KR20160141159A - Narrow band supporting method for machine type communication - Google Patents

Abstract

The present invention relates to a method for setting a narrow band usable between a base station and an object communication terminal in order to support a object communication terminal supporting only a narrow band .

Description

[0001] The present invention relates to a narrow band supporting method for a communication terminal,

The present invention relates to a method for supporting a narrow band for an object communication terminal, and more particularly, to a method for supporting a narrow band for a object communication terminal, in which a base station communicates with a object communication terminal And a method for setting a band.

In recent years, M2M (Machine-to-Machine) communication, which enables the acquisition and transmission of necessary information anytime and anywhere by connecting all the objects around the network, As a major issue.

On the other hand, in the 3rd Generation Partnership Project (3GPP) which is a mobile communication standardization organization, a standardization work is underway under the name of MTC (Machine Type Communications).

3GPP refers to an entity that does not require the direct manipulation or intervention of a 'machine', and MTC defines it as a form of data communication involving one or more of these 'machines'. That is, the MTC can be defined in the form of data communications associated with one or more entities that do not necessarily require human intervention.

Meanwhile, research on frequency hopping has been continued to improve the transmission efficiency between the object communication terminal and the base station.

For example, Korean Unexamined Patent Publication No. 2002-0042784 has studied a method of increasing the data transmission rate of an object communication apparatus by using frequency hopping.

In this case, there is a disadvantage in that it can not adapt to the state of the wireless channel by using a preset hopping period and a hopping frequency interval.

Korean Patent Publication No. 2012-0042784 (Apr. 24, 2012)

It is an object of the present invention to provide a narrow band frequency hopping apparatus for a communication terminal which enhances reception performance of a communication terminal by using frequency hopping from a base station to a communication terminal.

The present invention provides a narrow band frequency hopping apparatus for a stuffing communication terminal that increases reception performance by repeatedly transmitting a downlink signal of a base station through a frequency hopping device and adapts to a radio channel to change a frequency hopping pattern to improve reception reliability. .

The narrowband frequency hopping apparatus of the object communication terminal according to the present invention includes a object communication terminal for receiving a downlink signal using frequency hopping at a base station.

Here, the frequency hopping includes a primary synchronization channel (PSS), a secondary synchronization channel (SSS), a physical control format indicator channel (PCFICH), a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH) , A PHICH (physical hybrid ARQ channel), and a PMCH (physical multicast channel).

It is further preferable that the frequency hopping is used in the same pattern within the cell radius serviced by the base station.

Here, it is more preferable that the frequency hopping is repeatedly used in a certain pattern.

Further, it is more preferable that frequency hopping is used in a random pattern within a certain length.

Here, it is more preferable that the frequency hopping is used in a pattern except for a specific frequency band.

It is further preferable that the frequency hopping is used in a pattern suitable for the channel state after the scanning is performed on the radio channel state between the base station and the object communication terminal.

It is more preferable that the frequency hopping is used in a variable pattern previously notified to the object communication terminal.

It is more preferable that the frequency hopping is used in accordance with the radio channel state between the base station and the object communication terminal in the frequency hopping candidate pattern.

It is more preferable that the frequency hopping is used by varying the pattern according to the size of transmission data between the base station and the object communication terminal.

It is more preferable that the frequency hopping is used by varying the pattern according to the importance of transmission data between the base station and the object communication terminal.

It is more preferable that the object communication terminal does not use frequency hopping when the radio channel state between the base station and the object communication terminal is good.

Further, it is more preferable that the object communication terminal be designated to use and not to use frequency hopping from the base station.

Here, it is more preferable that the object communication terminal receives from the base station a frequency hopping downtime that does not use the frequency hopping for a certain period of time.

In addition, it is more preferable that the object communication terminal receives from the base station a dormant time between frequency hopping that is idle for a certain period of time between hopping of frequency hopping.

Here, it is more preferable that the object communication terminal receives a frequency hopping guard band, which is a frequency band not used for hopping between hopping bands of frequency hopping, from the base station.

Further, it is more preferable that the object communication terminal is fixedly or variably assigned a frequency hopping holding time from the base station for each frequency hopping.

Here, the object communication terminal uses time hopping simultaneously in frequency hopping or time hopping only without frequency hopping.

Also, the object communication terminal receives from the base station a narrow band or a usable narrow band including the minimum band in which the object communication terminal communicates with the base station in uplink and downlink signals.

Here, the object communication terminal communicates with the base station using at least narrow band that is aligned with the existing PRB mapping, and the narrow band includes at least one PRB and includes 6PRB.

Also, the object communication terminal receives at least PSS, SSS, PBCH within the system bandwidth without frequency hopping.

Here, the object communication terminal uses frequency hopping within the system bandwidth for at least one common message, at least for the cell extension, the response to RAR, paging, and MTC SIB (s).

Also, the object communication terminal supports narrowband frequency hopping and uses at least one of a sequential method, a random method, a limitation of the number of narrow bands, a hopping length, a hopping pattern length, a hopping pattern repeat number, And uses a hopping pattern.

The narrowband frequency hopping apparatus of the object communication terminal according to the present invention has an advantage of improving the reception performance of the object communication terminal by using frequency hopping from the base station to the object communication terminal.

Alternatively, the narrowband frequency hopping apparatus of the object communication terminal according to the present invention has an advantage of increasing the reception performance by improving the reception performance by repeatedly transmitting the downlink signal of the base station through the frequency hopping apparatus and changing the frequency hopping pattern by adapting to the wireless channel .

1 is a block diagram of a narrowband frequency hopping apparatus for a telecommunication terminal according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a frame structure in which the base station of FIG. 1 uses frequency hopping to a object communication terminal.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood that the present invention is not intended to be limited to the specific embodiments but includes all changes, equivalents, and alternatives included in the spirit and scope of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a narrowband frequency hopping apparatus for a telecommunication terminal according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a narrow band frequency hopping apparatus for an object communication terminal according to an embodiment of the present invention. FIG. 2 is a diagram for explaining FIG. 1 in detail.

Hereinafter, a narrowband frequency hopping apparatus for a telecommunication terminal according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG.

1, a narrowband frequency hopping apparatus for an object communication terminal according to an embodiment of the present invention includes a object communication terminal 200 that receives a downlink signal using a frequency hopping 400 in a base station 100, .

Here, the object communication terminal 200 is a mobile communication terminal connected to the base station 100, and is a terminal used for object communication in a mobile communication system.

That is, the object communication terminal 200 is configured as a low-cost terminal, and communicates with the base station 100 by supplementing the existing LTE (Long Term Evolution) standard in order to minimize power consumption and processing.

For example, since the object communication terminal 200 can be located far away from the base station 100 and can be used with low power, it is necessary to increase the reception gain of the object communication terminal 200.

The base station 100 may repeatedly transmit the same data to the object communication terminal 200 or increase the reception gain of the object communication terminal 200 using the frequency hopping 400. [

FIG. 2 is a diagram illustrating a frame structure in which the base station 100 of FIG. 1 uses a frequency hopping 400 to the object communication terminal 200. The frequency hopping 400 includes a primary synchronization channel (PSS), a secondary synchronization channel (SSS), a physical control format indicator channel (PCFICH), a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH) a shared channel, a PHICH (physical hybrid ARQ channel), and a PMCH (physical multicast channel).

Also, the frequency hopping 400 is used in the same pattern within the cell radius serviced by the base station 100.

Here, the frequency hopping 400 is characterized in that a predetermined pattern is repeatedly used.

Also, the frequency hopping 400 is characterized by being used in a random pattern within a certain length.

That is, the object communication terminal 200 can use a simplified structure to minimize processing and reduce power consumption.

First, when the frequency hopping pattern is fixed, since it does not receive the real-time notification of the hopping pattern to be processed when the frequency hopping 400 is changed, it is possible to reduce the wireless channel waste between the base station 100 and the object communication terminal 200 .

In addition, when the same frequency hopping pattern is used in the cell, the base station 100 can reduce processing required for frequency hopping (400) scheduling, and the object communication terminal (200) There is an effect that a collision with the other terminal with respect to the hopping 400 can be prevented in advance.

On the other hand, the object communication terminal 200 receives a frequency hopping repeating cycle 360 in which the frequency hopping repeating cycle 360 is repeated one by one, It is advantageous in that wireless channel waste can be reduced.

The frequency hopping pattern in which the frequency hopping 400 hopping between frequency bands is used to uniformly use the frequency band used for the frequency hopping 400 using the random pattern within the frequency hopping repeat period 360 having the designated length .

The frequency hopping 400 can maintain a frequency hopping use frequency band 330 composed of 1 physical resource block (PBR) to 6 PRB as a bandwidth and a frequency hopping hold time 310 composed of at least one subframe.

Meanwhile, the frequency hopping retention time 310 may be changed every time, and between the frequency hopping 400 and the frequency hopping dwell time 320 and the frequency hopping guard band 340 may be used. Also, the frequency hopping repetition period 360 may be repeated one cycle at a time, and may be stopped by the frequency hopping pause time 370 before it is repeated.

The frequency hopping 400 according to another embodiment is used in a pattern except for a specific frequency band.

The frequency hopping 400 may be used in a pattern suitable for the channel state after the scanning of the radio channel state between the base station 100 and the object communication terminal 200 is performed.

That is, the radio channel environment between the base station 100 and the object communication terminal 200 may not consider the mobility of the object communication terminal 200, so that the radio channel environment characteristic may not change rapidly. Therefore, if the quality of a specific frequency band is not good, the quality is not good. Therefore, a frequency band where a lot of errors occur can be avoided and used.

Meanwhile, the object communication terminal 200 can use a frequency hopping pattern for hopping only a good frequency band after the scanning of the radio channel state between the base station 100 and the object communication terminal 200 is performed .

The frequency hopping 400 according to another embodiment is characterized in that it is used in a variable pattern previously notified to the object communication terminal 200. [

In addition, the frequency hopping 400 is characterized in that any one of the candidate patterns of the frequency hopping 400 is designated according to a radio channel state between the base station 100 and the object communication terminal 200.

Here, the frequency hopping 400 is characterized in that the pattern is varied according to the size of transmission data between the base station 100 and the object communication terminal 200.

In addition, the frequency hopping 400 is characterized in that the pattern is varied according to the importance of transmission data between the base station 100 and the object communication terminal 200.

Here, the object communication terminal 200 does not use the frequency hopping 400 when the radio channel state between the base station 100 and the object communication terminal 200 is good.

Also, the object communication terminal 200 is characterized in that the use and nonuse of the frequency hopping 400 is designated from the base station 100.

That is, the object communication terminal 200 can use the wireless channel efficiently by using the frequency hopping 400 in a variable manner.

In the case of the object communication terminal 200, since it is difficult to transmit the frequency hopping pattern every time, the candidate group of the frequency hopping 400 can be designated and the number can be designated from at least two to sixteen.

A suitable radio channel candidate group can be used according to the radio channel condition. For example, when the radio channel state is poor due to interference by other terminals between the base station 100 and the object communication terminal 200, the frequency hopping 400 may be frequently used to increase the frequency hopping gain.

On the other hand, when the number of transmission data is large, the data transmission rate may be reduced in the embodiment requiring a pause time every frequency hopping 400, so that the frequency hopping 400 needs to be performed slowly.

On the other hand, when data having a high level of importance is transmitted, frequency hopping 400 can be frequently used in order to reduce reception errors for a specific frequency.

Lastly, when the channel state is good, the object communication terminal 200 may use only a fixed frequency band without using the frequency hopping 400, thereby minimizing the transmission speed degradation due to the frequency hopping 400. [

When the channel state is good or the object communication terminal 200 does not support the frequency hopping 400, the object communication terminal 200 transmits the used and unused information to the base station 100 so that the frequency hopping 400 is not used. Can be notified.

The object communication terminal 200 according to another embodiment of the present invention is characterized in that the base station 100 receives a frequency hopping pause time 370 in which the frequency hopping 400 is not used for a predetermined period of time.

In addition, the object communication terminal 200 is characterized in that the base station 100 receives a dormancy 320 between frequency hopping dormant for a certain period of time between hopping of the frequency hopping 400.

Herein, the object communication terminal 200 is characterized in that a frequency hopping guard band 340, which is a frequency band not used for hopping between hopping bands of the frequency hopping 400, is designated from the base station 100.

That is, the object communication terminal 200 can stably operate the object communication terminal 200 by setting the idle time without using the frequency hopping 400 at all times, and shortening the processing time.

For example, if the object communication terminal 200 can not perform the frequency hopping 400 or the base station 100 can not perform the frequency hopping 400 for another reason, the object communication terminal 200 may transmit The base station 100 may be informed of start time, end time, and reason for not performing the frequency hopping 400.

This idle time may be a frequency hopping dwell time 370 or a frequency hopping dwell time 320.

On the other hand, depending on the characteristics of the terminal, a frequency hopping guard band 340 indicating a dormant band other than a dormant time may be used.

That is, the frequency hopping guard band 340 can be used when the frequency hopping 400 is used and because of the structure problem of the transmission / reception filter of the object communication terminal 200, interference between the adjacent transmission and reception bands can be used, The inter guard band 340 may use at least one PRB.

The object communication terminal 200 according to another embodiment of the present invention is characterized in that a frequency hopping retention time 310 is fixedly or variably designated by the base station 100 for each frequency hopping 400.

That is, the same time may be used for each hopping in the frequency hopping 400, but a good frequency band may be hopped redundantly due to the characteristics of the wireless channel.

Therefore, although the minimum time of the frequency hopping 400 may be designated as one subframe, the subframe may be used without being designated separately.

The object communication terminal 200 according to another embodiment may use the time hopping simultaneously or only the time hopping without the frequency hopping 400 in the frequency hopping 400. [

That is, the gain of the time hopping can be obtained by the effect of obtaining the gain of the frequency hopping 400.

In case of the object communication terminal 200, reliable data transmission may be more important than processing in real time.

Accordingly, it is possible to use frequency hopping 400 and time hopping simultaneously or time hopping instead of frequency hopping 400. [

The object communication terminal 200 according to another embodiment of the present invention may transmit the size of the narrow band including the minimum band in which the object communication terminal 200 communicates with the base station 100 or the usable narrow band from the base station 100 .

Here, the object communication terminal 200 communicates with the base station 100 using at least a narrow band that is aligned with the existing PRB mapping, and the narrow band includes at least one PRB, and 6PRB may be used.

That is, the minimum band to be communicated by the base station 100 and the object communication terminal 200 can be defined as a narrow band and can also be defined by other methods. The minimum bandwidth may be 1PRB, which is the minimum bandwidth for communication in LTE, and the smallest data may use one subcarrier. Generally, six PRBs are used as a basis in consideration of the transmission capacity of the object communication terminal 200 .

However, depending on the application, it may be used in 2 to 5 PRBs when data is small, and may be used as a multiplier of 2 in order to freely express data.

However, although the object communication terminal 200 is as simple as on / off, since the data capacity such as image transmission is large, the narrowband definition can be used up to half of the system bandwidth.

The object communication terminal 200 according to yet another embodiment can receive at least the PSS, the SSS, and the PBCH without frequency hopping 400 within the system bandwidth.

Here, the object communication terminal 200 can use the frequency hopping 400 within the system bandwidth for at least any one of the common messages, at least for the cell extension, the RAR, the paging, and the response to the MTC SIB (s) .

In the case of PSS, SSS, and PBCH, since the object communication terminal 200 is the first portion to receive, there is not enough time to recognize and perform the frequency hopping 400. Therefore, PSS, SSS, and PBCH may use a predefined frequency band without using frequency hopping (400).

Also, since the object communication terminal 200 needs to have high reception sensitivity in order to expand the cell, the common message RAR, paging, and MTC SIB (s) can be received using the frequency hopping 400.

The object communication terminal 200 according to another embodiment of the present invention supports a narrowband frequency hopping 400 and is configured to support an inter-narrowband frequency hopping 400 and to control the inter-band frequency hopping 400 according to an order method, a random method, A hopping pattern can be used by using at least one of narrow band positions.

That is, the hopping pattern can be used in various ways. Narrow bands such as 1, 2, 3, 4, and 5 can be designated sequentially or narrow bands by random occurrence formula such as CRC.

The length of the frequency hopping 400 capable of transmitting and receiving the repeated data in the hopping can be appropriately used according to the length in which the wireless environment can be slowly changed so that the hopping gain can be obtained and at least one of the 128 lengths can be prevented from exceeding have.

Also, it is possible to simplify the processing in the object communication terminal 200 so that the length of the hopping pattern is not sufficiently long, so that any value of 32 times or less the maximum number of narrow bands can be used.

The position of the initial narrow band may be defined and used. Alternatively, the initial narrow band position may be defined and used for each object communication terminal 200 according to the type of the object communication terminal 200.

The MTC uses a narrow band where the narrow band means a subcarrier unit in the minimum band used for transmission of information from the object communication terminal 200 to the base station 100 or the base station 100 to the object communication terminal 200, Can be used in PRB units.

6PRB can be used as a base, but it can be used in units of 1, 2, 4 and 8PRB depending on the amount of data of MTC. It can be used as 6PRB or 5PRB in units of 6, 12, 18PRB or 6, It can also be used in multiples of 5 as shown in Fig.

When the basic unit such as 3PRB, 5PRB, 7PRB, and 9PRB is used as the number of holes, the center frequency can be used as a PRB positioned in the middle, which is advantageous in that modulation and demodulation are simple.

On the other hand, in case of 2PRB, 4PRB or 8PRB, center frequency is located between PRBs, which is inconvenient for modulation and demodulation, and 2PRB is used as the smallest unit, but data processing is advantageous.

The narrow band notification method may be transmitted by a channel through which the base station 100 transmits the base station information to the object communication terminal 200 or a channel that performs resource block allocation as well as notifying the frequency hopping information.

Since MTC uses narrow band, it can perform frequency hopping between subcarriers in a narrow band. However, in order to increase the frequency effect, frequency hopping can be performed in narrow band units.

The candidate band of frequency hopping may be adjacent to the first band, but non-adjacent bands may be used to increase the frequency hopping gain.

The PDSCH hopping can be performed only when the frequency hopping field of the PDSCH is set to enable. The frequency hopping field is a downlink information control channel or resource block allocation transmitted from the base station 100 to the object communication terminal 200 Lt; / RTI > channel.

Frequency hopping may be used between timeslots within one subframe or between subframes. It is also possible to use both the subframe and the subframe simultaneously.

The number of resource blocks used for hopping can be reported through the hopping offset related parameter of the PDSCH.

The base station may use a hopping pattern used in the PUSCH for frequency hopping, or may designate an arbitrary pattern of the base station.

For frequency hopping, information about subframes and timeslots of frequency hopping in which the first PDSCH will be located may be transmitted from the PDSCH resource allocation field.

If the hopping pattern is not separately specified, the currently set hopping pattern can be used.

The hopping pattern can be divided into a case where one subband is a hopping unit and a case where a plurality of subbands are used.

The object communication terminal can be made inexpensive. However, in order to make a terminal supporting all of the system bandwidth (for example, 10 MHz, 20 MHz, or 40 MHz) supported by one cell, the chip supporting the physical layer becomes high-priced and can be considerably expensive. Therefore, it is necessary to develop a device capable of supporting only a part of the system bandwidth in order to construct a low cost object communication terminal.

A narrow band for communication between the object communication terminal and the base station can be set.

Narrow bands can be defined as a set of consecutive physical resource blocks (PRBs).

In the case of the TDD transmission scheme, the narrow band should be set to be the same for uplink and downlink. In other words, they must be set to have the same set of subcarriers.

Narrow bands can use 5 or 6 PRBs.

In the case where the object communication terminal and the general terminal are mixed, the narrow band for the object communication terminal may be located at both ends of the system band in order to maximize the bandwidth of the general terminal.

To support multiple object communication terminals at the same time, a plurality of narrow bands can be set. If overlapping occurs between each narrowband station, the interference from the object communication terminal increases, and the terminal can be expensive to solve. Therefore, when a plurality of narrow bands are set to prevent this, the narrow bands should not overlap each other.

Narrow bands for object communication terminals may be defined as non-overlapping as a function of system bandwidth. As an example, the number of narrow bands available = system bandwidth / narrow bandwidth. Or the number of available narrow bands = (system bandwidth -k) / narrow bandwidth when k MHz bandwidth is always required for existing terminals.

The narrow band for the object communication terminal can be set so as not to overlap with each other with a certain number of PRBs starting with the lowest PRB index.

The narrow band for the object communication terminal can be defined in the logical layer rather than the physical layer.

A signaling signal is required to actively inform the object communication terminal of a narrow band for use by the object communication terminal, which causes waste of frequency resources. Therefore, in order to minimize waste of frequency resources due to signaling, a narrow band for the object communication terminal can be set to a fixed position in advance.

A plurality of narrow bands for the object communication terminal may be set in advance and different narrow bands may be allocated to each object communication terminal.

A plurality of narrow bands to be used may be set in advance, an index may be assigned to each narrow band, and an index may be used to indicate the position of the narrow band to be used by the object communication terminal.

Various methods for setting a narrow band that can be used by the object communication terminal and informing the object communication terminal of its position can be proposed. This method should be a method that maximizes the transmission rate while minimizing resource waste caused by signaling.

When the fixed position is used as the narrow band for the object communication terminal, the position can be informed in the following manner.

The SIB specific to the object communication terminal can be used to indicate the position of the narrow band to be used by the object communication terminal.

The MIB or SIB-1 may be used to indicate the location of the narrowband to be used by the object communication terminal.

It is necessary to actively notify the position of the narrow band when searching the frequency band having the best transmission efficiency and increasing the transmission rate by setting a narrow band in the frequency band. In this case, the position of the narrow band to be used by the object communication terminal DCI can be used to inform.

The position of the narrow band to be used by the object communication terminal can be informed in advance by using the upper message.

Also, among the predefined narrow bands, narrow bands used by a specific object communication terminal can be defined, and the prescribed narrow bands can be informed in advance using an upper message.

The base station can preset a plurality of narrow bands for the object communication terminal to overlap each other, but can allocate the narrow bands to be used by the object communication terminals at a specific moment so that they do not overlap each other.

In OFDM (Orthogonal Frequency Division Multiplexing), it is important to match the exact frequency and timing. Otherwise, a signal sent by another terminal may act as a noise. Such a frequency is adjusted using the center frequency, and as the frequency deviates from the center frequency, a minute difference becomes large and the noise becomes large. Therefore, in order to minimize noise, 72 subcarriers 410 (hereinafter, referred to as a center narrowband) existing in the center of the system excluding the DC component can be set as a downlink narrow band for the object communication terminal.

Among the entire subcarriers used in the system, nx72 (n is a natural number) adjacent subcarriers can be set to narrow band for object communication. In this case, n narrow bands can be set, and the narrow band (narrow band using the lowest frequency subcarrier) on the leftmost side can be set to the lowest narrow band, the narrow band on the far right side Narrowband used) can be defined as the highest narrowband.

If more narrowband than the already set narrowband is required, the band used by the general terminal can be borrowed to further set the narrowband for object communication.

FIG. 5 is a diagram showing the entire system band according to an embodiment of the present invention divided into a band 510 for narrow band for object communication and a band 520 for general terminal.

Referring to FIG. 5, the narrow band 511 using the subcarrier having the lowest frequency becomes the lowest narrow band and the narrow band 512 using the subcarrier having the highest frequency may be the highest narrowband.

If the band 510 for the narrow band is insufficient, the band for the narrow band can be increased by further using the band 520 for the normal terminal.

FIG. 6 is a diagram illustrating setting of a narrow band on the left and right around a center narrow band according to an embodiment of the present invention. Referring to FIG.

Referring to FIG. 6, NB0 at the center of the entire system band is a center narrow band, and two additional narrow bands NB1 611 and NB2 612 can be added using six PRBs to the left and right.

When a plurality of narrow bands are set, the positions of the PRBs for each narrow band are defined continuously, but the adjacent bands can be used based on the center narrow band.

It is not always necessary to symmetry with the center narrow band, and it can be set while expanding left and right with respect to the center before the PRB not defined as the narrow band. A plurality of narrow bands can be set starting from a PRB at a low frequency or starting from a PRB at a high frequency.

A plurality of narrow bands can be set starting from the left and right PRBs based on the center narrow band. The narrow band can be set in the form of a loop starting from the left side or the right side based on the center narrow band.

Since it is proper to use a center narrow band where noise can be minimized for transmitting a broadcast message for the object communication terminal, the PSS message, the SSS message and the PBCH message for the object communication terminal are transmitted using the center narrow band .

The PSS message, the SSS message, and the PBCH message may be transmitted using one or a plurality of narrow bands, but the PSS message, the SSS message, and the PBCH message may be independent regardless of the narrow band setting.

An offset can be set to allow the position of the uplink narrowband to be interlocked with the existing PUCCH and / or PRACH. The position of the uplink narrowband may then be determined by the existing PUCCH and / or PRACH + offset.

Since the center narrowband can also be used for data transmission, the center narrow band can also be used for frequency hopping in data transmission using frequency hopping.

PDCCH or PDSCH for object communication is the same as a broadcast signal that must be received by all the terminals, so it is proper to use a center narrow band which can minimize noise. Therefore, the center narrowband can be used for Physical Downlink Control Channel (PDCCH) or Physical Downlink Shared Channel (PDSCH) transmission for object communication.

In addition to the center narrow band, if the system bandwidth per cell is 3 MHz or more, it is possible to set a plurality of downward narrow bands that do not overlap each other.

However, in order to solve the shortage of the frequency band, when the system bandwidth is 3 MHz, the center narrow band and other narrow band may overlap.

The number of narrow bands that can be set can be determined based on the system bandwidth of the cell. The total bandwidth (the number of narrow bands X the bandwidth of one narrow band) used by the narrow band may be less than 1/2 of the system bandwidth.

As a result, some PRBs in the system may not be included in any set narrowband.

Some of the bands that are not used for MTC purposes can be separated from the narrowband for object communication.

In the case of the uplink narrow band, the base station can set the PRB (physical resource block) using the outermost frequency for narrow band use.

What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe all possible combinations of components or methods for purposes of describing the embodiments described, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the described embodiments are intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims.

Furthermore, to the extent that the term "comprising" is used in the detailed description or the claims, such term is intended to be embodied in a manner similar to that which is constructed as interpreted when used in a transitional word in the claims.

As described above, the narrowband frequency hopping apparatus of the object communication terminal according to the present invention is advantageous in that the reception performance of the object communication terminal is improved by using frequency hopping from the base station to the object communication terminal, and the downlink signal of the base station is transmitted through the frequency hopping apparatus It is advantageous to improve the reception performance by improving the reception performance by changing the frequency hopping pattern by adapting to the wireless channel.

Claims (23)

And an object communication terminal for receiving a downstream signal using frequency hopping at the base station. The method according to claim 1,
The frequency hopping includes a primary synchronization channel (PSS), a secondary synchronization channel (SSS), a physical control format indicator channel (PCFICH), a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH) a physical uplink shared channel (PUSCH), and a physical uplink control channel (PUCCH) in at least one of physical downlink shared channel (PHICH), physical hybrid ARQ channel (PHICH) And the narrowband frequency hopping device of the object communication terminal. The method according to claim 1,
Wherein the frequency hopping is used in the same pattern within a cell radius served by the base station. The method according to claim 1,
Wherein the frequency hopping is repeatedly used in a predetermined pattern. The method according to claim 1,
Wherein the frequency hopping is used in a random pattern within a predetermined length. The method according to claim 1,
Wherein the frequency hopping is used in a pattern except for a specific frequency band. The method according to claim 1,
Wherein the frequency hopping is used in a pattern suitable for the channel state after scanning the wireless channel state between the base station and the object communication terminal. The method according to claim 1,
Wherein the frequency hopping is used in a variable pattern previously notified to the object communication terminal. The method according to claim 1,
Wherein the frequency hopping is one of the candidate patterns of the frequency hopping according to a radio channel state between the base station and the object communication terminal. The method according to claim 1,
Wherein the frequency hopping is used by varying a pattern according to a size of transmission data between the base station and the object communication terminal. The method according to claim 1,
Wherein the frequency hopping is used by varying a pattern according to the importance of transmission data between the base station and the object communication terminal. The method according to claim 1,
Wherein the object communication terminal does not use the frequency hopping when the radio channel state between the base station and the object communication terminal is good. The method according to claim 1,
Wherein the object communication terminal is designated by the base station for use or nonuse of the frequency hopping. The method according to claim 1,
Wherein the object communication terminal receives a frequency hopping pause time not using the frequency hopping for a predetermined period of time from the base station. The method according to claim 1,
Wherein the object communication terminal is designated by the base station for a dormancy between frequency hopping that is idle for a certain period of time between hopping of the frequency hopping. The method according to claim 1,
Wherein the object communication terminal is provided with a frequency hopping guard band, which is a frequency band not used for hopping between the hopping bands of the frequency hopping, from the base station. The method according to claim 1,
Wherein the object communication terminal is fixedly or variably assigned a frequency hopping hold time for each frequency hopping from the base station. The method according to claim 1,
Wherein the object communication terminal simultaneously uses the time hopping in the frequency hopping or the time hopping only in the frequency hopping without using the frequency hopping. The method according to claim 1,
Characterized in that the object communication terminal receives from the base station a narrow band size or usable narrow band including the minimum band in which the object communication terminal communicates with the base station in upward and downward signals, Band frequency hopping device. The method according to claim 1,
Wherein the object communication terminal communicates with the base station using at least a narrow band that is aligned with the existing PRB mapping, the narrow band includes at least one PRB, and the 6PRB includes the narrow band Frequency hopping device. The method according to claim 1,
Wherein the object communication terminal receives at least PSS, SSS, and PBCH within the system bandwidth without the frequency hopping. The method according to claim 1,
Wherein said object communication terminal uses said frequency hopping within a system bandwidth for at least any one of a common message of RAR, paging, and a response to MTC SIB (s), at least in cell extension. A narrow band frequency hopping device of a terminal. The method according to claim 1,
The object communication terminal supports the frequency hopping between the narrow bands, and can perform at least one of an order method, a random method, a restriction of a narrow band number, a hopping length, a hopping pattern length, And the hopping pattern is used by using the hopping pattern.

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