KR101537895B1 - Method and apparatus for controlling sleep mode of wifi access point - Google Patents

Abstract

Disclosed are a sleep method for saving energy of a WiFi wireless access point and an apparatus thereof. Provided is a wireless LAN communication apparatus comprising: a memory which is loaded with at least one program; and at least one processor, wherein the processor performs the processes of: determining a sleep time to be applied to a sleep state, according to a control of the program; and controlling an on/off time of a power, according to the sleep time.

Description

[0001] METHOD AND APPARATUS FOR CONTROLLING SLEEP MODE OF WIFI ACCESS POINT [0002]

Embodiments of the present invention relate to techniques for reducing energy consumption of IEEE 802.11 wireless access points.

With the widespread adoption of Wi-Fi (IEEE 802.11 Wireless LAN), smart phones, tablets, and laptops are becoming popular and the installation of Wi-Fi access points (eg, wired / wireless routers) Is growing.

Although energy-saving methods are widely studied for base stations in cellular networks, energy-saving methods for Wi-Fi wireless access points (APs) with relatively low energy consumption have been studied I did. This is based on the policy that the AP is always on so that it can accept the terminals.

However, since the proportion of Wi-Fi APs in current network structure is significant, energy-saving issues in these Wi-Fi APs also become important issues.

In this regard, Korean Patent No. 10-1283673 (Jul. 02, 2013) entitled " Access Point Detection System and Method for Smartphone ", discloses a method for searching access points through cooperation of ZigBee and WiFi 802.11 access point detection techniques capable of reducing energy consumption are disclosed.

Provides an AP sleep method and device that can reduce the energy consumption of a Wi-Fi AP (wireless access point).

Provides an AP sleep method and device that can reduce energy consumption through power adjustment of a Wi-Fi AP.

At least one program loaded memory; And at least one processor, wherein the at least one processor is configured to: determine a sleep time to apply to a sleep state in accordance with a control of the program; And controlling a power on / off time according to the sleep time.

According to an aspect of the present invention, the controlling step may control power supplied to the communication module.

According to another aspect, the determining step may determine the sleep time according to a traffic transmission amount and a traffic delay requirement.

According to another aspect, the controlling step may maintain the power off during the sleep period for each beacon interval, which is a period for transmitting a beacon signal.

According to another aspect, the controlling step may maintain the power on during an awake time existing between the sleep time and the sleep time.

According to another aspect, the determining process may determine the minimum sleep time and the maximum sleep time according to the traffic transmission amount and the traffic delay requirement.

According to another aspect of the present invention, the determining includes determining a minimum value and a maximum value that can be a sleep time when the expected packet delay for the traffic transmission amount is equal to or less than the traffic delay requirement is the minimum sleep time and the maximum sleep time A value corresponding to one half of a minimum value and a maximum value that can be taken as the sleep time when the expected packet delay for the traffic transmission amount exceeds the traffic delay requirement is divided into the minimum sleep time and the maximum sleep time You can decide.

According to another aspect of the present invention, the controlling step maintains the power off state during the sleep period for each beacon period, which is a period for transmitting a beacon signal, The sleep time can be gradually increased.

According to another aspect, the controlling step may increase the beacon interval to a time exceeding the sleep time when the sleep time exceeds the beacon interval.

According to another aspect of the present invention, the controlling step may determine whether a transmission packet or a reception packet exists before increasing the sleep time, and may increase the sleep time if the transmission packet or the reception packet does not exist.

According to another aspect, the controlling step may maintain the power on during an awake time existing between the sleep time and the sleep time.

A wireless communication unit; And a control unit for determining a sleep time using the traffic transmission amount and the traffic delay requirement and for maintaining the consumed power of the wireless communication unit in the sleep state during the sleep time.

A communication apparatus in an IEEE 802.11 environment, comprising: a frame transmitting a beacon signal for notifying a terminal having mobility to a location of the beacon; And maintains the consumed electric power of the communication device in a sleep state.

A sleep control method performed in a wireless LAN communication apparatus, the method comprising: determining a sleep time using a traffic transmission amount and a traffic delay requirement of the wireless LAN communication apparatus; And maintaining the power consumption of the wireless communication module of the wireless LAN communication device in the sleep state during the sleep time.

According to an embodiment of the present invention, the energy of the Wi-Fi AP can be effectively reduced by applying a sleep mode through power adjustment of the Wi-Fi AP.

1 and 2 are block diagrams illustrating an internal configuration of a Wi-Fi AP capable of reducing energy consumption in an embodiment of the present invention.
3 is an exemplary diagram for explaining a sleep operation of a Wi-Fi AP in an embodiment of the present invention.
4 is a flowchart illustrating a sleep control method of a Wi-Fi AP capable of reducing energy consumption according to an exemplary embodiment of the present invention.
5 is a flowchart illustrating an algorithm for determining a minimum value and a maximum value of the sleep time in an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention proposes a technique for effectively reducing the energy consumption of a Wi-Fi AP by gradually setting a minimum value and a maximum value of a sleep time in consideration of a data traffic state and a traffic delay requirement in a Wi-Fi AP environment do.

1 is a block diagram illustrating an internal configuration of a Wi-Fi AP capable of reducing energy consumption in an embodiment of the present invention.

Referring to FIG. 1, a terminal (e.g., a smartphone, a tablet, etc.) 101 continuously searches for an 802.11 channel in order to find a Wi-Fi AP 100 according to mobility in an 802.11 infrastructure. The wireless Internet basically assumes the mobile situation, and the AP search according to the movement is an essential element for the wireless communication.

In the present invention, a sleep mode may be applied to the Wi-Fi AP 100 in order to save energy of the Wi-Fi AP 100.

1, a Wi-Fi AP 100 according to an embodiment may include a wireless communication unit 110, a wired communication unit 120, and a controller 130.

The wireless communication unit 110 is composed of a radio frequency (RF) antenna for communicating with a station (STA). At this time, the radio antenna can transmit, receive, and transmit-receive three types.

The wired communication unit 120 is a wired part connected to the outside, and it is possible to have three types of transmission, reception, and transmission-reception.

The controller 130 is responsible for all operations of the Wi-Fi AP 100 and may include a sleep boundary decision (SBD) operation module 131 and a sleep control module 132 .

At this time, the SBD operation module 131 obtains the minimum value and the maximum value of the time to be wiped by the Wi-Fi AP 100, and the sleep control module 132 actually controls the power on / off of the RF communication unit 110 (on / off) time.

The SBD operation module 131 and the sleep control module 132 may be implemented by hardware or software.

The energy saving effect can be achieved by keeping the power consumption of at least one of the wireless communication unit 110 and the wired communication unit 120, which are the communication terminals of the Wi-Fi AP 100, in the sleep state.

However, among the components of the Wi-Fi AP 100, the wired communication unit 120 can use the inherent energy saving mode, and the controller 130 must maintain the power supply state at all times. Therefore, in the present embodiment, the sleep mode can be applied through the power adjustment (on / off) of the wireless terminal, that is, the wireless communication unit 110, in order to reduce the energy consumption of the Wi-Fi AP 100.

2, the SBD operation module 131 reads the traffic transmission amount and the traffic delay requirement to be processed from the memory in which the traffic is stored, reads the minimum delay time T _min through the read information, And the maximum slip time (T _max ).

In order to reduce the energy consumption of the Wi-Fi AP 100, the sleep control module 132 gradually increases the minimum sleep time T _min and the maximum sleep time T _max calculated in the SBD operation module 131 The sleep mode can be controlled while the sleep time of the wireless communication unit 110 is increased.

3 is a diagram for explaining a basic operation of the Wi-Fi AP 100. As shown in FIG.

Generally, the Wi-Fi AP 100 transmits a beacon signal with a beacon interval as a period. At this time, the beacon signal is a signal used to inform the mobile terminal of the existence and location of the Wi-Fi AP 100, and the beacon interval defined in the standard is 100 ms.

In the present invention, the Wi-Fi AP 100 gradually increases the sleep time from the minimum sleep time ( _Tmin ) to the maximum sleep time ( _Tmax ) for each beacon interval. At this time, if the sleep time exceeds the beacon interval, the beacon interval is increased more than the time exceeded and the sleep state is entered. For example, if the sleep time exceeds the initial beacon interval, the amount of time that is at least twice the time exceeded in the initial beacon interval can be increased. The increasing time C _i can be determined by increasing the starting value (T _min ) by a factor of two (ie, C _i = 2 ⁱ ), the most commonly used method in a wireless environment.

There is an awake time between the sleep times to check whether there is traffic to be processed or not.

4 is a flowchart illustrating a sleep control method of a Wi-Fi AP capable of reducing energy consumption according to an exemplary embodiment of the present invention. The sleep control method according to one embodiment may be performed by the Wi-Fi AP described in FIG. 1 through FIG.

In step S401, the Wi-Fi AP may calculate a minimum sleep time T _min and a maximum sleep time T _max using a sleep boundary decision (SBD) algorithm.

In step S402 to step S404, the Wi-Fi AP sets the initial sleep time T ₀ as the minimum sleep time T _min and enters the sleep mode for a predetermined sleep time T ₀ .

In step S405 to step S406, the Wi-Fi AP switches to the active mode by the listen interval when the sleep time set in the sleep mode passes, and confirms whether there is a packet to be sent or received.

In step S407 and step S403, if there is no packet to be sent or received, the Wi-Fi AP increments the initial sleep time T ₀ by the predetermined time C ₁ to set the next sleep time T ₁ , And repeats the processes (S404 to S406). The sleep mode can be applied while gradually increasing the sleep time until the sleep time becomes the maximum sleep time T _max which is the last sleep time T _n .

Meanwhile, if there is a packet to be sent or received, the Wi-Fi AP can resume the sleep mode by initializing the sleep time to the initial sleep time (T ₀ ) which is the minimum sleep time (T _min ) after transmitting or receiving the packet .

Figure 5 is a flow chart illustrating an algorithm for calculating a minimum sleep time (T _min ) and a maximum sleep time (T _max ), in an embodiment of the present invention.

First, in step S510, the Wi-Fi AP calculates an expected packet delay D for a traffic transmission amount to be currently processed, and then determines whether the expected packet delay D satisfies a packet delay requirement D _req ) it does not exceed the maximum value that can have a sleep time (T _{max_th)} the maximum sleep time (T _max) (i.e., T _max T == _{max_th)} as crystals, estimated packet delay (D), the packet delay requirement (D _req) has to be determined when the one-half of the maximum value (T _{max_th)} which may have a sleep time to the maximum sleep time (T _{max) (i.e., T max == T max_th / 2} ) is exceeded.

In step S520, the Wi-Fi AP sets a minimum value (T _{min - th} ) that can be taken as the sleep time if the expected packet delay (D) does not exceed the packet delay requirement (D _req ) the minimum sleep time (T _min) (i.e., T _min == _{min_th} T) and to determine the minimum value of expected packet delay (D) is exceeded the packet delay requirement (D _req) can have a sleep time (T _{min_th} Can be determined as the minimum slip time T _min (i.e., T _min == T _{min - th} / 2).

The above algorithm is executed every time the packet delay requirement D _req is changed, and the efficiency can be increased by dynamically adjusting the minimum sleep time T _min and the maximum sleep time T _max . However, since the minimum slip time _Tmin and the maximum slip time _Tmax can not be infinitely increased, it is necessary to set the maximum value of each value. At this time, the maximum value that can be the minimum sleep time (T _min ) is T _{min - th} and the maximum value that can be the maximum sleep time (T _max ) is T _{max - th} .

와 같이 정해질 수 있다. 예를 들어, 최대 슬립 시간(T_max)의 초기 값이 32이고 최대 슬립 시간(T_max)의 최대 값(T_{max_th})이 512이면 최대 슬립 시간(T_max)은 32, 64, 128, 256, 512 순으로 증가하게 된다.Assuming C _j = 2 ^j , the maximum slip time (T _max ) can be gradually increased through T _max = min (2j × T _max , T _{max - th} ). That is, the maximum slip time (T _max )

. ≪ / RTI > For example, the maximum sleep time (T _max) the initial value is 32 and the maximum up to the sleep time (T _max) 512 is (T _{max_th)} of the maximum sleep time (T _max) of the 32, 64, 128, 256, 512, respectively.

As described above, according to the embodiment of the present invention, the energy consumption of the Wi-Fi AP can be reduced by applying the sleep mode through power adjustment of the Wi-Fi AP. The Wi-Fi AP sleeping technology according to the present invention can be widely applied according to the number of Wi-Fi APs which are rapidly increasing in terms of a communication service provider.

The apparatus described above may be implemented as a hardware component, a software component, and / or a combination of hardware components and software components. For example, the apparatus and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA) , A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing unit may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device , Or may be permanently or temporarily embodied in a transmitted signal wave. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

101:
100: Wi-Fi AP

Claims (14)

At least one program loaded memory; And
At least one processor
Lt; / RTI >
Wherein the at least one processor, under control of the program,
Determining a sleep time for applying to a sleep state; And
Controlling the power on / off time in accordance with the sleep time
Lt; / RTI >
Wherein the determining comprises:
The minimum sleep time and the maximum sleep time are determined according to the traffic transmission amount and the traffic delay requirement,
Determining a minimum value and a maximum value that can be a sleep time as the minimum sleep time and the maximum sleep time if the expected packet delay for the traffic transmission amount is equal to or less than the traffic delay requirement,
And determining a value corresponding to one half of a minimum value and a maximum value that can be taken as the sleep time as the minimum sleep time and the maximum sleep time when the expected packet delay for the traffic transmission amount exceeds the traffic delay requirement
The wireless LAN communication apparatus comprising: The method according to claim 1,
Wherein the controlling step comprises:
Controlling the power supplied to the communication module
The wireless LAN communication apparatus comprising: delete The method according to claim 1,
Wherein the controlling step comprises:
Maintaining the power source in an off state during the sleep time for each beacon interval that is a period for transmitting a beacon signal
The wireless LAN communication apparatus comprising: 5. The method of claim 4,
Wherein the controlling step comprises:
Maintaining the power supply in an on state during an awake time present between the sleep time and the sleep time
The wireless LAN communication apparatus comprising: delete delete At least one program loaded memory; And
At least one processor
Lt; / RTI >
Wherein the at least one processor, under control of the program,
Determining a sleep time for applying to a sleep state; And
Controlling the power on / off time in accordance with the sleep time
Lt; / RTI >
Wherein the determining comprises:
The minimum sleep time and the maximum sleep time are determined according to the traffic transmission amount and the traffic delay requirement,
Wherein the controlling step comprises:
Keeping the power supply in an off state during the sleep period for each beacon interval that is a period for transmitting a beacon signal, and gradually increasing the sleep time from the minimum sleep time to the maximum sleep time
The wireless LAN communication apparatus comprising: 9. The method of claim 8,
Wherein the controlling step comprises:
And increasing the beacon interval to a time exceeding the sleep time when the sleep time exceeds the beacon interval
The wireless LAN communication apparatus comprising: 9. The method of claim 8,
Wherein the controlling step comprises:
Before increasing the sleep time, it is determined whether there is a transmission packet or a reception packet, and if the transmission packet or the reception packet does not exist, the sleep time is increased
The wireless LAN communication apparatus comprising: 9. The method of claim 8,
Wherein the controlling step comprises:
Maintaining the power supply in an on state during an awake time present between the sleep time and the sleep time
The wireless LAN communication apparatus comprising: delete delete A sleep control method performed in a wireless local area network (WLAN)
Determining a sleep time using a traffic transmission amount and a traffic delay requirement of the wireless LAN communication device; And
Maintaining the consumed power of the wireless communication module of the wireless LAN communication device in the sleep state during the sleep time
Lt; / RTI >
Wherein the determining comprises:
Determining a minimum sleep time and a maximum sleep time according to the traffic transmission amount and the traffic delay requirement,
Determining a minimum value and a maximum value that can be a sleep time as the minimum sleep time and the maximum sleep time if the expected packet delay for the traffic transmission amount is equal to or less than the traffic delay requirement,
And determining a value corresponding to one half of a minimum value and a maximum value that can be taken as the sleep time as the minimum sleep time and the maximum sleep time when the expected packet delay for the traffic transmission amount exceeds the traffic delay requirement
The sleep control method comprising the steps of:

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