KR101706343B1 - Method and relay for switching between downlink and uplink - Google Patents

Abstract

A method of switching between uplink and downlink according to time elapses includes the steps of receiving a signal of a base station, determining whether a reference signal exists in a frame of the signal, Determining an uplink downlink configuration corresponding to the user terminal, and switching the uplink and downlink over time based on the determined uplink downlink configuration.

Description

[0001] METHOD AND RELAY FOR SWITCHING BETWEEN DOWNLINK AND UPLINK [0002]

The present invention relates to a method and a repeater for switching uplink and downlink.

In a time division wireless communication system, for example, in a 3GPP LTE / LTE-A TDD system, a downlink or an uplink is switched between a base station and a user terminal over time, and transmission and reception switching for uplink and downlink switching In order to generate a signal, it is necessary to know what type of time division frame structure is most important. In this case, in case of 3GPP LTE / LTE-A TDD system, there are seven different types of time-division frame structures, and there are 18 (related to general periodic prefixes and 10 Considering the different types of special subframes (SSFs) of the eight sums associated with periodic prefix calls, a total of 126 different time-division frame structures may exist.

Since the user terminal needs to know which time-division frame structure currently used by the base station is capable of communication, when the base station broadcasts a system information block (SIB) throughout the cell, the base station receives and decodes the system information block, It is possible to find out the time-division frame structure used in the present invention. In this regard, a configuration disclosed in Japanese Patent Laid-Open Publication No. 10-2013-0046607 published on Nov. 6, 2013 is such that a user terminal receives and decodes a system information block transmitted from a base station.

On the other hand, in the case of communication using a repeater, the repeater also needs to know the time division frame structure used by the base station. However, if the repeater is provided with all the functions and resources necessary for decoding the system information block, such as a user terminal, the system complexity of the repeater is increased and the price competitiveness of the repeater may also be lowered.

The present invention has been made to solve the problems of the background art described above, and it is an object of the present invention to provide a method and apparatus for receiving a time division frame structure information from a base station without separately receiving the information, And to provide a repeater that can recognize the time division frame structure being used.

It is also possible to find out one or more of the uplink downlink configuration and the special subframe configuration using a synchronization signal that can be easily grasped from the signal and to switch the uplink and downlink based thereon And provide a repeater.

It is also intended to provide a method and a repeater capable of inferring the type of a time division frame structure by specifying a subframe or symbol for an uplink in a signal and a method for distinguishing a subframe or symbol for a downlink .

It is to be understood, however, that the technical scope of the present invention is not limited to the above-described technical problems, and other technical problems may exist.

As a technical means for accomplishing the above technical object, an embodiment of the present invention is implemented by a repeater, comprising: receiving a signal of a base station; determining whether a reference signal exists in a frame of the signal; Determining an uplink downlink configuration corresponding to the base station and a user terminal according to the determination result, and determining an uplink downlink configuration for switching uplink and downlink over time based on the determined uplink downlink configuration And a method for switching between an uplink and a downlink that includes a step.

According to one embodiment of the present invention, a method of switching between uplink and downlink further comprises, after said receiving, detecting at least one synchronization signal from said signal, Wherein each of the frames is distinguished from each other based on the synchronization signal, and the determining step determines whether the reference signal exists based on the synchronization signal.

According to an embodiment of the present invention, the synchronization signal may include a primary synchronization signal (PSS) and a secondary synchronization signal (SSS).

According to one embodiment of the present invention, a method of switching between uplink and downlink further comprises determining a configuration of a special sub-frame of the frame after the step of determining the uplink downlink configuration, May switch the uplink and downlink over time based on the determined uplink downlink configuration and the configuration of the special subframe.

According to one embodiment of the present invention, a method for switching between uplink and downlink comprises determining, after determining the uplink downlink configuration, that at least one of a plurality of symbols of a special subframe among a plurality of subframes of the frame Further comprising determining whether a reference signal exists in the symbol, wherein the step of determining the configuration of the special subframe comprises determining whether a reference signal exists in the at least one symbol, And the configuration of the special sub-frame is determined according to the determination result

According to an embodiment of the present invention, there is provided a method of switching between uplink and downlink, comprising the steps of: determining whether a reference signal is present in the at least one symbol; determining whether a cyclic prefix Determining the type of the special subframe, wherein the step of determining the configuration of the special subframe determines the configuration of the special subframe based on the determined type of the periodic prefix call.

According to another embodiment of the present invention, there is provided a base station comprising: a receiver for receiving a signal of a base station; a reference signal determiner for determining whether a reference signal exists in the frame of the signal; An uplink downlink configuration determiner for determining an uplink downlink configuration and a repeater for switching an uplink and a downlink over time based on the determined uplink downlink configuration, have.

According to another embodiment of the present invention, the reference signal determination unit determines whether a reference signal exists in at least one subframe among a plurality of subframes of the frame, and the repeater determines from the signal at least one synchronization signal And a synchronization signal detector for detecting a synchronization signal, wherein each of the plurality of subframes is distinguished from each other based on the synchronization signal.

According to another embodiment of the present application, the repeater further comprises a special sub-frame configuration determiner for determining the configuration of a special sub-frame of the frame, wherein the switching unit is based on the determined uplink downlink configuration and the configuration of the special sub- And switches the uplink and the downlink according to the elapse of time.

According to another embodiment of the present invention, there is provided a method of transmitting a signal in a time division frame structure, the method comprising: receiving a signal of a base station; determining whether a reference signal exists in the frame of the signal; Determining a type of the plurality of types corresponding to the base station and the user terminal, and switching the uplink and the downlink over time based on the determined one type of the time-division frame structure And can provide a method of switching the uplink and downlink depending on the type.

According to the above-mentioned problem solving means of the present invention, the repeater can separately receive information for knowing the time division frame structure from the base station or grasp the time division frame structure used by the base station by using the signal own characteristic without decoding the received information. Thereby making it possible to provide an uplink downlink switching method and a repeater which enable lower complexity and lower cost production.

It is also possible to find out one or more of the uplink downlink configuration and the special subframe configuration using a synchronization signal that can be easily grasped from the signal and to switch the uplink and downlink based thereon You can provide a way and a repeater.

By specifying a method of using a reference signal to distinguish a subframe or symbol for an uplink in a signal and a subframe or a symbol for a downlink, a method of inferring the type of the time division frame structure and a repeater .

1 is a diagram schematically illustrating a communication system according to an embodiment of the present invention.
2 is a view for explaining an example of a downlink and an uplink between a base station, a relay, and a user terminal.
3 is a configuration diagram of a repeater according to an embodiment of the present invention.
4 is a configuration diagram of a repeater according to an embodiment of the present invention.
5A to 5D are views for explaining an example of the structure of a frame.
6 is a diagram for explaining an example of a different type or uplink downlink configuration of a time division frame structure.
Figs. 7A, 7B, 8A and 8B are diagrams for explaining an example of the configuration of different types or special sub-frames of a special sub-frame.
9 is a flowchart illustrating an example of a process in which uplink downlink switching is performed.
10 is an operational flow diagram illustrating an uplink downlink switching method in accordance with one embodiment of the present application.

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. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is " on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise.

The terms "about "," substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure. The word " step (or step) "or" step "used to the extent that it is used throughout the specification does not mean" step for.

1 is a diagram schematically illustrating a communication system according to an embodiment of the present invention. 1, the communication system 1 includes a base station 10, a repeater 20, a user terminal 30, and a user terminal 40. As shown in Fig. It should be understood, however, that FIG. 1 illustrates only one embodiment of the present application, and FIG. 1 may be configured differently according to various embodiments of the present disclosure. As an example, the communication system 1 may further include a control server (not shown) for remotely controlling the operation of the base station 10 or the repeater 20.

One example of the communication system 1 is a 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE), and the 3GPP LTE system is part of an Evolved-Universal Mobile Telecommunications System (E-UTMS) And SC-FDMA can be employed. The LTE-A (LTE-Advanced) system is an evolution of LTE systems and can have backward compatibility with LTE systems. In addition, the LTE system may be a system based on 3GPP TS Release 8. Further, each of the LTE system and the LTE-A system may mean an LTE (Time Division Duplex) system and an LTE-A TDD system. Hereinafter, for the sake of clarity, the 3GPP LTE / LTE-A TDD system is mainly described, but the technical idea of the present invention is not limited thereto. For example, the communication system 1 according to the present invention can be applied to various communication systems such as International Mobile Telecommunication (IMT) -2000, Code Division Multiple Access (CDMA) -2000, W-Code Division Multiple Access (W-CDMA), Wireless Broadband Internet It may be the same.

Referring to FIG. 1, a communication system 1 includes at least one base station 10. Each base station 10 provides communication services for a particular geographical area 11, commonly referred to as a cell. The base station 10 generally refers to a fixed point in communication with the user terminal 30 or the user terminal 40 and includes an evolved Node B (eNB), a Base Transceiver System (BTS), an Access Point (AN) Access Network) and the like. The base station 10 may perform functions such as connectivity, management, control and resource allocation with the user terminal 30 or the user terminal 40.

The user terminal 30 or the user terminal 40 may be fixed or mobile and may be a mobile station, a user terminal (UT), a subscriber station (SS), a wireless device, a wireless modem ), A portable device (Handheld Device), an AT (Access Terminal), and the like.

Also, according to various embodiments of the present disclosure, the user terminal 30 or the user terminal 40 may be various types of terminals. For example, the terminal may be a TV device, a computer, or a portable terminal capable of connecting to a remote server via a network. Here, an example of the TV apparatus includes a smart TV, an IPTV set-top box, and the like. Examples of the computer include a notebook computer, a desktop computer, a laptop computer, One example of the terminal includes a Personal Communication System (PCS), a Global System for Mobile Communications (GSM), a Personal Digital Cellular (PDC), a Personal Handyphone System (PHS) Assistant, IMT (International Mobile Telecommunication) -2000, Code Division Multiple Access (CDMA) -2000, W-Code Division Multiple Access (W-CDMA), Wibro (Wireless Broadband Internet) terminals, smart phones, And the like may be included in the present invention. Hereinafter, for convenience of description, it is assumed that the user terminal 30 or the user terminal 40 is an LTE terminal supporting LTE or an LTE-A terminal supporting both LTE and LTE-A.

A relay 20 is a device that relays a signal between the base station 10 and the user terminal 30 and may be referred to as another term such as an RN (Relay Node), a repeater, or an RS.

Each of the user equipment (UE) 30 or the user equipment 40 can be classified according to whether the user equipment 30 is a terminal directly communicating with the base station 10 or a terminal communicating through the repeater 20. Referring to FIG. 1, a user terminal 30 may refer to a terminal that communicates with a repeater 20 and may be referred to as a relay UE. On the other hand, the user terminal 40 is a terminal directly communicating with the base station 10 and may be called a macro terminal (macro UE).

Hereinafter, downlink (DL) refers to communication from the base station 10 to the user terminal 30 or the user terminal 40, and uplink (UL) refers to communication from the user terminal 30 or the user terminal 40 ) To the base station 10, as shown in FIG.

2 is a view for explaining an example of a downlink and an uplink between a base station, a relay, and a user terminal. 2, when a repeater 20 is located between a base station 10 and a user terminal 30, a downlink is a communication path from a base station 10 to a user terminal 30 via a repeater 20 And the uplink may mean communication from the user terminal 30 to the base station 10 via the repeater 20.

The backhaul link refers to the link between the base station 10 and the repeater 20 and the backhaul downlink refers to communication from the base station 10 to the repeater 20 and the backhaul uplink refers to the link between the repeater 20 ) To the base station 10 as shown in FIG. In addition, an access link means a link between the repeater 20 and the user terminal 30, an access downlink means a communication from the repeater 20 to the user terminal 30, (30) to the repeater (20).

The repeater 20 determines an uplink downlink configuration corresponding to the base station 10 and the user terminal 30 based on the signal received from the base station 10, Link and downlink can be switched. In other words, the repeater 20 determines a type corresponding to the base station 10 and the user terminal 30 among the plurality of types of the time-division frame structure through the signal received from the base station 10, The uplink and downlink may be switched based on one type.

The repeater 20 can determine whether or not a reference signal exists in a frame within the signal and determine the uplink downlink configuration according to the determination result. At this time, the repeater 20 can determine whether a reference signal exists in at least one subframe among a plurality of subframes in the frame. At this time, the plurality of subframes include subframes 0 to 9, and at least one subframe may include subframe 3, subframe 4, subframe 7, and subframe 9. In addition, the repeater 20 can determine whether or not a reference signal exists in at least one subframe according to whether or not the reference signal power is detected in at least one subframe.

The repeater 20 detects at least one synchronization signal from the signal received from the base station 10 and can determine whether or not a reference signal exists based on the detected synchronization signal. At this time, the synchronization signal includes a primary synchronization signal (PSS) and a secondary synchronization signal (SSS).

The repeater 20 may determine the configuration of a Special Subframe (SSF) in addition to determining the uplink downlink configuration (or determining the type of time division frame structure). At this time, the repeater 20 can switch the uplink and downlink over time based on the configuration of the uplink downlink configuration (or the type of the time division frame structure) and the special subframe.

In determining the configuration of the special sub-frame, the repeater 20 determines whether or not a reference signal exists in at least one symbol among the plurality of symbols of the special sub-frame among the plurality of sub-frames of the frame, The configuration of the subframe can be determined. At this time, the plurality of symbols include symbols 0 to 13, and at least one symbol may include symbol 0, symbol 4, symbol 7, and symbol 11.

The repeater 20 may determine the type of the cyclic prefix (CP) of the plurality of symbols and determine the configuration of the special subframe based on the type of the determined cyclic prefix call. At this time, the type of the cyclic prefix call includes, but is not limited to, an extended cyclic prefix call type and a normal cyclic prefix call type.

Thus, the repeater 20 can transmit the system information or the control information, which the base station 10 has decided to communicate with the user terminal 30, transparently without decoding the system information or the control information received from the base station 10. [ It is possible to grasp the uplink downlink configuration (or the type of the time division frame structure) and the special subframe configuration, thereby relaying the communication between the base station 10 and the user terminal 30. [

Hereinafter, each of the configurations of Figs. 1 and 2 described above will be described in more detail.

3 is a configuration diagram of a repeater according to an embodiment of the present invention. Referring to FIG. 3, the repeater 20 may include a communication unit 210, a reference signal determination unit 230, an uplink downlink configuration determination unit 250, and a switching unit 270. 3 shows only one embodiment of the present invention. According to various embodiments of the present invention, the configuration of the repeater 20 may be configured differently from that of FIG.

The communication unit 210 can receive the signal of the base station 10. At this time, the signal of the base station 10 may be a signal generated by the base station 10 and transmitted from the base station 10. Also, such a signal may be transmitted to all devices in the cell area of the base station 10.

The reference signal determination unit 230 can determine whether a reference signal exists in a frame of the base station 10 signal. At this time, the reference signal determination unit 230 may determine whether a reference signal exists in at least one subframe among a plurality of subframes of the frame. If the reference signal power is detected in at least one subframe , It can be determined that the reference signal exists in at least one subframe.

The uplink downlink configuration determiner 250 determines whether the uplink downlink configuration (or the time division basis) corresponding to the base station and the user terminal according to the determination result of the existence of the reference signal in the frame or subframe of the base station 10 signal The type of frame structure).

The switching unit 270 may switch the uplink and downlink over time based on the determined uplink downlink configuration (or type of time division frame structure). At this time, the switching unit 270 generates a transmission / reception switching signal based on the determined uplink downlink configuration (or type of the time division frame structure), and based on the generated transmission / reception switching signal, Lt; / RTI > In addition, the transmission / reception switching signal is a signal for controlling a module necessary for switching the uplink and the downlink among the modules inside or outside the base station 20, and an example of a module required for switching the uplink and downlink is The communication unit 210, the transmitting unit 241 of FIG. 4, the receiving unit 242 of FIG. 4, and the memory 280 of FIG.

4 is a configuration diagram of a repeater according to an embodiment of the present invention. 4, the repeater 20 includes a communication unit 210, a synchronization signal detection unit 220, a reference signal determination unit 230, an uplink downlink configuration determination unit 250, a special subframe configuration determination unit 260 ), A switching unit 270, and a memory 280. FIG. 4 also shows an embodiment of the present invention as shown in FIG. 3. Also, according to various embodiments of the present invention, the configuration of the repeater 20 may be configured differently from FIG. In FIG. 4, descriptions omitted from the description of the communication unit 210, the reference signal determination unit 230, the uplink downlink configuration determination unit 250, and the switching unit 270 are the same as those of FIG. Replace it with a description.

The communication unit 210 can receive the signal of the base station. At this time, the signal of the base station may include at least one frame or a radio frame. 4, the communication unit 210 may include a receiving unit 211 and a transmitting unit 212. The receiving unit 211 receives data, signals or information from the base station 10 or the user terminal 30 and the transmitting unit 212 can transmit data, signals or information to the base station 10 or the user terminal 30 have. The operations of the receiving unit 211 and the transmitting unit 212 may be performed under the control of the switching unit 270. [

5A to 5D are views for explaining an example of the structure of a frame. The structure of the frame (or radio frame) in FIGS. 5A to 5D may refer to a time division duplex (TDD) frame of the 3GPP LTE / LTE-A system, but is not limited thereto.

Referring to FIG. 5A, a frame (or radio frame) is composed of 10 subframes which are subframe 0 to subframe 9, and one subframe is composed of two slots. In addition, a frame (or radio frame) may be composed of two half-frames, and a half-frame may be composed of five sub-frames. 5A, the length of one frame (or radio frame) is 10 ms, the length of a half frame is 5 ms, the length of one subframe is 1 ms, and the length of one slot is 0.5 ms . Referring to FIG. 5A, the length of one frame (or radio frame) is 307200Ts, the length of a half frame is 153600Ts, the length of one subframe is 30720Ts, and one slot Lt; RTI ID = 0.0 > 1560Ts < / RTI >

Referring to FIG. 5B, one subframe and a slot may include a plurality of symbols. Referring to FIG. 5C, a slot may be composed of 7 symbols in a normal cyclic prefix (CP), and 6 OFDM symbols in an extended cyclic prefix (CP) . In this case, the symbol may be an orthogonal frequency division multiplexing (OFDM) symbol. As shown in FIG. 5B, a subframe with a regular periodic prefix call may include 14 OFDM symbols, symbol 0 through symbol 14. On the other hand, a subframe with an extended cyclic prefix call may include 12 OFDM symbols, symbol 0 through symbol 12.

The subframe may be any one of a subframe for uplink, a subframe for downlink, and a special subframe (SSF) according to its type. The subframe for the uplink is used only for the uplink data transmission and the subframe for the downlink can be used only for the downlink data transmission.

5D shows an example of a special sub-frame. Referring to FIG. 5D, the special subframe may include a Downlink Pilot Time Slot (DwPTS), a Guard Period (GP), and an Uplink Pliot Time Slot (UpPTS). At this time, the DwPTS is used for the downlink, the UpPTS is used for the uplink, and the GP can be used as the guard interval for eliminating the interference between the uplink and the downlink. For example, the DwPTS may be used for initial cell search, synchronization, or channel estimation, and the UpPTS may be used to align the channel estimation at the base station 10 with the uplink transmission synchronization of the UE, and GP may be used between the uplink and the downlink And can be used as a guard interval for eliminating the interference caused in the uplink due to the multipath delay of the downlink signal.

6 is a diagram for explaining an example of a different type or uplink downlink configuration of a time division frame structure. Referring to FIG. 6, the communication system 1, for example, the time division communication system 1, supports seven uplink downlink configurations (or seven types of time division frame structures). Here, D represents a downlink subframe, U represents an uplink subframe, and S may represent a special subframe including fields corresponding to DwPTS, GP, and UpPTS as described above.

Referring to FIG. 6, subframe 0, subframe 5 must be used for downlink transmission, subframe 2 must be used for uplink transmission, and subframe 1 must be a special subframe. On the other hand, subframes 3, 4, 7, 8, and 9 may be downlink subframes in some uplink downlink configurations, or uplink subframes in other uplink downlink configurations. In addition, subframe 6 may be special subframes in some uplink downlink configurations, or downlink subframes in other uplink downlink configurations.

The user terminal 30 is a system information block that is generated by the base station 10 via a predetermined module (e.g., a modem module) included therein or externally and includes information on the uplink downlink configuration Block can identify the uplink downlink configuration. However, in the case of the repeater 20, if the module (for example, a modem module) is not mounted, it is necessary to perform a separate operation for knowing the uplink downlink configuration (or the type of the time division frame structure). Hereinafter, the repeater 20 acquires the uplink downlink configuration (or the type of the time division frame structure) only by the signal of the base station 20 without receiving and decoding a separate system information block will be described in detail.

The synchronization signal detection unit 220 can detect at least one synchronization signal from the signal of the base station 10. [ At this time, the synchronization signal may include a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). 4, the synchronization signal detector 220 may include a PSS detector 221 and an SSS detector 222. [ Hereinafter, for the convenience of description, it will be described that the synchronization signal is detected by the synchronization signal detection unit 220. According to one embodiment of the present invention, the PSS is detected by the PSS detection unit 221, and the SSS is detected by the SSS detection unit 222, < / RTI >

The synchronization signal detection unit 220 can detect a main synchronization signal from the signal of the base station 10. A downlink signal (e.g., a downlink 3GPP LTE / LTE-A signal) transmitted by the base station 10 always includes a PSS signal within a central bandwidth (e.g., a center 1.4 MHz bandwidth) . The synchronization signal detector 220 can obtain time synchronization with the base station 10 in units of 5 ms through the PSS signal (or through correlation of the PSS signalization).

Referring to FIG. 5B, in a time division duplex (TDD) communication system, a PSS may be included in a third symbol of slot 2 of subframe 1 and a third symbol of slot 12 of subframe 6. That is, the PSS is transmitted in units of 5 ms, through which the synchronization signal detector 220 can obtain time synchronization with the base station 10 in units of 5 ms. In addition, the synchronization signal detector 220 can distinguish a plurality of subframes or a plurality of slots based on a point of time when the PSS is detected. 6, subframe 1 is always a special subframe and PSS can be transmitted as part of the DwPTS of subframe 1 while subframe 6 is a special subframe according to the uplink downlink configuration And it can be confirmed that the PSS is transmitted as part of the subframe 6 or as part of the DwPTS of the subframe 6. In this regard, as shown in FIG. 6, subframe 6 is a special subframe in uplink downlink configurations 0, 1, 2, and 6, and subframe 6 in uplink downlink configurations 3 through 5 is downlink subframes Frame.

The primary synchronization signal may be used for synchronization of at least one of the subframe, slot and symbol in the time domain. Also, since the main synchronization signal is located at the center of the channel bandwidth of the frequency domain, it may be used to identify the center of the channel bandwidth of the frequency domain. In addition, the main synchronization signal may include PSI (Physical layer cell identities), which are three cell IDs that exist for every 168 cell group IDs.

The synchronization signal detection unit 220 can detect the secondary synchronization signal from the signal of the base station 10. The synchronization signal detector 220 can accurately synchronize with the base station 10 in units of 10 ms through the secondary synchronization signal and can further determine the final cell ID of the base station 10. In general, the secondary synchronization signal can be used for synchronization of a frame (or radio frame), and includes 168 cell group identities, so that a precise frame (or radio frame) synchronization of 10 ms units can be achieved through the secondary synchronization signal When the main synchronization signal and the secondary synchronization signal are used, any one of 504 final cell IDs, which is a combination of 168 cell IDs and 3 cell IDs, can be determined. When the final cell ID is determined, the base station 10 transmits a reference signal (RS) used for downlink communication and a resource position of the reference signal (e.g., a symbol position including a reference signal) Can be determined.

Referring to FIG. 5B, in a time division duplex (TDD) communication system, the SSS may be included in the last symbol of slot 1 of subframe 0 and the last symbol of slot 11 of subframe 5. At this time, both of subframes 0 and 5 may be subframes for downlink.

The reference signal determination unit 230 can determine whether a reference signal exists in the frame of the base station 10 or not. Specifically, the reference signal determining unit 230 can determine whether a reference signal exists in at least one subframe among a plurality of subframes of the frame. Referring to FIG. 6, when the reference signal determination unit 230 determines that the reference signal is a reference to at least one of subframes 0 to 9, which is a plurality of subframes, subframe 3, subframe 4, subframe 7, It is possible to finally determine the uplink downlink configuration (or the type of the time division frame structure) used by the base station 10. Normal . In the TDD frame structure used in 3GPP LTE / LTE-A, since the reference signal is transmitted only in the subframe in which the downlink signal is transmitted, the presence or absence of the reference signal for the corresponding subframe in 10 subframe positions within 10 ms It is possible to grasp the TDD frame structure used by the base station 10 without decoding a separate system information block.

The reference signal determining unit 230 may determine whether a reference signal exists in at least one subframe according to whether the reference signal power is detected in at least one subframe. At this time, time synchronization with the base station 10 can be obtained in units of 5 ms through the main synchronization signal, as described above. Therefore, a frame or a specific subframe (for example, subframe 0, 1 or 6) The starting point may be determined based on the synchronization signal, and each of the plurality of subframes may be distinguished from each other based on the synchronization signal. That is, each of the plurality of subframes may be separated from each other according to a predetermined time interval from the start time.

As described above, precise frame synchronization with the base station 10 is possible in units of 10 ms through the secondary synchronization signal, and the final cell ID can be determined. Therefore, the base station 10 actually uses the reference The position of the signal and the reference signal can be determined and the reference signal determination unit 230 can extract the reference signal from the signal transmitted from the base station 10, specifically, the reference signal in the subframe of the signal.

The uplink downlink configuration determining unit 250 determines an uplink downlink configuration (or a type of a time division frame structure) corresponding to the base station 10 and the user terminal 30 according to a determination result of the reference signal determination unit 230 You can decide. At this time, the uplink downlink configuration determining unit 250 determines whether or not the uplink downlink configuration determination unit 250 determines the uplink downlink configuration based on the subframe 3, the subframe 4, the subframe 7, and the subframe 9, which are at least one subframe among the subframe 0 to subframe 9, Depending on whether a signal is present, it is possible to finally determine the uplink downlink configuration (or type of time division frame structure) used by the base station 10.

6, the uplink downlink configuration determining unit 250 determines that the uplink downlink configuration determination unit 250 determines that the uplink downlink configuration is the uplink downlink configuration, The link downlink configuration (or type of time division frame structure) may be determined as an uplink downlink configuration (or type of time division frame structure) 5 in uplink downlink configuration 0 to uplink downlink configuration 6. Alternatively, the uplink downlink configuration determiner 250 may determine that the reference signal exists only in the subframe 3, subframe 4, and subframe 9 of the signal of the base station 10, The type of structure) may be determined as an uplink downlink configuration (or type of time division frame structure) 2 uplink downlink configuration 0 to uplink downlink configuration 6.

The special sub-frame configuration determiner 260 can determine the configuration of a special sub-frame of a signal or a frame (or a radio frame). At this time, the special sub-frame configuration determiner 260 determines whether there is a reference signal in at least one symbol among the plurality of symbols of the special sub-frame among the plurality of sub-frames of the frame (or radio frame) The configuration of the special subframe can be determined according to the determination result of whether or not the reference signal exists in the symbol of the special subframe. At this time, the plurality of symbols include symbols 0 to 13, and at least one symbol may include symbol 0, symbol 4, symbol 7, and symbol 11.

Figs. 7A, 7B, 8A and 8B are diagrams for explaining an example of the configuration of different types or special sub-frames of a special sub-frame. Referring to FIGS. 7A and 7B, the special subframe is divided into 10 special subframes 0 to 9 in the case of a regular periodic prefix call CS, and in the case of an extended periodic prefix CS, A total of eight sub-frame configurations 0 to a special sub-frame configuration 7 can be distinguished.

8A is a diagram illustrating a special subframe structure in a general periodic prefix call. Referring to FIG. 8A, the special subframes 0 to 9 are configured to determine whether each symbol in the special subframe is a symbol D (or DwPTS) for the downlink, a symbol U (or UpPTS) for the uplink, G (or GP). 8A, the special sub-frame configuration determiner 260 determines whether a reference signal is detected in each of the symbols 4 (or 3), 7 (or 6), and 11 of the symbols in the special subframe Determines whether the symbol 4 (or the symbol 3), the symbol 7 (or the symbol 6) and the symbol 11 are each D according to the determination result, and determines that the special subframe structure belongs to any one of the four groups according to the determination result . This is based on the fact that the reference signal is detected only in the symbol D for the downlink in the special subframe.

For example, when the reference signal is detected in both the symbol 4, the symbol 7, and the symbol 11, the special subframe configuration determiner 260 in the general periodic prefix call assigns the special subframe configuration to the group 2 including the special subframe configuration 4 It can be determined that any one special sub-frame structure is included. As another example, when the reference signal is detected only in the symbol 4 and the symbol 7, the special sub-frame configuration determiner 260 sets the special sub-frame configuration to any one of the groups 1 to 3 included in the special sub- One special sub-frame configuration can be determined.

As another example, when the reference signal is detected only in the symbol 4, the special sub-frame configuration determiner 260 determines the special sub-frame configuration to any one of the special sub-frame configurations included in the group 3 including the special sub-frame configuration 9 . As another example, the special subframe configuration determiner 260 may include the special subframe configuration in group 0 including special subframe configurations 0 and 5, if no reference signal is detected in both symbol 4, symbol 7, It is possible to determine any one special sub-frame structure. At this time, the special sub-frame configuration determiner 260 may further determine whether a reference signal is detected in symbol 0 (or symbol 1, or symbol 2). The special sub-frame configuration determiner 260 further determines whether there is a reference signal in at least one of the symbol 8, the symbol 9, and the symbol 10, and transmits the group 1 to the group 1 corresponding to the special sub- -1, the group 1-2 corresponding to the special sub frame structure 2, 7, and the group 1-3 corresponding to the special sub frame structure 3, 8.

8B is a diagram illustrating a special subframe structure in the extended periodic prefix portion. Referring to FIG. 8B, the special subframe constructions 0 to 7 indicate whether each symbol in the special subframe is a symbol D (or DwPTS) for the downlink, a symbol U (or UpPTS) for the uplink, a symbol G (or GP). Referring to FIG. 8B, the special sub-frame configuration determiner 260 determines whether or not the reference signal in each of symbol 4 (or symbol 3), symbol 7 (or symbol 6 or symbol 5) (Or symbol 3), symbol 7 (or symbol 6 or symbol 5), and symbol 9 are each D according to whether or not the symbol 4 (or symbol 3) is detected, and determines the special sub- Quot; ". < / RTI > This is based on the fact that the reference signal is detected only in the symbol D for the downlink in the special subframe.

For example, when the reference signal is detected in both the symbol 4, the symbol 7, and the symbol 9, the special subframe configuration determiner 260 in the extended periodic prefix call assigns the special subframe configuration to the group 2 including the special subframe configuration 3 It can be determined that any one special sub-frame structure is included. As another example, when the reference signal is detected only in the symbol 4 and the symbol 7, the special sub-frame configuration determiner 260 sets the special sub-frame configuration to any one of the group 1 including the special sub-frame configurations 1, 2, One special sub-frame configuration can be determined.

As another example, when the reference signal is detected only in the symbol 4, the special sub-frame configuration determiner 260 determines the special sub-frame configuration as any special sub-frame configuration included in the group 3 including the special sub-frame configuration 7 . As another example, if the reference signal is not detected in both symbol 4, symbol 7, and symbol 9, the special subframe configuration determiner 260 includes the special subframe configuration in group 0 including special subframe configurations 0 and 4 It is possible to determine any one special sub-frame structure. At this time, the special sub-frame configuration determiner 260 may further determine whether a reference signal is detected in symbol 0 (or symbol 1, or symbol 2). In addition, the special sub-frame configuration determiner 260 further determines whether or not there is a reference signal in the symbol 8 so that the group 1 is divided into the group 1-1 corresponding to the special sub-frame configuration 1 and the special sub- And group 1-2 corresponding to " 6 ".

The special subframe configuration determiner 260 determines that the reference signal is detected in symbol 4, symbol 7 and symbol 11 (or symbol 0, symbol 4, symbol 7, and symbol 11) The special subframe configuration determiner 260 may determine whether the periodic prefix is normal or extended and determine whether the periodic prefix is normal or extended based on the determination result. It is possible to determine the configuration of the special sub-frame finally.

In other words, the special subframe configuration determiner 260 determines the type of the cyclic prefix of a plurality of symbols to be one of an Extended cyclic prefix type and a Normal cyclic prefix type, The structure of the special sub-frame can be determined based on the type.

For example, if the reference signal is detected in the symbol 4, the symbol 7 and the symbol 11 (or the symbol 0, the symbol 4, the symbol 7, and the symbol 11) when the periodic prefix is normal, Symbol 4, symbol 7, and symbol 9 (or symbol 0, symbol 4, symbol 7, and symbol 9) when the cyclic prefix is extended, and determines the special subframe structure according to the result. It is possible to determine whether or not the reference signal is detected and determine the special subframe structure according to the result.

As described above, in the case of the SSF, the presence or absence of the RS signal at a specific temporal position of the RS signal can be grasped to determine ten SSF frame structures into four groups. The presence or absence of RS can be judged by correlation with RS code, and it was possible to classify 10 SFF configurations into 4 according to the temporal position of RS. However, since the RSs of the 3GPP LTE / LTE-A are not transmitted for each OFDM symbol (for example, the symbols for the downlink and the GPs are not transmitted in the GP), only the SSF types set in the OFDM symbol unit It is hard to estimate and can be estimated only in the case of the four (or group) cases described above.

Since CP (Cyclic Prefix) can be used for more accurate SSF determination, since the accurate downward timing is already secured, the downlink CP correlation value greatly affects And the SS correlation can be finally determined by measuring CP correlation for each OFDM symbol for a sufficiently long period of time.

 The switching unit 270 may switch the uplink and downlink over time based on the determined uplink downlink configuration. At this time, the switching unit 270 generates a transmission / reception switching signal based on at least one of the determined uplink downlink configuration and the special subframe configuration, and based on the generated transmission / reception switching signal, Lt; / RTI >

At this time, the uplink downlink configuration (or type of TDD frame structure or type of TDD frame structure), as described above, may be used for uplink downlink configuration (or type of TDD frame structure or TDD frame structure) (Or type of TDD frame structure) 6, and the configuration of the special subframe may be any of the general special subframe configuration 0 to the general special subframe corresponding to the general periodic prefix call Frame structure 9, and an extended special sub-frame structure 0 to an extended special sub-frame structure 7 corresponding to an extended periodic prefix call.

The memory 280 stores data, information, or signals. In one example, the memory 280 stores the detected PSS, SSS, stores the determined downlink uplink configuration and special subframe configuration, and stores the measured periodic prefixes and results. One example of such a memory 280 includes a hard disk drive, a hard disk drive, a ROM (Read Only Memory), a RAM (Random Access Memory), a flash memory, a memory card, and the like existing inside or outside the repeater 20 do.

According to one embodiment of the present invention, the repeater 20 receives a primary synchronization through a PSS correlation from a signal of a base station 10 received through a hardware unit, and then, based on the primary synchronization, (Not shown) or a control unit (not shown) and stores the received data of the specific position or time required by the algorithm in the memory 280 for correlation to the SSS, RS, CP To calculate the Correlation. With this structure, not only the amount of data stored in the memory 280 can be minimized to minimize the required memory capacity, but also the portion that does not need high-speed signal processing is processed by SW, The repeater 20 can be implemented. 4, the communication unit 210, the PSS detection unit 211, and the memory 280 are connected to the hardware unit 210. The communication unit 210, the PSS detection unit 211, and the memory 280, And the remainder may be a software unit included in the control process.

9 is a flowchart illustrating an example of a process in which uplink downlink switching is performed. 9 is only an embodiment of the present invention, and thus the present invention is not limited to the operation of FIG. Further, steps S901 through S909 of FIG. 9 may be further divided into further steps, or combined into fewer steps, according to embodiments of the present disclosure. Also, some of the steps may be omitted as necessary, and the order between the steps may be changed. For example, only steps S901 to S905 and step S909 may be performed.

Referring to FIG. 9, in step S901, the repeater 20 can detect the main synchronization signal PSS using the signal of the base station 10. In step S902, the repeater 20 may perform step S903 if a main synchronization signal is detected, and perform step S901 again if a main synchronization signal is not detected. Further, in step S903, the repeater 20 can detect the secondary synchronization signal SSS using the signal of the base station 10. In step S904, the repeater 20 may perform step S905 if the secondary synchronization signal is detected, and perform step S901 again if the secondary synchronization signal is not detected.

Referring to FIG. 9, in step S905, the repeater 20 can determine the uplink downlink configuration using the synchronization signal and the reference signal. In step S906, the repeater 20 may perform step S907 if the uplink downlink configuration is determined, and perform step S901 again if the secondary synchronization signal is not detected.

Referring to FIG. 9, in step S907, the repeater 20 can determine a special subframe configuration using the periodic prefix call and the reference signal. In step S908, the repeater 20 may perform step S909 if the special subframe structure is determined, and perform step S901 again if the secondary synchronization signal is not detected. In step S909, the repeater 20 may switch between uplink and downlink using at least one of an uplink downlink configuration and a special subframe configuration. At this time, the repeater 20 can generate a transmission / reception switching signal for switching of the uplink and the downlink.

10 is an operational flow diagram illustrating an uplink downlink switching method in accordance with one embodiment of the present application. The uplink downlink switching method of FIG. 10 includes the steps of time series processing in the repeater 20 described with reference to FIGS. Therefore, the contents of the base station 20 described with reference to Figs. 1 to 9 also apply to the uplink downlink switching method of Fig. 10 even if omitted below.

In step S1001, the repeater 20 can receive the signal of the base station 10. In step S1002, the repeater 20 can determine whether or not a reference signal exists in the frame of the signal. In step S1003, the repeater 20 can determine the uplink downlink configuration corresponding to the base station and the user terminal according to the determination result. In step S1004, the repeater 20 can switch the downlink and the uplink over time based on the uplink downlink configuration.

According to one embodiment of the present application, step 1002 may be to determine whether a reference signal is present in at least one sub-frame of the plurality of sub-frames of the frame. Further, according to one embodiment of the present application, the uplink downlink switching method may further include a step (not shown) of detecting at least one synchronization signal from the signal after step S1001, Each of the frames may be distinguished from each other based on the synchronization signal, and step S1002 may be to determine whether or not a reference signal exists based on the synchronization signal. Also, according to one embodiment of the present invention, step 1002 may be to determine whether a reference signal is present in at least one subframe according to whether or not reference signal power is detected in at least one subframe.

Further, according to one embodiment of the present invention, the uplink downlink switching method may further include, after step S1003, a step (not shown) of determining a configuration of a special subframe of the frame, wherein step S1004 And to switch the uplink and downlink over time based on the determined uplink downlink configuration and the configuration of the special subframe. Further, according to one embodiment of the present invention, the uplink downlink switching method determines, after step S1003, whether or not a reference signal exists in at least one symbol among a plurality of symbols of a special subframe among a plurality of subframes of the frame (Not shown). In this case, the step of determining the configuration of the special subframe (not shown) may include a step of determining whether or not a reference signal exists in at least one symbol Lt; RTI ID = 0.0 > subframe < / RTI >

Also, according to an embodiment of the present invention, after determining (step) whether or not a reference signal exists in at least one symbol, a type of a cyclic prefix (CP) of a plurality of symbols is determined , Wherein the step of determining the configuration of the special subframe (not shown) may be to determine the configuration of the special subframe based on the determined type of periodic prefix call.

According to one embodiment of the present application, in step S1001, the repeater 20 can receive the signal of the base station 10. In step S1002, the repeater 20 can determine whether or not a reference signal exists in the frame of the signal. In step S1003, the repeater 20 can determine any one of the plurality of types of the time-division frame structure corresponding to the base station 10 and the user terminal 30 according to the determination result. In step S1004, the repeater 20 can switch the downlink and the uplink over time based on any one of the determined types.

In the above description, steps S1001 to S1004 may be further divided into additional steps or combined into fewer steps, according to an embodiment of the present invention. Also, some of the steps may be omitted as necessary, and the order between the steps may be changed.

The uplink downlink switching method described above may also be implemented in the form of a recording medium including instructions executable by a computer such as a program module executed by a computer. Computer readable media can be any available media that can be accessed by a computer and includes both volatile and nonvolatile media, removable and non-removable media. In addition, the computer-readable medium can include both computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Communication media typically includes any information delivery media, including computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave, or other transport mechanism.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

1: communication system
10: Base station
20: Repeater
30: User terminal
210:
220: Sync signal detector
230: Reference signal judgment unit
250: uplink downlink configuration determining unit
260: Special sub-frame configuration determining unit
270:
280: Memory

Claims (18)

A method for switching uplink and downlink in a repeater over time,
Receiving a signal from a base station;
Whether or not a reference signal (Reference Signal) exists in subframe 3, subframe 4, subframe 7 and subframe 9 as at least one subframe of subframe 0 to subframe 9, which is a plurality of subframes of the frame of the signal ;
Determining an uplink downlink configuration that the base station is using for communication with a user terminal in a plurality of uplink downlink configurations as a plurality of types of time division frame structures according to the determination result; And
And switching the uplink and downlink over time based on the determined uplink downlink configuration,
Wherein the step of determining includes determining that at least one subframe in which the reference signal exists is a downlink subframe used for downlink transmission based on a result of the determination in the determining step, Link configuration uplink Determine any one of downlink configurations 0 to 6,
When a reference signal exists in the subframe 3, the subframe 4, the subframe 7, and the subframe 9, the type of the time division frame structure is determined to be the uplink downlink configuration 5,
And determines the type of the time division frame structure as the uplink downlink configuration 2 when the reference signal exists only in the subframe 3, the subframe 4, and the subframe 9.
delete The method according to claim 1,
Further comprising: after said receiving, detecting at least one synchronization signal from said signal,
Wherein each of the plurality of sub-frames of the frame is separated from each other based on the synchronization signal,
Wherein the determining step determines whether the reference signal is present based on the synchronization signal.
The method of claim 3,
Each of the plurality of subframes is distinguished from each other according to a predetermined time interval from a start time,
Wherein the starting point is determined based on the synchronization signal.
The method according to claim 1,
Wherein the determining step determines whether the reference signal is present in the at least one subframe according to whether or not reference signal power is detected in at least one subframe among a plurality of subframes of the frame .
delete The method of claim 3,
Wherein the synchronization signal comprises a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS).
The method according to claim 1,
Further comprising the step of determining a configuration of a special sub-frame of the frame after determining the uplink downlink configuration,
Wherein the switching is to switch the uplink and downlink over time based on the determined uplink downlink configuration and the configuration of the special subframe.
8. The method of claim 7,
Determining whether a reference signal is present in at least one of the plurality of symbols of the special sub-frame among the plurality of sub-frames of the frame after determining the uplink downlink configuration, Including,
Wherein the determining of the configuration of the special subframe determines a configuration of a special subframe according to a determination result of whether or not a reference signal exists in the at least one symbol.
10. The method of claim 9,
Wherein the plurality of symbols comprises symbols 0 to 13,
Wherein the at least one symbol comprises a symbol 0, a symbol 4, a symbol 7 and a symbol 11.
10. The method of claim 9,
Further comprising determining a type of a cyclic prefix (CP) of the plurality of symbols after determining whether a reference signal exists in the at least one symbol,
Wherein the determining of the configuration of the special subframe determines the configuration of the special subframe based on the determined type of the periodic prefix call.
12. The method of claim 11,
Wherein the type of the cyclic prefix call includes an Extended cyclic prefix call type and a Normal cyclic prefix call type.
9. The method of claim 8,
The uplink downlink configuration is any one of uplink downlink configuration 0 to uplink downlink configuration 6,
The configuration of the special subframe includes a general special subframe configuration 0 to a general special subframe configuration 9 corresponding to a general cyclic prefix call and an extended special subframe configuration 0 to an extended special subframe configuration 9 corresponding to an extended cyclic prefix call, RTI ID = 0.0 > 7. ≪ / RTI >
The method according to claim 1,
Wherein switching the uplink and downlink comprises generating a transmit / receive switching signal based on the determined uplink downlink configuration, and switching the uplink and downlink over time based on the generated transmit / receive switch signal , Way.
1. A repeater for switching between uplink and downlink over time, comprising:
A receiving unit for receiving a signal of a base station;
Whether or not a reference signal (Reference Signal) exists in subframe 3, subframe 4, subframe 7 and subframe 9 as at least one subframe of subframe 0 to subframe 9, which is a plurality of subframes of the frame of the signal A reference signal determination unit for determining a reference signal;
Determining, based on the determination result, a plurality of types of time division frame structures for uplink downlink configuration used by the base station for communication with a user terminal during a plurality of uplink downlink configurations, A downlink configuration determining unit; And
And a switching section for switching uplink and downlink over time based on the determined uplink downlink configuration,
Wherein the uplink downlink configuration determining unit determines the downlink subframe based on the result of determination by the reference signal determining unit that the at least one subframe in which the reference signal exists is a downlink subframe used for downlink transmission, Uplink downlink configuration 0 to 6, which is an uplink downlink configuration of the uplink downlink configuration,
When a reference signal exists in the subframe 3, the subframe 4, the subframe 7, and the subframe 9, the type of the time division frame structure is determined to be the uplink downlink configuration 5,
And determines a type of the time division frame structure as the uplink downlink configuration 2 when the reference signal exists only in the subframe 3, the subframe 4, and the subframe 9.
16. The method of claim 15,
The reference signal determination unit may further include a synchronization signal detection unit for detecting at least one synchronization signal from the signal,
Wherein each of the plurality of sub-frames is separated from each other based on the synchronization signal.
16. The method of claim 15,
Further comprising: a special sub-frame configuration determining unit for determining a configuration of a special sub-frame of the frame,
Wherein the switching unit switches the uplink and downlink over time based on the determined uplink downlink configuration and the configuration of the special subframe.
delete

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