KR20170052456A - Methods for signal transmission and reception in a wireless communication system over high frequency bands and apparatuses thereof - Google Patents

Abstract

The present invention relates to a method and an apparatus for transmitting and receiving a signal in a mobile communication system using a high frequency band of 28 GHz or the like. According to the embodiments of the present invention, a base station transmits multiple PSSs/SSSs to which different beams are applied, and a terminal checks beam identifier information included in the PSS/SSS to check where the PSS/SSS is received from and obtain time-frequency synchronization corresponding to the received PSS/SSS. Also, a beam reference signal (beam RS) applied with the same beam as that of the PSS/SSS is transmitted from a time position which is not an additional control area so that a terminal measures a state of a channel by using a reference signal applied to the beam.

Description

TECHNICAL FIELD [0001] The present invention relates to a method and apparatus for signal transmission and reception for a high-frequency mobile communication system,

The embodiments are directed to a method and apparatus for transmitting and receiving signals in a high-frequency mobile communication system.

The mobile communication system has evolved into a high-speed and high-quality wireless packet data communication system for providing data services and multimedia services, apart from providing initial voice-oriented services.

A variety of mobile communication standards such as High Speed Downlink Packet Access (HSDPA), High Speed Uplink Packet Access (HSUPA), Long Term Evolution (LTE) and Long Term Evolution Advanced (3GPP) It is a system developed to efficiently support data transmission and maximizes the capacity of the wireless system by utilizing various wireless connection technologies. The LTE-Advanced system is an advanced wireless system of LTE systems with enhanced data transmission capabilities compared to LTE.

The LTE-Advanced system utilizes the advantages of each technology by applying Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiple Access (OFDMA).

Of these, OFDMA provides scheduling of different UEs on one frequency axis, thereby providing an advantage that a capacity increase can be obtained. In other words, if the characteristics of the channel varying with time and the characteristics of the channel varying with frequency are used together, a large capacity gain can be obtained by combining with a proper scheduling method.

On the other hand, when OFDM is used in a frequency band of 28 GHz which is higher than the LTE system aiming at 6 GHz or less, the influence of phase noise between subcarriers becomes large, which requires a larger subcarrier interval than that of the existing LTE system. Also, at higher frequencies, the degree of attenuation of the signal becomes larger, and it is necessary to transmit a stronger signal in a specific direction by applying a beamforming technique to the signal.

Accordingly, a new time-frequency resource utilization structure and a signal transmission / reception method between a terminal and a base station that can be used in a high-frequency mobile communication system using a higher frequency band than an LTE system are required.

It is an object of the present embodiments to provide a resource utilization structure and a signal transmission / reception method between a terminal and a base station, which enable data transmission / reception using a given time-frequency resource when OFDM is used in a high-frequency mobile communication system.

In one aspect, the present embodiments provide a method for a terminal to receive a signal in a high frequency mobile communication system, comprising: receiving a beam-applied synchronization signal through a resource comprised of subcarriers that are multiples of 15 kHz; Identifying the received beam identifier information and the cell identifier information, and acquiring time-frequency synchronization based on the synchronization signal for which the beam identifier information is confirmed.

In the high frequency mobile communication system, the signal reception method of the terminal may further include receiving a beam reference signal to which the same beam as the synchronization signal is applied, in the same frequency band as the frequency band in which the synchronization signal is received.

At this time, the beam reference signal may be received at a position other than the first symbol from the first symbol of the subframe.

Further, the beam reference signal may be received in a subframe in which the synchronization signal is not received.

In a method of receiving a signal in a high frequency mobile communication system, in a case where a synchronization signal for a plurality of beams is transmitted, the mobile station operates in a high frequency mobile communication system based on the number of resource blocks used for the synchronization signal and the interval of the synchronization signal The minimum system bandwidth that can be determined.

When a synchronization signal for a plurality of beams is transmitted, based on a time interval of a synchronization signal and a time required to transmit all synchronization signals for a plurality of beams, a minimum time required for the terminal to acquire synchronization of a specific cell Can be determined.

In another aspect, the present embodiments provide a method for a base station to transmit a signal in a high frequency mobile communication system, the method comprising: generating one or more synchronization signals including beam identifier information and cell identifier information; Applying different beams according to the identifier information, and distributing the one or more synchronization signals to which the beam is applied, at different positions on the time-frequency and transmitting the signals.

According to another aspect of the present invention, there is provided a terminal for receiving a signal from a base station in a high frequency mobile communication system, comprising: a communication unit for receiving a synchronization signal to which a beam is applied through a resource composed of subcarriers that are multiples of 15 kHz from the base station; And acquiring time-frequency synchronization based on the synchronization signal in which the beam identifier information is confirmed by checking the beam identifier information and the cell identifier information included in the header information.

In another aspect, the present embodiments provide a base station for transmitting a signal to a terminal in a high-frequency mobile communication system, the base station generating at least one synchronization signal including beam identifier information and cell identifier information, A controller for applying different beams and distributing one or more synchronization signals to which beams are applied to different positions on a time-frequency axis, and a communication unit for transmitting one or more synchronization signals to which beams are applied.

According to the present embodiments, in the high-frequency mobile communication system, by transmitting / receiving the PSS / SSS to which the beam is applied, the terminal can check the beam identifier included in the PSS / SSS and check the position of the PSS / So that the corresponding time-frequency synchronization can be obtained.

According to the present embodiments, control information can be transmitted / received only in a specific resource block in a form similar to a resource block in which data is transmitted without considering a separate control domain for each subframe.

1 is a diagram illustrating time and frequency resources in an LTE / LTE-Advanced system.
2 is a diagram illustrating time-frequency parameters used in LTE.
3 is a diagram illustrating a location of a PSS / SSS used in an LTE system operating as a TDD.
4 is a diagram illustrating radio resources of one subframe and one resource block, which are the minimum units for downlink scheduling in the LTE / LTE-Advanced system.
5 is a diagram illustrating a method of using each region and a signal in a radio resource of one sub-frame and one resource block, which are the minimum units for downlink scheduling in the LTE / LTE-Advanced system.
6 is a diagram for explaining an operation of confirming scheduling information using a PDCCH region.
7 is a diagram illustrating time-frequency resources and corresponding system parameters for subcarrier spacing of 150 kHz and 75 kHz.
Fig. 8 is a diagram for explaining transmission and reception of a synchronizing signal when a high-frequency signal is used.
FIG. 9 is a diagram for explaining a radio resource structure for downlink to which the present embodiments are applied.
FIG. 10 is a diagram for explaining a radio resource structure according to the present embodiments.
11 is a flowchart illustrating a method of receiving a signal in a high frequency mobile communication system according to the present embodiments.
12 is a flowchart illustrating a method of transmitting a signal by a base station in the high frequency mobile communication system according to the present embodiments.
13 is a diagram illustrating a configuration of a terminal according to the present embodiments.
FIG. 14 is a diagram illustrating a configuration of a base station according to the present embodiments.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Herein, the MTC terminal may mean a terminal supporting low cost (or low complexity) or a terminal supporting coverage enhancement. In this specification, the MTC terminal may mean a terminal supporting low cost (or low complexity) and coverage enhancement. Alternatively, the MTC terminal may refer to a terminal defined in a specific category for supporting low cost (or low complexity) and / or coverage enhancement.

In other words, the MTC terminal in this specification may mean a newly defined 3GPP Release-13 low cost (or low complexity) UE category / type for performing LTE-based MTC-related operations. Alternatively, the MTC terminal may support the enhanced coverage over the existing LTE coverage, the UE category / type defined in the existing 3GPP Release-12 or lower that supports low power consumption, or the newly defined Release-13 low cost Or low complexity UE category / type.

The wireless communication system in the present invention is widely deployed to provide various communication services such as voice, packet data and the like. A wireless communication system includes a user equipment (UE) and a base station (BS, or eNB). The user terminal in this specification is a comprehensive concept of a terminal in wireless communication. It is a comprehensive concept which means a mobile station (MS), a user terminal (UT), an SS (User Equipment) (Subscriber Station), a wireless device, and the like.

A base station or a cell generally refers to a station that communicates with a user terminal and includes a Node-B, an evolved Node-B (eNB), a sector, a Site, a BTS A base transceiver system, an access point, a relay node, a remote radio head (RRH), a radio unit (RU), and a small cell.

That is, in the present specification, a base station or a cell has a comprehensive meaning indicating a part or function covered by BSC (Base Station Controller) in CDMA, Node-B in WCDMA, eNB in LTE or sector (site) And covers various coverage areas such as megacell, macrocell, microcell, picocell, femtocell and relay node, RRH, RU, and small cell communication range.

Since the above-mentioned various cells exist in the base station for controlling each cell, the base station can be interpreted into two meanings. i) a device itself providing a megacell, a macrocell, a microcell, a picocell, a femtocell, or a small cell in relation to a wireless region, or ii) the wireless region itself. i indicate to the base station all the devices that interact to allow the devices providing the given wireless region to be controlled by the same entity or to configure the wireless region as a collaboration. An eNB, an RRH, an antenna, an RU, an LPN, a point, a transmission / reception point, a transmission point, a reception point, and the like are exemplary embodiments of a base station according to a configuration method of a radio area. ii) may indicate to the base station the wireless region itself that is to receive or transmit signals from the perspective of the user terminal or from a neighboring base station.

Therefore, a base station is collectively referred to as a base station, collectively referred to as a megacell, macrocell, microcell, picocell, femtocell, small cell, RRH, antenna, RU, low power node do.

Herein, the user terminal and the base station are used in a broad sense as the two transmitting and receiving subjects used to implement the technical or technical idea described in this specification, and are not limited by a specific term or word. The user terminal and the base station are used in a broad sense as two (uplink or downlink) transmitting and receiving subjects used to implement the technology or technical idea described in the present invention, and are not limited by a specific term or word. Here, an uplink (UL, or uplink) means a method of transmitting / receiving data to / from a base station by a user terminal, and a downlink (DL or downlink) .

There are no restrictions on multiple access schemes applied to wireless communication systems. Various multiple access schemes such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), OFDM-FDMA, OFDM- Can be used. An embodiment of the present invention can be applied to asynchronous wireless communication that evolves into LTE and LTE-Advanced via GSM, WCDMA, and HSPA, and synchronous wireless communication that evolves into CDMA, CDMA-2000, and UMB. The present invention should not be construed as limited to or limited to a specific wireless communication field and should be construed as including all technical fields to which the idea of the present invention can be applied.

A TDD (Time Division Duplex) scheme in which uplink and downlink transmissions are transmitted using different time periods, or an FDD (Frequency Division Duplex) scheme in which they are transmitted using different frequencies can be used.

In systems such as LTE and LTE-Advanced, the uplink and downlink are configured on the basis of one carrier or carrier pair to form a standard. The uplink and the downlink are divided into a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator CHannel (PCFICH), a Physical Hybrid ARQ Indicator CHannel, a Physical Uplink Control CHannel (PUCCH), an Enhanced Physical Downlink Control Channel (EPDCCH) Transmits control information through the same control channel, and is configured with data channels such as PDSCH (Physical Downlink Shared CHannel) and PUSCH (Physical Uplink Shared CHannel), and transmits data.

On the other hand, control information can also be transmitted using EPDCCH (enhanced PDCCH or extended PDCCH).

In this specification, a cell refers to a component carrier having a coverage of a signal transmitted from a transmission point or a transmission point or a transmission / reception point of a signal transmitted from a transmission / reception point, and the transmission / reception point itself .

The wireless communication system to which the embodiments are applied may be a coordinated multi-point transmission / reception system (CoMP system) or a coordinated multi-point transmission / reception system in which two or more transmission / reception points cooperatively transmit signals. antenna transmission system, or a cooperative multi-cell communication system. A CoMP system may include at least two multipoint transmit and receive points and terminals.

The multi-point transmission / reception point includes a base station or a macro cell (hereinafter referred to as 'eNB'), and at least one mobile station having a high transmission power or a low transmission power in a macro cell area, Lt; / RTI >

Hereinafter, a downlink refers to a communication or communication path from a multipoint transmission / reception point to a terminal, and an uplink refers to a communication or communication path from a terminal to a multiple transmission / reception point. In the downlink, a transmitter may be a part of a multipoint transmission / reception point, and a receiver may be a part of a terminal. In the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of multiple transmission / reception points.

Hereinafter, a situation in which a signal is transmitted / received through a channel such as PUCCH, PUSCH, PDCCH, EPDCCH, and PDSCH is expressed as 'PUCCH, PUSCH, PDCCH, EPDCCH and PDSCH are transmitted and received'.

In the following description, the description that the PDCCH is transmitted or received or the signal is transmitted or received through the PDCCH may be used to mean transmitting or receiving the EPDCCH or transmitting or receiving the signal through the EPDCCH.

That is, the physical downlink control channel described below may mean a PDCCH, an EPDCCH, or a PDCCH and an EPDCCH.

Also, for convenience of description, the PDCCH, which is an embodiment of the present invention, may be applied to the PDCCH, and the PDCCH may be applied to the portion described with the EPDCCH.

Meanwhile, the High Layer Signaling described below includes RRC signaling for transmitting RRC information including RRC parameters.

The eNB performs downlink transmission to the UEs. The eNB includes a physical downlink shared channel (PDSCH) as a main physical channel for unicast transmission, downlink control information such as scheduling required for reception of a PDSCH, A physical downlink control channel (PDCCH) for transmitting scheduling grant information for transmission in a Physical Uplink Shared Channel (PUSCH). Hereinafter, the transmission / reception of a signal through each channel will be described in a form in which the corresponding channel is transmitted / received.

The mobile communication system has evolved into a high-speed and high-quality wireless packet data communication system for providing data service and multimedia service apart from providing initial voice-oriented service. A variety of mobile communication standards such as High Speed Downlink Packet Access (HSDPA), High Speed Uplink Packet Access (HSUPA), Long Term Evolution (LTE) and Long Term Evolution Advanced (3GPP) It was developed to support data transfer service. In particular, LTE system is developed to efficiently support high - speed wireless packet data transmission and maximizes the capacity of wireless system by utilizing various wireless connection technologies. The LTE-Advanced system is an advanced wireless system of LTE systems with enhanced data transmission capabilities compared to LTE.

The above-mentioned LTE generally refers to base station and terminal equipment corresponding to Release 8 or Release 9 of 3GPP standards body, and LTE-Advanced refers to base station and terminal equipment corresponding to Release 10 of 3GPP standards body. The 3GPP standard group has been working on standardization of LTE-Advanced system for subsequent releases with improved performance based on this standardization.

LTE / LTE-Advanced systems utilize the advantages of each technology by applying multiple input multiple output (MIMO) and orthogonal frequency division multiple access (OFDMA) technologies. First, MIMO that transmits a radio signal using a plurality of transmit antennas includes MU-MIMO (Single User MIMO) that transmits data to a plurality of UEs using the same time / frequency resource as SU-MIMO Multi-User MIMO). In case of SU-MIMO, a plurality of transmission antennas transmit a radio signal to one receiver to a plurality of spatial layers. In this case, the receiver must have a plurality of reception antennas to support a plurality of spatial layers. On the other hand, in the case of MU-MIMO, a plurality of transmission antennas transmit a radio signal to a plurality of receivers in a plurality of spatial layers. MU-MIMO has the advantage that the receiver does not need a plurality of receiving antennas as compared with SU-MIMO. However, the disadvantage is that mutual interference can occur between radio signals for different receivers because they transmit radio signals to a plurality of receivers on the same frequency and time resources.

One of the main factors for achieving capacity increase through the OFDMA scheme is scheduling of different UEs on the frequency axis. That is, when a channel is changed in frequency, such as a characteristic in which a channel changes with time, a capacity gain can be obtained in combination with an appropriate scheduling method.

Figure 1 illustrates time and frequency resources in an LTE / LTE-Advanced system.

1, a radio resource transmitted from an evolved NodeB (eNB) to a user equipment (UE) is divided into resource blocks (RBs) 110 on the frequency axis. On the time axis, (Subframe) 120. The subframe 120 is divided into units.

In the LTE / LTE-Advanced system, the resource block 110 is generally composed of 12 subcarriers, the subcarrier interval is 15 kHz, and one resource block 110 occupies 180 kHz.

On the other hand, in the LTE / LTE-Advanced system, the subframe 120 generally includes 14 OFDM symbol intervals and occupies a time interval of 1 msec.

Here, each OFDM symbol interval includes a cyclic prefix (CP), the first and eighth OFDM symbols include a CP having a length of 160Ts, and the remaining OFDM symbols include a CP having a length of 144Ts. Here, Ts corresponds to 1 / (15000x2048) seconds as the basic time unit of the LTE / LTE-Advanced system.

In the LTE / LTE-Advanced system, resources can be allocated in units of subframes 120 in the time axis and resources can be allocated in units of resource blocks 110 in the frequency axis.

Figure 2 details the time-frequency parameters used in LTE.

In a conventional LTE system, a base station transmits a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) at a predetermined time-frequency location in order to acquire time-frequency synchronization from a terminal to a specific cell. .

3 shows the location of a PSS / SSS used in an LTE system operating in TDD.

Referring to FIG. 3, in the LTE system operating as TDD, the PSS is located in the third OFDM symbol of subframe # 1 and subframe # 6, and the SSS is located in the last OFDM symbol of slot # 1 and slot # 11.

FIG. 4 illustrates radio resources of one subframe and one resource block, which are the minimum units for downlink scheduling in the LTE / LTE-Advanced system.

Referring to FIG. 4, the downlink scheduling unit of the LTE / LTE-Advanced system includes one subframe 210 on the time axis and one resource block 220 on the frequency axis.

Such radio resources are composed of 12 subcarriers in the frequency domain and 14 OFDM symbols in the time domain, thereby providing a total of 168 natural frequency and time positions.

In LTE / LTE-Advanced, the natural frequencies and time positions shown in FIG. 2 are referred to as resource elements (REs). In addition, one subframe consists of two slots (Slots) each consisting of 7 OFDM symbols.

A plurality of different types of signals may be transmitted to the radio resource shown in FIG.

1. Cell-specific reference signal (CRS) 230: A reference signal transmitted for channel measurement of all UEs belonging to a specific cell

2. DMRS (Modulation Reference Signal) (240, 241): A reference signal transmitted for decoding data of a specific terminal

3. Channel Status Information Reference Signal (CSI-RS) 270: A reference signal transmitted to a terminal belonging to a specific signal transmission point. A plurality of transmission points may be included in one cell, and a plurality of CSI-RSs may be transmitted in one cell

4. PDSCH (Physical Downlink Shared Channel) 250: A data channel transmitted in the downlink, transmitted using a resource unit in which a base station uses data to transmit data to a mobile station and a reference signal is not transmitted in the data region of FIG. 4 being

5. Control channel (PDCCH, PCFICH, PHICH) 260: ACK / NACK transmission for control information or uplink HARQ operation required for the UE to receive the PDSCH. The control channel can occupy three OFDM symbols in each subframe, and the number of OFDM symbols for the corresponding control channel is reported to the UE through the PCFICH

In addition to the above-mentioned signals, the LTE-Advanced system can set muting so that the CSI-RS 270 transmitted by another base station can be received without interference to the terminals of the corresponding cell.

The muting may be applied at a location where the CSI-RS 270 can be transmitted. Generally, the UE receives the data signal by skipping the radio resource. In LTE-Advanced systems, muting is also referred to as zero-power CSI-RS. The muting is applied to the location of the CSI-RS 270 and the transmit power is zero (0) and no signal is transmitted.

The CSI-RS 270 can be transmitted using a part of the positions indicated by A, B, C, D, E, F, G, H, I, J according to the number of antennas transmitting the CSI- have. Also, muting can be applied to a part of the positions indicated by A, B, C, D, E, F, G, H,

The number of antenna ports supported by the LTE-Advanced system is 2, 4, and 8, and the CSI-RS can be transmitted using 2, 4, and 8 resource units, respectively. In the case where the number of antenna ports is two, the CSI-RS 270 is transmitted in half of the specific pattern in FIG. 4. When the number of antenna ports is four, the CSI-RS is transmitted to all the specific patterns. The CSI-RS is transmitted using the consecutive patterns. On the other hand, muting is done in one pattern unit.

FIG. 5 shows a method of using each region and a signal in a radio resource of one sub-frame and one resource block, which is a minimum unit for downlink scheduling in an LTE / LTE-Advanced system.

In the LTE / LTE-Advanced system, the UE checks the PDCCH (Physical Downlink Control Channel) every subframe and checks whether data (PDSCH) is transmitted in the corresponding subframe.

As described above, the PDCCH can occupy one to three OFDM symbol regions in each subframe, and the UEs can receive a Physical Control Format Indicator Channel (PCFICH) to check how many OFDM symbols are used as PDCCHs have.

That is, the BS sets the PCFICH to 1, 2, or 3 according to the size of the control channel required in a specific subframe, transmits the PDCCH to the UEs in the cell, and transmits the PDCCH in an area corresponding to the set value. Also, the PDCCH is transmitted over the entire system band, and the scheduling information to a specific terminal is uniformly spread over the entire system band.

The scheduling information included in the PDCCH includes some or all of the following information for the UEs receiving data in the corresponding subframe:

● PDSCH resource allocation information

● Modulation method and coding rate information

● HARQ information

● Retransmission / initial transmission classification information

Referring to FIG. 6, the UE checks a PDCCH area ranging from one to three OFDM symbols in a specific subframe to check whether a PDSCH to be transmitted to the UE is scheduled.

If scheduling occurs, it checks which resource blocks the corresponding PDSCH is located on the frequency, and performs decoding by receiving the PDSCH from the remaining OFDM symbols outside the control region for the corresponding resource blocks in the corresponding subframe.

FIG. 6 shows a case where M UEs confirm PDSCH scheduling in a specific subframe, and the PDSCH position to be received by each UE is identified by information in the PDCCH existing in all bands in all the UEs of the corresponding cell.

Also, in a conventional LTE / LTE-Advanced system, a UE can decode a whole data unit by confirming a PDCCH in a front OFDM symbol of a specific subframe and receiving a PDSCH in all OFDM symbols after the rest. That is, in the LTE / LTE-Advanced system, the data reception unit of the UE is 1 ms in one subframe.

Since the LTE / LTE-Advanced system is designed assuming that the data reception unit of the UE is 1 ms in the frequency band of 6 GHz or less, the time-frequency resource structure and the signals for utilizing the resource are designed as described above.

However, in a mobile communication system using OFDM in a high frequency band such as 28 GHz, the influence of phase noise between subcarriers increases, requiring a larger subcarrier interval than an existing LTE system aiming at less than 6 GHz. Also, at higher frequencies, the degree of signal attenuation increases with distance, so it is necessary to transmit a stronger signal in a specific direction by applying a beamforming technique to the signal.

Accordingly, the present embodiments provide a new time-frequency resource utilization structure that can be used in a high-frequency mobile communication system and a signal transmission / reception method of the terminal and the base station.

In particular, the present embodiments provide a resource utilization structure for performing data transmission / reception using a given time-frequency resource when OFDM is used in a high-frequency mobile communication system using a frequency band of several tens of GHz, And a signal transmission / reception method.

As described above, in the frequency band of several tens of GHz, the effect of phase noise between subcarriers becomes large, and a large subcarrier interval is required. Further, in the frequency band of several tens of GHz, there is a usable frequency of several hundreds of MHz, and it is necessary to maintain a large subcarrier interval.

In order to maintain a large subcarrier interval with a time-frequency structure similar to that of existing LTE in the new high-frequency mobile communication system, the present embodiments are set to a value corresponding to a multiple of 15 kHz, which is the subcarrier interval of LTE.

That is, considering that the channel environment in the frequency band around approximately 30 GHz is considered, it is determined that it is efficient to have the subcarrier interval of approximately 5 times or 10 times. Thus, the present embodiments consider the subcarrier interval of 75 kHz or the subcarrier interval of 150 kHz .

7 shows time-frequency resources and corresponding system parameters for subcarrier intervals of 150 kHz and 75 kHz, respectively.

Referring to FIG. 7, assuming an OFDM system using a 2048 FFT, the entire system band is composed of 200 MHz and 100 MHz, and one subframe may be composed of 0.1 ms and 0.2 ms, respectively. Then, in a high-frequency mobile communication system, a resource block, a sub-frame, and a radio frame structure of the same type as LTE / LTE-Advanced can be basically taken.

That is, the resource block is composed of 12 subcarriers, the subframe is composed of 14 OFDM symbols, and the radio frame is composed of 10 subframes.

In a high-frequency mobile communication system, signal attenuation due to distance is significant, so it is necessary to apply beamforming that gives directivity to all transmission signals in order to compensate for the attenuation.

That is, a beam is formed and transmitted to a signal to collect the intensity of the signal in a specific direction, and when the signal is farther from the specific direction, the signal is weak. In other words, in a high-frequency mobile communication system, it is necessary to form and transmit signals in signals that are assumed to be transmitted in all directions in a cell in the existing LTE / LTE-Advanced.

Therefore, PSS / SSS is a part that needs different design in high-frequency mobile communication system for existing LTE / LTE-Advanced.

In the existing LTE / LTE-Advanced, the PSS / SSS is transmitted so that it can detect even signals in a specific cell. Therefore, only one PSS / SSS is required for each cell. However, in the high frequency mobile communication system, And a plurality of PSS / SSSs must be operated per cell in order to allow the UEs in the entire cell area to detect the PSS / SSS.

Assuming that the number of beams to be applied to the PSS / SSS is N, a certain cell must operate N PSS / SSS. In addition, when the UE receives a specific PSS / SSS, it must be able to confirm which beam the corresponding PSS / SSS corresponds to, thereby accurately acquiring the time-frequency synchronization of the corresponding cell.

8 shows a situation in which 16 beams are applied to a PSS / SSS and a PSS / SSS to which each beam is applied is divided and transmitted at different positions on time-frequency.

Referring to FIG. 8, a specific beam is applied to one PSS / SSS, and the PSS / SSS includes cell identifier information and beam identifier information.

When the UE confirms a specific PSS / SSS, the UE confirms the beam identifier, and the UE receives the PSS / SSS corresponding to the precisely located position and acquires the corresponding time-frequency synchronization.

Considering the number of resource blocks used in the PSS / SSS transmitted at the corresponding time and the interval between each PSS / SSS in the case where the PSS / SSS for a plurality of beams are simultaneously transmitted in the frequency domain, The minimum system bandwidth that can be operated in the system can be calculated.

Also, when transmitting PSS / SSS for a plurality of beams in the time domain, the interval between adjacent PSSs / SSSs can be 10 or 5 subframes and it is necessary to transmit PSS / SSSs for all beams Corresponds to the minimum time required for the UE to acquire the synchronization of a particular cell.

The time for acquiring the corresponding cell synchronization is shown as a sweeping period in FIG. 8. Assuming that the interval between PSS and SSS is 10 subframes in FIG. 8, 4 ms corresponds to a sweeping period in case of 75 ms or 8 ms or 150 kHz .

In a high-frequency mobile communication system, a beam is also formed in signals that are assumed to be transmitted in all directions in a cell in a conventional LTE / LTE-Advanced, and another part requiring a new consideration is transmitted in a conventional LTE / LTE- 1 < th > OFDM symbol of the frame.

In the existing LTE / LTE-Advanced, the same structure can not be used in the high-frequency mobile communication system because the corresponding control domain signals are transmitted in such a manner that all signals in a specific cell can be detected.

In the conventional LTE / LTE-Advanced, control information is transmitted to the front OFDM symbols of a specific subframe in order to reduce the reception delay of the UE. However, in the high frequency mobile communication system, the interval between subframes is 0.1 ms or 0.2 ms Because it is short, you no longer need to use that method.

Therefore, in a high-frequency mobile communication system, control information can be transmitted / received only in a specific resource block region in a form similar to resource blocks in which data is transmitted, without having to have a separate control region transmitted in every system band for each subframe.

That is, in a high-frequency mobile communication system, it is not necessary to consider a separate control region while designing various signals transmitted in a specific resource block for data transmission.

In a high-frequency mobile communication system, a CRS is another part that requires a new consideration as a beam is formed and transmitted in signals that are assumed to be transmitted in all directions in a cell in a conventional LTE / LTE-Advanced.

As described above, in the LTE / LTE-Advanced, the CRS is used for precise time-frequency synchronization, RRM measurement and terminal channel measurement while being transmitted over the entire band. However, since high-frequency mobile communication systems require beam forming, CRS is basically difficult to use. Therefore, in the high-frequency mobile communication system, it is necessary to use a new RS formed with a beam different from the existing CRS, and the new RS needs to take charge of some of the CRS functions. In the present invention, the new RS is referred to as a beam reference signal (Beam RS).

In addition, since the CSI-RS and DMRS transmitted in the resource block are already designed to be applicable to beams, the structure of the existing LTE will be sufficiently reused.

FIG. 9 is a summary of the above description, and FIG. 10 shows a resource block structure of a high-frequency mobile communication system in consideration thereof.

Referring to FIG. 10, the control area used in the existing LTE / LTE-Advanced is not used. In addition, the beam reference signal (Beam RS) is transmitted in the same frequency band as CRS port 0 of the existing LTE / LTE-Advanced system in a specific resource block, and the same beamforming as the PSS / SSS transmitted in the same frequency domain To be applied.

Here, the most recently transmitted PSS / SSS includes the same subframe. That is, at least a beam reference signal (Beam RS) is transmitted in the subframe in which the PSS / SSS is transmitted, and a beam applied to each beam reference signal (Beam RS) is the same beam as the PSS / SSS transmitted in the same frequency domain.

As described above, in the high-frequency mobile communication system according to the present embodiments, the time position of the beam reference signal (Beam RS) may be different from that of the existing CRS port 0 as a separate control region is not used in the resource block.

In addition, the PSS / SSS and the beam reference signal (Beam RS) are not transmitted in all the subframes but only in the subframes in which the time-frequency synchronization and RRM measurement of the UE are required. It may also be possible that only a beam reference signal (Beam RS) is transmitted in a subframe in which PSS / SSS is not transmitted, if necessary.

The DMRS and CSI-RS shown in FIG. 10 are assumed to be able to adjust the time position without using the control domain, but the operation method is the same as that of the existing LTE / LTE-Advanced.

FIG. 11 illustrates a method for a terminal to receive a signal in a high-frequency mobile communication system according to the present embodiments.

Referring to FIG. 11, a UE according to the present embodiment receives a PSS / SSS to which a beam is applied from a base station (S1100).

Multiple PSSs / SSSs can be distributed and transmitted at different locations on the time-frequency with different beams applied.

In addition, it may receive a beam reference signal (Beam RS) to which the same beam as the beam applied to the PSS / SSS is applied in the same frequency band as the frequency band in which the PSS / SSS is received.

At this time, the beam reference signal Beam RS is not transmitted in the front OFDM symbol of the specific subframe, but the time position can be transmitted differently from the existing CRS port 0.

Upon receiving the PSS / SSS, the UE checks the beam identifier information and cell identifier information included in the PSS / SSS (S1110).

The terminal can check the beam identifier information to determine exactly which position the terminal has received the PSS / SSS. Then, time-frequency synchronization corresponding to the received PSS / SSS is acquired (S1120).

Therefore, according to the present embodiments, in the high frequency mobile communication system in which the terminal receives the PSS / SSS to which the beam is applied and confirms the beam identifier information, the terminal can acquire the time-frequency synchronization from the PSS / SSS .

FIG. 12 shows a method of transmitting a signal by a base station in the high-frequency mobile communication system according to the present embodiments.

Referring to FIG. 12, the base station according to the present embodiment generates a PSS / SSS including beam identifier information and cell identifier information (S1200).

The base station applies different beams to a plurality of PSSs / SSSs (S1210) and adds a beam reference signal (Beam RS) transmitted in the same frequency band as the frequency band in which the PSS / SSS is transmitted to the same beam Can be applied.

The base station distributes a plurality of PSSs / SSSs to which different beams are applied to different positions on a time-frequency basis and transmits them (S1220).

Also, the base station may transmit a beam reference signal (Beam RS) with the same beam as the PSS / SSS, and the beam reference signal (Beam RS) may be transmitted at a position different from the existing CRS port 0.

FIG. 13 shows a configuration of a terminal 1300 according to the present embodiments.

13, a communication unit 1310 of a terminal 1300 receives a signal such as a PSS / SSS, a reference signal RS, and data transmitted by a base station and transmits the received signal to a controller 1320.

The control unit 1320 acquires synchronization from the reception signals transmitted from the communication unit 1310, receives the RS according to the usage of the RS, and decodes the data using the channel estimation information according to the RS.

The system synchronization unit 1321, the channel estimation unit 1322, and the data decoding unit 1323 may be a part of the control unit 1320 or may exist separately.

FIG. 14 shows a configuration of a base station 1400 according to the present embodiments.

14, the communication unit 1420 of the base station 1400 transmits a signal such as a PSS / SSS, a reference signal RS, and data to the UE, and receives data and channel feedback information from the UE.

The controller 1410 generates a signal for each type and maps the signal to a resource. For this, the controller 1410 may have a separate resource allocation unit 1411 or may perform a corresponding function as a part of the controller 1410.

The standard content or standard documents referred to in the above-mentioned embodiments constitute a part of this specification, for the sake of simplicity of description of the specification. Therefore, it is to be understood that the content of the above standard content and some of the standard documents is added to or contained in the scope of the present invention, as falling within the scope of the present invention.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (20)

A method for a terminal to receive a signal in a high-frequency mobile communication system,
Receiving a synchronization signal to which a beam is applied through a resource composed of subcarriers that are multiples of 15 kHz;
Confirming the beam identifier information and the cell identifier information included in the synchronization signal; And
And acquiring time-frequency synchronization based on the synchronization signal for which the beam identifier information is identified.
The method according to claim 1,
Further comprising receiving a beam reference signal to which the same beam as the synchronization signal is applied in the same frequency band as the frequency band in which the synchronization signal is received.
3. The method of claim 2,
Wherein the beam reference signal is received at a location other than a first symbol to a third symbol of a subframe.
3. The method of claim 2,
Wherein the beam reference signal is received in a subframe in which the synchronization signal is not received.
The method according to claim 1,
Wherein a minimum system bandwidth that can be operated in the high frequency mobile communication system is determined based on the number of resource blocks used for the synchronization signal and the interval of the synchronization signal when the synchronization signal for a plurality of beams is transmitted.
The method according to claim 1,
When the synchronization signal for a plurality of beams is transmitted, based on a time interval of the synchronization signal and a time required to transmit all synchronization signals for the plurality of beams, How the minimum time is determined.
A method for a base station to transmit a signal in a high-frequency mobile communication system,
Generating at least one synchronization signal including beam identifier information and cell identifier information;
Applying different beams to the one or more synchronization signals according to the beam identifier information; And
And distributing and transmitting the one or more synchronization signals to which the beam is applied, at different locations on a time-frequency basis.
8. The method of claim 7,
And transmitting a beam reference signal to which the same beam as the synchronization signal is applied, in the same frequency band as the frequency band in which the synchronization signal is transmitted.
9. The method of claim 8,
Wherein the beam reference signal is transmitted from a first symbol to a third symbol of a subframe.
9. The method of claim 8,
Wherein the beam reference signal is transmitted in a subframe in which the synchronization signal is not transmitted.
8. The method of claim 7,
Wherein a minimum system bandwidth that can be operated in the high frequency mobile communication system is determined based on the number of resource blocks used for the at least one synchronization signal and the interval of the synchronization signal.
8. The method of claim 7,
Wherein a minimum time required for the terminal to acquire synchronization of a particular cell is determined based on a time interval of the one or more synchronization signals and a time required to transmit both of the one or more synchronization signals.
A terminal for receiving a signal from a base station in a high-frequency mobile communication system,
A communication unit for receiving a synchronization signal to which a beam is applied through a resource composed of subcarriers that are multiples of 15 kHz from the base station; And
And a controller for checking the beam identifier information and the cell identifier information included in the synchronization signal and acquiring time-frequency synchronization based on the synchronization signal for which the beam identifier information is confirmed.
14. The method of claim 13,
Wherein,
And receiving the beam reference signal to which the same beam as the synchronization signal is applied in the same frequency band as the frequency band in which the synchronization signal is received.
15. The method of claim 14,
Wherein,
A terminal receiving the beam reference signal at a position other than a first symbol to a third symbol of a subframe.
15. The method of claim 14,
Wherein,
And receiving the beam reference signal in a subframe in which the synchronization signal is not received.
A base station for transmitting a signal to a terminal in a high-frequency mobile communication system,
Generating one or more synchronization signals including beam identifier information and cell identifier information, applying a different beam to the one or more synchronization signals according to the beam identifier information, and transmitting the one or more synchronization signals, A control unit for distributing the signals to different positions on the axis; And
And a communication unit for transmitting the at least one synchronization signal to which the beam is applied.
18. The method of claim 17,
Wherein,
And transmits a beam reference signal to which the same beam as the synchronization signal is applied, in the same frequency band as the frequency band in which the synchronization signal is transmitted.
19. The method of claim 18,
Wherein,
And transmits the beam reference signal at positions other than the first to third symbols of the subframe.
19. The method of claim 18,
Wherein,
Wherein the beam reference signal is transmitted in a subframe in which the synchronization signal is not transmitted.

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