JP2010225271A - Signal characteristics determination device, signal characteristics determination method, and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a signal characteristics determination method that determines characteristics of an RF signal more properly. <P>SOLUTION: A signal characteristics determination device includes: a binary data detection unit receiving a radio frequency (RF) signal, sampling the RF signal, and outputting binary data from the sampled RF signal; delay units 311-315 receiving the binary data and outputting the delayed binary data; a selection-signal generation unit 317 receiving the binary data and the delayed binary data output from each of the delay units to generate a selection signal; a channel identification unit 330 receiving the sampled RF signal and outputting the mean value of the sampled RF signal using the selection signal; and a signal-characteristics-determination-unit receiving the mean value of the sampled RF signal and determining a characteristic value showing the characteristics of the RF signal using the mean value of the received RF signal. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a signal characteristic determination method and apparatus and recording medium, and more particularly to a method and apparatus and recording medium for determining characteristics of an RF signal obtained from an optical disc.

  After converting the light reflected from the optical disk into an electrical signal, binary data recorded on the optical disk is reproduced through a predetermined signal processing process. At this time, a signal obtained by converting the light reflected from the optical disk into an electrical signal is referred to as an RF (Radio Frequency) signal. Even if a binary signal is recorded on the optical disk, the RF signal obtained from the optical disk has the characteristics of an analog signal due to the optical disk characteristics and optical characteristics. Binary data is obtained by binarizing the RF signal.

  According to the prior art, there are various indexes indicating the characteristics of the RF signal obtained from the optical disc. One example is asymmetry and modulation ratio. The RF signal includes signals having various periods depending on what code is used to modulate the data. For example, when modulation is performed using a (2, 10) code, a 3T (T is a unit period or pit length) signal that is three times the basic pit period becomes the shortest period signal, and an 11T signal becomes the maximum period signal. Asymmetry is a measure of how far the center of a signal having a predetermined period shorter than the maximum period is far from the center of the signal having the maximum period. The modulation degree is a measure indicating whether the magnitude of a signal having a predetermined period shorter than the maximum period is much smaller than the magnitude of the signal having the maximum period. FIG. 1 is a graph showing an eye-pattern signal for explaining asymmetry and modulation degree. The eye pattern signal is obtained by simultaneously displaying signals of various periods obtained from the optical disc on an oscilloscope.

  Referring to FIG. 1, 11TTOP and 11TBTM indicate the maximum value and the minimum value of an 11T signal that is a maximum periodic signal, respectively, when a modulation scheme is (2, 10) code. 3TTOP and 3TBTM respectively indicate the maximum value and the minimum value of the 3T signal that is the minimum periodic signal. The asymmetry and modulation degree of the RF signal are calculated using the 11TTOP, 11TBTM, 3TTOP and 3TBTM. A more detailed description of asymmetry and modulation depth is disclosed in US Pat. No. 5,490,127.

  In order for the data recording and / or reproducing apparatus loaded with the optical disc to reproduce the data recorded on the optical disc without error, the aforementioned asymmetry and the degree of modulation are required to have values in a predetermined range. Therefore, an accurate measurement of a measure indicative of RF signal characteristics such as asymmetry and modulation depth is important.

  However, as the recording density of the optical disc increases or the recording quality deteriorates, the quality of the RF signal obtained from the optical disc becomes progressively worse. Therefore, the scale indicating the characteristics of the RF signal such as asymmetry and modulation degree is accurately determined. There is a problem that it is difficult.

US Pat. No. 5,490,127

  Therefore, the technical problem to be solved by the present invention is to provide a signal characteristic determination method, apparatus and recording medium that can determine the characteristic of the RF signal more accurately.

  An aspect of the present invention for achieving the above object is an analog / digital converter that receives a radio frequency (RF) signal, samples the radio frequency (RF) signal, and outputs the sampled RF signal; A binary data detector for detecting binary data from the sampled RF signal and outputting the binary data; and a plurality of delay units for receiving the binary data and outputting the delayed binary data, respectively. Receiving the binary data and delayed binary data output from each of the plurality of delay units, generating a selection signal; and receiving the sampled radio frequency signal; A channel identification unit that outputs an average value of the sampled radio frequency signal according to a selection signal; and Receives the average value, by using the average value of the received radio frequency signal, the signal characteristics determination portion for determining a characteristic value indicating a characteristic of the radio frequency signal is to comprise a.

  Other features of the invention include sampling a radio frequency (RF) signal using an analog / digital converter, obtaining binary data from the sampled radio frequency signal, and using a plurality of delay units A step of delaying the binary data, and a step of generating a selection signal using the delayed binary data output from each of a plurality of delay units and the binary data obtained from the sampled radio frequency signal; Obtaining an average value of the sampled radio frequency signal according to the selection signal; and determining a characteristic value of the radio frequency signal using the average value of the sampled radio frequency signal. It is.

  According to still another aspect of the present invention, there is provided a computer-readable recording medium having recorded thereon a program for realizing a signal characterization method, wherein the method uses an analog / digital converter to convert a radio frequency (RF) signal. Sampling, obtaining binary data from the sampled radio frequency signal, delaying the binary data using a plurality of delay units, and a delay output from each of the plurality of delay units Generating a selection signal using binary data and binary data obtained from the sampled radio frequency signal; obtaining an average value of the sampled radio frequency signal by the selection signal; Using the average value of the sampled radio frequency signal, the radio frequency signal Determining a characteristic value, a readable recording medium having recorded a computer program for realizing the method comprising.

  According to still another aspect of the present invention, there is provided an analog / digital converter that samples a radio frequency signal at a predetermined period and outputs the sampled radio frequency signal in an apparatus for detecting binary data from a radio frequency (RF) signal. ADC), a sampled radio frequency signal output from the analog / digital converter, a DC offset canceller that cancels a DC offset value from the sampled radio frequency signal, and a system clock signal, A PLL for outputting a system clock signal to the analog / digital converter and the DC offset canceller, a plurality of delay units for receiving binary data and outputting delayed binary data, the binary data and the plurality of binary data From each delay A selection signal generation unit that receives the output delayed binary data and generates a selection signal; receives the sampled radio frequency signal; and averages the radio frequency signal sampled by the selection signal And a channel identification unit for outputting the average value of the sampled radio frequency signal, and using the received average value of the sampled radio frequency signal to indicate the characteristic of the radio frequency signal A signal characteristic determining unit, wherein the characteristic value indicates one of asymmetry, modulation ratio, and nonlinearity of the radio frequency signal; and the sampling output from the channel identification unit From the sampled radio frequency signal using an average value of the sampled radio frequency signal. A Viterbi decoder to obtain an advance data, and FIR filter for adjusting the channel characteristic of the signal input to the Viterbi decoder is to comprise a.

  According to the present invention, the predetermined characteristic value indicating the characteristic of the RF signal can be determined more accurately. In addition, the hardware implementation is further simplified, and the characteristics of the RF signal can be determined more accurately by using the output binary data of the Viterbi decoder.

It is a graph which shows an eye pattern (eye-pattern) signal. It is a figure which shows the block diagram of the signal characteristic determination apparatus by this invention. It is a figure which shows an example of the block diagram of the level detection part shown by FIG. It is a figure which shows an example of the block diagram of the signal characteristic determination part 500 shown by FIG. It is a figure which shows an example of the input-output signal of the signal characteristic determination part 500 at the time of using (1,7) code | cord | chord 5 tap. In the case of (1,7) code, it is a figure which shows the sampled RF signal. It is a figure which shows an example of the block diagram of the binary data detection apparatus containing the signal characteristic determination apparatus by this invention shown in FIG. It is a figure which shows other embodiment of the block diagram of the binary data detection apparatus provided with the signal characteristic determination apparatus by this invention shown in FIG.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 2 is a block diagram of a signal characteristic determination apparatus according to the present invention. Referring to FIG. 2, the signal characteristic determination apparatus according to the present invention includes a level detection unit 300 and a signal characteristic determination unit 500.

  The level detection unit 300 receives an RF signal obtained from an optical disc (not shown) and binary data obtained by binarizing the RF signal according to a predetermined method, and each level of the RF signal is obtained using the binary data. A selection signal for classifying the sample value by level is generated, and the sample value of the RF signal is classified by level using the selection signal, and then an average value of the sample values for each level is output.

  The signal characteristic determination unit 500 calculates a predetermined characteristic value indicating the characteristic of the RF signal using the average value of the sample values for each level of the RF signal output from the level detection unit 300.

  FIG. 3 is a diagram illustrating an example of a block diagram of the level detection unit 300 illustrated in FIG. Referring to FIG. 3, the level detection unit 300 includes a signal estimation unit 310 and a channel identification unit 330.

  The signal estimation unit 310 receives binary data obtained by binarizing the RF signal by a predetermined method. In order to obtain highly reliable binary data, the output of the Viterbi decoder 15 can be used as shown in FIG. That is, binary data obtained by viterbi decoding the RF signal is again used as the input of the signal estimation unit 310. However, binary data to be used as the input of the signal estimation unit 310 can be obtained using various binarization means such as using the output of the slicer 25 as the input of the signal estimation unit 310 as shown in FIG.

  The signal estimation unit 310 controls a number of delay units 311 to 315 and a channel identification unit 330 that respectively delay the binary data by the time interval of the input binary data, that is, the time corresponding to the sampling period of the RF signal. A selection signal generation unit 317 that generates a selection signal is included.

  The sample value of the RF signal is divided into several levels. Ideally, the sample value of the RF signal should have a certain level, but it contains errors due to various noise, factors such as optical disc quality and recording and / or playback device performance limitations. The channel identification unit 330 classifies each sample value of the RF signal into a corresponding level according to the selection signal output from the signal estimation unit 310. The channel identification unit 330 outputs LevelOutput 0 to LevelOutput m, which are average values of the sample values of the RF signals classified by level.

  The selection signal generation unit 317 receives the binary values that are the outputs of the delay units 311 to 315, determines the level corresponding to each sample value of the RF signal, and then corresponds to the determined level. The selection signal to be generated is generated and provided to the channel identification unit 330. That is, the signal estimation unit 310 determines the level to which the sample value of the RF signal that is the output of the delay unit 333 belongs, and then generates a selection signal corresponding to the determined level. According to the generated selection signal, the switch 339 outputs the sample value of the RF signal that is the output of the delay device 333 to one of the many average value filters 334 to 338.

  Each of the average value filters 334 to 338 outputs level output 0 to level output m of the average value of the sample values of the level-specific RF signals. Each average filter 334 to 338 may be implemented using a low-pass filter.

  The following formula (1) shows an example for obtaining LevelOutput 0 to LevelOutput m by the respective average value filters 334 to 338.

Updated level = previous level + (delayed input signal−previous level) / constant (1)
The larger the constant value in the equation (1), the smaller the updated level, and the slower the overall follow-up. In addition, when a level selected using the level value obtained in this way together with the Viterbi decoder is used in the Viterbi decoder, the signal can be decoded under the optimum conditions.

  According to the selection signal output from the selection signal generation unit 317, the switch 340 outputs one output among the level outputs 0 to level output m, which are the outputs of the average value filters 334 to 338, to the quality calculation unit 350. Since LevelOutput 0 to LevelOutput m are average values for each level of the RF signal from which noise has been removed, they can be regarded as an estimated value of an ideal level value.

  On the other hand, the RF signal input to the channel identification unit 330 in order to synchronize with the selection signal output from the selection signal generation unit 317 is delayed by a certain number of system clocks by a number of delay units 331 to 333.

  The signal characteristic determination unit 500 receives LevelOutput 0 to LevelOutput m, which are estimated values of the ideal level value of the RF signal output from the level detection unit 300, and calculates a predetermined value indicating the characteristic of the RF signal. Examples of the predetermined value indicating the characteristics of the RF signal include asymmetry, modulation ratio, and non-linearity.

  FIG. 4 is a diagram illustrating an example of a block diagram of the signal characteristic determination unit 500 illustrated in FIG. The signal characteristic determination unit 500 according to the present embodiment receives LevelOutput 0 to LevelOutput m, which is an estimated value of an ideal level value of the RF signal output from the level detection unit 300, and determines the asymmetry and modulation degree of the RF signal. Calculate.

  Asymmetry is a measure of how far the center of a signal with a predetermined period shorter than the maximum period is far from the center of the signal with the maximum period. The degree of modulation is a measure indicating whether the magnitude of a signal having a predetermined period shorter than the maximum period is much smaller than the magnitude of a signal having the maximum period.

  The following formula (2) shows an example for obtaining an asymmetry value.

下記式（３）は、変調度（ｍｏｄｕｌａｔｉｏｎｒａｔｉｏ）を求める一例を示す。

The following formula (3) shows an example for obtaining the modulation ratio.

ＡＬＬ‘１’ＬＥＶＥＬは、選択信号生成のために選択信号生成部３１７に入力される多数の２進値がいずれも“１”である場合に対応するレベルであって、光ディスクから得た最大周期信号の最大値である。ＡＬＬ‘０’ＬＥＶＥＬは、選択信号生成部３１７に入力される多数の２進値がいずれも“０”である場合に対応するレベルであって、前記最大周期信号の最小値を意味する。ＵＰＰＥＲ ＭＩＤＤＬＥ ＬＥＶＥＬ及びＬＯＷＥＲ ＭＩＤＤＬＥ ＬＥＶＥＬは、最大周期信号の周期より短い所定周期を有する信号の最大値及び最小値を各々意味する。

ALL′1′LEVEL is a level corresponding to the case where all of the binary values input to the selection signal generation unit 317 for generating a selection signal are “1”, and is the maximum period obtained from the optical disc. The maximum value of the signal. ALL'0'LEVEL is a level corresponding to the case where all the binary values input to the selection signal generation unit 317 are "0", and means the minimum value of the maximum periodic signal. UPPER MIDDLE LEVEL and LOWER MIDDLE LEVEL mean a maximum value and a minimum value of a signal having a predetermined period shorter than the period of the maximum period signal, respectively.

  Referring to FIG. 4, the signal characteristic determination unit 500 includes a first average value calculation unit 510, a second average value calculation unit 530, and a signal characteristic value calculation unit 550. The signal characteristic value calculation unit 550 receives ALL'1'LEVEL, ALL'0'LEVEL, UPPER MIDDLE LEVEL, and LOWER MIDDLE LEVEL described above, and calculates the asymmetry value and the modulation degree according to equations (2) and (3). To do.

  A plurality of binary values input to the selection signal generation unit 317 for generating a selection signal are input to determine a level corresponding to each sample value of the RF signal, and then a selection signal corresponding to the determined level Is generated and provided to the channel identification unit 330.

The run length means a number of consecutive “0” s or “1” s in a number of binary values input to the selection signal generation unit 317. For example, when the binary sequence input to the selection signal generation unit 317 is “11001”, the run length is 2. According to the present embodiment, even if run length is the same, DSV (digital sum)
There are different binary sequences of value). The DSV is a result of adding all the bits by substituting 1 when the data bit is 1 and -1 when the data bit is 0.

Even if the run length is the same, there are two cases where the DSV is different. If the average of the level value corresponding to the case where run length and DSV are the same is obtained, the average value at the desired run length and DSV can be obtained. Of these, UPPER is higher when DSV is larger.
When MIDDLE LEVEL, DSV is small, it is defined as LOWER MIDDLE LEVEL. According to the present embodiment, the first average value calculation unit 510 receives the level value corresponding to the case where the run length is P1 and the DSV is M1, and UPPER
Outputs MIDDLE LEVEL. The second average value calculation unit 530 receives a level value corresponding to the case where the run length is P2 and the DSV is M2, and outputs a LOWER MIDDLE LEVEL. In this embodiment, P1 and P2 are the same.

  FIG. 5 is a diagram illustrating an example of input / output signals of the signal characteristic determination unit 500 when a (1,7) code 5 tap is used. The fact that 5 taps are used means that by arranging four delay units at the front end of the selection signal generation unit 317, the binary values input to the selection signal generation unit 317 are all 5 as shown in FIG. If it is one.

Since five binary values are input to the selection signal generation unit 317, the selection signal generation unit 317 can generate selection signals indicating 32 levels. However, in the case of the (1,7) code, there is no 1T signal, so there are 16 levels when the level including the 1T signal is excluded. Of these, level 11111 is all'1 'level, and level 00000 is all'0' level. Level 11001 and level 10011 are levels including 2T signal, and are used when calculating UPPER MIDDLE LEVEL because DSV is 1, and level00110 and level01100 are levels including 2T signal, LOWER because DSV is -1.
Used when calculating MIDDLE LEVEL.

  There are non-linearities other than asymmetry and modulation degree as characteristic values indicating the characteristics of the RF signal. FIG. 6 is a diagram illustrating a sampled RF signal in the case of the (1,7) code. The nonlinearity of the RF signal shown in FIG. 6 can be obtained by the following equation (4).

前記式（４）でＩ_２Ｈは、（Ｉ_{２Ｈ＿ｆａｌｌ}＋Ｉ_{２Ｈ＿ｒｉｓｅ}）／２、Ｉ_４Ｈは、（Ｉ_{４Ｈ＿ｆａｌｌ}＋Ｉ_{４Ｈ＿ｒｉｓｅ}）／２、Ｉ_２Ｌは、（Ｉ_{２Ｌ＿ｆａｌｌ}＋Ｉ_{２Ｌ＿ｒｉｓｅ}）／２であり、Ｉ_４Ｌは（Ｉ_{４Ｌ＿ｆａｌｌ}＋Ｉ_{４Ｌ＿ｒｉｓｅ}）／２である。Ｉ_５ＰＰはＩ_５Ｈ−Ｉ_５Ｌである。

In the formula (4), I _2H is (I _{2H_fall} + I _{2H_rise} ) / 2, I _4H is (I _{4H_fall} + I _{4H_rise} ) / 2, I _2L is (I _{2L_fall} + I _{2L_rise} ) / 2, and I _4L is I _4L. (I _{4L_fall} + I _{4L_rise} ) / 2. I _5PP is I _5H -I _5L .

前記式（５）でＩ_{３Ｈ＿ｒｉｓｅ}はＩ_{３ＭＨ＿ｒｉｓｅ}、Ｉ_{３Ｈ＿ｆａｌｌ}はＩ_{３ＭＨ＿ｆａｌｌ}、Ｉ_{３Ｌ＿ｒｉｓｅ}はＩ_{３ＭＬ＿ｒｉｓｅ}であり、Ｉ_{３Ｌ＿ｆａｌｌ}はＩ_{３ＭＬ＿ｆａｌｌ}である。

In the formula (5), I _{3H_rise} is I _{3MH_rise} , I _{3H_fall} is I _{3MH_fall} , I _{3L_rise} is I _{3ML_rise} , and I _{3L_fall} is I _{3ML_fall} .

In the formula (4), LNL is an abbreviation for Level Non-Linearity, and PRNL is an abbreviation for Partial Response Non-Linearity. Referring to FIG. 6, if the RF signal has a perfect _linearity, values of the _{I 4H_rise} of _{I 4H_fall} must be identical. _Similarly, the values of _{I 3MH_fall} and _{I 3MH_rise,} must be identical to each other the values of _{I 2H_rise} and _{I 2H_fall.} However, when the RF signal has nonlinearity, the sample values corresponding to each other are not the same as shown in FIG. LNL and PRNL indicate the degree of nonlinearity of the RF signal, that is, the degree to which the sample values corresponding to each other are not the same. According to the above equations (4) and (5), it is possible to obtain a non-linear portion where a difference between the level of the positive part and the level of the negative part of the RF signal and a difference between the rising edge and the falling edge are obtained. There is an advantage.

  As described above, the asymmetry, the modulation degree, and the nonlinearity have been described as the characteristic values indicating the characteristics of the RF signal. However, various signal characteristic values can be obtained by using the detected level value which is the output of the level detecting unit 300 according to the present invention.

  FIG. 7 is a block diagram showing an example of a binary data detection apparatus including the signal characteristic determination apparatus according to the present invention shown in FIG. The binary data detection device detects binary data from the RF signal. 7 includes an analog / digital converter (ADC) 11, a DC offset removing unit 12, a PLL 13, an FIR filter 14, a Viterbi decoder 15, a level detecting unit 300, and a signal characteristic determining unit 500. Including a signal characteristic determination apparatus according to the present invention.

  The ADC 11 samples the RF signal at a predetermined period and outputs the sampled RF signal. The DC offset removal unit 12 receives the sampled RF signal that is the output of the ADC 11 and removes the DC offset value. The PLL 13 generates a system clock and provides it to the ADC 11 and the DC offset removal unit 12. In general, the Viterbi decoder 15 is designed under the assumption that the channel characteristics are constant, and thus the FIR filter 14 can be used to adjust the channel characteristics of a signal input to the Viterbi decoder 15.

  The Viterbi decoder 15 obtains binary data from the RF signal using the level value of the RF signal detected by the level detection unit 300.

  The binary data detection apparatus shown in FIG. 7 uses the Viterbi decoder 15 and the FIR filter 14 to improve the system performance and obtain a high quality output.

  FIG. 8 is a diagram showing another embodiment of the block diagram of the binary data detecting apparatus including the signal characteristic determining apparatus according to the present invention shown in FIG. The binary data detection apparatus shown in FIG. 8 obtains the asymmetry and modulation factor indicating the characteristics of the RF signal even when the simple binarizer (slicer) 25 is used without using the Viterbi decoder. It is for showing that it is possible.

  The present invention can also be embodied as computer-readable code on a computer-readable recording medium. Computer-readable recording media include all types of recording devices that can store data that can be read by a computer system. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy (registered trademark) disk, optical data storage device, and carrier wave (for example, transmission through the Internet). Also embodied in the form of The computer-readable recording medium can be distributed to computer systems connected via a network and stored and executed as computer-readable code in a distributed manner.

  In the above, this invention was demonstrated centering on the desirable embodiment. Those skilled in the art will appreciate that the present invention may be embodied in variations that do not depart from the essential characteristics of the invention. The scope of the present invention is expressed not in the above description but in the claims, and all differences within the equivalent scope should be construed as being included in the present invention.

11 Analog / Digital Converter (ADC)
12 DC offset removal unit 13 PLL
14 FIR filter 15 Viterbi decoder 25 Slicer
300 level detection unit 310 signal estimation unit 311 to 315, 333 delay unit 317 selection signal generation unit 330 channel identification unit 334 to 338 average value 339, 340 switch 350 quality calculation unit 500 signal characteristic determination unit 510 first average value calculation unit 530 Second average value calculator 550 Signal characteristic value calculator

Claims (20)

An analog-to-digital converter that receives a radio frequency (RF) signal, samples the radio frequency (RF) signal, and outputs the sampled RF signal;
A binary data detector for detecting binary data from the sampled RF signal and outputting the binary data;
A plurality of delay units for receiving the binary data and outputting each of the delayed binary data;
A selection signal generation unit that receives the binary data and the delayed binary data output from each of the plurality of delay units, and generates a selection signal;
A channel identification unit that receives the sampled radio frequency signal and outputs an average value of the sampled radio frequency signal according to the selection signal;
A signal characteristic determining unit that receives an average value of the sampled radio frequency signal and determines a characteristic value indicating the characteristic of the radio frequency signal using the average value of the received radio frequency signal. Characterization device.   The plurality of delay units delay the binary data during a time corresponding to a sampling period of the radio frequency signal, and output a predetermined number of consecutive bit information extracted from the binary data. The signal characteristic determination apparatus according to claim 1, wherein   The signal characteristic determination apparatus according to claim 1, wherein the channel identification unit includes a plurality of average value filters for obtaining an average value of the sampled radio frequency signals.   The signal characteristic determination apparatus according to claim 3, wherein the average value filter is a low-pass filter.   The apparatus of claim 1, wherein the binary data detection unit detects the binary data by viterbi decoding of the sampled radio frequency signal.   The signal characteristic determination apparatus according to claim 1, wherein the binary data detection unit detects the binary data by slicing the sampled radio frequency signal.   The signal characteristic according to claim 3, wherein the channel identification unit further includes a switch that outputs the radio frequency signal sampled by one filter among the plurality of average value filters according to the selection signal. Decision device.   8. The signal characteristic determination apparatus according to claim 7, wherein each binary data received by the selection signal generation unit corresponds to the sampled radio frequency signal received by the channel identification unit.   8. The channel identification unit according to claim 7, further comprising a plurality of delay units that delay the sampled radio frequency signal and output the delayed sampled radio frequency signal to the switch. Signal characteristic determination device. The average value output by the average value filter is the following equation:
4. The signal characteristic determination apparatus according to claim 3, wherein the average value is obtained by: updated average value = previous average value + (delayed input signal−previous average value) / constant.   In order to synchronize with the selection signal output from the selection signal generation unit, the sampled radio frequency signal input to the channel identification unit is delayed by the number of regular system clock cycles. The signal characteristic determination apparatus according to claim 1. The characteristic value indicates the asymmetry of the radio frequency signal, which is a scale indicating how far the center of the signal having a specific period is far from the center of the signal having the longest period, and the asymmetry is expressed by the following equation: :

Determined by
2. The UPPER MIDDLE LEVEL and the LOWER MIDDLE LEVEL in the equation are a maximum value and a minimum value of a signal having the specific period shorter than the period of the signal having the longest period. The signal characteristic determination apparatus described in 1. The characteristic value indicates a modulation ratio of the radio frequency signal, which is a scale indicating how small a signal having a specific period shorter than a longest period is compared with a signal having the longest period. , The modulation ratio is the following equation:

Determined by
The UPPER MIDDLE LEVEL and the LOWER MIDDLE LEVEL in the equation are the maximum value and the minimum value of the signal having the specific period shorter than the period of the signal having the longest period. The signal characteristic determination apparatus as described.   The signal characteristic determination apparatus according to claim 1, wherein the characteristic value indicates nonlinearity of the radio frequency signal. Sampling a radio frequency (RF) signal using an analog to digital converter;
Obtaining binary data from the sampled radio frequency signal;
Delaying the binary data using a plurality of delay units;
Generating a selection signal using the delayed binary data output from each of the plurality of delay units and the binary data obtained from the sampled radio frequency signal;
Obtaining an average value of the sampled radio frequency signal by the selection signal;
Determining a characteristic value of the radio frequency signal using an average value of the sampled radio frequency signal.   The step of delaying the binary data using the plurality of delay units delays the binary data during a time corresponding to a sampling period of the radio frequency signal and extracts the predetermined data extracted from the binary data. 16. The signal characteristic determination method according to claim 15, wherein a number of consecutive bit information is output.   The signal characteristic determination method according to claim 15, wherein the step of obtaining an average value of the sampled radio frequency signal is performed using a low-pass filter.   The method of claim 15, wherein the step of obtaining the binary data is performed by viterbi decoding of the radio frequency signal. In a computer-readable recording medium on which a program for realizing a signal characteristic determination method is recorded,
The method
Sampling a radio frequency (RF) signal using an analog to digital converter;
Obtaining binary data from the sampled radio frequency signal;
Delaying the binary data using a plurality of delay units;
Generating a selection signal using the delayed binary data output from each of the plurality of delay units and the binary data obtained from the sampled radio frequency signal;
Obtaining an average value of the sampled radio frequency signal by the selection signal;
And determining a characteristic value of the radio frequency signal using an average value of the sampled radio frequency signal. A computer-readable recording medium having recorded thereon a program for realizing a method. In an apparatus for detecting binary data from a radio frequency (RF) signal,
An analog / digital converter (ADC) that samples a radio frequency signal at a predetermined period and outputs the sampled radio frequency signal;
A DC offset canceller that receives the sampled radio frequency signal output from the analog / digital converter and cancels a DC offset value from the sampled radio frequency signal;
A PLL that generates a system clock signal and outputs the system clock signal to the analog / digital converter and the DC offset canceller;
A plurality of delay units for receiving binary data and outputting delayed binary data;
A selection signal generator that receives the binary data and the delayed binary data output from each of the plurality of delay units, and generates a selection signal;
A channel identification unit that receives the sampled radio frequency signal and outputs an average value of the sampled radio frequency signal according to the selection signal;
Receiving the average value of the sampled radio frequency signal and using the received average value of the sampled radio frequency signal to determine a characteristic value indicative of a characteristic of the radio frequency signal; Is a signal characteristic determination unit characterized by indicating one of asymmetry, modulation ratio, and nonlinearity of the radio frequency signal;
A Viterbi decoder that obtains binary data from the sampled radio frequency signal using an average value of the sampled radio frequency signal output from the channel identification unit;
An FIR filter for adjusting a channel characteristic of a signal input to the Viterbi decoder.

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