector collectively use one or more narrowband IoT channels, and if STAs of other BSSs that overlap with the coverage area of the sector in whole or in part use different narrowband IoT channels, the interference between STAs in the two adjacent BSSs can be effectively reduced.

2D, STA receives the switch channel message sent by the AP, switches to the new narrowband IoT channel at the appointed time, and sends an acknowledgement message of the switch channel message to the AP on the new narrowband IoT channel to indicate that it has successfully switched the channel.

The appointed time refers to that the STA switches the channel at a default time (for example, immediately, after 50ms, or after 100 ms) after receiving the channel switching message sent by the AP, or switches the channel according to the time indicated in the channel switching.

Third, after the AP associates with the STA, the AP may change the narrowband IoT channel used by a single or multiple STAs.

For a scenario where only one STA needs to adjust the narrowband IoT channel, the AP may send a single-user switch channel message on the narrowband IoT channel used by the STA to adjust the narrowband IoT channel used by the STA to a new narrowband IoT channel; for a scenario in which multiple STAs on the same narrowband IoT channel need to adjust the channel, the AP may send at least one multi-user channel switching message to adjust the narrowband IoT channels used by the multiple STAs, and the new narrowband IoT channels used by the multiple STAs may be the same new narrowband IoT channel or different new narrowband IoT channels; alternatively, the AP may send a broadcast switch channel message for switching the narrowband IoT channel used by all STAs on a certain narrowband IoT channel.

Another possible signaling interaction process for an AP to switch a narrowband IoT channel for an STA is that the AP sends a channel switching message to the STA that needs to change the channel, which will be discussed in two cases:

A. the AP changes the narrowband IoT channel used by the individual STA.

Firstly, the AP sends a single-user channel switching message on a narrow-band IoT channel used by the STA, and indicates a new narrow-band IoT channel to be used by the STA; optionally, the STA may also be instructed to switch the narrowband IoT channel at time.

Secondly, as shown in fig. 9, a procedure is provided in which after the AP associates with the STA, the AP changes the primary narrowband IoT channel of the STA (e.g., STA1) through a single-user channel switching message. The AP sends a single user switch channel message to STA1 on narrowband IoT channel m used by STA1 indicating that STA1 needs to switch to narrowband IoT channel i. STA1 switches to the narrowband IoT channel l at a preset time, and sends an acknowledgement message (e.g., ACK) of the single-user switching channel to the AP on the narrowband IoT channel l to confirm that STA1 has successfully switched to the new narrowband IoT channel. The predetermined time may be a time predetermined by the AP and the STA1 (e.g., a time specified in the 802.11 protocol, or a time preset after the AP/STA1 is produced), or a time indicated in the single-user channel switch message.

Optionally, there are other STAs (e.g., STA2) that need to switch the narrowband IoT channel, and the AP continues to send a single-user switch channel message to STA2 for switching STA2 from narrowband IoT channel m to narrowband IoT channel k. It should be noted that if the channel (e.g., narrowband IoT channel l) used by STA1 to send the acknowledgement message (e.g., ACK) of the single-user change channel message is different from the narrowband IoT channel (e.g., narrowband IoT channel m) used by the single-user change channel message sent by AP to STA2, the AP may send the single-user change channel message to STA2 without waiting for the acknowledgement message sent by STA1 for the single-user change channel.

B. The AP simultaneously changes the channels of multiple STAs on the same narrowband IoT channel.

Firstly, an AP sends a multi-user switching channel message on a narrow-band IoT channel used by a plurality of STAs, and the multi-user switching channel message carries the identifications of the STAs and a new narrow-band IoT channel to be used by the STAs; optionally, the time at which the plurality of STAs switch the narrowband IoT channel may also be indicated.

After the AP sends the multi-user channel switching message, the STAs simultaneously send a group acknowledgement message (e.g., BA, Block ACK, group acknowledgement frame) on their respective new narrowband IoT channels after the channel switching is completed, for acknowledging that the STAs have successfully switched to the new narrowband IoT channels.

As shown in fig. 10, the AP sends a multi-user switch channel message to multiple STAs (e.g., STA1, STA2, STA3, STA4, etc.) for simultaneously switching the narrowband IoT channels of the multiple STAs on a certain narrowband IoT channel (e.g., narrowband IoT channel m). The multi-user switching channel message carries the identities of the STAs that need to switch the narrowband IoT channel and the new narrowband IoT channel that the STAs will use. Like STA1, STA3, etc., will switch from narrowband IoT channel m to narrowband IoT channel i, STA2, STA4, etc., will switch from narrowband IoT channel m to narrowband IoT channel k. After the STAs switch to the new narrowband IoT channel, the STAs simultaneously send BA acknowledgements to the AP on each new narrowband IoT channel to confirm that the channel switch has been successfully completed. The above BA is used for multiple STAs to simultaneously acknowledge receipt of a message, and it is more efficient for multiple STAs to transmit acknowledgement frames (ACKs) one by one. The drawback is that if some STAs (e.g., STA3) in the plurality of STAs transmitting the BA on the same new narrowband IoT channel (e.g., STA1 and STA3 on narrowband IoT channel l) do not reply to the AP at the appointed time for some reason (e.g., STA3 does not hear the multi-user handoff channel message transmitted by the AP), but since STA1 has replied to the BA, the AP cannot distinguish who the BA originated (the BA transmitted by a single STA and the BAs transmitted by multiple STAs at the same time are all the same on the AP side), it may result in that the AP cannot recognize that STA3 has not successfully handed off the channel through the received BA.

Optionally, the multi-user switching channel message may further carry an indication of when the multiple STAs send an acknowledgement message (e.g., BA) of the multi-user switching channel message.

After the AP sends the multi-user channel switching message, the STAs send an acknowledgement message of the multi-user channel switching message to the AP at different time points of their respective new narrowband IoT channels after the channel switching is completed, so as to confirm that the AP has successfully switched to the new narrowband IoT channel. The acknowledgement message of the multiuser switching channel message may be an ACK frame.

As shown in fig. 11, the AP sends a multi-user switch channel message to multiple STAs (e.g., STA1, STA2, STA3, STA4, etc.) for simultaneously switching the narrowband IoT channels of the multiple STAs on a certain narrowband IoT channel (e.g., narrowband IoT channel m). The multi-user switching channel message carries the identities of the STAs that need to switch the narrowband IoT channel, the new narrowband IoT channel to be used by the STAs, and an indication of when the STAs send an acknowledgement message (e.g., ACK) for the multi-user switching channel message. Like STA1, STA3, etc., will switch from narrowband IoT channel m to narrowband IoT channel i, STA2, STA4, etc., will switch from narrowband IoT channel m to narrowband IoT channel k.

After the plurality of STAs are switched to the new narrowband IoT channel, the STAs respectively send ACK acknowledgements to the AP according to the appointed time to confirm that the switching of the narrowband IoT channel is successfully completed. It should be noted that ACK is used instead of BA, that is, multiple STAs on the same narrowband IoT channel transmit the acknowledgement message (i.e., ACK) of the multi-user handover channel message in a time-sharing manner. If the STA1 sends ACK to the AP at the appointed time 1 after switching the channel, the STA3 sends ACK to the AP at the appointed time 3 after switching the channel. The benefit is that the AP can determine from the received ACKs which STAs have been successful in switching to the new narrowband IoT channel.

An embodiment of the present invention provides a wireless communication device, which can implement any method embodiment provided in the embodiment of the present invention, and a specific structure of the wireless communication device may be the structure of the wireless communication device shown in fig. 12, where the module S1200 corresponds to the wireless communication device. For the wireless communication apparatus S1200, it includes sub-modules S1201, S1202, S1203, and S1204. The wireless communication device may include: a processor S1201, a memory S1202, a transceiver S1203, and an antenna S1204.

The sub-module S1201 corresponds to one or more processors, and may implement generation or parsing of a handover channel message, an acknowledgement message (e.g., ACK, BA, etc.).

The sub-module S1202 corresponds to a memory (which may be one or more) for storing program codes and transmits the stored program codes to the processor S1201.

The sub-module S1203 corresponds to a transceiver of the wireless communication device for transceiving a message. Such as a handover channel message, an acknowledgement message, etc.

The sub-module S1204 corresponds to an antenna of the wireless communication device.

It should be noted that the structures of the Legacy device, the narrowband IoT device, and the Legacy + narrowband IoT device in the embodiment of the present invention may all refer to the structure of the wireless communication device described above, where the devices include an AP and a STA. The difference between the above three is mainly in the capability of the sub-module S1203 transceiver and the sub-module S1201 processor. The processor and the transceiver of the Legacy device can only generate, analyze and transmit and receive WiFi messages at 20MHz and its integral multiple of bandwidth (such as 40MHz, 80MHz, 160MHz, etc.); the processor and transceiver of the narrowband IoT device may generate, parse, and transceive the narrowband IoT message over a bandwidth that is less than 20MHz (i.e., narrowband); the processor and transceiver of the Legacy + narrowband IoT device may generate, parse, and transceive WiFi messages at least at 20MHz and bandwidths less than 20MHz, and may further generate, parse, and transceive narrowband IoT messages at bandwidths above 20MHz (e.g., 40MHz, 80MHz, 160MHz, etc.).

When the above wireless communication device is embodied as a first device (e.g. Legacy + narrowband IoT AP in the first embodiment of the present invention):

the processor S1201 of the first device is configured to generate the switching channel message, which includes the single-user switching channel message and the multi-user switching channel message, and is configured to switch a narrowband IoT channel of a single STA or multiple STAs, where the switching channel message is a narrowband message. The processor S1201 of the first device may be further configured to allocate a narrowband IoT channel to the STA according to the channel allocation policy.

The transceiver S1203 of the first device is configured to send the above-mentioned channel switching message generated by the processor S1201.

The memory S1202 of the first device is further configured to store the narrowband IoT channel selection list.

When the wireless device is embodied as a second device (e.g., a STA in the first embodiment of the present invention):

a transceiver S1203 of the second device, configured to receive the channel switching message sent by the first device;

a processor S1201 of the second device, configured to parse the handover channel message sent by the first device; and generating a confirmation message, such as ACK or BA, of the handover channel message.

The transceiver S1203 of the second device is further configured to send an acknowledgement message, such as ACK or BA, of the above channel switching message.

The technical scheme of the embodiment of the invention has the beneficial effects that:

since the narrowband IoT primary channel used by the STA is determined once the AP selects the 20MHz primary channel in the legacy 802.11 protocol. While there may be multiple narrowband IoT channels available to choose from in a WiFi IoT scenario, the AP needs a new narrowband IoT channel allocation policy to adapt to the scenario. When the STA is associated with the AP in the embodiment of the invention, the AP allocates a reasonable narrowband IoT channel for the STA newly establishing the association by sending the switching channel message according to the narrowband IoT channel allocation list, thereby improving the performance of the WiFi system.

When the AP switches the primary 20MHz channel in the conventional 802.11 protocol, all STAs associated with the AP need to switch to the new 20MHz channel. In the WiFi IoT scenario, since there are multiple narrowband IoT channels available for switching under the primary 20MHz channel, the multiple STAs associated with the AP do not need to be all concentrated on a certain narrowband IoT channel, and therefore a new mechanism is needed to adapt to this characteristic. In the embodiment of the invention, the AP sends the multi-user channel switching message to the STA to switch a plurality of STAs on the same narrow-band IoT channel to different narrow-band IoT channels, thereby improving the channel switching efficiency and optimizing the performance of the WiFi system. The AP effectively helps the AP to know whether all STAs have successfully switched to the new narrowband IoT channel by instructing different STAs to send acknowledgement messages of the switch channel message at different agreed times in the switch channel message.

The embodiment of the invention also provides channel control equipment which is applied to first equipment, wherein the first equipment supports a broadband and a narrow band as the bandwidth for message transmission, the broadband used by the first equipment comprises N non-overlapping sub-channels, and the N sub-channels are narrow-band channels; as shown in fig. 13, the channel control apparatus includes:

a sending unit 1301, configured to send a switching channel message carrying a second sub-channel indication to a second device on a first sub-channel, where the switching channel message is sent on the first sub-channel, and the second sub-channel is a new sub-channel allocated by the first device to the second device, and is used to switch the second device to the second sub-channel; the first sub-channel and the second sub-channel belong to the N non-overlapping sub-channels and are different from each other;

a receiving unit 1302, configured to receive, on the second sub-channel, an acknowledgement message of the channel switching message sent by the second device, where the acknowledgement message is used by the first device to confirm that the second device has switched to the second sub-channel.

the sending unit 1301 is specifically configured to send the handover channel message in a process that the first device and the second device establish an association using the first subchannel; or, the switching channel message is sent when the first device performs load balancing.

In an alternative implementation, the wideband has a bandwidth of 20MHz or more than 20 MHz; the narrow band has a bandwidth of 20MHz or less.

In an alternative implementation manner, as shown in fig. 14, the channel control device further includes:

a channel allocating unit 1401, configured to allocate a second sub-channel to the second device according to a channel allocation policy;

the channel allocation strategy comprises any one of the following strategies:

randomly selecting a subchannel for said second device from said N non-overlapping subchannels as said second subchannel;

or, selecting a subchannel from the least used subchannels as the second subchannel;

or, selecting a subchannel from the subchannels with the best signal-to-noise ratio as the second subchannel.

In an optional implementation manner, an intersection of the M sub-channels and a set of target sub-channels is null, and the set of target sub-channels is a set of sub-channels used by a group having an overlapping area with the group in which the second device is located.

In an optional implementation manner, the grouping of the second device includes: and classifying according to the service or the geographic position of the second equipment.

or, the switching channel message is a multi-user switching channel message, and is used to switch a sub-channel used by the second device including 1 or more than 1 physical devices.

In an optional implementation manner, the handover channel message further carries the second device identifier and the second sub-channel corresponding to the second device identifier.

In an optional implementation manner, the handover channel message further carries a time indication that the second device sends an acknowledgement message of the handover channel message, where the time indication is used to indicate a time that the second device sends the acknowledgement message of the handover channel message;

or, the switch channel message instructs the second device to send a confirmation message of the switch channel message at a default time of the first device.

An embodiment of the present invention further provides a first device, as shown in fig. 15, where the first device includes:

a transceiver 1501 supporting at least 20MHz and a bandwidth below 20MHz as a bandwidth for message transmission; the transceiver has N non-overlapping sub-channels under a 20MHz bandwidth, wherein the N sub-channels are all channels under 20MHz, and N is a positive integer; sending, by a first device, a switch channel message to the one or more second devices on a first subchannel, where the switch channel message is sent on the first subchannel, carries one or more new subchannels allocated by the first device to the one or more second devices according to a channel allocation policy, and is used to switch the one or more second devices to the one or more new subchannels;

a transceiver 1501, further configured to receive, by the first device, an acknowledgement message of the channel switching message sent by the one or more second devices on the one or more new sub-channels, and configured to confirm to the first device that the one or more second devices have switched to the one or more new sub-channels;

a processor 1503, configured to generate the handover channel message and parse an acknowledgement message of the handover channel message;

a processor 1503 further configured to select the one or more new sub-channels for the one or more second devices according to a channel allocation policy; the channel allocation strategy at least comprises one of the following:

a processor 1503 for randomly selecting one or more subchannels for the one or more second devices from the N non-overlapping subchannels as the one or more new subchannels;

or, the processor 1503, selecting one or more sub-channels from the least used sub-channels in the packets in which the one or more second devices are located as the one or more new sub-channels, where each packet uses at least one sub-channel;

or, the processor 1503, selecting one or more of the subchannels with the best signal-to-noise ratios from the packets in which the one or more second devices are located as the one or more new subchannels;

a memory 1502 for storing program codes and instructions; the system is also used for storing the channel allocation strategy;

an antenna 1504 for transceiving messages from a wireless medium.

In an optional implementation manner, in the channel allocation strategy, the first device selects M non-overlapping subchannels from the N non-overlapping subchannels; said first device selecting one of said M non-overlapping subchannels as said one or more new subchannels to be used by said one or more second devices; wherein M is a positive integer no greater than N.

Assuming that the AP can allocate one of N narrowband IoT channels as a new channel for a narrowband IoT STA, the AP may select M of the N narrowband IoT channels as new channels allocable for STAs in a certain group, where M is a positive integer not greater than N. The benefit is that narrowband IoT STAs in two adjacent BSSs that are geographically adjacent or overlap in coverage may effectively reduce interference between the two adjacent BSSs if they use different narrowband IoT channels.

In an alternative implementation, the M non-overlapping subchannels used by the one or more second devices in different groups are not all identical.

if the first device sends the switching channel message to the second devices, the switching channel message is a multi-user switching channel message used for switching sub-channels used by the second devices.

The single user switch channel message is used to switch the narrowband IoT channel used by the single narrowband IoT STA; the multi-user switching channel message is used to switch the narrowband IoT channels used by the multiple narrowband IoT STAs, where the narrowband IoT channels originally used by the multiple narrowband IoT STAs need to be the same, and the new narrowband IoT channels after switching may be the same or different. The multi-user channel switch message is more flexible than the conventional 802.11 protocol in which the STAs are switched to the same channel.

In an optional implementation manner, the handover channel message further carries an identifier of the one or more second devices, which is used to indicate that the one or more second devices need to switch channels to the one or more new sub-channels.

In order to avoid collision between the acknowledgement messages of the multi-user switching channel message replied by the multiple narrowband IoT STAs, which results in that the AP cannot determine which narrowband IoT STAs send the acknowledgement messages of the multi-user switching channel message, the AP may add preset time for the multiple narrowband IoT STAs to send the acknowledgement messages of the multi-user switching channel message to the multi-user switching channel message, so that the AP may confirm which narrowband IoT STAs are successfully switched to a new channel.

In an alternative implementation, the switch channel message indicates that the one or more second devices reply to the confirmation message of the switch channel message at the default appointed time by the first device.

In a sixth aspect, an embodiment of the present invention further provides a wireless communication device, as shown in fig. 16, which is used as a first device, and includes: input/output devices 1601, processors 1602, and memories 1603; wherein the memory 1603 may be used to provide a cache required by the processor for data processing, or other data storage requirements; the input/output device 1601 provides the capability for communication between the access device and a second device; the processor 1602 is configured to implement the control of the method flow provided by any one of the embodiments of the present invention.

An embodiment of the present invention further provides a wireless communication device, as shown in fig. 16, which is used as a first device, and includes: input/output devices 1601, processors 1602, and memories 1603; the memory 1603 stores program instructions, and the processor 1602 is configured to implement any one of the method flows provided by the embodiments of the present invention in the process of executing the program instructions. The input/output device 1601 is used to enable communication with a second device.

The input/output device 1601, the processor 1602, and the memory 1603 may be connected to each other via a bus.

Memory 1603 includes, but is not limited to, Random Access Memory (RAM), Read-Only Memory (ROM), Erasable Programmable Read-Only Memory (EPROM), or portable Read-Only Memory (CD-ROM), where Memory 1603 is used for associated instructions and data. The input and output device 1601 is used to receive and transmit data.

The processor 1602 may be one or more Central Processing Units (CPUs), and in the case that the processor 1602 is one CPU, the CPU may be a single-core CPU or a multi-core CPU.

The relevant parts among the method embodiments of the invention can be mutually referred; the apparatus provided in the respective apparatus embodiments is adapted to perform the method provided in the respective method embodiments, so that the respective apparatus embodiments may be understood with reference to the relevant parts in the relevant method embodiments.

The names of the messages/frames, modules or units provided in the embodiments of the present invention are only examples, and other names may be used as long as the roles of the messages/frames, modules or units are the same.

It will be understood by those skilled in the art that all or part of the steps in the method for implementing the above embodiments may be implemented by instructing the relevant hardware through a program, and the program may be stored in a readable storage medium of a device, and when executed, the program includes all or part of the steps, and the storage medium may be, for example: FLASH, EEPROM, etc.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that various embodiments may be combined, and the above-mentioned embodiments are only exemplary embodiments of the present invention and are not intended to limit the scope of the present invention.

Claims

1. A channel control method is applied to a first device, the first device supports a wideband and a narrowband as message transmission bandwidths, the wideband has a bandwidth of 20MHz, the narrowband has a bandwidth below 20MHz, the wideband used by the first device includes N non-overlapping sub-channels, and the N sub-channels are all narrowband channels; the method comprises the following steps:

the first device sends a switching channel message carrying a second sub-channel indication to a second device on a first sub-channel, where the switching channel message is sent on the first sub-channel, and the second sub-channel is a new sub-channel allocated by the first device to the second device and used for switching the second device to the second sub-channel; the first sub-channel and the second sub-channel both belong to the N non-overlapping sub-channels and are different from each other, the second device includes 1 or more than 1 physical devices, the second sub-channel includes 1 or more than 1 sub-channel, and when the second sub-channel includes 1 or more than 1 physical devices, each sub-channel included in the second sub-channel corresponds to one or more physical devices included in the second device;

2. The method of claim 1, further comprising:

3. The method of claim 1, wherein before the sending the handover channel message carrying the second subchannel indication to the second device on the first subchannel, the method further comprises:

the channel allocation strategy comprises any one of the following strategies:

4. The method of claim 3, further comprising:

5. The method of claim 4, further comprising:

6. The method of claim 5, wherein the grouping of the second device comprises:

7. The method of any one of claims 1 to 6, further comprising:

or, the switching channel message is a multi-user switching channel message, and is used for switching a sub-channel used by the second device including 1 or more than 1 entity devices.

8. The method of any one of claims 1 to 6, further comprising:

the switching channel message also carries the second device identifier and the second sub-channel corresponding to the second device identifier.

9. The method of any one of claims 1 to 6, further comprising:

10. A channel control device is applied to a first device, and is characterized in that the first device supports a wideband and a narrowband as bandwidths for message transmission, the wideband has a bandwidth of 20MHz, the narrowband has a bandwidth below 20MHz, the wideband used by the first device contains N non-overlapping sub-channels, and the N sub-channels are all narrowband channels; the channel control apparatus includes:

a sending unit, configured to send a switching channel message carrying a second sub-channel indication to a second device on a first sub-channel, where the switching channel message is sent on the first sub-channel, and the second sub-channel is a new sub-channel allocated by the first device to the second device, and is used to switch the second device to the second sub-channel; the first sub-channel and the second sub-channel both belong to the N non-overlapping sub-channels and are different from each other, the second device includes 1 or more than 1 physical devices, the second sub-channel includes 1 or more than 1 sub-channel, and when the second sub-channel includes 1 or more than 1 physical devices, each sub-channel included in the second sub-channel corresponds to one or more physical devices included in the second device;

11. The channel control apparatus according to claim 10,

12. The channel control device according to claim 10, wherein the channel control device further comprises:

the channel allocation strategy comprises any one of the following strategies:

13. The channel control apparatus according to claim 12,

14. The channel control apparatus according to claim 13,

15. The channel control apparatus according to claim 14,

the grouping of the second device includes: and classifying according to the service or the geographic position of the second equipment.

16. The channel control device according to any one of claims 10 to 15,

17. The channel control device according to any one of claims 10 to 15,

18. The channel control device according to any one of claims 10 to 15,