CN101930771B - Data recovery device and method - Google Patents

Abstract

The invention discloses a data recovery device and a method. The equalizer receives the radio frequency signal, adjusts the radio frequency signal according to the compensation signal, and outputs an equalized radio frequency signal. The cutting circuit cuts the balanced radio frequency signal according to the cutting level and outputs an alternating current radio frequency signal with a plurality of signal segments. The phase-locked loop receives and outputs a clock according to the phase of the alternating current radio frequency signal. The detection circuit calculates and outputs the time width of a plurality of signal segments according to the clock, and detects and outputs the sampling height of the plurality of signal segments. The compensation circuit calculates a ratio of sampling heights of at least two signal segments from the plurality of signal segments according to the output of the detection circuit, compares the ratio with a corresponding reference value, and outputs a compensation signal according to a comparison result.

Description

Data recovery device and method

technical field

The invention relates to a data recovery device and method, and in particular to a data recovery device and method suitable for an optical storage system. the

Background technique

General optical storage systems, such as compact disks (CDs) or digital versatile disks (DVDs) and other laser discs, use an optical disc drive (ODD) to reproduce their stored data during operation, The optical disc drive emits laser light on the surface of the laser disc and reads the signal reflected from the surface of the laser disc. The signal read from the surface of the laser disc is a radio frequency (RF) signal, so it includes non-linear channels with defocusing, inter-symbol interference (ISI), electrical delays, post-mass production The pit pattern formed on the recording medium by injection molding, the aging of the dye on the recording medium, or the surface scratches of the recording medium, etc., lead to poor recognition and read out distorted data. In addition, if high-speed reading is required, the problem of inter-symbol interference will be more serious. the

In order to take into account the transmission rate and signal quality, the existing optical storage system usually uses a partial response (PR) technology to allow inter-symbol interference within a certain range in order to perform high-speed reading. In detail, partial response methods correct for level errors to form digital data on which data operations can be performed. The formed digital data is decoded into the original stored digital data by the Viterbi decoding mechanism using the maximum likelihood (ML) method, which can minimize the error in theory, but it is quite complicated in implementation . For example, FIG. 1 is a waveform diagram of a frequency response of a conventional readout channel. Referring to Fig. 1, in the actual optical storage system, the frequency response Ch_1 of the actual read channel is not similar to the partial response channel PR1 and the partial response channel PR2, if the partial response channel PR1 or the partial response channel PR2 is used for reading, it will be There will be considerable error. Relatively speaking, if the partial response channel PR3 is used for reading, the correctness of the data can be improved. But to realize a similar partial response channel, more cost and more complicated circuit design may be required, while a less similar partial response channel can be realized in a simple way. Therefore, how to compensate the frequency response of the actual read channel so that it can be read with a less similar partial response channel is the mainstream topic of current research. the

Contents of the invention

Therefore, an embodiment of the present invention provides a data recovery device, wherein the channel characteristics for transmitting the radio frequency signal are judged by the sampling height (such as the amplitude) of the radio frequency signal, and the gain rise rate (roll) that the equalizer needs to compensate in the specified frequency range is adjusted. -up rate) to adjust the frequency response of the RF signal so that the RF signal can be read by the selected partial response channel, which can increase the recognizability of the RF signal in the selected partial response channel without selecting Specific partial response channels with greater similarity. the

An embodiment of the present invention provides a data restoration device, which includes an equalizer, a cutting circuit, a phase-locked loop, a detection circuit, and a compensation circuit. The equalizer receives the radio frequency signal and the compensation signal, adjusts the radio frequency signal according to the compensation signal, and outputs a balanced radio frequency signal. The cutting circuit is connected to the equalizer to receive the equalized radio frequency signal, and the cutting circuit cuts the equalized radio frequency signal according to the cutting level to output the AC radio frequency signal, wherein the AC radio frequency signal has multiple signal segments. The phase-locked loop is connected to the cutting circuit, and the phase-locked loop receives and outputs a clock according to the phase of the AC radio frequency signal. The detection circuit is connected to the cutting circuit and the phase-locked loop, and the detection circuit receives the AC radio frequency signal and the clock, calculates and outputs the time width of the AC radio frequency signal in multiple signal segments according to the clock, and the detection circuit detects and outputs multiple signals The sampling height of the segment. The compensation circuit is connected to the detection circuit and the equalizer, and the compensation circuit calculates the ratio based on the sampling height of at least two signal segments selected from the plurality of signal segments based on the output of the detection circuit, and compares the ratio with the corresponding reference value, and the compensation circuit is based on the comparison result Output compensation signal.

In an embodiment of the present invention, the two signal segments selected by the compensation circuit have different time widths. the

In an embodiment of the present invention, the above-mentioned equalizer includes an adaptive filter. The adaptive filter is connected to the cutting circuit, and the adaptive filter receives the compensation signal to adjust the frequency response of the radio frequency signal, and outputs a balanced radio frequency signal. the

In an embodiment of the present invention, the aforementioned compensation circuit includes a gain calculation circuit and a comparison circuit. The gain calculation circuit is connected to the detection circuit, and the sampling height of two signal segments is selected from the plurality of signal segments to calculate the ratio as the gain reduction rate. The comparison circuit is connected to the gain calculation circuit, and the comparison circuit receives the ratio, compares the relationship between the ratio and the corresponding reference value, and outputs a compensation signal accordingly. the

In an embodiment of the present invention, the aforementioned compensation circuit includes a gain calculation circuit and a comparison circuit. The gain calculation circuit is connected to the detection circuit, and the gain calculation circuit divides the multiple signal segments into m signal segment groups according to the time width, each signal segment group includes k signal segments with the same time width, and the gain calculation circuit calculates each of the above The average value of the k sampling heights in a signal segment group produces an amplitude average value, and at least two of the m amplitude average values corresponding to the above m signal segment groups are selected to calculate the ratio as the gain drop rate, where m and k is a positive integer. The comparison circuit is connected to the gain calculation circuit, and the comparison circuit receives the ratio of the gain reduction rate, calculates the operation result of the ratio of the gain reduction rate and the corresponding reference value, and outputs a compensation signal accordingly. the

In an embodiment of the present invention, the data restoration device further includes a bit stream generator, which is connected to the cutting circuit and the phase-locked loop, and outputs the bit stream with reference to the AC radio frequency signal and the clock. the

An embodiment of the present invention proposes a data restoration method. The steps of the data restoration method include adjusting the radio frequency signal according to the compensation signal to obtain a balanced radio frequency signal. Next, the equalized radio frequency signal is cut according to the cutting level to obtain an AC radio frequency signal, wherein the AC radio frequency signal has a plurality of signal segments. Next, a clock is obtained according to the phase of the AC radio frequency signal. Next, calculate time widths of the multiple signal segments according to the clock. Then, the sampling height of the AC radio frequency signal in multiple signal segments is detected. Next, the ratio is calculated from the sampling heights of at least two signal segments selected from the plurality of signal segments. Finally, compare the ratio with the corresponding reference value, and output a compensation signal according to the comparison result. the

Based on the above, the present invention adjusts the frequency response of the radio frequency signal so that the radio frequency signal can be read by the selected partial response channel, which can increase the recognizability of the radio frequency signal in the selected partial response channel, and can also reduce the cost of setting the channel and reduce complex circuit design. the

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail together with the accompanying drawings. the

Description of drawings

Fig. 1 is the oscillogram of the frequency response of existing reading channel;

Fig. 2 is a block diagram according to a kind of data recovery device of the first embodiment of the present invention;

Fig. 3 is a flow chart of a data recovery method provided according to the first embodiment of the present invention;

Fig. 4 is a waveform diagram of a kind of analog equalized radio frequency signal provided according to the first embodiment of the present invention;

Fig. 5 is the flowchart of a kind of data restoration method provided according to the third embodiment of the present invention;

Fig. 6 is the flowchart of a kind of data restoration method provided according to the fourth embodiment of the present invention;

Fig. 7 is a block diagram of a kind of data recovery device according to the fifth embodiment of the present invention;

FIG. 8 is a waveform diagram of a simulation of a gain rise rate of a compensated radio frequency signal at a specified frequency according to a fifth embodiment of the present invention;

FIG. 9 is a waveform diagram of a radio frequency signal for simulating compensation gain rising rate according to a fifth embodiment of the present invention. the

Description of main component symbols

200: data recovery device; 210: equalizer;

220: cutting circuit; 230: phase-locked circuit;

240: detection circuit; 250: compensation circuit;

700: data recovery device; 710: equalizer;

711: Adaptive filter; 750: Compensation circuit;

751: gain calculation circuit; 752: comparison circuit;

760: bit stream generator; PR1, PR2, PR3: partial response channel;

CH_1: actually read the frequency response of the channel; S310～S350: steps;

S541, S542: steps; S641-S643: steps;

A ₀ ～A ₄ : sampling height; T ₀ ～T ₄ : time width;

Z ₀ ～ Z ₅ : Zero crossing point; RF _AC : AC radio frequency signal;

RF _EQ : balanced radio frequency signal; Sc: compensation signal;

PCLK: Clock. the

Detailed ways

Therefore, in the embodiment of the present invention, when the radio frequency signal is received, the equalizer is used to adjust the frequency response characteristic according to the compensation signal to generate a balanced radio frequency signal. Segmentation of the signal is carried out by means of a segmentation circuit, so that the sampling height and time width of each signal segment can be defined. The phase-locked loop is used to obtain the clock signal required to define the time width. Then, the detection circuit can calculate the sampling height and time width between each signal segment to obtain the relationship between the sampling height and the time segment. Among them, since the same time width may correspond to multiple different sampling heights due to external influences, the detection circuit can output multiple amplitude signals. Here, an amplitude signal is a plurality of sampling heights corresponding to the same time width. The signal composed of height. Finally, the compensation circuit is used to calculate the gain roll-off rate based on the relationship between the time width output by the detection circuit and the amplitude signal, and calculate the difference between the gain roll-off rate and the corresponding reference value R, and output the compensation signal accordingly. the

Following the above, since the frequency response of the compensated RF signal is closer to the channel characteristics of the selected partial response channel, it can be used to increase the reliability of the RF signal, and the hardware design will not be too complicated. Embodiments of the invention will be described in detail below with reference to the accompanying drawings, which illustrate embodiments of the invention. In the following description, in order to present the consistency of the description of the present invention, in different embodiments, if there are elements with the same or similar functions and structures, the same element symbols and names will be used. the

FIG. 2 is a block diagram of a data recovery device according to the first embodiment of the present invention. Referring to FIG. 2 , in this embodiment, the data recovery device 200 includes an equalizer 210 , a cutting circuit 220 , a phase-locked loop 230 , a detection circuit 240 and a compensation circuit 250 . The cutting circuit 220 is connected to the equalizer 210 , the phase-locked loop 230 and the detection circuit 240 , the phase-locked loop 230 is connected to the detection circuit 240 , the detection circuit 240 is connected to the compensation circuit 250 , and the compensation circuit 250 is connected to the equalizer 210 . The detailed functions of the above-mentioned components will be introduced below. the

The equalizer 210 is used to receive a radio frequency signal RF from the channel. This radio frequency signal RF can be a data signal read by an access element (not shown in the figure) from the surface of a laser disc, and the equalizer 210 can receive a Compensate the signal Sc to adjust the radio frequency signal RF accordingly, and output the adjusted radio frequency signal as an equalized radio frequency signal RF _EQ . The cutting circuit 220 receives the balanced radio frequency signal RF _EQ , and cuts the balanced radio frequency signal RF _EQ according to the preset level or the DC level of the radio frequency signal RF _EQ as the cutting level, and cuts the balanced radio frequency signal RF _EQ into an AC signal , and output the balanced radio frequency signal after cutting as an alternating radio frequency signal RF _AC , wherein the alternating radio frequency signal RF _AC has multiple signal segments. The DC level of the above-mentioned radio frequency signal RF _EQ can be an average value of continuous analog integration, or a digital sum value (Digital Sum Value, DSV) average after digital cutting, which is usually achieved by feedback control. The AC radio frequency signal RF _AC can be provided to a next-stage circuit (not shown in the figure) for subsequent processing. The phase-locked loop 230 is used for receiving the AC radio frequency signal RF _AC and outputting the clock PCLK according to the phase of the AC radio frequency signal RF _AC .

Following the above, the detection circuit 240 is used to receive the AC radio frequency signal RF _AC and the clock PCLK, and calculate the time width of the AC radio frequency signal RF _AC in each signal segment according to the clock PCLK, and the detection circuit 240 samples the AC radio frequency signal RF _AC in each signal segment. The sampling height within each signal segment. In this embodiment, the "sampling height" of the aforementioned signal segment may be the amplitude of the signal segment. In another embodiment, the detection circuit 240 can sample a certain signal segment according to the clock PCLK to obtain multiple sampled values, and select the largest one from the multiple sampled values of the signal segment as the " Sampling Height". Those who apply this embodiment can define the "sampling height" according to their design requirements, for example, use all the sampling values (or part of the sampling values) of the same signal segment to calculate their average value as the "sampling height" of the signal segment.

The compensation circuit 250 selects at least two signal segments from the plurality of signal segments, and calculates a ratio of sampling heights of the two signal segments. By comparing the ratio with the corresponding reference value R, the compensation circuit 250 can obtain a comparison result and adjust the compensation signal Sc according to the comparison result, and output the compensation signal Sc to the equalizer 210 . A more detailed description will be given below in conjunction with the flow chart. the

Please refer to FIG. 2 and FIG. 3 . FIG. 3 is a flow chart of a data restoration method provided according to the first embodiment of the present invention. First, in step S310 , the equalizer 210 receives the radio frequency signal RF and the compensation signal Sc, adjusts the radio frequency signal RF according to the compensation signal Sc returned by the compensation circuit 250 , and outputs the equalized radio frequency signal RF _EQ to the cutting circuit 220 . In step S320 , the cutting circuit 220 cuts the equalized radio frequency signal RF _EQ according to the cutting level to output the AC radio frequency signal RF _AC , wherein the AC radio frequency signal RF _AC has a plurality of signal segments. In step S330, the detection circuit 240 receives the AC radio frequency signal RF _AC , and detects the sampling heights of the AC radio frequency signal RF _AC in a plurality of signal segments. In step S340, the compensation circuit 250 selects at least two signal segments from the above signal segments, and calculates a ratio according to the sampling heights of the two signal segments. In step S350 , the compensation circuit 250 compares the calculated ratio with the corresponding reference value R, and outputs the compensation signal Sc to the equalizer 210 according to the comparison result.

For example, FIG. 4 is a waveform diagram of an analog equalized radio frequency signal according to the first embodiment of the present invention. 2 and 4, when the cutting circuit 220 receives the balanced radio frequency signal RF _EQ and cuts according to the preset level or the DC level of the radio frequency signal RF _EQ as the cutting level, the balanced radio frequency signal RF _EQ and the cutting level can be obtained. A plurality of zero-crossing points (zero-cross) Z ₀ -Z ₅ of level crossing, wherein a signal segment is between every two adjacent zero-crossing points, and the cutting circuit 220 will equalize the radio frequency signal according to the above cutting level The RF _EQ output is an AC radio frequency signal RF _AC .

Referring to FIG. 2 and FIG. 4 , the detection circuit 240 receives the AC radio frequency signal RF _AC and the clock PCLK, and calculates the sampling height and time width of each signal segment in the AC radio frequency signal RF _AC . That is, the detection circuit 240 refers to the clock PCLK to calculate the time width T ₀ and the sampling height A ₀ between the zero-crossing points Z ₀ and Z ₁ , and then detects the time between the zero-crossing points Z ₁ and Z ₂ time width T ₁ and sampling height A ₁ , and then detect the time width T ₂ and sampling height A ₂ between zero-crossing points Z ₂ and Z ₃ , and the rest can be deduced by analogy. The detection circuit 240 can calculate from the clock PCLK that the time duration T ₀ includes three clocks (3T periods), the time duration T ₁ includes three clocks (3T periods), and the time duration T ₂ includes two clocks (2T periods).

The compensation circuit 250 selects two of the signal segments. For example, the compensation circuit 250 may select a signal segment between Z ₀ to Z ₁ and a signal segment between Z ₂ to Z ₃ , and then the sampling in the above two signal segments The height A ₀ and the sampling height A ₂ are calculated to obtain a ratio (for example, A ₂ /A ₀ ). The compensation circuit 250 can also select other two signal segments with different time widths.

The compensation circuit 250 can output the compensation signal Sc to the equalizer 210 according to the comparison result obtained by comparing the ratio with a preset corresponding reference value R. The above preset corresponding reference value R is also replaced with an ideal relative ratio value under the frequency domain response of the model when transforming the decoded partial response model. the

Compared with the data recovery device and method of the first embodiment, the second embodiment mainly differs in the method of calculating the ratio from the sampling height. More specifically, in this embodiment, a ratio is calculated as the gain reduction rate according to the sampling heights of two signal segments among the plurality of signal segments. the

2 and 4, the detection circuit 240 receives the AC radio frequency signal RF _AC and the clock PCLK, and calculates the sampling height and time width of each signal segment in the AC radio frequency signal RF _AC , that is, the detection circuit 240 refers to the clock PCLK To calculate the time width T ₀ between Z _{0 and} Z ₁ and the sampling height A ₀ , the time width T 1 between Z ₁ and Z ₂ and the sampling height A ₁ and the time width between Z ₂ and Z ₃ can be deduced by analogy T ₂ and sampling height A ₂ , etc. can be calculated from the clock PCLK. The time width T ₀ includes three clocks (3T cycles), the time width T ₁ includes three clocks (3T cycles), and the time width T ₂ includes two clocks (2T cycles). cycle). The detection circuit 240 selects signal segments with the same time width as a signal segment group. For example, the signal segment with a period of 3T in FIG. 4 is selected as a signal segment group, wherein the signal segment group has sampling heights A ₀ and A ₁ and so on. By calculating the average value of the sampling heights A ₀ and A ₁ in this signal segment group, the average sampling height of the 3T periodic signal segment group can be obtained. Similarly, signal segment groups with different time widths can respectively calculate corresponding average sampling heights. The detection circuit 240 outputs the average sampling heights corresponding to the signal segment groups with different time widths to the compensation circuit 250 .

The compensation circuit 250 selects the average sampling heights of at least two signal segment groups with different time widths from the average sampling heights of the signal segments with different time widths output by the detection circuit 240, and calculates the selected average sampling heights to obtain a ratio. The above preset corresponding reference value R is also replaced with an ideal relative ratio value under the frequency domain response of the model when transforming the decoded partial response model. the

Compared with the data restoration device and method of the first embodiment, the third embodiment is mainly different in that the gain reduction rate is calculated from the sampling height of two signal segments from the plurality of signal segments. More specifically, in this embodiment, referring to FIG. 2 , FIG. 3 and FIG. 4 , the detection circuit 240 receives the AC radio frequency signal RF _AC and the clock PCLK, and calculates the sampling height of each signal segment in the AC radio frequency signal RF _AC and time width. Wherein, FIG. 5 is a flow chart of a data restoration method provided according to the third embodiment of the present invention. Referring to FIG. 3 and FIG. 5 , in step S340 , the compensation circuit 250 selects at least two signal segments from the plurality of signal segments, and calculates a ratio according to the sampling heights of the two signal segments. In this embodiment, step S340 can be divided into sub-step S541 and sub-step S542.

In step S541 , the compensation circuit 250 selects the sampling height of two signal segments from the plurality of signal segments. For example, referring to FIG. 4 , the compensation circuit 250 can select the sampling height A ₀ of the signal segment (3T periodic signal segment) between the zero-crossing points Z ₀ to Z ₁ . Next, the compensation circuit 250 can select another signal segment with a different time width, for example, select the sampling height A ₃ of the signal segment (4T periodic signal segment) between zero-crossing points Z ₃ and Z ₄ . Therefore, the gain reduction ratio is A ₀ /A ₃ .

Please refer to FIG. 5 , in step S542 , the compensation circuit 250 calculates the two sampling heights obtained in the above step S541 to obtain a ratio (ie gain reduction rate). The compensation circuit 250 can compare the above ratio with a preset corresponding reference value R to obtain a comparison result. Finally, the compensation circuit 250 outputs a compensation signal to the equalizer 210 according to the aforementioned comparison result. the

Compared with the data restoration device and method of the second embodiment, the fourth embodiment mainly differs in the method of selecting two signal segments with different time widths and calculating the corresponding average sampling heights. The following is a detailed description in conjunction with the flow chart. Fig. 6 is a flowchart of a data restoration method provided according to the fourth embodiment of the present invention. Referring to FIG. 2 , FIG. 3 , FIG. 4 and FIG. 6 , in step S340 , the compensation circuit 250 selects at least two signal segments from the above signal segments, and calculates a ratio according to the sampling heights of the two signal segments. In this embodiment, step 340 can be divided into sub-step S641 , sub-step S642 and sub-step S643 . the

In step S641, the compensation circuit 250 selects signal segments having the same time width as a signal segment group. In step S642, the average sampling height of each signal segment group is calculated according to the plurality of sampling heights in the signal segment group. In step S643, the average sampling height of two signal segment groups is selected from the plurality of signal segment groups to calculate a ratio. the

Following the above, taking FIG. 4 as an example, the signal segment group corresponding to the 3T period has a sampling height A ₀ and a sampling height A ₁ , etc., so the compensation circuit 250 calculates the average sampling height of the two. The signal segment group corresponding to the 2T period includes the sampling height A ₂ and other sampling heights not yet drawn, so the compensation circuit 250 calculates the average sampling height of the 2T period signal segment group. Next, the compensation circuit 250 selects two signal segment groups from the above-mentioned multiple signal segment groups, for example, selects a signal segment group corresponding to a 3T cycle and a signal segment group corresponding to a 2T cycle, and calculates according to the average sampling height corresponding to the two The ratio is used as the gain reduction rate. Next, the compensation circuit 250 calculates the calculation result of the ratio of the gain reduction rate and the corresponding reference value R, so as to obtain the compensation signal Sc.

For example, in the HD-DVD system, the average sampling height of the 2T cycle and the 4T cycle can be used to calculate the ratio of the gain reduction rate; in the DVD system, the average sampling height of the 3T cycle and the 6T cycle can be used to calculate the gain. drop rate ratio. In addition, the compensation circuit 250 calculates the difference between the above-mentioned ratio and the corresponding reference value R, so as to output the compensation signal Sc to the equalizer 210 to adjust the frequency response of the radio frequency signal RF. Wherein, the corresponding reference value R can be a parameter set by the user, so that the frequency response of the radio frequency signal is closer to the channel characteristic of the selected partial response channel. the

It can be illustrated from this embodiment that by adjusting the frequency response of the radio frequency signal RF so that the radio frequency signal RF can be read by the selected partial response channel, the recognizability of the radio frequency signal RF in the selected partial response channel can be increased. the

It is worth mentioning that, although the data recovery device and method in the above embodiments describe a possible form, those with ordinary knowledge in the technical field should know that there are many ways to adjust the frequency response of the radio frequency signal RF. Therefore, the application of the present invention should not be limited to this possible form. Several implementations are given below so that those skilled in the art can further understand the spirit of the present invention and implement the present invention. the

Compared with the data restoration device and method of the first embodiment, the fifth embodiment mainly differs in compensating the frequency response of the radio frequency signal RF. More specifically, the first embodiment mentions how to obtain the compensation signal from the radio frequency signal RF, and in the fifth embodiment of the present invention, a method for compensating the radio frequency signal using the above compensation signal is described. the

In detail, FIG. 7 is a block diagram of a data recovery device according to a fifth embodiment of the present invention. Referring to FIG. 7 , in this embodiment, the data recovery device 700 includes an equalizer 710 , a cutting circuit 220 , a phase-locked loop 230 , a detection circuit 240 , a compensation circuit 750 and a bit stream generator 760 . Among them, the differences from the first embodiment lie in the equalizer 710 , the compensation circuit 750 and the bit stream generator 760 . Here, the cutting circuit 220 is connected to the equalizer 710, the phase-locked loop 230 and the detection circuit 240, the phase-locked loop 230 is connected to the detection circuit 240, the detection circuit 240 is connected to the compensation circuit 750, the compensation circuit 750 is connected to the equalizer 710, and the bit stream The generator 760 is connected to the cutting circuit 220 and the phase-locked loop 230 . The detailed functions of the above elements will be introduced below. the

The equalizer 710 may include an adaptive filter 711 for receiving the radio frequency signal RF from the channel, and the adaptive filter 711 may receive the radio frequency signal and adjust the frequency response of the radio frequency signal RF through the compensation signal Sc accordingly, and output the adjusted radio frequency signal as a balanced radio frequency signal RF _EQ . The compensation circuit 750 may include a gain calculation circuit 751 and a comparison circuit 752 . The gain calculation circuit 751 can receive the output of the detection circuit 240 , and calculate the gain reduction rate through the output of the detection circuit 240 , and output the gain reduction rate to the comparison circuit 752 . The comparison circuit 752 is connected to the gain calculation circuit 751, and can compare the difference between the gain reduction rate and the corresponding reference value R, so as to output a compensation signal. The bit stream generator 760 can refer to the AC radio frequency signal RF _AC and the clock PCLK, and output the frequency response adjusted AC radio frequency signal RF _AC as a bitstream. This bit stream BS can be provided to a next-level circuit (not shown in the figure) for subsequent processing.

In detail, the gain calculation circuit 751 calculates the frequency response of the frequency and decibel in each signal segment, thereby calculating the gain reduction rate. The gain calculation circuit 751 selects the sampling heights of two signal segments to calculate their ratio, and then outputs the ratio to the comparison circuit 752 . In this embodiment, a corresponding reference value R can be preset by the user. The comparison circuit 752 compares the above-mentioned ratio with the corresponding reference value R to determine how to compensate the gain reduction rate. Wherein, the spirit of comparing the above ratio with the corresponding reference value R is to correct the gain reduction rate to make it closer to the channel characteristics of the selected partial response channel. the

In some embodiments, comparison circuit 752 includes a subtractor (not shown). The subtractor is connected between the gain calculation circuit 751 and the equalizer 710 . The subtractor calculates the difference between the ratio output by the gain calculation circuit 751 and the corresponding reference value R, uses the difference as the compensation signal Sc, and outputs the compensation signal Sc to the equalizer 710 . the

For example, when the above-mentioned ratio output by the gain calculation circuit 751 is not greater than the corresponding reference value R, the comparison circuit 752 outputs a compensation signal Sc to instruct the adaptive filter 711 to increase the gain increase rate in the specified frequency, so as to adjust/ Compensate the radio frequency signal RF. When the above ratio output by the gain calculation circuit 751 is greater than the corresponding reference value R, the comparison circuit 752 outputs a compensation signal Sc to instruct the adaptive filter 711 to reduce the gain increase rate in the specified frequency compensation to adjust/compensate the radio frequency signal RF . the

For example, FIG. 8 is a simulation diagram of a characteristic curve of a gain rise rate of a compensated radio frequency signal at a specified frequency with different compensation parameters K according to the fifth embodiment of the present invention. Referring to Fig. 7 and Fig. 8, in the present embodiment, a possible method for compensating radio frequency signal RF is provided, and this compensation method can be represented by formula (1), and formula (1) is expressed as follows:

$\frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; K</span>}{\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="s"\; filenames="H2009101507351E00061.png"\; state="\{\{state\}\}">s</figure-callout></span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1.31703</span>}}{{\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="s"\; filenames="H2009101507351E00061.png"\; state="\{\{state\}\}">s</figure-callout></span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1.68495</span>}\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1.31703</span>}}<span\; class="notranslate">\; *</span>\frac{\mathrm{<span\; class="notranslate">\; 2.95139</span>}}{{\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="s"\; filenames="H2009101507351E00061.png"\; state="\{\{state\}\}">s</figure-callout></span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1.54203</span>}\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2.95139</span>}}<span\; class="notranslate">\; *</span>\frac{\mathrm{<span\; class="notranslate">\; 5.37034</span>}}{{\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="s"\; filenames="H2009101507351E00061.png"\; state="\{\{state\}\}">s</figure-callout></span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1.4558</span>}\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 5.37034</span>}}<span\; class="notranslate">\; *</span>\frac{\mathrm{<span\; class="notranslate">\; 0.86133</span>}}{\mathrm{<span\; class="notranslate">\; the\; s</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 0.86133</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Wherein, the compensation parameter K is used to control different gain rising rates to compensate the radio frequency signal RF. Continuing to refer to FIG. 7 and FIG. 8 , when the above ratio is not greater than the corresponding reference value R, the comparison circuit 752 can output a larger compensation parameter K to the adaptive filter 711, so that the adaptive filter 711 increases the gain increase rate. Conversely, when the above ratio is greater than the corresponding reference value R, the comparison circuit 752 can output a smaller compensation parameter K to the adaptive filter 711, so that the adaptive filter 711 reduces the gain increase rate to adjust the radio frequency signal RF. Selecting different compensation parameters K can make the frequency response of the radio frequency signal RF closer to the channel characteristics of the selected partial response channel, and improve reliability by reducing the Inter Symbol Interference (ISI) of the transmitted symbols. the

FIG. 9 is a waveform diagram of a normalized frequency domain response of an analog channel characteristic partial response according to the fifth embodiment of the present invention, with an oversampling rate of 1.25 times. Referring to FIG. 8 and FIG. 9, in this embodiment, the radio frequency signal RF originally belonging to PR (1, 2, 2, 2, 1) can make the frequency response of the radio frequency signal RF correspond to Adjusting to PR(1, 2, 2, 1), it can be seen from the figure that the gain reduction rate of the 2T periodic signal segment and the 4T periodic signal segment in the radio frequency signal RF becomes larger, making the relative difference between the two smaller. It should be noted that different partial response models may correspond to different gain reduction rates. the

It is worth mentioning that, in another embodiment of the present invention, the AC radio frequency signal and the clock of the above embodiment can also be received via the bit stream generator 760, and the frequency response adjusted radio frequency signal can be output as a bit stream . the

In summary, the above-mentioned embodiments of the present invention provide a data recovery device and method, wherein by detecting the gain drop rate of the radio frequency signal, comparing the gain drop rate with the channel characteristics of the radio frequency signal, adjusting the equalizer to a specified The frequency needs to compensate the gain rise rate to adjust the frequency response of the radio frequency signal, so that the radio frequency signal can be read by the selected part of the response channel, reduce the mutual interference of the transmitted symbols, and increase the response of the radio frequency signal in the selected part The identifiability of the channel without selecting a specific part of the response channel with a relatively large degree of similarity can reduce the cost of setting the channel and reduce the complexity of the circuit design. the

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: it still Modifications or equivalent replacements can be made to the technical solutions of the present invention, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention. the

Claims (14)

1. A data recovery device, comprising: An equalizer, receiving a radio frequency signal and a compensation signal, adjusting the radio frequency signal according to the compensation signal, and outputting a balanced radio frequency signal; A cutting circuit, connected to the equalizer, receives the equalized radio frequency signal, and cuts the equalized radio frequency signal according to a cutting level to output an AC radio frequency signal, wherein the AC radio frequency signal has a plurality of signal segments; A phase-locked loop, connected to the cutting circuit, receives and outputs a clock according to the phase of the AC radio frequency signal; A detection circuit, connected to the cutting circuit and the phase-locked loop, receives the AC radio frequency signal and the clock, calculates and outputs the time width of the AC radio frequency signal in the plurality of signal segments according to the clock , and detect and output the sampling height of the plurality of signal segments; and A compensation circuit, connected to the detection circuit and the equalizer, according to the output of the detection circuit, selects a sampling height of at least two signal segments from the plurality of signal segments to calculate a ratio, and compares the ratio Corresponding with a reference value, and outputting the compensation signal to the equalizer according to the comparison result. 2. The data recovery device according to claim 1, wherein the two signal segments selected by the compensation circuit have different time widths. 3. The data recovery device according to claim 1, wherein the equalizer includes an adaptive filter connected to the cutting circuit, receives the compensation signal to adjust the frequency response of the radio frequency signal, and outputs the Equalize the RF signal. 4. The data recovery device according to claim 3, wherein the adaptive filter adjusts a gain rising rate of the adaptive filter at a specified frequency according to the compensation signal. 5. The data recovery device according to claim 1, wherein the compensation circuit comprises: A gain calculation circuit, connected to the detection circuit, selects the sampling height of two signal segments from the plurality of signal segments and calculates the ratio as a gain reduction rate; and A comparison circuit, connected to the gain calculation circuit, receives the ratio, compares the relationship between the ratio and the corresponding reference value, and outputs the compensation signal accordingly. 6. The data restoration device according to claim 5, wherein the comparison circuit comprises a subtractor connected between the gain calculation circuit and the equalizer for calculating the ratio and the corresponding reference A difference of values is used as the compensation signal, and the compensation signal is output to the equalizer. 7. The data recovery device according to claim 1, wherein the compensation circuit comprises: A gain calculation circuit, connected to the detection circuit, divides the plurality of signal segments into m signal segment groups according to the time width, each signal segment group includes a plurality of signal segments with the same time width, and calculates each of the above The average value of multiple sampling heights in the signal segment group produces an amplitude average value, and at least two of the m amplitude average values corresponding to the above m signal segment groups are selected to calculate the ratio as a gain reduction rate, where m is a positive integer; and A comparison circuit, connected to the gain calculation circuit, receives the ratio, compares the relationship between the ratio and the corresponding reference value, and outputs the compensation signal accordingly. 8. The data recovery device according to claim 1, further comprising a bit stream generator connected to the cutting circuit and the phase-locked loop, and outputting a bit stream with reference to the AC radio frequency signal and the clock. 9. A data recovery method, comprising the following steps: adjusting a radio frequency signal according to a compensation signal to obtain a balanced radio frequency signal; cutting the equalized radio frequency signal according to a cutting level to obtain an AC radio frequency signal, wherein the AC radio frequency signal has a plurality of signal segments; obtaining a clock according to the phase of the AC radio frequency signal; calculating time widths of the plurality of signal segments according to the clock; Detecting the sampling height of the AC radio frequency signal in the plurality of signal segments; calculating a ratio from sampling heights of at least two signal segments selected from the plurality of signal segments; and The ratio is compared with a corresponding reference value, and the compensation signal is provided according to the comparison result. 10. The data restoration method according to claim 9, wherein the two signal segments selected in the step of calculating the ratio have different time widths. 11. The data restoration method according to claim 9, wherein adjusting the radio frequency signal according to the compensation signal, obtaining the balanced radio frequency signal comprises adjusting the frequency response of the radio frequency signal according to the compensation signal, obtaining the Equalize the RF signal. 12. The data recovery method according to claim 11, wherein the step of adjusting the frequency response of the RF signal comprises compensating the frequency response of the RF signal to a gain rising rate of a specified frequency according to the compensation signal. 13. The data recovery method according to claim 9, wherein according to the ratio, comparing the relationship between the ratio and the corresponding reference value, and obtaining the compensation signal accordingly comprises calculating the ratio and the corresponding A difference of the reference value is used as the compensation signal. 14. The data recovery method according to claim 9, wherein the step of calculating the ratio from the sampling heights of at least two signal segments in the plurality of signal segments comprises: dividing the plurality of signal segments into m signal segment groups according to the time width, each signal segment group comprising k signal segments having the same time width; calculating an average of the sample heights of the k segments in the same segment group to produce an average sample height; and The ratio is obtained by calculating the aforementioned two average sampling heights from at least two of the m average sampling heights corresponding to the m signal segment groups, wherein m and k are positive integers.

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