KR20090065417A - A method of generating and transmitting data in mobile communication system - Google Patents

Abstract

A method of generating and transmitting data in a mobile communication system is provided to allocate sync information about system sync and cell search to at least one sub sync channel, thereby reducing complexity of a sync process. One multiple carrier symbol including at least two sub sync channels is generated. The generated multiple carrier symbol is transmitted to a receiving side through the sync channel. Each OFDM(Orthogonal Frequency Division Multiplexing) symbol is configured by at least two sub symbols.

Description

A method of generating and transmitting data in mobile communication system

The present invention relates to a data generation and transmission method in a mobile communication system, and more particularly, to a data generation and transmission method in a multi-carrier multiple access communication system.

는 직렬-병렬(Serial-To-Parallel) 변환부(100)를 거쳐 복수의 병렬 데이터 시퀀스(sequence)들로 만들어 진다. 일반적으로 직렬-병렬 변환부에서는 후속하는 역푸리에변환(Inverse Fast Fourier Transform;이하 IFFT)부(105)에서의 부반송파 변조부(110-0, 110-1,...,110-k)와 연동되어서 입력 데이터 시퀀스가 몇 개의 병렬 데이터 시퀀스들로 변환될 지가 결정된다. 이하의 설명에서는 직렬-병렬 변환부(100)에서 고속의 입력 데이터 시퀀스가 k개의 저속의 병렬 데이터 시퀀스들로 변환된다 가정한다.1 illustrates a process of generating a signal using multiple carriers in a transmitting side in the prior art. Referring to FIG. 1, an input data sequence consisting of N pieces of data

Is made of a plurality of parallel data sequences through a serial-to-parallel converter 100. In general, the serial-to-parallel transform unit is interworked with the subcarrier modulators 110-0, 110-1, ..., 110-k in the following Inverse Fast Fourier Transform (IFFT) unit 105. It is then determined how many parallel data sequences the input data sequence will be converted to. In the following description, it is assumed that the high-speed input data sequence is converted into k low-speed parallel data sequences in the serial-parallel converter 100.

The IFFT unit 105 carries a different subcarrier on each of the k low-speed parallel data sequences input to the IFFT unit 105 (ie, after subcarrier modulation), and subsequently performs parallel-to-serial conversion. The unit 110 is used to generate a serial IFFT transformed input data sequence. Thereafter, the IFFT-converted input data sequence is transmitted to the receiver through an RF (Radio frequency) unit 130. In the orthogonal frequency division multiplexing (OFDM) scheme, which is an example of a multicarrier transmission scheme, k subcarriers 110-0 and 110- are allocated to k parallel data sequences in the IFFT unit 105. 1,..., 110-k) are arranged to be orthogonal to each other on the frequency to be frequency-divided so that there is no interference between each subcarrier.

In general, an input data sequence in a digital communication system is composed of a combination of ones or zeros, and in the time domain, the input data sequence is a rectangular wave on / off. As is well known, a square wave is represented by the sum of frequency components of integer multiples when Fourier transform is performed. That is, the data representation in the time domain is represented by the data in the frequency domain. That is, any digital data may be represented in a time domain or in a frequency domain corresponding thereto. To describe this in more detail, a generation process of the multi-carrier signal of FIG. 1 will be described.

In the IFFT unit 120 of FIG. 1, each parallel data in terms of frequency domain is obtained by multiplying each parallel data sequence by subcarriers having different frequencies from each other corresponding to each parallel data sequence (subcarrier modulation process). The frequency of the sequence becomes higher by the frequency of the multiplied subcarrier. Each parallel data sequence modulated with subcarriers is then represented as an input data sequence in the time domain IFFT transformed via a parallel-serial unit 130.

Equation 2 shows an input data sequence passed through an IFFT having a size of N (N-size).

) 를 다중 반송파 심볼이라 칭한다. 이 다중 반송파 심볼에는 순환전치부(Cyclic prefix;이하 CP)가 삽입될수도 있다. CP는 다중 반송파 심볼의 앞부분에 그 다중 반송파 심볼의 뒷부분의 일정한 부분을 복사하여 붙이는 방식으로 형성되며, 다중 반송파 심볼의 주요 데이터가 수신측에 도착하기 전에 그 수신된 다중 반송파 심볼의 다중경로로 인한 영향을 없앤다. 다중 반송파 심볼에 CP를 부가하기 위해서 IFFT부(120)에 CP 부가부(도1에는 도시 안됨)가 추가될 수 있다. 참고로 다중 반송파 전송 방식의 일례인 OFDM 전송 방식이 사용된 경우 도 1의 각 부반송파들의 주파수는 주파수 영역에서 상호간에 직교하며, 부반송파로 변조된 각각의 병렬 데이터 시퀀스들도 주파수 영역에서는 상호 간에 직교하게 된다.In Equation 2, F ^{- 1} denotes an inverse Fourier transform matrix. This IFFT transformed input data sequence (

) Is called a multi-carrier symbol. A cyclic prefix (CP) may be inserted into this multicarrier symbol. The CP is formed by copying and pasting a certain part of the back of the multicarrier symbol at the front of the multicarrier symbol, and the multipath of the received multicarrier symbol due to the multipath of the received multicarrier symbol before the main data of the multicarrier symbol arrives at the receiver. Eliminate the impact A CP adder (not shown in FIG. 1) may be added to the IFFT unit 120 to add a CP to the multicarrier symbol. For reference, when the OFDM transmission scheme, which is an example of a multicarrier transmission scheme, is used, the frequencies of the respective subcarriers of FIG. 1 are orthogonal to each other in the frequency domain, and each parallel data sequence modulated by the subcarriers is orthogonal to each other in the frequency domain. do.

Next, a synchronization acquisition procedure of a terminal in a mobile communication system will be described. In a mobile communication system, a mobile station first receives a synchronization channel (SCH) and performs synchronization acquisition and cell search for smooth data transmission and reception with a base station using information contained in the synchronization channel.

A series of processes in which a terminal acquires synchronization from a base station and obtains a cell ID to which the terminal belongs is called a cell search. Cell search is an initial cell search performed when the terminal is initially powered on, and a neighbor cell search in which a terminal in a connection or idle mode searches for an adjacent base station. search). In general, in a mobile communication system, a system configuration is implemented on a cell basis. In order for a terminal of each specific location to access a mobile communication service, the terminal synchronizes with a base station that receives a signal having the strongest signal in terms of signal characteristics. Gain motivation). To this end, the base station transmits a signal for allowing the terminals in the base station to obtain synchronization through its synchronization channel to its own synchronization information. After the terminal synchronizes with the base station as described above, various control information can be obtained from the base station, and then corresponds to the base station using a means for synchronizing uplink synchronization, such as a random access channel (hereinafter referred to as RACH). Inform the presence of the terminal and attempts to make a call with the base station. More detail on the synchronization channel is as follows.

The synchronization channel is used for the terminal to acquire time synchronization and frequency synchronization with the base station at the beginning of the connection, and the terminal also acquires the cell ID and additional control information of the base station in accordance with the acquired and detected time synchronization and frequency synchronization. Used to enable acquisition. As such, the terminal acquires synchronization of time and frequency with the base station, cell ID of the base station, and additional control information related thereto through a synchronization channel. That is, the synchronization acquisition process of the terminal may be largely divided into the frequency synchronization, time synchronization and the cell ID acquisition process of the base station.

That is, the terminal performs a frequency offset estimation and compensation for time synchronization and frequency synchronization with the base station using the synchronization channel transmitted from the base station, and then obtains a cell ID of the base station. More specifically, the process of acquiring a cell ID may include performing a frame synchronization by searching a cyclic prefix CP of a transmission frame of a physical channel transmitting a sync channel in a blind manner and a cell group included in the sync channel. ID and cell ID, and if necessary, the antenna configuration included in the synchronization channel (antenna configuration detection) and DL frequency hopping indicator (DL frequency hopping indicatro), which is an example of the frequency configuration information The process may further include.

In addition, the UE may once again confirm the cell ID acquired in the previous step by using a reference signal such as a pilot signal of the downlink transmitted from the base station in order to secure a more reliable cell ID.

As described above, the synchronization acquisition of the terminal undergoes a multi-step acquisition process. For this purpose, the synchronization channel needs to be subdivided to fit each step. In particular, in the case of a mobile communication system using a multi-carrier, it is necessary to allocate the subdivided sync channel to a minimum radio resource region in view of the processing of a multi-carrier symbol unit.

An object of the present invention has been proposed to meet the above necessity in the prior art, and an object of the present invention is to provide a data generating method having a high transmission efficiency in a mobile communication system.

Another object of the present invention is to provide a method for generating a synchronization channel including one or more floating channel in a mobile communication system using multiple carriers.

The present invention proposes a method for generating a multicarrier symbol including two or more multicarrier subsymbols in a mobile communication system using a multicarrier transmission scheme. Multi-carrier subsymbol (hereinafter referred to as 'sub-symbol') is a kind of multi-carrier symbol in a mobile communication system using the multi-carrier transmission scheme proposed by the present invention and occupies less time domain or less frequency domain than conventional multi-carrier symbols. It means a multi-carrier symbol or a multi-carrier symbol that occupies the same time domain and frequency domain but is combined by a code division multiplexing scheme. Therefore, the conventional multi-carrier symbol may include two or more subsymbols proposed by the present invention.

To this end, two or more subsymbols may be multiplexed to be allocated to a radio resource region for one multicarrier symbol. Multiplexing methods that combine two or more subsymbols include time division multiplexing (TDM), frequency division multiplexing (FDM), and code division multiplexing (CDM). It is possible.

The subsymbols proposed in the embodiments of the present invention are not limited by whether they are defined in any particular region of the time domain or the frequency domain. That is, a signal defined in the time domain and converted into a frequency domain, or a signal defined in the frequency domain and converted to a time domain, may also be regarded as a signal in the final defined domain. That is, in the process of generating a multi-carrier symbol as described with reference to FIG. 1, the input data sequence may be interpreted either in the time domain or in the frequency domain, and thus is not limited by which specific domain is defined.

In one aspect of the present invention, a method for transmitting a synchronization channel at a transmitting side in a wireless communication system using a multi-carrier according to the present invention is described. To this end, one multi-carrier symbol including two or more sub-synchronization channels is generated, and the generated multi-carrier symbol is transmitted to the receiver through the synchronization channel.

In another aspect of the present invention, a method for generating a multi-carrier symbol for a synchronization channel at a transmitting side in a wireless communication system using the multi-carrier is described. To this end, a subsymbol associated with a floater channel corresponding to each of two or more data sequences including synchronization information is generated, and the floater channel subsymbols are combined to generate one multicarrier symbol.

Advantageously, the floating channel provides one or more of information on acquisition of time and frequency synchronization, information on antenna configuration, information on frequency bandwidth configuration, and information on cell ID.

Preferably, the floating channel subsymbol is a subsymbol including synchronization and cell ID related information provided by the floating channel.

Preferably, the subsymbols are combined in a TDM scheme when generating one multi-carrier symbol.

Preferably, when generating the one multi-carrier symbol, the subsymbols are combined in an FDM scheme.

Preferably, the subsymbols are combined in a CDM scheme when generating one multicarrier symbol.

According to one embodiment of the present invention, the following effects can be obtained.

First, the complexity of the synchronization process can be reduced by assigning synchronization information for system synchronization and cell search to one or more floating channel.

Second, the at least one floating channel allocated with the synchronization information is efficiently allocated by assigning the at least one floating channel to radio resources for one multicarrier symbol of a mobile communication system using a multicarrier transmission scheme using various multiplexing schemes. By using the radio resources can increase the data transmission efficiency.

The construction, operation, and other features of the present invention will be readily understood by the embodiments of the present invention described with reference to the accompanying drawings. The detailed description, which will be given below with reference to the accompanying drawings, is intended to explain exemplary embodiments of the present invention and is not intended to represent the only embodiments in which the present invention may be practiced.

Embodiments proposed in the present invention described below are applicable to a multi-carrier multiple access system considering mobile mobility of a terminal, for example, a mobile communication system using OFDM (hereinafter, referred to as an OFDM mobile communication system). It is also applicable to MC (Multi carrier) -CDMA, SC (Single carrier) -FDMA, Walsh-Hadamard (WH) -FDMS, and Discrete Fourier Transform (DFT) spread OFDMA.

The present invention can also be applied to the IEEE 802.16e system and the IEEE 802.16m system, which are standard standards for OFDM mobile communication systems. [The related standard standards are IEEEStd 802.16e-2005 and http://www.ieee802.org/16/. published.html]. The invention is also applicable to other similar mobile communication systems, such as Evolved Universal Terrestrial Radio Access (E-UTRA), also called Long Term Evolution (LTE). In addition, the present invention may be applied to an IMT-A system such as LTE-A (Advanced). The present invention can also be used in a variety of communication systems, including ways of using single antennas and multiple antennas.

In general, communication systems are widely deployed to provide various communication services such as voice and packet data. This technique can be used for downlink or uplink. Downlink means communication from the base station to the terminal, uplink means communication from the terminal to the base station. A base station generally includes a network excluding a terminal in a communication system that includes not only a physical transmission end but also an upper layer as a fixed point for communicating with a terminal. Therefore, in the present invention, the network and the base station have the same meaning as symmetrical parts with the terminal. The terminal may be fixed or mobile.

FIG. 2 is a diagram illustrating an example of a method for generating a multicarrier symbol including two or more subsymbols combined by a TDM scheme proposed in an embodiment of the present invention. In the embodiment proposed in FIG. 2, at least two or more subsymbols are combined, that is, multiplexed, in a TDM scheme in a time domain allocated to one symbol. In this case, each subsymbol may be configured to be immediately adjacent to each other on the time domain or may be configured to be separated from each other. The following is the definition of symbols to be used in this embodiment of multiplexing a subsymbol by the TDM scheme.

Tu: Length of a multicarrier symbol carried on a control channel or a data channel in a conventional mobile communication system using a multicarrier.

Tcp: Length of a cyclic prefix unit (CP) for a multicarrier symbol carried on a control channel or a data channel in a conventional mobile communication system using a multicarrier

Nsub: number of subsymbols to be multiplexed in one multicarrier symbol

Tu _n : Duration of nth subsymbol included in one multicarrier symbol, Tu _n ≥ 0.

Tcp _n : Length of CP of nth subsymbol included in one multicarrier symbol, Tcp _n n ≥ 0.

Two methods are available for multiplexing one or more subsymbols in a symbol using the TDM method.

1) TDM method 1

The sum of the durations of the subsymbols corresponds to the sum of the durations of the conventional general multicarrier symbol and the CP and corresponds to Equation 2. Here, the conventional general multi-carrier symbol means a conventional multi-carrier symbol for transmitting control information or data, not a symbol including multiplexed subsymbols as in the present invention.

2) TDM method 2

The sum of the durations of the subsymbols corresponds to the sum of the durations of the conventional general multicarrier symbols and corresponds to Equation 3.

2 is a diagram illustrating an example of a method for generating a multi-carrier symbol to which the TDM scheme 1 is applied, among the methods for generating a multi-carrier symbol specifically proposed in an embodiment of the present invention. Several subsymbols are multiplexed in a TDM scheme in one multicarrier symbol, and the sum of the total durations of the subsymbols including the CP coincides with the length of the multicarrier symbol for general data or control symbols.

The symbol duration Tu _n of the n th subsymbol of Equation 2 or Equation 3 or the CP duration Tcp _n of the n th subsymbol may all have the same value, or may have different values.

In addition, each subsymbol is not necessarily a symbol for the same information, but may be a subsymbol that plays a different role for each subsymbol. That is, some subsymbols may be carried on a broadcast channel, a data channel, or a control channel including a synchronization channel.

The CP part can also be filled with zeros to use as a guard time. Alternatively, one of each subsymbol following the CP may be selected to copy a specific portion of the subsymbol.

In addition, the rear part of each subsymbol may be used by copying forward.

3 is a diagram illustrating another example of a method for generating a multicarrier symbol using the TDM scheme 1 in the method for generating a multicarrier symbol proposed in an embodiment of the present invention. As shown in FIG. 3, unlike the case of FIG. 2, each subsymbol is adjacent to each other without a CP. There is only one CP at the beginning of the combined subsymbols. This CP was generated by copying a specific portion of the last subsymbol in FIG. 3 (the last portion in FIG. 3). Alternatively, as shown in FIG. 2, all CPs are nulled or a specific part of another subsymbol. You may. Alternatively, as shown in FIG. 4, the last specific portion of the first subsymbol may be allocated to CP.

FIG. 4 is a diagram illustrating another example in which the TDM scheme 1 is applied to a multicarrier symbol generation method proposed in another embodiment of the present invention.

FIG. 5 is a diagram illustrating an example of a method for generating a multicarrier symbol using the TDM scheme 2 in the method for generating a multicarrier symbol proposed in another embodiment of the present invention. As shown in FIG. 5, several subsymbols are combined in the form of TDM, and the total duration of the subsymbols including the CP assigned to each subsymbol (in the case of FIG. 5, copying the last part of the corresponding subsymbol). The length corresponding to the sum is equal to the length of the conventional general multicarrier symbol described above. The content and length of the CP, the length of the subsymbol, and the information to be conveyed are the same as in the embodiment of FIG.

FIG. 6 is a diagram illustrating another example of a method for generating a multicarrier symbol using the TDM scheme 2 in the method for generating a multicarrier symbol proposed in another embodiment of the present invention. As shown in FIG. 6, each subchannel is adjacent to each other without a CP. There is only one CP at the beginning of the subchannel combined by the TDM scheme, and this CP is a CP copied from the (Nsub-1) th subsymbol, which is the last subsymbol. Of course, the subsymbols to be copied by the CP need not be fixed to the subsymbols at any particular position and can be changed. In FIG. 7, unlike the case of FIG. 6, the CP is copied from the last specific portion of the first subsymbol.

FIG. 7 is a diagram illustrating another example of a method for generating a multicarrier symbol using the TDM scheme 2 in the method for generating a multicarrier symbol proposed in another embodiment of the present invention.

FIG. 8 is a diagram illustrating an example of a method for generating a multicarrier symbol using FDM among the methods for generating a multicarrier symbol proposed in another embodiment of the present invention. In another embodiment of the present invention, at least two or more subsymbols are proposed in the FDM scheme in the frequency domain allocated to one symbol.

8 to 12 are embodiments of the FDM scheme. The term "subsymbol" described above is mainly coincident with the viewpoint of the time axis domain, and is referred to as "subchannel" for the application of the present invention from the viewpoint of the frequency axis. Replace it.

 In this case, each subchannel may be configured to be immediately adjacent to each other on the frequency band or may be configured apart from each other. The frequency band to which each subchannel is allocated may be allocated by a specific allocation rule. In the method of combining subchannels in the FDM scheme proposed in another embodiment of the present invention, the subchannels are allocated in a scaling factor scheme around the center frequency in the frequency band allocated to the symbol. The following is a definition of symbols to be used in the following embodiments.

α _n : scaling factor for the nth subchannel (0 ≦ α _n ≦ 1)

B _n : frequency bandwidth allocated to the nth subchannel

As shown in FIG. 8, the first subchannel is allocated to the intermediate frequency (DC carrier in FIG. 8) in the frequency band allocated to one multicarrier symbol, and the next subchannel is allocated one frequency section from the intermediate frequency to the left and right bands. Done. In this case, as shown in FIG. 8, one subchannel is divided into two parts by a scaling factor and allocated. The nth subsymbol is allocated a frequency band of B _n , except for the first subchannel, one subchannel is divided by the scaling factor from side to side around the center frequency. In the case of the embodiment of FIG. 8, subchannel 1 corresponding to the second subchannel is divided into left and right by subchannel 0 and a predetermined guard band around the center frequency.

As shown in FIG. 8, subchannel 1 is allocated a total of B ₁ frequencies, of which subchannel 1 on the left side of the center frequency is assigned (1-α ₁ ) B ₁ and the right side of the center frequency. Subchannel 1 is assigned a frequency of α ₁ B ₁ . Other subchannels are allocated in the same manner. As such, when FDM is allocated by subchannels in a scaling factor based on a center frequency, the UE moves between several base stations (especially when receiving services while moving between base stations of heterogeneous mobile communication systems). In case of receiving, the bandwidth for one symbol is variably allocated to each base station and system according to its operation, so that when the OFDM symbol is transmitted to the terminal, the terminal searches for a subchannel from a predetermined minimum frequency band based on the center frequency. Subsequently, the sub-channel can be searched by extending the frequency band by a predetermined unit to cope with the case where the frequency domain is variably allocated.

9 is a diagram illustrating a frequency band searching method of a terminal in an FDM scheme proposed in another embodiment of the present invention. As shown in FIG. 9, when a frequency band is allocated to each symbol (or even one system) by 5 MHz, 10 MHz, or 20 MHz in one symbol, the terminal first searches for a 5 MHz band 910 around the center frequency. If the frequency band needs to be extended and searched, 10MHz (920) and 20MHz (930) are gradually enlarged and searched around the center frequency. This enables the terminal to efficiently receive data, thereby increasing the power efficiency of the terminal. Meanwhile, although not shown in FIG. 8, several adjacent carriers, including a DC carrier corresponding to a center frequency, may be used as a guard band for DC offset protection.

FIG. 10 is a diagram illustrating another example of a method for generating a multicarrier symbol using FDM proposed in another embodiment of the present invention. As shown in FIG. 10, in the present embodiment, except for subchannel 0, the remaining subchannels exist only on one of the left and right centers of the center frequency. As shown in FIG. 10, the odd subchannel (eg, subchannel 1) is located only to the right of the center frequency, and the even subchannel (eg, subchannel 2) is located only to the left of the center frequency. This location assignment can be reversed.

FIG. 11 is a diagram illustrating another example of a method for generating a multicarrier symbol using FDM proposed in another embodiment of the present invention. As shown in FIG. 11, in the present embodiment, even subchannels including subchannel 0 are allocated to the right of the center frequency and odd subchannels are allocated to the left of the center frequency. The location assignment of such a subchannel can be reversed. Subchannel 0 and subchannel 1 shown in FIG. 11 may or may not be distinguished by only one DC carrier or two or more DC carriers.

FIG. 12 is a diagram illustrating another example of a method for generating a multicarrier symbol using FDM proposed in another embodiment of the present invention. This embodiment is similar to the case of FIG. 8, but only with guard bands between subchannels. There is no difference in this. At this time, there may or may not be a DC carrier corresponding to the center frequency, which is determined by the system operating situation.

FIG. 13 is a diagram illustrating an example of a method for generating a multicarrier symbol using a CDM proposed in another embodiment of the present invention. In the embodiment shown in FIG. 13, two or more subsymbols are multiplexed in the CDM scheme in the time domain allocated to one symbol. At this time, each subsymbol is assigned a sequence defined in the time domain, and the sequences are multiplexed by the CDM method.

13 to 19 are embodiments in the CDM scheme. The term "subsymbol" described above is mainly coincident with the viewpoint of the time domain of the TDM scheme, and is referred to as a subchannel for the application of the present invention in the CDM scheme. Replace with the term.

There is no limitation on the type of sequence in the following embodiments. For example, a sequence such as a random sequence, a PN code, a Golay sequence, a CAZAC series sequence (Zadoff-Chu, modulated Frank, GCL, etc.) may be used.

As shown in FIG. 13, a multicarrier symbol is generated by a CDM method in which subchannels are added to each other at the same power ratio. This embodiment is applicable to the case where CP is added to each subsymbol or when CP is not added. In addition, each subchannel may be allocated at a different power ratio according to importance. This may be implemented by repeatedly generating important subchannels. The following embodiments shown in FIGS. 14 and 15 are embodiments for such a case.

FIG. 14 is a diagram illustrating another example of a method for generating a multicarrier symbol using a CDM proposed in another embodiment of the present invention. As shown in FIG. 14, in the time domain, CDM is repeated twice in one multicarrier symbol interval, and subchannel 1 is repeated three times. Subchannels may be masked with PN code chips to implement repetition in a certain period. Through repeated assignment of subchannels, a multicarrier symbol may be generated by reflecting a difference in importance between subchannels.

FIG. 15 is a diagram illustrating another example of a method for generating a multicarrier symbol using a CDM proposed in another embodiment of the present invention. 15 illustrates a case where CDM and TDM are simultaneously applied. Subchannel 0 is repeated twice, and subchannel 1 to subchannel 3 are combined by TDM and they are combined by CDM. As such, multi-carrier symbols can be generated by reflecting the importance of the subchannel and the amount of available resources according to the operation of the system.

FIG. 16 is a diagram illustrating another example of a method for generating a multicarrier symbol using a CDM proposed in another embodiment of the present invention. The previous CDM scheme constructs a multicarrier symbol by sub-channels sum of element-by-elements, but in the following embodiments, multi-carrier symbols are constructed by multiplying element-to-element between subchannels. It is defined as scrambling a product of an element versus an element between such subchannels. Scrambling in the following embodiments can be performed in the time domain and the frequency domain. In addition, as shown in FIG. 14 to FIG. 15, a method of allocating different power ratios between subsymbols or simultaneously applying the TDM is possible. Hereinafter, the following embodiments show such a case.

FIG. 17 is a diagram illustrating another example of a method for generating a multicarrier symbol using a CDM proposed in another embodiment of the present invention. As shown in FIG. 17, scrambling may be performed by configuring different power ratios between subchannels according to their importance.

FIG. 18 is a diagram illustrating another example of a method for generating a multicarrier symbol using a CDM proposed in another embodiment of the present invention. As shown in FIG. 18, the subchannels may be configured with different power ratios according to their importance, and the scrambling may be performed by using a TDM scheme.

FIG. 19 is a diagram illustrating another example of a method of generating a multicarrier symbol using a CDM proposed in another embodiment of the present invention. In FIG. 19, unlike in FIGS. 16 to 18, scrambling is performed between subchannels in a frequency domain rather than a time domain. In this case, application of the same method as in FIGS. 17 and 18 is also possible.

가 단편화(segmentation)부(210)에 입력된다. 단편화부(210)에서는 소정의 단위로 입력 데이터 시퀀스를 시스템에 의해 결정되는 t개의 데이터 블록으로 단편화를 한다. 또는 위의 경우와 달리 처음부터 입력 데이터 시퀀스가 복수의 단편화된 입력 데이터 시퀀스들일 수 있다. 이 경우는 단편화부는 필요없게 되나 본 실시예에서는 입력 데이터 시퀀스를 단편화하는 단편화부가 있는 경우를 가정한다.20 illustrates a method of generating a multicarrier symbol including subsymbols proposed in another embodiment of the present invention. First input data sequence

Is input to the segmentation unit 210. The fragmentation unit 210 fragments the input data sequence into t data blocks determined by the system in predetermined units. Alternatively, unlike the above case, the input data sequence may be a plurality of fragmented input data sequences from the beginning. In this case, the fragmentation unit is not necessary, but in the present embodiment, it is assumed that there is a fragmentation unit that fragments the input data sequence.

 Each of these fragmented data blocks is input to respective subsymbol generators 220-1, 220-2, ..., 220-t. The subsymbol generator includes a parallel-serial converter and an IFFT unit as in the multi-carrier symbol generator shown in FIG. 1. Each subsymbol generated by the subsymbol generator is input to the combiner 230 to generate one multicarrier symbol. Also, each subsymbol generator generates a plurality of subsymbols for each generated subsymbol if necessary. Add anterior part. The combiner 230 multiplexes the input subsymbols according to the embodiments of the present invention proposed in FIGS. 2 to 19. One multi-carrier symbol generated by the combiner 230 is transmitted on the radio channel via the RF unit 240.

 Next, the exemplary embodiments of FIGS. 2 to 19 are applied to the generation of a synchronization channel in a mobile communication system using a multicarrier.

As described above, the process of acquiring synchronization with the base station by the terminal may be divided into frequency and time synchronization and cell ID acquisition of the base station. It is not efficient in terms of complexity and radio resource management that the base station and the terminal perform all of these processes in one synchronization channel. The process is performed in a plurality of steps for the synchronization acquisition process and the control information necessary for each step is allocated to the subsymbol. Do it.

For this purpose, one or more sub-sync channels constituting the synchronization channel are defined. This floating channel is a channel for transmitting a subsymbol containing synchronization related control information.

In an example of allocating sync-related control information to be transmitted by applying an embodiment of the present invention, any floating channel x corresponds to a subsymbol to which cell ID information is assigned, and another floating channel y is a cell group. The case where ID information corresponds to the assigned subsymbol is mentioned. In this case, the terminal first obtains cell ID information of the current base station from the floating channel x, and obtains cell group ID information (or partial cell ID information) through the floating channel y. Using these two informations, the UE can structurally obtain cell ID information and cell group ID information. For example, when three cell ID information is allocated to a subsymbol corresponding to the floating channel channel x, and 170 cell group ID information is assigned to the subsymbol corresponding to the floating channel channel y, the floating channel and the floating channel Through y, a total of 510 cell IDs (= 3 × 170) can be represented. In addition, the floating channel includes information on antenna configuration (information on the number of antennas used in a synchronous channel or other channels), bandwidth allocation information, CP configuration information, various modes, and MIMO operation information. The assigned subsymbols may correspond.

Referring again to the case of applying the present invention to the synchronization acquisition process, in the above-described plurality of steps in synchronization acquisition, the floating channel 0 corresponds to a subsymbol for time and frequency synchronization acquisition information, and the floating channel 1 Corresponds to a subsymbol for cell ID classification related information, floating channel 2 corresponds to a subsymbol for cell group ID related information, and floating channel 3 corresponds to a subsymbol for antenna configuration related information. Sync channel 4 may correspond to a subsymbol for bandwidth configuration related information. When the synchronization-related information is transmitted through the floating channel corresponding to each subsymbol using two or more subsymbols, the floating channel corresponding to each subsymbol as shown in FIGS. 2 to 19. By combining the TDM, FDM, and CDM scheme, one multicarrier symbol may be generated.

When the multi-carrier symbol generated as described above is transmitted to the receiver through a synchronization channel, time diversity, frequency diversity, and code diversity effects can be obtained in transmission. Differently, the synchronization channel may be transmitted. In addition, by assigning a guard interval (guard time, guard frequency band, etc.) and CP for each floating channel, multi-carrier symbol transmission can be performed under the influence of channel distortion due to interference and multipath. In addition, it is also possible to multiplex and simultaneously transmit the floating channel corresponding to the subsymbol corresponding to the system information or emergency message information and the floating channel corresponding to the subsymbol related to the synchronization information.

21 and 22 illustrate a method of generating a synchronization channel proposed in an embodiment of the present invention.

The embodiment of FIG. 21 relates to generating by using the method proposed in the embodiment of FIG. 2 in generating a synchronization channel using the aforementioned floating channel. More specifically, the present invention relates to a method of using two subsymbols having the same length.

As described above, the synchronization channel may include time and frequency synchronization acquisition related information, cell ID classification related information, cell group ID related information, antenna configuration related information, and frequency bandwidth configuration related information. The synchronization channel related information may be allocated to symbol 0 and subsymbol 1. For example, time and frequency synchronization acquisition related information may be allocated to subsymbol 0 and the remaining synchronization channel related information may be allocated to subsymbol 1.

The embodiment of FIG. 22 relates to generating by using the method proposed in the embodiment of FIG. 5 in generating a synchronization channel using the aforementioned floating channel. More specifically, the present invention relates to a method of using two subsymbols having the same length. A specific subsymbol allocation method may use the method proposed in the embodiment of FIG. 21.

The two subsymbols according to the embodiments of FIGS. 21 and 22 have the same length and include synchronization channel related information, but may have different lengths, and other information other than the synchronization channel related information (for example, broadcast Cast related information, data channel related information, etc.). Alternatively, the synchronization channel related information and the other information may be allocated to different subsymbols.

23 shows a method of transmitting a synchronization channel proposed in another embodiment of the present invention. 23 illustrates a method of allocating two or more floating channel for transmitting a synchronization channel according to the present invention in an IEEE 802.16m system.

FIG. 23 shows the position within a super-frame of a synchronization channel of IEEE 802.16m. As is known, the frame structure of IEEE 802.16m may be configured using four frames as one superframe and eight subframes as one frame. Each super frame may include control information called a super-frame header (SFH). However, this is only an example and the present invention is applicable to other sizes of superframe and subframe sizes.

Each sync channel in a frame may consist of one OFDM symbol, which is an example of a multicarrier scheme. Each OFDM symbol may consist of two or more subsymbols proposed in the embodiments of FIGS. 2 to 19 of the present invention, and each subsymbol may be assigned a floating channel in FIGS. 21 to 22.

In the IEEE 802.16m system, an OFDM symbol for initial synchronization and cell information or an additional synchronization-related OFDM symbol for synchronization and cell information at handover may be configured in a hierarchical structure in which every frame exists. It may also be transmitted in a non-hierarchical structure.

In addition, the present invention can be applied to enable interworking with the conventional IEEE 802.16e system. As is known, in the IEEE 802.16e system, synchronization related information is transmitted to a preamble and a synchronization channel is repeated on a time axis. When the present invention is applied to the IEEE 802.16m, a synchronization pattern appears on the time axis. The signal for the synchronization channel may be loaded at each specific position of the carrier. The sync channel is composed of two or more float channels, and the characteristics of each float channel have been described above with reference to FIGS. 21 through 22.

When the synchronization channels for each system are transmitted in a TDM manner for interworking with IEEE 802.16m and IEEE 802.163 systems, the IEEE 802.16m synchronization channel is different from that of IEEE 802.16e to avoid collision with the IEEE 802.16e preamble signal. It can be transmitted so as to have a repeating pattern postmarked with each other.

In the above detailed description, the process of performing communication between the transmitting side and the receiving side has been described mainly for the convenience of description of the present invention and its embodiments. have. The terminology used herein may be replaced with other terms having the same meaning. For example, a terminal may be replaced with a mobile station, mobile terminal, communication terminal, user equipment or device, and the like, and a base station may be replaced with terms such as a fixed station, a Node B (NB), an eNB, and the like.

It is apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential features of the present invention. Accordingly, the above detailed description should not be interpreted as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

1 illustrates a process of generating a signal using multiple carriers in a transmitting side in the prior art.

2 is a diagram illustrating an example of a method for generating a multi-carrier symbol including two or more subsymbols combined by a TDM scheme proposed in an embodiment of the present invention.

3 is a diagram illustrating another example of a method for generating a multicarrier symbol according to an embodiment of the present invention.

4 is a diagram illustrating another example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

5 is a diagram illustrating an example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

6 is a diagram illustrating another example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

7 is a diagram illustrating another example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

8 is a diagram illustrating an example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

9 illustrates a frequency band search method of a terminal in an FDM scheme according to another embodiment of the present invention.

10 is a diagram illustrating another example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

FIG. 11 is a diagram illustrating still another example of a method of generating a multicarrier symbol according to another embodiment of the present invention.

12 is a diagram illustrating still another example of a method of generating a multicarrier symbol according to another embodiment of the present invention.

13 is a diagram illustrating an example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

14 is a diagram illustrating another example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

FIG. 15 is a diagram illustrating another example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

16 is a diagram illustrating another example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

17 is a diagram illustrating another example of a method for generating a multicarrier symbol according to another embodiment of the present invention.

18 is a diagram illustrating still another example of a method of generating a multicarrier symbol according to another embodiment of the present invention.

19 is a diagram illustrating still another example of a method of generating a multicarrier symbol according to another embodiment of the present invention.

20 illustrates a method for generating a multicarrier symbol including subsymbols according to another embodiment of the present invention.

21 illustrates a method of generating a synchronization channel proposed in an embodiment of the present invention.

22 illustrates a method of generating a synchronization channel proposed in another embodiment of the present invention.

23 shows a method of transmitting a synchronization channel proposed in another embodiment of the present invention.

Claims (14)

In the method of transmitting a synchronization channel on the transmission side in a wireless communication system using a multi-carrier, Generating one multi-carrier symbol comprising two or more sub-synchronization channels; and And transmitting the generated multi-carrier symbol to a receiver through the sync channel. The method of claim 1, And the floating channel provides at least one of information on acquisition of time and frequency synchronization, information on antenna configuration, information on frequency bandwidth configuration, and information on cell ID. The method of claim 2, The generating of the multi-carrier symbol comprises combining the two or more floating channels in a time divisional multiplexing (TDM) scheme. The method of claim 3, wherein The length of the generated multi-carrier symbol is the same as the length of one multi-carrier symbol for data and control information in a wireless communication system using the multi-carrier. The method of claim 4, wherein One multi-carrier symbol for the data and control information, characterized in that it includes or does not include a cyclic prefix (CP). The method of claim 2, The generating of the multi-carrier symbol comprises combining the two or more floating channel in a frequency divisional multiplexing (FDM) scheme. The method of claim 6, And the floating channel is allocated to different frequency domains according to a scaling factor frequency allocation scheme. The method of claim 2, The generating of the multi-carrier symbol comprises combining the two or more floating channel in a code divisional multiplexing (CDM) scheme in which the power ratio between each floating channel is not constant. The method of claim 2, Generating one multi-carrier symbol, Code divisional multiplexing (CDM) combining by element-by-element multiplication between the two or more floating channel. A method for generating a multi-carrier symbol for a synchronization channel at a transmitting side in a wireless communication system using a multi-carrier, Generating a subsymbol associated with a floater channel corresponding to each of two or more data sequences containing synchronization information; and Generating one multicarrier symbol by combining subsymbols associated with the floating channel. The method of claim 10, The subsymbol includes or does not include a cyclic prefix unit. The method of claim 11, The generating of the multi-carrier symbol may include combining the subsymbols in a TDM scheme. The method of claim 11, The generating of the multi-carrier symbol may include combining the subsymbols in an FDM scheme. The method of claim 11, The generating of the multi-carrier symbol may include combining the subsymbols in a CDM scheme.

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