KR20150093128A - Method and device for recognition of information included in frame - Google Patents

Abstract

A step of performing synchronization through a synchronization period of a frame and a step of recognizing whether there is desired information in a remaining portion of the listening interval after the recognition block through a recognition block of a listening period included in the frame, A method and apparatus are provided for perceiving information.

Description

TECHNICAL FIELD The present invention relates to a method and apparatus for recognizing information included in a frame,

The present invention relates to a method and apparatus for recognizing information contained in a frame of a distributed network.

In an existing wireless local area network (WLAN) system, an access point (AP) can centrally provide the terminal with a beacon start timing and a contention-based time resource region. At this time, the terminal can receive service information (i.e., discovery information) from the AP after association with the AP. In addition, in the conventional WLAN system, the AP provides the beacon start timing information, and the terminal (in particular, the sleep mode terminal) receives the beacon only for a predetermined time period do. In this case, a power saving effect can be expected. However, since all terminals need to access the AP to know the search information, the system efficiency may deteriorate.

For example, even if the AP connected to the terminal A can not provide the terminal A with a service desired by the terminal A, the terminal A may access the AP. Or if the AP connected to the terminal B provides the terminal B with a service desired by the terminal B, the terminal A connected to the AP unnecessarily may adversely affect the terminal B and the system efficiency may deteriorate at this time.

Also, a method is required for each terminal to increase the system efficiency even in a distributed node system in which there is no AP, not a WLAN system in which an AP exists. At this time, the distributed node system includes a system in which each node communicates with another peer as a peer. That is, there is a need for a technology capable of increasing the system efficiency and power saving effect by allowing each terminal to acquire the start timing of a frame in the distributed node system and acquire search information before connecting to the system.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus capable of reducing power consumption of a peer device by recognizing information contained in a frame of a distributed network in advance.

According to one embodiment of the present invention, a method is provided in which a terminal recognizes information contained in a frame. The information recognizing method includes the steps of performing synchronization through a synchronization period of a frame and determining whether information is present in a remaining portion of the listening interval after a recognition block through a recognition block of a listening period included in the frame .

Recognizing in the information-aware manner may include receiving a physical layer signal transmitted in the recognition block, and determining whether there is information in the remaining portion through the received power of the physical layer signal.

The step of recognizing whether information is present in the remaining part through the received power of the physical layer signal in the information recognition method includes the steps of comparing the received power of the physical layer signal with a threshold value, Determining that no information is present in the remaining part, and determining that information exists in the remaining part if the received power is greater than the threshold value.

The information recognizing method may further include switching to a sleep mode for the remaining part when recognizing that there is no information in the remaining part through the recognition block.

The information recognition method may further include the step of, when recognizing that information is present in the remaining part through the recognition block, maintaining a listening mode for the remaining part.

In the information recognition method, the listening interval may be a search interval, the recognition block may be a search cognitive block, and the remaining portion may include at least one search execution block.

In the information recognition method, the search-aware block may include a plurality of sub-blocks capable of displaying the state of the terminal.

The method may further include receiving a physical layer signal in one subblock of the plurality of subblocks.

In the information recognition method, one of the at least one search execution block may include a PDDU including a search information and a search type, and a header of the PDDU.

In the information recognition method, the listening interval may be a peering interval, the recognition block may be a peering recognition block, and the rest may be a peering execution block.

According to another embodiment of the invention, there is provided a computer program product comprising at least one processor,

At least one processor executing at least one program stored in a memory to perform synchronization through a synchronization interval of a frame, and a step of performing synchronization through a recognition block of a listening period included in the frame And a step of recognizing whether there is information in the remaining part of the listening interval after the recognition block is provided.

At least one processor in the terminal performs a step of recognizing when receiving a physical layer signal transmitted in a recognition block and recognizing whether there is information in a remaining part through received power of a physical layer signal .

Wherein at least one processor in the terminal is configured to compare the received power of a physical layer signal with a threshold value when performing a step of determining whether information is present in a remaining part through a received power of a physical layer signal, Determining that information does not exist in the remaining part if the received power is smaller than the threshold value, and determining that information exists in the remaining part if the received power is greater than the threshold value.

The at least one processor in the terminal may further perform a step of switching to a sleep mode for the remaining part when recognizing that there is no information in the remaining part through the recognition block.

At least one processor in the terminal may further perform a step of maintaining a listening mode for the remaining part if it recognizes that there is information in the remaining part through the recognition block.

The listening interval in the terminal may be a search interval, the recognition block may be a search cognitive block, and the remaining portion may include at least one search execution block.

The search-aware block in the terminal may include a plurality of sub-blocks capable of displaying the state of the terminal.

The wireless communication unit in the terminal can receive the physical layer signal in one of the subblocks.

One of the at least one search execution block in the terminal may include a PDDU including a search information and a search type, and a header of the PDDU.

The listening interval in the terminal may be a peering interval, the acknowledgment block may be a peering acknowledgment block, and the remaining portion may be a peering execution block.

According to one embodiment of the present invention, the UE can selectively switch to the sleep mode even in the listening interval by recognizing whether desired information exists in the listening interval through the recognition block included in the listening interval. Therefore, if the desired information does not exist in the listening interval through the cognitive block, the terminal according to the embodiment of the present invention can reduce the power consumption by switching to the sleep mode even in the listening interval.

1 is a diagram illustrating a frame of a distributed node system according to an embodiment of the present invention.
2 is a diagram illustrating a synchronization interval according to an embodiment of the present invention.
3 is a diagram illustrating a search interval according to an embodiment of the present invention.
4 is a diagram illustrating a search interval according to another embodiment of the present invention.
5 is a diagram illustrating a protocol stack according to an embodiment of the present invention.
6 is a diagram illustrating a peering interval according to an embodiment of the present invention.
7 is a block diagram illustrating a wireless communication system according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, a peer device (PD) is referred to as a terminal, a mobile station (MS), a mobile terminal (MT), an advanced mobile station (AMS) a high reliability mobile station (HR-MS), a subscriber station (SS), a portable subscriber station (PSS), an access terminal (AT), a user equipment MT, MS, AMS, HR-MS, SS, PSS, AT, UE, and the like.

Also, a base station (BS) is an advanced base station (ABS), a high reliability base station (HR-BS), a node B, an evolved node B, eNodeB), an access point (AP), a radio access station (RAS), a base transceiver station (BTS), a mobile multihop relay (MMR) (RS), a relay node (RN) serving as a base station, an advanced relay station (ARS) serving as a base station, a high reliability relay station (HR) A femto BS, a home Node B, a HNB, a pico BS, a metro BS, a micro BS, ), Etc., and may be all or part of an ABS, a Node B, an eNodeB, an AP, a RAS, a BTS, an MMR-BS, an RS, an RN, an ARS, It may include a negative feature.

1 is a diagram illustrating a frame of a distributed node system according to an embodiment of the present invention.

Referring to FIG. 1, a frame of a distributed network according to an exemplary embodiment of the present invention is configured in units of one synchronization interval 100, and each synchronization interval 100 includes a synchronization period 110, A search interval 120, a peering interval 130, and a data communication interval 140.

The synchronization period 110 is a period in which a peer device (PD) synchronizes its own timing with the network synchronization. In the synchronization period, each PD can transmit a synchronization signal for providing a start timing of a frame.

In the search section 120, information about a service that can be provided by a PD or information about a request for a service to be provided by the PD (i.e., search information) may be transmitted. In this interval, the PD can determine whether to connect to another PD through the search information transmitted by the other PD. That is, the PDs included in the distributed network can perform discovery through the search interval 120 before association to the distributed network.

The peering period 130 is a period in which the PD establishes a link with another PD. At this time, the other PDs may be one or more, and one PD may be the PD that has decided to establish the connection through the search interval 120. [

The data communication section 140 is a section in which one PD transmits and receives data to and from at least one PD connected through the peering interval 130.

According to one embodiment of the present invention, each synchronization interval 100 includes a guard period between the synchronization period 110, the search period 120, the peering period 130, and the data communication period 140 . Each interval (synchronization interval, search interval, peering interval, etc.) included in the synchronization interval 100 in the embodiment of the present invention may include at least one slot or a sub slot. The guard interval may be included between each interval included in the synchronization interval 100 to ensure reliability of the PD synchronization in a distributed network in which there is no centralized time reference. The guard interval may comprise at least one orthogonal frequency division multiplexing (OFDM) symbol or a single carrier (SC) symbol.

According to an embodiment of the present invention, the synchronization interval 110 included in the synchronization interval 100 is located at the beginning of the synchronization interval 100, and the search interval 120, the peering interval 130, And the order of the data communication section 140 may be changed.

2 is a diagram illustrating a synchronization interval according to an embodiment of the present invention.

2, a synchronization interval 110 according to an embodiment of the present invention includes a portion where a synchronization reference signal (SRS) 112 is transmitted and at least one backoff slot 111 ). The length of the portion where the SRS is transmitted is included in the synchronization period 110. [ The number of backoff slots 111 may be changed dynamically according to the congestion of the network, and each backoff slot 111 may include a plurality of OFDM symbols. For example, when the length of the synchronization interval 110 is 512 usec and the length of the SRS is 16 usec, the number of backoff slots 111 in one synchronization period is 32, and the length of each backoff slot 111 is 16 usec , And the length of each OFDM or SC symbol may be 4 usec.

According to an embodiment of the present invention, a PD participating in a synchronization procedure transmits an SRS according to a random access method based on Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) . The SRS transmitted by the PD may include a timing offset indication field (TOIF) and a guard time. In one embodiment of the present invention, the SRS may be a signal having a correlation between synchronous signals (PD commonality), or a signal having a mutual inertia (PD orthogonality) between synchronous signals. At this time, the timing offset information includes timing offset information about a timing offset of the frame. For example, the timing offset information of the frame may be an index of a slot through which the SRS is transmitted. In one embodiment of the present invention, the timing offset information of a frame may be used to synchronize the last time of every synchronization interval. And the timing offset information may be conveyed through the orthogonality of the message or sequence transmitted in the physical layer. Through orthogonality of the sequence, the timing offset information can be mapped to a specific sequence having orthogonality. When the message is transmitted, the timing offset information is carried in a message, and the PD receiving the message can recognize the timing offset information by restoring the message through channel decoding.

The backoff slot 111 in which the SRS is not transmitted in the synchronization interval 110 may be referred to as a nulling interval. In this case, the nulling interval is for preventing collision between synchronization signals for each PD.

PDs included in a network according to an embodiment of the present invention may perform fully distributed synchronization through a synchronization interval 110. [ For example, when there is synchronization between a plurality of PDs, each PD can transmit the synchronization reference signal 112 independently of each other to maintain synchronization. Or one PD that is dynamically elected in one PD group may transmit the synchronous reference signal 112 when there is synchronization between the plurality of PDs.

According to an exemplary embodiment of the present invention, the initialized PD may search for a network synchronization in the synchronization interval 110, and may adjust its timing to network synchronization when it detects network synchronization maintaining synchronization mode). At this time, the PD according to an embodiment of the present invention can adjust the timing of the network synchronization through a pulse-coupled oscillator (PCO) synchronization algorithm. Alternatively, the PD may initiate an initial synchronization mode by transmitting an SRS if network synchronization is not present.

3 is a diagram illustrating a search interval according to an embodiment of the present invention.

Referring to FIG. 3, a search interval 120 according to an exemplary embodiment of the present invention includes a search discovery indication block 121 and a discovery execution block 122. In the search perception block 121, a serving terminal (PD) capable of providing a service or a served terminal (PD) desiring to receive a service may transmit a certain signal. The PD receiving the arbitrary signal can recognize that the search information is present in the search block 122 through the power level estimation of the received signal. At this time, the search information may be information on a service that can be provided, or request information of a service to be provided. The PD recognizing that there is search information in the search cognitive block 121 may then execute a substantial discovery procedure in the search cue block 122. [

Generally, the PD synchronized through the synchronization interval 110 receives a search signal in the search interval 120 to determine whether there is search information. If there is no search information to provide a desired service, the PD changes to a sleep mode for a subsequent interval. In this case, even when there is no search information, the PD must maintain a listening mode in the entire search interval 120, so that the power of the PD can be wasted.

However, in one embodiment of the present invention, each PD can reduce the power that may be unnecessarily consumed in the PD through the acknowledgment block. That is, in a synchronization interval according to an exemplary embodiment of the present invention, a period (hereinafter referred to as a 'listening period') in which a PD must be operated in a listening mode, such as a search interval 120, block, and each PD can know whether there is information in a subsequent execution block of the listening interval through the recognition block. If the PD determines that there is no information in the execution block after the listening interval through the acknowledge block, the PD can switch to the sleep mode for the rest of the execution blocks after the listening interval. In one embodiment of the present invention, the search interval 120 and the peering interval 130 are defined as the listening interval.

In one embodiment of the present invention, the signal transmitted by the PD in the search-aware block 121 may be any physical layer signal. The PD receiving the signal in the search cue block 121 may estimate the energy of the received signal and recognize that there is information in the search execution block 122 thereafter.

For example, the energy of the received signal may be estimated through the average power level during the search cue block 121, and the PD performing the energy estimation may compare the magnitude of the estimated power with a predetermined threshold value If the magnitude of the estimated power is smaller than the threshold value, it is determined that the information does not exist in the search execution block 122, and the search execution block 122 switches to the sleep mode. That is, the PD requesting the service decides that the PD providing the service is not around, and does not transmit the search message including the service request in the search execution block 122 thereafter. Or the PD that can provide the service does not have the PD requesting the service nearby and does not transmit the search message including the information about the service that can be provided in the search execution block 122 thereafter.

However, if the magnitude of the estimated power is greater than or equal to the threshold, the PD may determine that information is present in the search execution block 122 and then wait for information in the search execution block 122. Then, the PD can restore the information transmitted from the search execution block 122 and confirm that the restored information is search information related to the service requested by the PD. Alternatively, the PD may restore the information transmitted in the search execution block 122 to check whether there is search information for requesting a service.

4 is a diagram illustrating a search interval according to another embodiment of the present invention.

4, a search interval 120 according to another embodiment of the present invention includes a search cognitive block 121 and a search execution block 122, and the search cognitive block 121 includes a plurality of sub- 121 ₁ , 121 ₂ , ..., 121 _n . In another embodiment of the present invention, a plurality of subblocks 121 ₁ , 121 ₂ , ..., 121 _n included in the search-aware block 121 may indicate the state of the PD (state indication sub-block) . In another embodiment of the present invention, a PD may transmit a physical layer signal by selecting one subblock among a plurality of subblocks 121 ₁ , 121 ₂ , ..., 121 _n . In this case, the physical layer signal transmitted by the PD is also a signal indicating that the search information is present in the following search execution block 122 as in the case of FIG.

5 is a diagram illustrating a protocol stack according to an embodiment of the present invention.

Referring to FIG. 5, in an application layer or middleware, search information is generated and mapped to a MAC discovery data unit (MDDU) payload of a media access control (MAC) layer. At this time, the search type of the search information is mapped to the MDDU header of the MAC layer. The search type may include advertisement, publish and subscribe, and query and reply information. In the MAC layer, a frame check sequence (FCS) bit is added after the MDDU payload.

Thereafter, the MDDU header, the MDDU payload, and the FCS of the MAC layer may be mapped to a physical discovery data unit (PDDU) payload in the physical (PHY) layer. After the PDDU header is added to the PDDU payload in the PHY layer, the PDDU header and the PDDU payload are mapped to one of the plurality of search execution blocks 122 included in the search interval 120 .

6 is a diagram illustrating a peering interval according to an embodiment of the present invention.

Referring to FIG. 6, the peering interval 130 includes a peering indication block 131 and a peering execution block 132 at the beginning of the peering execution block 120 as in the search interval 120, It is the listening interval during which the PD wakes up and receives a signal. At this time, the role of the peering recognition block 131 is also the same as that of the search recognition block 121. That is, a PD that is to perform peering in the peering execution block 132 may transmit an arbitrary physical layer signal through the peering acknowledgment block 131, and a PD that receives an arbitrary physical layer signal in the peering acknowledgment block 131 The peering execution block 132 may know that there is a PD to perform peering. If the PD does not receive any physical layer signal in the peering or block 131, the PD may then transition to the sleep mode in the peering execution block 132. [

As described above, according to the embodiment of the present invention, the PD can selectively switch to the sleep mode in the execution block of the listening interval by recognizing whether there is desired information in the listening interval through the recognition block included in the listening interval. Therefore, if the desired information does not exist in the listening interval through the recognition block, the PD according to the embodiment of the present invention can reduce the power consumption by switching to the sleep mode even in the execution block of the listening interval.

7 is a block diagram illustrating a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 7, a wireless communication system 700 according to an embodiment of the present invention includes a terminal 1 710 and a terminal 2 720 located near the terminal 1.

The terminal 1 710 and the terminal 2 720 include processors 711 and 721, memories 712 and 722 and radio frequency units (RF units) 713 and 723 do. The memories 712 and 722 may be connected to the processors 711 and 721 to store various information for driving the processors 711 and 721. The wireless communication units 713 and 733 are connected to the processors 711 and 721 to transmit and receive wireless signals. The processors 711 and 721 may implement the functions, processes, or methods proposed in the embodiments of the present invention. In this case, in the wireless communication system according to an embodiment of the present invention, the wireless interface protocol layer can be implemented by the processors 711 and 721. [ The operations of the terminal 1 710 and the terminal 2 720 according to the embodiment of the present invention can be implemented by the processors 711 and 721.

In an embodiment of the present invention, the memory may be located inside or outside the processor, and the memory may be connected to the processor via various means already known. The memory may be any type of volatile or nonvolatile storage medium, e.g., the memory may include read-only memory (ROM) or random access memory (RAM). 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, It belongs to the scope of right.

Claims (20)

A method for a terminal to recognize information contained in a frame,
Performing synchronization through a synchronization interval of the frame, and
Determining whether there is information in the rest of the listening interval after the recognition block through a recognition block of a listening period included in the frame;
/ RTI > The method of claim 1,
Wherein the recognizing comprises:
Receiving a physical layer signal transmitted in the perceptual block, and
Determining whether the information is present in the remaining part through the received power of the physical layer signal
/ RTI > 3. The method of claim 2,
Wherein the step of determining whether the information is present in the remaining part through the received power of the physical layer signal comprises:
Comparing the received power of the physical layer signal with a threshold value,
Determining that the information does not exist in the remaining part if the received power is smaller than the threshold value, and
Determining that the information is present in the remaining part if the received power is greater than the threshold;
/ RTI > The method of claim 1,
Further comprising switching to a sleep mode during the remaining part if it is recognized that the information is not present in the remaining part through the recognition block. The method of claim 1,
If it is recognized through the recognition block that the information is present in the remaining part, maintaining a listening mode for the remaining part
≪ / RTI > 3. The method of claim 2,
Wherein the listening interval is a search interval, the cognitive block is a search cognitive block, and the remaining portion comprises at least one search execution block. The method of claim 6,
Wherein the search cognition block comprises a plurality of subblocks capable of indicating a state of the terminal. 8. The method of claim 7,
Receiving the physical layer signal in one sub-block of the plurality of sub-blocks
≪ / RTI > The method of claim 6,
Wherein the one search execution block of the at least one search execution block includes a physical discovery data unit (PDDU) including search information and a search type, and a header of the PDDU. 3. The method of claim 2,
Wherein the listening interval is a peering interval, the recognition block is a peering acknowledgment block, and the remaining portion is a peering execution block. At least one processor,
Memory, and
Wireless communication section
Lt; / RTI >
The at least one processor executing at least one program stored in the memory,
Performing synchronization through a synchronization interval of the frame, and
Determining whether there is information in the rest of the listening interval after the recognition block through a recognition block of a listening period included in the frame;
. 12. The method of claim 11,
Wherein the at least one processor, when performing the perceiving step,
Receiving a physical layer signal transmitted in the perceptual block, and
Determining whether the information is present in the remaining part through the received power of the physical layer signal
. The method of claim 12,
Wherein the at least one processor, when performing the step of determining whether the information is present in the remaining part through the received power of the physical layer signal,
Comparing the received power of the physical layer signal with a threshold value,
Determining that the information does not exist in the remaining part if the received power is smaller than the threshold value, and
Determining that the information is present in the remaining part if the received power is greater than the threshold;
. 12. The method of claim 11,
Wherein the at least one processor comprises:
Further comprising the step of switching to a sleep mode during the remaining part if it is recognized that the information is not present in the remaining part through the cognitive block. 12. The method of claim 11,
Wherein the at least one processor comprises:
Further comprising the step of maintaining a listening mode for the remaining part if the information is recognized in the remaining part through the recognition block. The method of claim 12,
Wherein the listening interval is a search interval, the cognitive block is a search cognitive block, and the remaining portion comprises at least one search execution block. 17. The method of claim 16,
Wherein the search cue block comprises a plurality of sub-blocks capable of indicating the state of the terminal. The method of claim 17,
Wherein the wireless communication unit receives the physical layer signal in one subblock among the plurality of subblocks. 17. The method of claim 16,
Wherein one of the at least one search execution block includes a physical discovery data unit (PDDU) including search information and a search type, and a header of the PDDU. The method of claim 12,
Wherein the listening interval is a peering interval, the awareness block is a peering acknowledgment block, and the remaining portion is a peering execution block.

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