CN1158776C

CN1158776C - Full and half-rate signal space detection for channels with a time-varying mtr

Info

Publication number: CN1158776C
Application number: CNB988137852A
Authority: CN
Inventors: B・鲁布; B·鲁布; 沙菲; H·R·沙菲
Original assignee: Seagate Technology LLC
Current assignee: Seagate Technology LLC
Priority date: 1998-02-24
Filing date: 1998-09-09
Publication date: 2004-07-21
Anticipated expiration: 2018-09-09
Also published as: WO1999044295A1; GB2349251B; GB0017526D0; GB2349251A; DE19882980T1; CN1301432A; JP2002505540A

Abstract

A detector (400) of the present invention is provided to detect data values with a data signal that is sampled to provide temporally separated data samples. A first detector portion (462, 452, 458) is configured to determine the location of a first sample vector in a first signal space. A second detector portion (454, 456, 460) is configured to determine the location of a second sample vector in a second signal space. The second detector portion determines the location by using a logic statement to combine a plurality of location indicators. Each location indicator provides the location of the second sample vector relative to a respective boundary surface. The form of the logic statement is independent of the values of the location indicators. In addition, each location indicator is independent of all other location indicators.

Description

Sometimes become channel full and half speed signal space detection method and the device of MTR

Invention field

The present invention relates to disc driver.The invention particularly relates to the data detector in the disc driver, wherein, data detector detects according to having time variation limited code and comes coded data.

Background of invention

Typical disc driver comprises one or more disks, and disk is installed in an axle or the rotating shaft and rotation thereupon.Typical disc driver also comprises the transducer by the fluid dynamic air bearing supporting of flying on each disk.The air-supported data head that is referred to as of transducer and fluid dynamic.Driver controller is used for traditionally according to the order from the host computer system reception, the control disc driver.Driver controller control disc driver, from search disk information, and with information stores to disk.

In traditional disc driver, electromechanical actuator moves in a negative feedback closed circuit servo system.Actuator moves radially data head to carry out the magnetic track seek operations on magnetic disk surface, and transducer is directly remained on a magnetic track top on the magnetic disk surface, carries out magnetic track and follows operation.

Information normally is stored in the concentric magnetic track on the magnetic disk surface, by write signal is delivered on the data head, and information is write on the magnetic disk surface of the data that representative will store.From the search disk data time, driver controller controller electric actuator, thus data head flies on disk, and produce a read signal according to canned data on the disk.Read signal is normally through overregulating, and the restoring data by driver controller decoding subsequently.

Typically reading channel comprises data head, preliminary treatment logical circuit (as pre-amplification circuit and filter circuit), data detector and goes back primary circuit and error detection occurs and correcting circuit.Reading channel normally is arranged in the driver controller relevant with disc driver.

In disc driver, the error rate with respect to figure place that importantly will write down (bit error rate) remains on the low relatively level.In order to improve the bit error rate performance in the disc driver,, need to adopt some Maximum likelihood sequence detection (MLSD) method perhaps in order to improve the linear recording density in the disc driver.These methods can realize with well-known Viterbi (Viterbi) rule.Yet it is very big directly adopting MLSD method expense.For example, the later channel response of forward direction filtering is very long usually, and may contain 10 or more.So Vitebi detector needs 2 ^10-1Individual state, very complicated in actual use.So people have studied other technology, attempt to reduce complexity but still can provide near the direct getable result of MLSD method.

A kind of technology is by removing some items with feedback the item that quantity reduces to be carried out the Viterbi rule.For example, remove all items and only keep two (and comprising primary cursor), make Vitebi detector have only four kinds of states.This detector is called brief status switch estimation device (RSSE).

Another kind of technology is to select a channel response target, and it is not a kind of target of albefaction, but the item number that is had still less.In such system, developed local acknowledgement's target.In these targets, there is one to be called enhancing expansion partial response maximum likelihood (E ²PRML) target.

Under high record density, observe, for local acknowledgement's channel of some high-order (as E ²The PRML channel), the main error event that detector ran into (two list entries poor) that adopts this local acknowledgement target normally+/-form of (2 ,-2,2).Such mistake normally in sample time during three of internal shifts, causes vice versa when perhaps four dislocations become one two.

What the present invention is directed to is exactly these problems, and compared with prior art, also has other advantage.

The present invention includes following advantage.At first, the present invention has realized the signal space detector of MTR encoding channel.Secondly, because channel response is not forced to limit, so detector can be used in widely in the user density scope.Simultaneously, signal space detector adopts MTR=2 restriction and time variation MTR sign indicating number to realize according to the present invention.Adopt the MTR=2 sign indicating number, detector is providing significant gain on the 3D-110 detector under the lower user density.Adopt the time of higher rate to change the MTR sign indicating number, particularly under higher density, can further improve performance.

Summary of the invention

At present, studying a kind of coding of new relatively grade.This coding comprises maximum conversion operation (MTR, maximum transition run) sign indicating number, this sign indicating number be proposed as a kind of under high density maximum likelihood sequence detector (MLSD) or more high-order local acknowledgement channel as strengthening expansion partial response maximum likelihood rate (E ²PRML) remove the method for main error event in.The MTR sign indicating number is used for increasing the Euclidean distance between the data sample in the magnetic recording channel.

For example, the MTR=2 sign indicating number has limited the operation that is transformed into the two in write current continuously.In essence, the MTR=2 sign indicating number has been removed all coded data sign indicating number types that contain twice above continuous conversion.Therefore, the MTR=2 sign indicating number has also removed down and the main error event of MLSD detector in the high-order PR channel of high record density.

Adopt MTR restriction (constraint), developed a kind of detector, being called is the 3D-110 detector, and its performance can be comparable with the fixed delay tree search (FDTS/DF (2)) of adopting the degree of depth 2 decision-feedback under high signal density.This detector is by considering that three vectors that receive sampling constitute in the three dimensions.Calculate three planar boundaries, and be used for signal space is divided into two zones, each zone corresponding to current position of just handling+1 or-1 judgement.The 3D-110 detector also comprises a forward-direction filter, (precursor) intersymbol interference (ISI) item before this filter removal cursor, and (post cursor) ISI item is respectively 1 and 0 after forcing cursor, cursor also is normalized to 1 here.Feedback filter is used and is removed all items, but cursor ISI item after only staying two.So, propagate by detector owing to be free from mistakes, the discrete time channel impulse response of equivalence can be expressed as 110.This restriction of channel response is used for making the designs simplification of detector.

Although magnetic channel natural response is near 110 targets under the high record density, it has obviously departed from 110 targets under the low packing density.So restriction causes the performance degradation compared with FDTS/DF (2) to the impulse response of these specific 110 targets, particularly under lower packing density.Even under high density, actual components also can make channel response depart from 110 targets in the detector.For example, adopt limited length finite impulse response (FIR) (FIR) filter can produce this departing from.

So, although the 3D-110 channel is compared with other detector (as more complicated FTDS/DF (2) detector), aspect performance and/or the property simplified tangible advantage being arranged, there is above-mentioned shortcoming really in it.

What the present invention relates to is a kind of system at such and such problem, and has other advantage.

Detector of the present invention is used for detecting sampled with the data value in the data-signal that the discrete data sampling is provided temporarily.First detector portion is configured to determine the position of first sampling vector in first signal space.Second detector portion that constitutes is used for determining the position of second sampling vector in the secondary signal space.Second detector portion determines to adopt logic to explain the position that a plurality of location pointers are combined.Each location pointer provides the position with respect to second sampling vector of each border surface.The form of logic statement is the value that is independent of location pointer.In addition, each location pointer is to be independent of every other location pointer.

The accompanying drawing summary

Fig. 1 is the vertical view that has removed the top shell and adopted the disc driver of characteristic of the present invention.

Fig. 2 is the high-level block diagram of disc driver among Fig. 1.

Fig. 3 is a schematic diagram of describing the mark that magnetic track and relevant reading circuit use with better description number.

Fig. 4-1 and 4-2 describe is corresponding to the graphical diagram (symbol constellation) according to the detector of one aspect of the present invention.

Fig. 5-1 and 5-2 are the oscillograms of describing the highdensity main error event of MLSD.

Fig. 6 is the block diagram of describing according to the detector arrangement of one aspect of the present invention.

What Fig. 7-1 and 7-2 described is the FTDS/DF tree that is used for describing according to the detector operation of one aspect of the present invention.

Fig. 8 is a block diagram of describing a kind of example structure of 3D/4D signal space detector of the present invention.

Fig. 9 is a block diagram of describing a kind of example structure of 1/2nd speed 3D/4D signal space detectors of the present invention.

The detailed description of preferred embodiment

With reference to Fig. 1, the spinning disk drive system that is suitable for adopting principle of the present invention is shown in schematic form, and total representing with label 110.A plurality of information-stored disks 112 are installed on the shell 116 interior spindle motor assemblies 114.Each disk 112 has a plurality of concentric circles recording tracks, is used for recorded information, and represents with 118.Each magnetic track 118 is divided into a plurality of sectors again, represents with 120.Data can be by storing on the disk 112 with reference to specific magnetic track 118 and sector 120 or therefrom retrieving.Actuator arm assembly 122 preferably is rotatably installed on the angle of shell 116.Actuator arm assembly 122 has a plurality of magnetic head horizontal stand assemblies 124, and each magnetic head horizontal stand assembly 124 has a slide block 125 with W head, or transducer 126, is used for reading information and information being write on the disk 112 from disk 122.Voice coil motor 128 accurately makes actuator arm assembly 122 rotate back and forth, thereby transducer 126 is crossed on disk 112 mobile along camber line 130.The position of control circuit 132 control transducers 126, and handle the information of writing on the disk 112 or receiving from disk 112.

Fig. 2 is the high-level block diagram of the control circuit 132 of disk drive system 110.Microcontroller 134 is directly carried out all major functions of disk drive system 110.The read/write support of representing with label 136 links to each other with microcontroller 134 by conventional data, address and control bus 140 with actuator controller 138 with an interface control circuit and a motor.Circuit 136 provides a hardware interface by communication bus 142 usually between disk drive system 110 and mainframe computer system (not shown).Simultaneously, circuit 136 provides an interface usually between motor and actuator controller 138 and read/write channel 144.Read/write channel 144 is from preamplifier 143 received signals, and preamplifier 143 is from transducer 126 received signals.Read/write channel 144 is as microcontroller 134 and the interface of transducer 126 on circuit 145.Read/write channel 144 also provides signal to motor and actuator controller 138 on circuit 146.Controller 138 is as microcontroller 134 and the interface of electric machine assembly 114 on circuit 148, and microcontroller 134 and the interface of actuator arm assembly 122 on circuit 150.

Fig. 3 is magnetic channel 160 and the schematic diagram of reading block of channels 162, is used for understanding better employed label.Just as known to the people like that, channel 160 comprises recording medium, as disk 112 and transducer 126.Read block of channels 162 and comprise adder 164, pre-filter (front filter) 166, sampler 186, forward-direction filter (forward filter) 168, adder 170, detector 172 and feedback filter 174.Reading block of channels 162 normally is applied in the read/write channel shown in Figure 2 144.The input 176 of magnetic channel 166 is a data bit sequence preferably, the data bit a of cycle current time k _kExpression.According to one aspect of the present invention, preferably, the input bit sequence row are encoded according to forcing the coding that makes the restriction of MTR=2 sign indicating number, and the position provides with NRZ (NRZI) form, wherein, " 1 " is to be represented by conversion, and " 0 " is represented by non-conversion.

When from magnetic channel read data bit, they are as read back waveform 178.Read back waveform 178 is damaged by noise 180 usually, and noise 180 is to use the n (t) that is added on the read back waveform 178 by adder 164 to represent.Should be noted that noise n (t) and adder 164 represent to illustrate as just the noise of damaging read back waveform 178, is not the part of actual hardware structure therefore.No matter be under any situation, noise n (t) can occur, and can damage read back waveform 178, forms the read signal of damaging 182.

The read signal of damaging 182 is provided to pre-filter 156.For instance, pre-filter 156 is a kind of simulation low-pass filters, and it has avoided obscuring and the elimination high-frequency noise, and the output 184 that will leach offers sampler 186.186 pairs of outputs that leach 184 of sampler are taken a sample, and can realize with analog-digital converter.The sampled signal that sampler 186 produces is provided to forward-direction filter 168.

Forward-direction filter 168 preferably works independently, or works with other filtering, so that the noise whitening in the read back waveform, and provides modified read back waveform 188 (also to be labeled as r to adder 170 _k).The example of a forward-direction filter 168 is finite impulse response (FIR) (FIR) filters, and it comprises a plurality of taps.Forward-direction filter 168 has removed interference (ISI) item between all cursor front signals.The ISI item allows to get their value naturally behind the cursor, and this is because of being not have mandatory restriction to channel coefficients.Detector 172 provides a sequence 190 (to be also referred to as in its output place _k).

Output _kBe input data sequence a _kA kind of estimation.Output _kAlso be provided to feedback filter 174, this filter is used for providing feedback signal 192 to adder 170.Feedback signal 192 is added to the output r of forward-direction filter 168 _kOn.The output that is combined in adder 170 194 of these signals (also is designated as y _k) be provided to judgment device 172.In an embodiment of the present invention, feedback filter 174 is to be used for removing all items, only stays ISI item behind two cursors.In another kind of embodiment, be used for removing all except that ISI item behind three cursors.

For removing the feedback filter that removes consequent all of two cursors, suppose that the judgements before the judgment device 172 all are correct, equivalent discrete time channel response comprises three, and be designated as (1, f ₁, f ₂).

So, at moment k, the noiseless of judgment device 172 input y _kCan be write as:

y _k=a _k+ f ₁a _K-1+ f ₂a _K-2 Equation 1

Here, a _kIt is the input data bit when moment k.

Three dimensional signal spatial detector (3D-SSD) can realize by at first considering a graphical diagram in the three dimensions.As inciting somebody to action in greater detail hereinafter, a kind of like this detector can represent all possible sign map of input data sequence in three dimensions.Subsequently, detector obtains a kind of sampling vector, and it comprises the contribution from a plurality of inputs sampling, and in these samplings each is made up of a plurality of of input data sampling in the expression input sampling sequence.Subsequently, sampling vector is transformed in the three dimensions identical in the graphical diagram.Detector is judged which possible data symbol sampling vector constantly time the near each in three dimensions subsequently.This with determine to fixed delay detector (as the FDTS/DF detector) or in advance partial response channels (as Patel, Rutledge and So in " six samplings in advance 1; 7 ML detect the performance data (PerformanceData For A Six-Sample Look-Ahead 1; 7 ML Detection Channel) of channel " IEEE Trans.Magn.Vol.29, No.6, pp.4012-4014, described such in 1993 11 months, and people such as Yamasaki is at " A1 with analogue noise albefaction detector; 7 coding EEPR4 read channel IC (A1,7Code EEPR4 Read Channel IC With Analog Noise Whitened Detector) " PROC. OF ISSCC, 1997, described in the pp.316-317) the observation sampling value and to require the path of the corresponding minimum euclid distance between the sampling value be similar.

Each that point to that different detectors judge should be separated by boundary face possible symbol.Planar boundary is made up by logic rules, thereby signal space is separated into two zones, and the detector judgement with+1 is corresponding, and another detector with-1 is judged corresponding.Where drop in the trivector space with respect to boundary face according to sampling vector, send binary system by detector 172 and judge as detector output _kSuch just as will be described below, by removing unnecessary face, and also can by remove than the minimum euclid distance relevant with this coding far away the symbol that separates of Duoing, detector arrangement is simplified.

Fig. 4-1 and 4-2 describe is to analyze have the formation sampling vector vector space of detector of list entries of three items of (be also referred to as and observe vector).More particularly, Fig. 4-1 and 4-2 describe is to be the graphical diagram of Lorentz channel under 2.25 the character density in density.This graphical diagram has a y _k(also representing), and y ' with label 200 _K-1(also representing) with label 202.Graphical diagram shown in Fig. 4-1 and the 4-2 also comprises the 3rd axle y " _K-2(also representing) with label 204.Axle y " _K-2Extend in Fig. 4-1 and the plane, 4-2 place, also extend from Fig. 4-1 and plane, 4-2 place.

As described in will be below, according to some symbol of MTR restriction removing, and the symbol that can represent the three dimensional viewing vector that institute might remainder be mapped in Fig. 4-1 and the described graphical diagram of 4-2.Constitute planar boundary subsequently, so that those symbols are divided in the three dimensions that is limited by graphical diagram.Observe vector and be transformed this graphical diagram (constellations) subsequently, and detector according to the observation vector in graphical diagram with respect to the position of planar boundary, a judgement is provided.

The axle of graphical diagram is defined as follows:

y _k=a _k+ f ₁a _K-1+ f ₂a _K-2 Equation 2

Y ' _K-1=a _K-1+ f ₁a _K-2 Equation 3

Y " _K-2=a _K-2 Equation 2

Here, y ' _K-1And y " _K-2Ordinary representation is owing to deleted judgement in the past (promptly at the judgement at moment k place _K-3And _K-4) and have the detector input of intersymbol interference at moment k-1 and k-2 place.Because detector is handled as observing vector three input samplings, thus in testing process each k place constantly, must be to an input a _K-2Judge.

Table 1

Index	(a _k-2，a _k-2，a _k)	(y’，y’ _k-1，y” _k-2)
Index	(a _k-2，a _k-2，a _k)	(y’，y’ _k-1，y” _k-2)	0	(+1，+1，+1)	(+1+f ₁+f ₂，+1+f ₁，+1)
1	(+1，+1，-1)	(-1+f ₁+f ₂，+1+f ₁，+1)	0	(+1，+1，+1)	(+1+f ₁+f ₂，+1+f ₁，+1)
1	(+1，+1，-1)	(-1+f ₁+f ₂，+1+f ₁，+1)	2*	(+1，-1，+1)	(+1-f ₁+f ₂，-1+f ₁，+1)
3	(+1，-1，-1)	(-1-f ₁+f ₂，-1+f ₁，+1)	2*	(+1，-1，+1)	(+1-f ₁+f ₂，-1+f ₁，+1)
3	(+1，-1，-1)	(-1-f ₁+f ₂，-1+f ₁，+1)	4	(-1，+1，+1)	(+1+f ₁-f ₂，+1-f ₁，-1)
5	(-1，+1，-1)	(-1+f ₁-f ₂，+1-f ₁，-1)	4	(-1，+1，+1)	(+1+f ₁-f ₂，+1-f ₁，-1)
5	(-1，+1，-1)	(-1+f ₁-f ₂，+1-f ₁，-1)	6	(-1，-1，+1)	(+1-f ₁-f ₂，-1-f ₁，-1)
7	(-1，-1，-1)	(-1-f ₁-f ₂，-1-f ₁，-1)	6	(-1，-1，+1)	(+1-f ₁-f ₂，-1-f ₁，-1)

What table 1 was described is can be with observing all possible list entries that vector is represented.Table 1 comprises that one relates to and 2 ⁿ(n=3) the index of the individual possible corresponding index 0-7 of symbol here.Table 1 also comprises according to a _K-2, a _K-1, a _kThe possible symbol that writes out, and the y that writes out according to channel response is provided _k, y ' _K-1, y " _K-2The estimation of axle.

What Fig. 5-1 and 5-2 described is waveform 206,208,210 and 212, and its is represented under high density and is the viewed main error event of MLSD detector under the high-order local acknowledgement target.Among Fig. 5-1, error event be three digit wave forms 206 displacement time interval with produce three of displacement 208 o'clock produced.Among Fig. 5-2, on the contrary error event detect four digit wave forms 210 as two 212 or the time produce.

In order to remove so main error event, preferably according to not allowing three MTR=2 restriction that the input data are encoded.So, in table 1, according to _K-3Value, do not allow symbol 2 or symbol 5, this is because there are three in these symbologies.For example, work as _K-3=+1 o'clock, symbol 5 and corresponding from the input bit sequence row of (+1 ,-1 ,+1 ,-1), it contains three continuous conversions, and must be removed by the same token, works as _K-3, then must remove symbol 2 at=-1 o'clock.

Graphical diagram shown in Fig. 4-1 has all and is mapped to the interior possible symbol of this figure, supposes _K-3=-1.Notice that symbol 2 is not to be mapped to the graphical diagram shown in Fig. 4-1.Similarly, the graphical diagram shown in Fig. 4-2 have might be mapped to possible symbol in this figure, here, _K-3=+1.Notice that symbol 5 has been removed.

With y " _K-2=+1 and-1 corresponding symbol represent with x and 0 respectively.At symbol x and 0 time label index.

Fig. 4-1 and 4-2 have also described and have been used for dividing segmentation plane A, B, C and the D that is mapped to the various symbols in the graphical diagram.At the beginning, notice and adopted four segmentation plane.In order to simplify the structure of detector, number of planes is limited in 3 (for example, plane C and D are combined form the new plane E that is discussed below) yet just as will be described hereinafter.In order further to simplify the structure of detector, also should limit the direction on plane.

Plane A is used for

symbol

0 and 4 is separated (and the

symbol

1 and 5 among Fig. 4-1).For the detector of the best, decision boundaries is to connect a pair of binary plane of line with the symbol that separates.Yet, for the sake of simplicity, should restriction system, make the plane can be separately, but projection be separately on a surface with their with two symbols (symbol) in the three dimensions.This restriction is by picking up the coordinate of two intersymbol spacing maximum effect to be realized.Can see since with an input position a _K-2Difference judge that two corresponding symbols separate easily on this, so y " _K-2Coordinate should keep.And remaining two coordinate (except very low character density), y " _K-1Coordinate is than y to the distance between

symbol

0 and 4 _kCoordinate plays a part bigger.So symbol is projected to y ' _K-1Y " _K-2The surface.Therefore, divisional plane A is limited in only perpendicular to y ' _K-1Y " _K-2The surface rotation.

Therefore, plane A is selecting lip-deep projection represent a line, and the direction of this line is when the face permission is rotated and change.All points have symbol with projection to identical distance on the line.

From table 1, can see y ' _K-1Y " _K-2The coordinate of

symbol

0 and 4 projections is respectively (1-f on the surface ₁,+1) and (1-f ₁,-1).So, can obtain the equation of plane A as described below:

(y’ _k-1-(-1+f ₁)) ²+(y” _k-2-1) ²

=(y ' _K-1-(1-f ₁)) ²+ (y " _K-2+ 1) ² Equation 5

This expression formula can be simplified and obtains

Y " _K-2+ f ₁Y ' _K-1-f ₁=0 equation 6

Adopt similar process, the divisional plane equation that symbol 3 and 7 (also can be the

symbol

2 and 6 among Fig. 4-2) is separated can write out following form:

Y " _K-2+ f ₁Y ' _K-1+ f ₁=0 equation 7

Work as _K-3=-1 o'clock, plane C was with symbol 3 and opened in 5 minutes.Plane C is limited in only perpendicular to y _kY " _K-2Surface rotation, this is because the coordinate that intersymbol spacing is played maximum effect is corresponding to y _kAnd y " _K-2The coordinate of axle.By finding two symbols at y _kY " _K-2The line of lip-deep projection five equilibrium obtains the plane equation.

To working as _K-3=+1 o'clock repeats this operation again to symbol 2 and the plane D that opened in 4 minutes.

These processes will cause following four location identifier equatioies:

A:sgn (y " _K-2+ f ₁Y ' _K-1-f ₁) equation 8

B:sgn (y " _K-2+ f ₁Y ' _K-1-f ₁) equation 9

C:sgn (y " _K-2-(f ₁-f ₂) y _k-(f ₁-f ₂)) equation 10

When, _K-3=-1

D:sgn (y " _K-2-(f ₁-f ₂) y _k+ (f ₁-f ₂)) equation 11

When, _K-3=+1

Location identifier equation C and D can also be combined, provide:

E:sgn (y " _K-2-(f ₁-f ₂) y _k+ (f ₁-f ₂) _K-3) equation 12

Equation 12 can also be by being provided with (f ₁-f ₂)=1 and further simplifying.Because under interested lower channel density, two symbols that separated by this plane are than dividing the symbol of opening at a distance of farther by plane A and B, so this simplification has a negative effect to the performance of detector.So the minor variations of planar orientation and position can not influence the sampling that the received relative position with respect to this plane.So equation 12 can be simplified as follows:

E:sgn (y " _K-2-y _k+ _K-3) equation 13

Y ' replaces from

equation

3 and 4 _K-1And y " _K-2, for three location identifiers, obtain following relational expression:

A:sgn (y _K-2-f ₁y _K-1+ Δ A) equation 14

B:sgn (y _K-2-f ₁y _K-1+ Δ B) equation 15

E:sgn (y _K-2-y _K-1+ Δ E) equation 16

Here, value Δ A, Δ B and Δ E are the deviants that is provided by following formula:

Δ A=(f ₁-f ₁f ₂) _K-3-f ₂ _K-4-f ₁Equation 17

Δ B=(f ₁-f ₁f ₂) _K-3-f ₂ _K-4-f ₁Equation 18

Δ E=(f ₁+ 1) _K-3-f ₂ _K-4Equation 19

Usually, deviant is as the short FIR filter realization with binary system input, two input multiplexers or question blank.

By test point in the three dimensional signal space move and measuring point with respect to the relative position on plane, can carry out decision logic.By finding in the graphical diagram the symbol of close test point, obtain the output of relevant detection device.Subsequently, situation about judging by the identical output that will obtain self-detector combines, and obtains logic rules or statement.Yet,, can obtain logic rules simply by observing for three-dimensional situation discussed herein.The border is judged that-1 is transformed into 0, logic rules can be formed:

_K-2BE+A equation 20

Here, the AND operation of " " presentation logic, and+the presentation logic inclusive-OR operation.

Fig. 6 is the block diagram of describing according to the 3D-SSD detector 214 of one aspect of the present invention.Detector 214 comprises delay operator 216 and 218, multiplier 220, add circuit 222,224 and 226, dispenser 228,230,234, "AND" circuit 236 and OR circuit 238.As described in Figure 6, with y _kOffer delay operator 216, and this operator 216 provides y in its output place _K-1This also is provided to and postpones operator 218, provides y by postponing operator 218 in its output place _K-2Multiplier 220 is imported 244 places at it and is received f ₁Add circuit 222 receives offset value delta E at an one input 246 places, and receives y at its two other input end _kAnd y _K-2Adder 224 receives the output 250 and the y of multiplier 220 at two other input with an one input 248 offset value delta B of place _K-2Add circuit 226 receives offset value delta A at its first input, 252 places, and receives from the output 250 of multiplier 220 and the y that comes self-dalay operator 218 in its other input _K-2Add circuit 222,224 and 226 output are provided to dispenser 228,230 and 234 respectively.Dispenser 228,230 and 234 output 229,231 and 235 are provided to circuit 236 and 238 as shown in the figure.The output 256 of circuit 238 provides _K-2So detector 214 uses the multiplexer of a multiplier, three dispensers, three adders and three two inputs.Similarly the 3D-110 detector can be realized with the multiplexer of three dispensers, three adders and two inputs.

In the superincumbent discussion, detector 214 has utilized such advantage to constitute, that is, in each time interval, only occur from one in the

symbol

2 or 5 of table 1 in the signal space graphical diagram.This is because the MTR=2 sign indicating number has removed symbol in two symbols in all time.

Yet, also can limit and remove the main error event of mentioning with reference to Fig. 5-1 and 5-2 with time dependent conversion operations.Such restriction makes three and also only be that they can begin in the preset time interval.In one embodiment, time dependent conversion operations restriction makes three potential energies enough only begin in (that is, odd number or the even number) time interval of being separated by.Such loose restriction makes it possible to develop the coding with each speed.So the employing time changes the MTR sign indicating number, two

symbols

2 and 5 can appear in signal graph in alternate time interval.In order to constitute, must make amendment, so that adapt to the variation of encoding in limiting according to 3D detector of the present invention.

Changing the coding of sign indicating number restriction and the required modification of coded data in order understand to detect better according to having the time, is 2 FDTS/DF tree with reference to the degree of depth, is appreciated that according to signal space detector of the present invention.Fig. 7-1 has described a kind of like this tree 280, and here, tree has the root in odd number time interval k-3 (also representing with label 282) beginning.Fig. 7-2 has described a kind of like this root of locating to begin at even number time interval k-3 (also being labeled as 286) that has.Tree 280 and 284 is all got _K-3=+1.

Under the situation of not losing versatility, this discussion is only allowing three to go under the hypothesis that begins in the even number time interval.Depict although set 280 and 284 root _K-3Value, but that from left to right describe along the branch that tree carries out later on is the value a of sampling _K-2, a _K-1, a _kAnd a _K+1Corresponding time interval is to draw along the bottom of each tree, and provides with label 288,290,292 and 294 in Fig. 7-1, and provides with label 296,298,300 and 302 in Fig. 7-2.

Check that setting 280 and 284 can see, because the paths in path 2 or the path 5 has been violated the coding restriction, so wherein one is not allowed to.For example, in Fig. 7-1, path 5 can be fallen from hedge clipper, and this is because it is given in the three bit code types (+1 ,-1 ,+1 ,-1) that the odd number time interval begins.So in the place of root corresponding to the odd number time interval, this situation is identical with MTR=2 in the previously described detector.On the other hand, shown in Fig. 7-2,, allow two

branches

2 and 5 in the place (and allowing three places that begin at even number time interval place) of root corresponding to the even number time interval.

In order to realize having the coding gain that the time changes the FDTS/DF (2) of MTR sign indicating number, can remove problematic path at odd number time place, and the even number time place recover.Yet

path

2 and 5 appearance have increased selects tree 280 or 284 that the chance of problem part is arranged.In fact, along with the increase of user density, these mistakes begin to become big like this, and make them eliminate the code rate benefit of time variation MTR sign indicating number.

So according to one aspect of the present invention, a step has been extended by (rather than time interval k)

top set

2 and 5 in the time.Extending in like this is labeled as 2A, 2B, 5A and 5B among Fig. 7-1 and the 7-2, and also represents with label 304,306,308,310,312,314,316 and 318.Shown in Fig. 7-1,

path

2 and 5 extension can not influence the pruning of branch.Path 2 still is allowed to, and path 5 still is not allowed to.Yet in Fig. 7-2, the pruning of an extra time interval permission to the 2B of branch extended in the path.In other words, the 2A of branch remains in Fig. 7-2 and to be allowed to, this be because its not time-to-violation change the restriction of MTR sign indicating number.Yet the 2B of branch but violates the coding restriction, because its represents three that begin at the odd number time interval.Similarly, the intelligent a plurality of 5B of branch of Fig. 7-2 are allowed to, and the 5A of branch can be removed.

Among Fig. 7-2, after pruning with all the other symbols of path 2A and path 5B representative corresponding to form be+/-error event of (2 ,-2,2,2).So these two intersymbol spacings should be obviously greater than the minimum euclid distance of encoding.

In one aspect of the invention, three-dimensional/four-dimensional signal space detector (3D/4D SSD) is to realize under the sampling of ISI item after accepting to have three cursors.Detector provides three-dimensional and detects and four-dimensional the detection.In three-dimensional detected, detector was selected data value by the position of determining sampling vector in the three-dimensional signal space.In the four-dimension detected, detector used the position of sampling vector in the 4-coordinate signal space to come the specified data value.

3D/4D SSD adopts with the work of time variation MTR sign indicating number coded data good.When employing has for the odd number time interval that MTR is restricted to 2 MTR sign indicating number and MTR is restricted to 3 for the even number time interval, adopt three-dimensional detection system at the odd number time interval, and, adopt four-dimensional detection system at the even number time interval.

The combination of the most handy sampling by following general sampling equation definition of the sampling vector that uses among the 3D/4D SSD constitutes:

y _k=a _k+ f ₁a _K-1+ f ₂a _K-2+ f ₃a _K-3Equation 30

y _K-1=a _K-1+ f ₁a _K-2+ f ₂a _K-3+ f ₃ _K-4Equation 31

y _K-2=a _K-2+ f ₁a _K-3+ f ₂ _K-4+ f ₃ _K-5Equation 32

y _K-3=a _K-3+ f ₁ _K-4+ f ₂ _K-5+ f ₃ _K-6Equation 33

Here, y _K-3Provide current sampling, to detector _K-xBe the data value of (k-x) individual detection, and a _K-xBe (k-x) individual input value, and detected current input value is a _K-3Input value.

So in the three-dimensional portion of 3D/4D SSD, sampling vector is based on y _K-1, y _K-2And y _K-3Combination, and in four-dimensional part, sampling vector is based on y _K-1, y _K-2, y _K-3And y _K-4Combination.

When pure three-dimensional detected, the position of three-dimensional sampling vector was determined in by following three defined three dimensions of axle:

Y ' _K-1=a _K-1+ f ₁a _K-2+ f ₂a _K-3Equation 34

Y " _K-2=a _K-2+ f ₁a _K-3Equation 35

Y _K-3=a _K-3Equation 36

Notice that each in three axles is to form by removing at least one contribution to each input value of working of taking a sample substantially.Adopt above-mentioned basic sampling equation 30-33, by seeing this point according to sampling definition axle.So the definition of axle just becomes:

Y ' _K-1=y _K-1-f ₃ _K-4Equation 37

Y " _K-2=y _K-2-f ₂ _K-4-f ₃ _K-5Equation 38

Y _K-3=y _K-3-f ₁ _K-4-f ₂ _K-5-f ₃ _K-6Equation 39

As with other embodiments of the invention in, 3D/4D SSD determines odd number time interval data value with the boundary plane in the three dimensional signal space.Boundary plane is with the similar mode of equation 5-19 above and definite obtain following four location identifier:

A:sgn (y _K-3+ f ₁y _K-2+ Δ A) equation 40

B:sgn (y _K-3+ f ₁y _K-2+ Δ B) equation 41

C:sgn (y _K-3-y _K-1+ Δ C) equation 42

D:sgn (y _K-3-y _K-2+ Δ D) equation 43

Here, sgn (statement formula) provides the symbol of statement formula, and value Δ A, Δ B, Δ C and Δ D are the deviants that is provided by following formula:

Δ A=(f ₁-f ₁f ₂ _K-4-(f ₂+ f ₁f ₃) _K-5-f ₃ _K-6-f ₁Equation 44

Δ B=(f ₁-f ₁f ₂ _K-4-(f ₂+ f ₁f ₃) _K-5-f ₃ _K-6+ f ₁Equation 45

Δ C=-(f ₁-f ₃) _K-4-f ₂ _K-5-f ₃ _K-6-1 equation 46

Δ D=-(f ₁-f ₃) _K-4-f ₂ _K-5-f ₃ _K-6+ 1 equation 47

Here, work as _K-4Be-1 and+1 o'clock, adopt plane C and D respectively.Be transformed into 0 with-1 in equation 40-43, detector output provides detector value according to following formula _K-3:

_K-3=A+BC works as _K-4=-1 o'clock, equation 48

_K-3=A+BD works as _K-4=+1 o'clock, equation 49

Here, " " represents the logical operation, and "+" represents the logical "or" operation.

When attempting to detect data value in an even number time interval, 3D/4D SSD determines the position of four-dimensional sampling vector in the 4-coordinate signal space.As mentioned above, the four-dimensional sampling vector that uses between four-dimensional detection period is based on y _k, y _K-1, y _K-2And y _K-3Combination, and they are described by above-mentioned equation 30-33.Between four-dimensional detection period, the position that this four-dimension sampling vector is vowed is to determine in the 4-coordinate space by following four axles definition:

y _k=a _k+ f ₁a _K-1+ f ₂a _K-2+ f ₃a _K-3Equation 50

Y ' _K-1=a _K-1+ f ₁a _K-2+ f ₂a _K-3Equation 51

Y " _K-2=a _K-2+ f ₁a _K-3Equation 52

Y _K-3=a _K-3Equation 53

In this 4-coordinate signal space, the position of four-dimensional sampling vector is compared with the position of the boundary plane that will separate two symbols corresponding to the path 2A of Fig. 7-2 with 5B.

4-coordinate signal space (y at 3D/4D SSD _K-3, y " _K-2, y ' _K-1, y ' _k) in, sampling 2A and 5B lay respectively at (1 ,-1+f ₁, 1-f ₁+ f ₂, 1+f ₁-f ₂+ f ₃) and (1,1-f ₁,-1+f ₁-f ₂,-1-f ₁+ f ₂-f ₃) locate.In four coordinates, coordinate y _K-3And y _kMaximum to the distance contribution that sampling 2A conciliates between 5.Adopt above-mentioned shadow casting technique, the plane between 2A and the 5B is described by following formula:

(y _k-3-1) ²+(y _k-(1+f ₁-f ₂+f ₃)) ²

=(y _K-3+ 1) ²+ (y _k-(1-f ₁+ f ₂-f ₃)) ²Equation 54

This equation simplification becomes:

Y _K-3+ (1+f ₁-f ₂+ f ₃) y _k=0 equation 55

With above-mentioned equation 39 replacement y _K-3, equation 55 becomes:

y _K-3+ (1+f ₁-f ₂+ f ₃) y _k-f ₁ _K-4-f ₂ _K-5-f ₃ _K-6=0 equation 56

Adopt above-mentioned label, so location identifier P just is defined as:

P:sgn (y _K-3+ (1+f ₁-f ₂+ f ₃) y _K-1+ Δ P) equation 57

Here, Δ P is defined by following formula:

Δ P=-f ₁ _K-4-f ₂ _K-5-f _s _K-6Equation 58

Since two symbol 2A and 5B corresponding to form+/-error event of (2 ,-2,2,2), so the distance between two symbols should be significantly greater than the minimum Euclideam distance of encoding.So equation 57 can further be simplified, and performance that can the appreciable impact detector, and obtain:

P:sgn (y _K-3+ y _k+ Δ P) equation 59

In the four-dimension detected, location identifier A, B, C and the D of the equation 40-43 that uses in three-dimensional the detection remained valid.Adopt the location identifier P of these location identifiers and equation 59, the four-dimensional logic detection equation in the even number time interval becomes:

_K-3=A+BC+BDF equation 60

Here, " " represents the logical operation, and "+" represents the logical "or" operation, and A, B, C, D and P comprise 0 to-1 mapping in case of necessity.

Notice that neither one depends on another station location marker symbol in the location identifier.In other words, each identifier determine with another identifier irrelevant.It is also noted that the form of the four-dimensional logic statement formula of equation 60 is the values that do not depend on location identifier.

In an embodiment of the present invention, 3D/4D SSD realizes with the full rate detector among Fig. 8 400.Detector 400 comprises and postpones operator 402,404 and 406, multiplier 408, add circuit 410,412,414,416 and 418, dispenser 420,422,426 and 428, "AND" circuit 452,454 and 456, OR

circuit

458 and 460 and multiplexer 462 and 464.

Postpone operator 402,404 and 406 and be connected in series, and output 403,405 and 407 is provided respectively.Postpone operator 402 and receive y in its input _kThereby the delay operator 402,404 of series connection and 406 provides y at each output 403,405 and 407 places _K-1, y _K-2, and y _K-3

Multiplier 408 receives f in its input ₁And y _K-2, and produce the product of these two values in its output place, and this output links to each other with 418 with add circuit 416.

Except the output that receives multiplier 408, add circuit 418 also receives y _K-3With Δ A.Add circuit 418 produces the output offer dispenser 428 with its input addition, when producing 1 with value dispenser more than or equal to 0 time, and if value less than 0 then produce 0.Add circuit 418 is carried out equation 40 described functions with dispenser 428.

The output and the y of the multiplier 408 that add circuit 416 receives _kWith Δ B.Add circuit 416 with its input value and offer dispenser 426, the working method of this dispenser is similar to dispenser 428.Add circuit 416 is carried out by equation 41 described functions with dispenser 426.

In the

add circuit

410 and 412 each receives y _K-1And y _K-3In addition, add

circuit

410 and 412 receives Δ C and Δ D respectively.Add circuit 410 is from y _K-3In deduct y _K-1, add Δ C, obtain offering the output of dispenser 420, and the working method of dispenser 420 is similar to dispenser 426 and 428.Add circuit 410 and dispenser 420 are carried out the function of equation 42 together.Add circuit 412 is from y _K-3In deduct y _K-1, add Δ D, obtain offering the output of dispenser 422, and the working method of dispenser 422 is similar to dispenser 426 and 428.Add circuit 412 and dispenser 422 are carried out the function of equation 43 together.

Add circuit 414 receives y _k, y _K-3With Δ P, and with they and offer dispenser 424, and the working method of dispenser 424 is similar to dispenser 426.Add circuit 414 and dispenser 424 are carried out the function of equation 59 together.

The detection of odd bits data value in the time is by AND gate circuit 452, OR-circuit 458 and multiplexer 462 decisions, and these circuit are carried out the logic of equation 48 and 49 jointly.According to _K-4Value, multiplexer 462 transmits dispensers 420 and represents the output of location identifier C or the output that dispenser 422 is represented location identifier D.Specifically, work as _K-4Be 0 o'clock, transmit the output of dispenser 420, and work as _K-4Be 1 o'clock, transmit the output of dispenser 422.

The output of multiplexer 462 is provided to AND gate circuit 452 with the output of dispenser 426, represents location identifier B.AND gate circuit 452 is to these input value actuating logic AND-operations, and an output is offered OR-circuit 458, and this OR-circuit also receives the output that dispenser 428 is represented station location marker symbol A.OR-circuit 458 carries out the logical "or" computing to these two input values, and its output is offered multiplexer 464, if detected currency is that then multiplexer 464 provides output valve in not allowing three time interval.

AND gate circuit 454 receives the output that dispenser 422,424 and 426 is represented location identifier D, P and B respectively, and provides logical output according to these inputs.AND gate circuit 456 receives the output that dispenser 420 and 426 is represented location identifier C and D respectively, and according to its input, provides logical output.AND

gate circuit

454 and 456 output are received by OR-circuit 460 with the output of dispenser 428, represent location identifier A.OR-circuit 460 if three allow, then produces the output that is transferred out by multiplexer 464, as detected value to its input actuating logic inclusive-OR operation.

In the another kind of embodiment of 3D/4D SSD, the detector of formation is as a half rate detector, can work being twice under the frequency of incoming symbol.A kind of like this block diagram structure of detector is seen shown in the detector 498 among Fig. 9.

Detector 498 has two to receive y respectively _kAnd y _K-1Input 500 and 502.Two time cycles of signal of two

delay circuits

504 and 506 time-

delay inputs

500 and 502 produce y respectively on circuit 508 and 510 _K-2And y _K-1

Circuit 508 links to each other with even number time cycle circuit 512 with 510, and it comprises multiplier 540, add circuit 514,516,518,520 and 522, dispenser 524,526,528,530 and 532, AND

circuit

534 and 536 and OR circuit 538.Even number time cycle circuit 512 with Fig. 8 in the detector portion similar mode relevant with the detection of even number time cycle data value work.Therefore, AND circuit 534 with 536 and the AND circuit 454 of OR circuit 538 and

detector

400 and 456 and OR circuit 460 carry out identical logical operation.The output of even number time cycle circuit 512 is detected value _K-4

Detector 498 among Fig. 9 also comprises two odd number time cycle circuit 550 and 552, and they carry out the function of equation 49 and 48 respectively.Specifically, odd number time cycle circuit 550 comprises add circuit 554,556 and 558, dispenser 560,562 and 564, AND circuit 566 and OR circuit 568, and odd number time cycle circuit 552 comprises add circuit 570,572 and 574, dispenser 576,578 and 580, AND circuit 582 and OR circuit 584.

Add circuit 570,572,554 and 556 is respectively with y _K-2Be added to the y that multiplier 590 produces _K-1And f ₁Product and Δ A ₀, Δ B ₀, Δ A ₁With Δ B ₁Add circuit 574 and 558 is respectively from y _K-2With Δ C ₀With Δ D ₁And in deduct y _kΔ A ₀, Δ B ₀With Δ C ₀Equal the value of equation 44,45 and 46 respectively.And _K-4Equal 0.Δ A ₁, Δ B ₁With Δ D ₁Equal the value of equation 44,45 and 47 respectively.And _K-4 Equal 1.

Add circuit 570,572,574,554,556 and 558 output are provided to dispenser 576,578,580,560,562 and 564 respectively.Each dispenser is 0 or greater than 0 o'clock in input value, produces one+1, and in their input value less than 0 o'clock, then produce 0.

Dispenser

578 and 580 output are provided to AND circuit 582, to two input actuating logics and function.The output of AND circuit 582 is provided to OR circuit 584 with the output of dispenser 576.584 pairs two of OR circuit input actuating logic exclusive disjunction produces the possible detection corresponding with equation 48 and exports.

Dispenser 562 and 564 output are provided to AND circuit 566, carry out the logical AND function for two inputs.The output of AND circuit 566 is provided to OR circuit 568 with the output of dispenser 560.568 pairs two of OR circuit input actuating logic exclusive disjunction produces the possible detection corresponding with equation 49 and exports.

So odd number time cycle circuit 552 and 550 is got respectively _K-4Equal 0 and 1, and calculate possible detected value according to this hypothesis.This hypothesis is necessary in detector 498, and this is because _K-3Be to have determined _K-4Calculate before.In case _K-4After having determined by even number time cycle circuit 512, _K-4Value be used for selecting _K-3The latter is to use _K-4Correct hypothesis calculate.This selection is carried out by multiplexer 592, and this multiplexer 592 is worked as _K-4Be to send at 0 o'clock from odd number time cycle circuit 552 _K-3Value, and work as _K-4Be to send at 1 o'clock from odd number time cycle circuit 550 _K-3Value.

So, can see that the present invention is used for the signal space detector of MTR-encoding channel.Because channel response is not forced to limit, so detector can be used in widely in the user density scope.Simultaneously, signal space detector adopts MTR=2 restriction and time variation MTR sign indicating number to realize according to the present invention.Adopt the MTR=2 sign indicating number, detector is providing significant gain on the 3D-110 detector under the lower user density.Adopt the time of higher rate to change the MTR sign indicating number, particularly under higher density, can further improve performance.

The invention provides the detector in a kind of disc driver 110, it comprises and being used at the first signal space y _K-3, y " _K-2, y ' _K-1In determine sampling vector y _K-3, y _K-2, y _K-1First detector portion 462,452,458 of position.Detector 400 also comprises and being used at secondary signal space y _K-3, y " _K-2, y ' _K-1, y _kIn determine the second sampling vector y _K-3, y _K-2, y _K-1y _kSecond detector portion 454,456,460,464 of position.This determines with logical expression, equation 60 a plurality of location pointers (indicator) A, B, C, D and P to be combined.Each location pointer provides the

position

0 or 1 with respect to second sampling vector of each border surface A, B, C, D or P.Logical expression and location identifier are the values that is independent of other location identifiers.

The present invention also is a kind of method.This method comprises determines two location identifier A, B, C and D at least, and these location identifiers provide the first signal space y _K-3, y " _K-2, y ' _K-1In, with respect to each border A, B, C and D sampling vector y _K-3, y _K-2, y _K-1The position.According to location identifier, determine the first data value subsequently _K-3As each additional position identifier indication secondary signal space y _K-3, y " _K-2, y ' _K-1, y _kIn with respect to the second sampling vector y of each border surface A, B, C, D and P _K-3, y " _K-2, y ' _K-1, y _kThe position time, at least two additional position identifier A, B, C, D and P are determined.Subsequently, by the additional position group identifier being determined the second data value altogether with judgement equation 60 _K-3The form of judgement equation 60 is the values that are independent of the additional position identifier.

The present invention can also be as the signal space detector of carrying out above-mentioned steps.

Be to be understood that, although when describing the 26S Proteasome Structure and Function of the various embodiment of the present invention, described various feature of the present invention and the advantage of various embodiment in the above description, but these descriptions only are descriptive, various details can have change, particularly in principle of the present invention to the change of modular construction and arrangement, the degree of change can be in by the wideest scope that claims limited.For example, particular element can change according to specific local acknowledgement's target and MTR sign indicating number, basic simultaneously maintenance identical functions, and do not depart from scope and spirit of the present invention.

In addition, although preferred embodiment as described herein at be the signal space detector of disk drive system, but those skilled in the art are appreciated that, principle of the present invention also can be applied to other system, as tape drive, CD drive or magnetic-CD-ROM driver system, and do not depart from scope and spirit of the present invention.

Claims

1. the detector in the disc driver, described detector adopts the sampling vector that is formed by a plurality of relevant data samplings that separate temporarily to detect data value, it is characterized in that described detector comprises:

First detector portion (462,452,458) is used for detecting first data value by the position of determining first sampling vector in first signal space; And

Second detector portion (454,456,460), be used for detecting second data value by the position of determining second sampling vector in the secondary signal space, describedly determine to adopt logical expression to make up a plurality of location pointers to make, each location pointer provides the position with respect to second sampling vector of each border surface, and the value of described logical expression and location pointer is the value that is independent of other location pointers.

2. detector as claimed in claim 1 is characterized in that, described first signal space has (N-1) individual coordinate, and there is N coordinate in described secondary signal space.

3. detector as claimed in claim 1, it is characterized in that, described data sampling is based on input value, and described input value is to adopt the time that changes between the restriction of first on a plurality of time intervals and second restriction to change maximum conversion operation (run) restriction to encode.

4. detector as claimed in claim 3 is characterized in that, described first detector detection is corresponding to the data value of the input value of encoding according to first restriction, and described second detector detects the data value corresponding to the input value of encoding according to second restriction.

5. detector as claimed in claim 1, it is characterized in that, described first detector portion is determined the position of described first sampling vector with a plurality of location pointers, and each location pointer provides the position of described first sampling vector with respect to each relevant border surface.

6. detector as claimed in claim 5 is characterized in that, at least one border surface is used by described first detector portion and described second detector portion.

7. detector as claimed in claim 6 is characterized in that, all border surfaces that described first detector portion is used are used by the described second detector parts branch, and wherein, described second detector portion also adopts the another one border surface.

8. detector as claimed in claim 7 is characterized in that, is partly to determine according to the secondary signal space in described first signal space with the location pointer of described other boundary-related.

9. detector as claimed in claim 1, it is characterized in that, described location pointer is in first value and second value, and the described sampling vector of described first value representation is in first side on relevant border surface, and the described sampling vector of described second value representation is in second side of border surface.

10. the sampling read signal that reads of the disk of a basis from disc driver detects the method for data value, and the data sampling that provides in a plurality of time intervals is provided described sampling read signal, it is characterized in that, described method comprises following step:

(a) determine at least two location identifiers, each position identifier list shows the position with respect to each border surface sampling vector in first signal space;

(b) determine first data value according to described location identifier;

(c) determine at least two other location identifiers, each other location identifier is represented the position of second sampling vector with respect to each border surface in the secondary signal space; And

(d) adopt a judgement equation to determine that by making up described other location identifier second data value, the form of described judgement equation are the values that is independent of described other location identifier.

11. method as claimed in claim 10 is characterized in that, the value of described each other location identifier is separate.

12. method as claimed in claim 10 is characterized in that, described secondary signal space comprises four coordinates, and described first signal space comprises three coordinates.

13. method as claimed in claim 12 is characterized in that, described sampling vector comprises three data samplings that temporarily separate, and described second sampling vector comprises four data samplings that temporarily separate.

14. method as claimed in claim 13 is characterized in that, four coordinates in described secondary signal space comprise (a _k+ f ₁a _K-1+ f ₂a _K-2+ f ₃a _K-3), (a _K-1+ f ₁a _K-2+ f ₂a _K-3), (a _K-2+ f ₁a _K-3) and (a _K-3), here, a _kBe k input value, and f ₁, f ₂And f ₃It is proportionality constant.

15. method as claimed in claim 14 is characterized in that, three coordinates of described first signal space comprise (a _K-1+ f ₁a _K-2+ f ₂a _K-3), (a _K-2+ f ₁a _K-3) and (a _K-3).

16. method as claimed in claim 15 is characterized in that, described second sampling vector comprises four samplings, comprises (a respectively _k+ f ₁a _K-1+ f ₂a _K-2+ f ₃a _K-3), (a _K-1+ f ₁a _K-2+ f ₂a _K-3+ f ₃ _K4), (a _K-2+ f ₁a _K-3+ f ₂ _K-4+ f ₃ _K-5) and (a _K-3+ f ₁ _K-4+ f ₂ _K-5+ f ₃ _K-6).

17. method as claimed in claim 10 is characterized in that, five border surfaces are arranged in described secondary signal space.

18. method as claimed in claim 10, it is characterized in that, described read signal is based on input value, and described input value is to have adopted in the time that the cycle changes between first restriction and second restriction on a plurality of time intervals to change maximum conversion operation restriction coding.

19. method as claimed in claim 10 is characterized in that, described step (a) and (c) be simultaneous.