KR101733759B1 - Apparatus and method for timing synchronization of communication system - Google Patents

Apparatus and method for timing synchronization of communication system Download PDF

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KR101733759B1
KR101733759B1 KR1020160027283A KR20160027283A KR101733759B1 KR 101733759 B1 KR101733759 B1 KR 101733759B1 KR 1020160027283 A KR1020160027283 A KR 1020160027283A KR 20160027283 A KR20160027283 A KR 20160027283A KR 101733759 B1 KR101733759 B1 KR 101733759B1
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interval
channel
response characteristic
symbol
differential component
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KR1020160027283A
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Korean (ko)
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윤영호
장은석
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주식회사 텔레칩스
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/0202—Channel estimation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/08—Modifications for reducing interference; Modifications for reducing effects due to line faults ; Receiver end arrangements for detecting or overcoming line faults
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/38—Synchronous or start-stop systems, e.g. for Baudot code
    • H04L25/40—Transmitting circuits; Receiving circuits
    • H04L25/49—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems
    • H04L25/4902—Pulse width modulation; Pulse position modulation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2626—Arrangements specific to the transmitter only
    • H04L27/2627—Modulators
    • H04L27/2634—Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation
    • H04L27/2636—Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]

Abstract

In a communication system, a symbol interval setting unit estimates a channel response characteristic candidate interval based on a received signal and a training symbol stored in advance in order to set a symbol interval of the signal. Estimates the channel differential component in the estimated channel response characteristic candidate interval, and estimates the effective channel response characteristic interval in the channel response characteristic candidate interval using the estimated channel differential component. The symbol interval is set so that the effective channel response characteristic interval is included in the valid symbol interval of the received signal.

Description

[0001] Apparatus and method for setting a symbol interval in a communication system [

The present invention relates to an apparatus and method for setting a symbol interval in a communication system.

OFDM (Orthogonal Frequency Division Multiplexing) system is known between the transceivers and performs time synchronization using a continuous training symbol. The OFDM system for transmitting the training symbols is 802.11a / g / n / ac system and CMMB (China Mobile Multimedia Broadcasting) system.

Conventionally, an impulse response of a channel is estimated by cross-correlation of received signals using training symbols known to each other between the transceivers. Or auto-correlation between consecutive training symbols to estimate the energy and perform time synchronization based on the energy.

A method of estimating a conventional channel impulse response will be described first with reference to FIG. 1 to FIG.

1 is a structural diagram of a general cross-correlation device.

As shown in FIG. 1, the channel impulse response characteristic estimating unit 12 estimates a channel impulse response characteristic for a received baseband signal using a training symbol stored in the training symbol storage unit 11 in advance. The Fast Fourier Transform (FFT) boundary controller 13 controls the Fast Fourier Transform boundary with the channel impulse response characteristic estimated by the channel impulse response characteristic estimator 12. [

The cross-correlation using training symbols using the cross-correlation apparatus will be described with reference to FIG.

Figure 2 shows cross-correlation using training symbols in general.

Referring to FIG. 2, a training symbol is cross-correlated with a received baseband signal. At this time, the training symbol (1) and the training symbol (2) are the same signal.

Here, before the point (a), there are many noises in the estimated impulse response due to the data symbol. Therefore, accurate impulse response characteristics can be estimated between points (a) and (b) without data symbols. However, since the punctual symbol (1) and the data symbol are correlated again from the point (b), the noise increases again.

When the actual channel has the profile shown in the following Table 1, the estimated channel characteristic is as shown in FIG. At this time, it is assumed that the number of samples of the data symbol and the training symbol is 2048.

1st 2nd 3rd 4th 5th Delay [sample] 0 256 370 500 1500 Atten [dB] 0 15 20 30 40

3 is a graph showing general estimated channel characteristics.

Referring to FIG. 3, the impulse response of the actual channel is estimated between points (c) and (d). (a) and (b) of FIG. 2 where the cross-correlation of the training symbols occurs between points (c) and (d)

On the other hand, before the point (c), only the noise characteristic exists due to the data symbol. Also, the channel impulse response characteristic is not revealed by the noise according to the data symbol from the point (d).

The first impulse response can not always be large due to various radio environments. That is, the first impulse response may be less than the following impulse response. If the magnitude of the first impulse response is much smaller than the second impulse response, the estimated channel characteristics are shown in Table 2 below.

1st 2nd 3rd 4th 5th Delay [sample] 0 256 370 500 1500 tten [dB] 40 0 20 30 40

If the first channel impulse response characteristic is smaller than the second channel impulse response characteristic, which is the next impulse response, the characteristic of the actual first channel is not displayed due to the noise due to the data symbol. This is the same as P1 in Fig.

On the other hand, the channel impulse response generated by the second training symbol can be estimated as the last channel, as shown in P3 in FIG.

Therefore, the actual channel is as shown in Table 2, but the estimated channel is estimated as shown in Table 3 below.

1st 2nd 3rd 4th 5th Delay [sample] 0 124 244 1244 1792 tten [dB] 0 20 30 40 40

Therefore, the FFT boundary can be controlled by the second channel impulse response, which may cause inter-symbol interference (hereinafter referred to as " ISI ") to be applied by the first channel, have.

Accordingly, the present invention provides an apparatus and method for setting a symbol interval in a communication system by estimating a channel impulse response using the same consecutive training symbols

According to another aspect of the present invention, there is provided a method for setting a symbol interval of a signal in a communication system,

Estimating a channel response characteristic candidate section based on a received signal and a previously stored training symbol; Estimating a channel differential component in the estimated channel response characteristic candidate interval; Estimating an effective channel response characteristic interval in the channel response characteristic candidate interval using the estimated channel differential component; And setting a symbol interval such that the estimated effective channel response characteristic interval is included in an effective symbol interval of the received signal.

The step of estimating the channel response characteristic candidate section may include: performing cross-correlation on the received signal using the training symbol; Adjusting a length of a first section and a length of a second section of the received signal in which the cross-correlation is performed; And estimating a channel response characteristic candidate section in the cross-correlated received signal.

The step of estimating the effective channel response characteristic interval may include estimating an interval greater than a predetermined reference value with respect to a maximum value of the channel response characteristic candidate interval as an effective channel response characteristic interval.

The step of estimating the effective channel response characteristic interval may include estimating an interval equal to or greater than a predetermined reference value with respect to the average value of the channel response characteristic candidate interval as an effective channel response characteristic interval.

Dividing the estimated channel differential component into a predetermined number of channels before estimating the effective channel response characteristic interval; And accumulating the segmented sections and obtaining the accumulated channel differential components.

The method may further include estimating an effective channel response characteristic interval in the channel response characteristic candidate interval using the estimated channel differential component and the accumulated channel differential component after the step of obtaining the accumulated channel differential component .

According to another aspect of the present invention, there is provided an apparatus for setting a symbol interval of a received signal in a communication system,

A channel impulse response characteristic estimating unit that performs a cross-correlation using the training symbols stored in advance in the received signal and estimates a channel response characteristic candidate interval in the received signal subjected to cross-correlation; A channel differential component estimator for estimating a channel differential component in the channel response characteristic candidate section; An effective channel estimator for estimating an effective channel response characteristic interval in a channel response characteristic candidate section using the estimated channel differential component; And a symbol interval controller for setting a symbol interval so that the estimated effective channel response characteristic interval is included in an effective symbol interval of the received signal.

The apparatus may comprise a training symbol storage for storing the training symbols known to the transmitter and the receiver.

The apparatus may further include a section dividing / accumulating unit for dividing the estimated channel differential component by a predetermined number of times, and accumulating the divided intervals to obtain accumulated channel differential components.

The effective channel estimator may estimate an effective channel response characteristic interval in a channel response characteristic candidate interval using the estimated channel differential component and the accumulated channel differential component.

According to the present invention, the actual channel impulse response can be estimated even if the channel impulse response does not decrease over time and becomes larger or smaller for a certain period of time.

Therefore, when the symbol interval is controlled, it is possible to determine the area where the ISI is minimum, thereby improving the signal reception performance.

1 is a structural diagram of a general cross-correlation device.
Figure 2 shows cross-correlation using training symbols in general.
3 is a graph showing general estimated channel characteristics.
4 is a structural diagram of a symbol interval setting apparatus according to the first embodiment of the present invention.
5 is a flowchart illustrating a symbol interval setting method according to the first embodiment of the present invention.
6 is an exemplary diagram illustrating an output of the channel impulse response characteristic estimating unit according to the first embodiment of the present invention.
7 is an exemplary diagram illustrating an output of the channel differential component estimator according to the first embodiment of the present invention.
8 is a structural diagram of a symbol interval setting apparatus according to a second embodiment of the present invention.
FIG. 9 is a diagram illustrating an output of the segmentation / accumulation unit according to the second embodiment of the present invention.
10 is a diagram illustrating another example of the output of the segmentation / accumulation unit according to the second embodiment of the present invention.
11 is a flowchart illustrating a method of setting a symbol interval according to a second embodiment of the present invention.

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

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

Also, the terms of " part ", "... module" in the description mean units for processing at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. Like reference numerals in the drawings denote like elements.

Hereinafter, an apparatus and method for setting a symbol interval in a communication system using continuous training symbols according to an embodiment of the present invention will be described in detail with reference to the drawings. The embodiment of the present invention will be described by taking two embodiments as an example according to the implementation of the symbol interval setting apparatus and the method of setting the symbol interval. In the embodiments of the present invention, OFDM systems among various communication systems will be described for convenience of explanation, but the present invention is not limited thereto.

4 is a structural diagram of a symbol interval setting apparatus according to the first embodiment of the present invention.

4, the symbol interval setting apparatus 100 includes a training symbol storage unit 101, a channel impulse response property estimating unit 103, a channel differential component estimating unit 105, an effective channel estimating unit 107, And a section control section 109.

The training symbol storage unit 101 stores training symbols that the transmitter and the receiver know each other. The training symbol is transmitted and stored from the transmitter. The manner in which the training symbol is transmitted and the type of the training symbol are already known, and a detailed description thereof will be omitted in the embodiment of the present invention.

Generally, in an OFDM system, a parallel signal is converted into a serial signal and transmitted. Therefore, in order to convert the received serial signal into a parallel signal on a symbol-by-symbol basis, the OFDM receiver needs symbol synchronization to capture the start point of the symbol.

When demodulating a received signal in an OFDM receiver, the start point of the signal must be captured. In order to accurately synchronize the carrier frequency and the oscillator frequency, the OFDM transmitter transmits a predetermined training symbol to the OFDM receiver. Accordingly, the training symbol storage unit 101 has a training symbol that the transmitter and the receiver know each other.

The channel impulse response characteristic estimation unit 103 receives a baseband signal as a reception signal. Then, the received signal is cross-correlated using the training symbol stored in the training symbol storage unit 101. To this end, the channel impulse response characteristic estimator 103 performs cross-correlation between the received signal and the training symbol using Equation (1).

Figure 112016022056488-pat00001

Where N denotes the number of samples of the training symbol and y [n] denotes the received signal. And p * [k] represents the training symbol. And k is an index for performing correlation in order to obtain an n-th sample value, which is a value corresponding to a preamble length of 0 to N-1, and N W is defined by the following equation (2).

Figure 112016022056488-pat00002

Here, N represents the training symbol length, which corresponds to the training symbol (1) in FIG. pre_margin (also referred to as a 'first section') refers to the length from the beginning of the training symbol to the beginning of the training symbol, that is, the length before the point of FIG. 2 (a). The post_margin (also referred to as a 'second section') means the length from the end of the training symbol to the end of the data symbol, that is, the length after the point of FIG. 2 (b) .

The channel impulse response characteristics estimating unit 103 adjusts the length of the first section and the second section length of the cross-correlated received signal to determine a channel response characteristic (hereinafter, referred to as "Quot; channel response characteristic candidate period "). By adjusting the length of the first interval pre_margin and the length of the second interval post_margin, the speed and efficiency of estimating the channel impulse response can be improved. At this time, the method of adjusting the two sections can be performed through various methods, so that the detailed description will be omitted in the embodiment of the present invention.

If the length of the first section and the length of the second section are set to N, which is the length of the training symbol, the output of the channel impulse response characteristics estimating section 103 is as shown in FIG. Referring to FIG. 6, the output of the channel impulse response characteristic estimating unit 103 will first be described.

6 is an exemplary diagram illustrating an output of the channel impulse response characteristic estimating unit according to the first embodiment of the present invention.

6 shows the power of the estimated impulse response, which is the output of the channel impulse response characteristic estimator 103, expressed as a log when pre_magin and post_margin are all set to N. [

4, the channel differential component estimator 105 estimates a channel differential component in a channel response characteristic candidate section estimated by the channel impulse response characteristic estimator 103. [ In order to estimate the channel differential component, the channel differential component estimator 105 uses the fact that the channel response characteristics due to successive training symbols are similar. Then, a channel differential component is estimated for data corresponding to the training symbol interval in the channel response characteristic candidate section. Here, the channel differential component is estimated using the following equation (3).

Figure 112016022056488-pat00003

In this case, Nx is defined as the sum of the training symbol length N and the length of the first section for obtaining the training symbol front part, and is expressed by Equation (4).

Figure 112016022056488-pat00004

The output of the channel differential component estimating unit 105 will first be described with reference to FIG.

7 is an exemplary diagram illustrating an output of the channel differential component estimator according to the first embodiment of the present invention.

2, if the first impulse response is smaller than the second impulse response, the channel impulse response estimator 103 does not show a channel impulse response corresponding to the applied channel. However, when the channel differential component estimator 105 estimates the channel differential component, it can be seen that a channel impulse response appears as shown in FIG.

4, the effective channel estimating unit 107 uses the channel differential component estimated by the channel differential component estimating unit 105 to calculate an effective channel response characteristic interval determined as a real channel in the channel response characteristic candidate interval . At this time, the following two methods can be used as the estimation method.

As a first method, a channel impulse response, that is, a channel response characteristic candidate interval, is estimated as an effective channel interval, which represents only a predetermined reference value or more with respect to a maximum value.

As a second method, there is a method of estimating an interval indicating only a certain reference value or more with respect to the total average value of the channel response characteristic candidate interval as an effective channel interval. The effective channel estimation unit 107 estimates an effective channel response characteristic interval through one of two methods.

Also, in the embodiment of the present invention, the effective channel is estimated by using the size of the channel differential component. However, the effective channel may be estimated using only the real part of the channel differential component. The method of using only the real part of the channel differential component will not be described in detail in the embodiment of the present invention.

The symbol interval control unit 109 sets a symbol interval so that the effective channel response characteristic interval estimated by the effective channel estimation unit 107 can be included in the effective symbol interval of the received signal. In the embodiment of the present invention, since the OFDM system is described as an example, the symbol interval controller 109 sets a Fast Fourier Transform (FFT) boundary to define an effective symbol interval. At this time, the method of setting the FFT boundary can be performed by various methods, so that detailed description is omitted in the embodiment of the present invention.

A method of setting a symbol interval using the symbol interval setting apparatus described above will be described with reference to FIG.

5 is a flowchart illustrating a symbol interval setting method according to the first embodiment of the present invention.

5, first, the channel impulse response characteristic estimation unit 103 receives a baseband signal transmitted from a transmitter (S100). Based on the training symbol stored in advance in the training symbol storage unit 101, And performs a cross-correlation with the received signal to estimate a channel response characteristic candidate section (S110).

If the channel response characteristic candidate section is estimated in step S110, the channel differential component estimating section 105 estimates the channel response characteristic candidate section by using training symbol intervals (S120). ≪ / RTI > If the channel differential component is estimated in step S120, the effective channel estimation unit 107 uses the channel differential component estimated by the channel differential component estimation unit 105 to calculate an effective channel estimated as a real channel in the channel response characteristic candidate period A response characteristic section is estimated (S130).

Finally, the symbol interval control unit 109 sets a symbol interval so that the effective channel response characteristic estimated by the effective channel estimation unit 107 can be included in the effective symbol interval of the received signal (S140).

Next, an apparatus and method for setting a symbol interval according to another embodiment of the present invention will be described.

8 is a structural diagram of a symbol interval setting apparatus according to a second embodiment of the present invention.

8, the symbol interval setting apparatus 100 'includes a training symbol storage unit 101', a channel impulse response characteristic estimator 103 ', a channel differential coefficient estimator 105' A symbol interval control unit 109 ', and a segmentation / accumulation unit 111, as shown in FIG.

The training symbol storage 101 'stores training symbols known to each other between a transmitter and a receiver.

The channel impulse response characteristic estimation unit 103 'receives the baseband signal as a received signal and performs cross-correlation on the received signal using training symbols stored in the training symbol storage unit 101'. Then, the length of the first interval and the length of the second interval are adjusted in the cross-correlated received signal to estimate a channel response characteristic candidate interval, which is an interval in which the channel response characteristic can be found.

The channel differential component estimator 105 'estimates the channel differential component in the channel response characteristic candidate interval estimated by the channel impulse response characteristic estimator 103' using the fact that the channel response characteristics due to the consecutive training symbols are similar to each other .

Here, the training symbol storage unit 101 ', the channel impulse response property estimating unit 103', and the channel differential component estimating unit 105 'are the same as those in the symbol interval setting unit 100 shown in FIG. Function.

The section division / accumulation unit 111 divides the channel differential component into sections in order to minimize the influence of the noise components in the channel differential components estimated by the channel differential component estimation unit 105 '. Then, the divided channel differential components are accumulated to obtain accumulated channel differential components. To divide and accumulate the channel differential components, the segmentation / accumulation unit 111 uses the following equation (5).

Figure 112016022056488-pat00005

In Equation (5), D is the number of samples to be included in each divided section, and K is obtained by dividing the entire channel differential component by Kx / D. And Diff r represents the conversion into the size or real component of the channel differential component. The method of obtaining the size of the channel differential component or the converted real component is already known, and a detailed description thereof will be omitted in the embodiment of the present invention.

This will first be described with reference to Figs. 9 and 10. Fig.

FIG. 9 is a diagram illustrating an output of an interval division / accumulation unit according to a second exemplary embodiment of the present invention, and FIG. 10 is another exemplary diagram illustrating an output of an interval division / accumulation unit according to the second exemplary embodiment of the present invention.

9, the characteristic (blue) of the magnitude component of the channel differential component and the output (red) of the segmentation / accumulation section are shown in FIG. As shown in FIG. 9, it can be seen that the output of the segmentation / accumulation unit is constant in the noise period in which no actual channel exists, while the size of the segment in which the channel exists is conspicuous.

Referring to FIG. 10, the characteristic (blue) of the real component of the channel differential component and the output (red) of the segmentation / accumulation portion are shown in FIG. As shown in FIG. 10, it can be seen that the characteristic of the noise period in which no actual channel exists is greatly changed as compared with FIG. When the real part of the channel differential component is used to divide and accumulate the segment, it is known that the cumulative value of the segment of the noise segment is significantly low. Therefore, when estimating the channel response, the probability of recognizing the noise as a signal is low .

8, the effective channel estimating unit 107 'compares the estimated channel differential component resulting from the channel differential component estimating unit 105' and the accumulated channel differential component, which is the result of the interval dividing / accumulating unit 111, And the effective channel is estimated using only the result of the segmentation / accumulation unit 111. [0157] Here, according to the method using the channel differential component and the effective channel estimation method, the effective channel can be estimated by various methods as follows.

When only the result of the segmentation / accumulation unit 111 is used in estimating the effective channel, the effective channel estimation unit 107 'estimates an effective channel using only a predetermined reference value or more with respect to the maximum value of the segmentation accumulation unit. Thus, there is an advantage that the cumulative value of the segmentation of the noise interval is almost similar, and the reference setting is easy.

If the effective channel is estimated using both the result of the segmentation / accumulation unit 111 and the result of the channel differential component estimation unit 105 ', not only the size ratio between the channel impulse responses can be used, There is an advantage that the reference setting is easy because the cumulative value of the section division is almost similar.

In the embodiment of the present invention, the effective channel is estimated using the size of the channel differential component. However, the effective channel may be estimated using only the real part of the channel differential component.

The symbol interval control unit 109 'sets a symbol interval so that the channel response characteristic estimated by the effective channel estimation unit 107' can be included in the valid symbol interval of the received signal. In the embodiment of the present invention, since the OFDM system is exemplified, the symbol interval controller 109 'sets an FFT boundary to set a symbol interval.

A method of setting a symbol interval using the symbol interval setting apparatus will be described with reference to FIG.

11 is a flowchart illustrating a method of setting a symbol interval according to a second embodiment of the present invention.

11, the channel impulse response characteristic estimating unit 103 'receives the baseband signal transmitted from the transmitter (S200), and transmits the training symbol stored in the training symbol storage unit 101' And estimates a channel response characteristic candidate interval (S210).

If the channel response characteristic candidate section is estimated in step S210, the channel differential component estimation section 105 'estimates the channel response characteristic candidate section by using the training symbol interval (S220). ≪ / RTI > In addition, the section division / accumulation unit 111 divides the channel differential component estimated by the channel differential component estimation unit 105 'and accumulates the divided channel differential component to minimize the influence of the noise component (S230) .

If the channel differential component is estimated in step S220 and the channel differential component is divided and accumulated in step S230, the effective channel estimator 107 'estimates the channel differential component estimated by the channel differential component estimator 105' In step S240, an effective channel response characteristic interval, which is determined to be a real channel, is estimated in a channel response characteristic candidate interval using the channel differential component divided and accumulated in the accumulator 111.

Finally, the symbol interval control unit 109 'sets a symbol interval so that the channel response characteristic estimated by the effective channel estimation unit 107' can be included in the effective symbol interval of the received signal (S250).

If the symbol interval is set using the symbol interval setting apparatus described above, the actual channel impulse response can be estimated even if the channel impulse response does not decrease with time and becomes larger or smaller during a certain period of time The signal reception performance is improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

Claims (13)

A method for setting a symbol interval of a signal in a communication system, the method comprising:
Performing cross-correlation using a training symbol previously stored in the received signal, and adjusting a length of the first section and a length of the second section of the cross-correlated received signal;
Estimating a channel response characteristic candidate section in a received signal in which cross correlation is performed;
Estimating a channel differential component in the estimated channel response characteristic candidate interval;
Estimating an effective channel response characteristic interval in the channel response characteristic candidate interval using the estimated channel differential component; And
Setting a symbol interval so that the estimated effective channel response characteristic interval is included in an effective symbol interval of the received signal
/ RTI >
delete The method according to claim 1,
The cross-
Figure 112017035880231-pat00006

Here, N denotes the length of the training symbol, y [n] denotes a baseband signal receiver, and, p * [k] represents the training symbol, N W is the length of the first section and a training symbol length The length of the second section
Lt; / RTI >
The first interval is a length from a data symbol start point to a training symbol start point, and the second interval is a length from a training symbol end point to a data symbol end point (Post-margin) In symbol interval. The method of claim 3,
Wherein estimating the channel differential component comprises:
Figure 112017035880231-pat00007

Where Nx is the sum of the training symbol length and the length of the first section
The symbol interval is estimated through the following equation. The method according to claim 1,
Wherein the estimating the effective channel response characteristic interval comprises:
And estimating a period longer than a preset reference value with respect to a maximum value of the channel response characteristic candidate interval as an effective channel response characteristic interval. The method according to claim 1,
Wherein the estimating the effective channel response characteristic interval comprises:
And estimating a period longer than a predetermined reference value with respect to the total average value of the channel response characteristic candidate intervals as an effective channel response characteristic interval. The method according to claim 1,
Prior to estimating the effective channel response characteristic interval,
Dividing the estimated channel differential component into a predetermined number of intervals; And
Accumulating the divided sections and obtaining the accumulated channel differential components
/ RTI > 8. The method of claim 7,
The accumulated channel differential component
Figure 112016022056488-pat00008

Where D is the number of samples in each interval, k is the number of all channel differential components segmented, Diffr is either a magnitude component of a channel differential component or a real component
To obtain a symbol interval. 8. The method of claim 7,
After the step of obtaining the accumulated channel differential component,
Estimating an effective channel response characteristic interval in the channel response characteristic candidate section using the estimated channel differential component and the accumulated channel differential component;
The symbol interval setting method further comprising: An apparatus for setting a symbol interval of a received signal in a communication system,
A channel impulse response characteristic estimating unit that performs a cross-correlation using the training symbols stored in advance in the received signal and estimates a channel response characteristic candidate interval in the received signal subjected to cross-correlation;
A channel differential component estimator for estimating a channel differential component in the channel response characteristic candidate section;
An effective channel estimator for estimating an effective channel response characteristic interval in a channel response characteristic candidate section using the estimated channel differential component;
A symbol interval controller for setting a symbol interval such that the estimated effective channel response characteristic interval is included in an effective symbol interval of the received signal; And
An interval dividing / accumulating unit for dividing the estimated channel differential component by a predetermined number, and accumulating divided intervals to obtain accumulated channel differential components;
And a symbol interval setting unit. 11. The method of claim 10,
A training symbol storage unit for storing the training symbols,
And a symbol interval setting unit. delete 12. The method of claim 11,
Wherein the effective channel estimator comprises:
And estimates an effective channel response characteristic interval in a channel response characteristic candidate section using the estimated channel differential component and the accumulated channel differential component.
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