CN100474782C - Method and apparatus for coding information and decoding coded information, recording medium and method of fabricating the same - Google Patents

Abstract

In the encoding device and method of the present invention, m-bit information words are converted into n-bit code words, so that the encoding rate m/n is greater than 2/3. The n-bit codeword is divided into the first and second categories, and is divided into the first and second encoding states, so that if the previous m-bit information word is converted into an n-bit codeword of the first category, the m-bit The information word is converted into an n-bit code word of the first or second type, and if the previous m-bit information word is converted into an n-bit code word of the second type, the m-bit information word is converted into an n-bit code word of the first type . In one embodiment, the n-bit codewords of the first type end with 0, the n-bit codewords of the second type end with 1, the n-bit codewords of the first type start with 0, and the n-bit codewords of the second type Start with 0 or 1. In addition, in this embodiment, the n-bit code word satisfies the dk constraint to (1, k), so that there is at least one 0 and at most k 0s between consecutive 1s.

Description

Method and device for encoding and decoding information, recording medium and production method thereof

technical field

The present invention relates to information coding, in particular to a method and device for information coding with enhanced information density. The invention also relates to the production of modulated signals from coded information, the production of recording media from coded information, and the recording media themselves. The invention also relates to methods and devices for decoding encoded information and decoding encoded information from a modulated signal and/or a recording medium.

Background technique

When data is transmitted over a transmission line or recorded on a recording medium such as a magnetic disk, optical disk, or magneto-optical disk, the data is modulated into a code that matches the transmission line or recording medium before transmission or recording .

Run-length limited codes, commonly referred to as (d,k) codes, have been widely and successfully applied to modern magnetic and optical recording systems. K.A. Schouhamor Immink in the book "Codes for Mass Data Storage Systems" (ISBN 90-74249-23-X, 1999) describes such codes and means for implementing them. Run-length limited codes are an extension of earlier non-return-to-zero recording encodings, in which a "0" recorded by binary is represented by no (magnetic flux) change on the recording medium, and a binary "1" is represented by a change in flux from the recorded flux. Direction to the opposite direction conversion is represented.

In (d, k) encoding, the above-mentioned recording rules are still valid, but with additional constraints, that is, at least d "0"s must be recorded between consecutive "1s", and at most k "0". The first constraint is used to eliminate intersymbol interference caused by pulse crowding of regenerative transitions when consecutively recording a series of '1's. The second constraint is used to ensure that the clock is recovered from the regenerated data by "locking" the phase locked loop to the regenerated transition. If there is an excessively long string of consecutive '0's without intervening '1's, the clock that regenerates the PLL will become out of sync. For example, in (1,7) encoding, there is at least one "0" between recorded "1s", and no more than 7 consecutive "0s" between recorded "1s".

Through a modulo-2 integration operation, a series of encoded bits is converted into a corresponding modulated signal formed of bits with high or low signal value. In the modulated signal, a "1" bit is represented by a change in signal value from high to low or vice versa, and a "0" bit is used to represent no change in the modulated signal.

The information transmission efficiency of this type of encoding is generally expressed as a ratio (m/n) of the number of bits in the information word (m) to the number of bits (n) in the code word. The maximum theoretical ratio of codes for a given value of d and k is called the Shannon capacity. Figure 1 tabularly shows the Shannon channel capacity C(d, k) for different k when d=1. As shown in the figure, for a(1,7) coding, the Shannon channel capacity, C(1,7) has a value of 0.67929. What it means is that the (1,7) code has no ratio greater than 0.67929. The actual implementation of the encoding requires the ratio to be a rational fraction, and for the above (1,7) encoding, the ratio is 2/3. The ratio of 2/3 is slightly less than the Shannon channel capacity of 0.67929, so this encoding is an efficient encoding. To achieve a ratio of 2/3, transform 2 unconstrained data bits into 3 constrained coded bits.

(1,7) encoding with a rate of 2/3 and means for implementing the associated encoder and decoder are well known in the art. U.S. Patent No. 4,413,251 entitled "Method and Apparatus for Generating A Noiseless Sliding Block Code for a (1, 7) Channel with Rate 2/3" proposed by Adler et al. discloses an encoder, which is a A finite state machine with 5 internal states. US Patent No. 4,488,142 entitled "Appratus for Encoding Unconstrained Data onto a (1, 7) Format with Rate 2/3" by Franaszek discloses an encoder with 8 internal states.

However, there is a need for more efficient encodings that, for example, increase the information density on recording media or transmission lines.

Contents of the invention

According to the conversion method and apparatus of the present invention, m-bit information words are converted into n-bit code words at a rate greater than 2/3. Therefore, the same amount of information can be recorded in a smaller space, increasing the information density.

In the present invention, the n-bit code word is divided into the first type and the second type, and is divided into the first type and the second coding state, thereby, if the previous m-bit information word is converted into the n-bit code of the first type word, convert the m-bit information word into the first or second type of n-bit code word, and if the previous m-bit information word is converted into the second type of n-bit code word, then convert the m-bit information word into the first A kind of n-bit codeword. In one embodiment, the n-bit codewords of the first type end with 0, the n-bit codewords of the second type end with 1, the n-bit codewords of the first type start with 0, and the n-bit codewords of the second type Start with 0 or 1. Also, according to the embodiment of the present invention, the n-bit code word satisfies the dk constraint to (1, k), so that at least one 0 and at most k 0s are filled between consecutive 1s.

In another embodiment of the present invention, the encoding device and method according to the present invention are used to record information on a recording medium, and the recording medium is produced according to the present invention.

In other embodiments of the invention, the encoding device and method according to the invention are further used for transmitting information.

According to the decoding method and device of the present invention, the n-bit code word created according to the encoding method and device is decoded into an m-bit information word. Decoding includes determining the state of the next n-bit code word, and based on the determined state, converting the current n-bit code word into an m-bit information word.

In other embodiments of the invention, information is reproduced from a recording medium using decoding apparatus and methods according to the invention.

In other embodiments of the invention, the encoding device and method according to the invention are also used for receiving information transmitted over a medium.

Description of drawings

From the following detailed description of the present invention, combined with the accompanying drawings, the present invention can be more fully understood. The accompanying drawings are for illustrative purposes only, wherein the corresponding parts in different drawings use the same reference numerals. In the attached picture:

What Fig. 1 shows is the list of Shannon channel capacity C(d, k) to different k when d=1;

Figure 2 shows an example of how codewords in different packets are assigned to different states in the first embodiment;

Figure 3 shows an embodiment of an encoding device according to the invention;

What Fig. 4A-4H shows is the complete conversion table when converting 9 information words into 13 code words according to the first embodiment;

What Fig. 5 shows is to use the conversion table of Fig. 4A-4H to convert a series of information words into the conversion process of a series of code words;

Figure 6 shows an embodiment of a recording device according to the present invention;

Figure 7 shows a recording medium and a modulated signal according to the present invention;

Figure 8 shows a transmission device according to the invention;

Figure 9 shows a decoding device according to the present invention;

Figure 10 shows a regeneration device according to the present invention;

Figure 11 shows a receiving device according to the present invention;

Figure 12 shows an example of how codewords in different groups are assigned to different states in the second embodiment;

What Fig. 13A-13C shows is when converting 9-bit information words into 13-bit code words according to the second embodiment, the beginning, middle and end of the conversion table;

What Fig. 14 shows is how in the third embodiment code words in different groups are assigned to the example of different states;

What Fig. 15A-15C shows is when 11 information words are converted into 16 code words according to the third embodiment, the beginning, the middle and the end part of conversion table;

What Fig. 16 shows is how in the fourth embodiment codewords in different groups are allocated to the example of different state;

17A-17C show the beginning, middle and end of the conversion table when converting 13-bit information words into 19-bit code words according to the fourth embodiment.

Detailed Description of Preferred Embodiments

The general encoding method according to the present invention will be described below first through a first specific embodiment of the encoding method. Next, a general decoding method according to the present invention will be described after the contents of the first embodiment. Different devices according to the invention are then described. In particular, an encoding device, recording device, transmission device, decoding device, reproduction device, and reception device according to the present invention will be described. After that, an additional encoding embodiment according to the present invention will be described.

encoding method

According to the invention, m-bit information words are converted into n-bit code words at a rate greater than 2/3. The code words are divided into first and second classes, where the first class includes code words ending in "0" and the second class includes code words ending in "1". As a result, the code words of the first class are divided into two groups E00 and E10, and the code words of the second class are divided into two groups E01 and E11. Codeword group E00 contains codewords starting with "0" and ending with "0", codeword group E01 contains codewords starting with "0" and ending with "1", codeword group E10 contains codewords starting with "1" And codewords ending with "0", the codeword group E11 contains codewords starting with "1" and ending with "1".

The code words are also divided into at least one state of the first type and at least one state of the second type. The first type of state includes only code words starting with "0", while the second type of state includes code words starting with "0" or "1".

Encoding method according to the first embodiment

In a first preferred embodiment of the invention, 9-bit information words are converted into 13-bit code words. The code word satisfies the (1, k) constraint, and is divided into 3 states of the first type and 2 states of the second type (5 states in total). In order to reduce the k-constraint, the three code words "0000000000000", "0000000000001", and "0000000000010" are forbidden in the coding table. The enumeration of code words shows that there are 231 code words in group E00, 144 code words in group E10, 143 code words in group E01 and 89 code words in group E11.

To encode, each 13-bit codeword in each state is associated with an encoded state direction. State direction refers to the next state from which to choose a codeword during encoding. State directions are assigned to codewords such that codewords ending in "0" (i.e. codewords in packets E10 and E00) have an associated state direction indicating any one of r = 5 states, whereas codewords ending in "1" The codewords of (ie, the codewords in packets E01 and E11 ) have an associated state direction indicating only one of the first states. This ensures that the constraint of d=1 can be satisfied, ie, after a codeword ends with a "1", the next codeword will start with a "0".

Furthermore, as will be explained in more detail below, while the same codeword can be assigned to different information words in the same state, different states cannot contain the same codeword. In particular, the codewords in packets E10 and E00 can be allocated 5 times in one state to different information words, while the codewords in packets E11 and E01 can be allocated 3 times in one state to different information words. Since there are 231 codewords in group E00 and 144 codewords in group E10, there are 1875 (5×(231+144)) “codeword-state direction” combinations for the codewords of the first category. There are 143 codewords in group E01 and 89 codewords in group E11, so there are 696 (3×(143+89)) combinations of “codeword-state direction” for the codewords of the second category. There are 1875+696=2571 combinations of "codeword-state direction" in total.

For an m-bit information word, there are 2 ^m possible information words. Therefore, for 9-bit information words, there are 2 ⁹ =512 information words. Since there are 5 states in this coding embodiment, 5*512=2561 "codeword-state direction" combinations are needed. This leaves 2571-2561=10 remaining combinations.

According to the above constraints, the available codewords in different groups are distributed over the first and second states. Fig. 2 shows an example of how to assign codewords in different packets to different states in this embodiment. As shown in FIG. 2, in this example, states 1, 2, and 3 belong to the first state, while 4 and 5 belong to the second state. Taking packet E00 with a size of 230 as an example, packet E00 has 76 codewords in states 1, 2, and 3, and 1 codeword in states 4 and 5. Taking state 1 as an example, in state 1, the number of "codeword-state direction" combinations is 5*76+3*44=512, which means that 9-bit information words can be allocated. Remember, each codeword of the first category can be assigned any one of five different states as a state direction, and is therefore used 5 times in a state; while each codeword of the second category is only One of the three states of the first type can be assigned to use 3 times in one state.

It can be verified that from any one of the coding states of r=5 shown in FIG. 2, at least 512 information words can be allocated to code words, which is sufficient for arranging 9-bit information words. In the manner described above, any series of 9-bit information words can be individually converted into a series of code words.

Figures 4A-4H show the complete conversion tables for converting 9-bit information words into 13-bit code words according to this embodiment. Included in the transition tables in Figures 4A-4H are the state directions assigned to the respective codewords. In particular, in Figures 4A-4H, the first column shows the decimal representation of the information word in the second column. The third, fifth, seventh, ninth and eleventh columns show the codewords (also called channel bits in the art) assigned to the information words in states 1, 2, 3, 4 and 5, respectively. The fourth, sixth, eighth, tenth and twelfth columns are shown in the third, fifth, seventh, ninth and eleventh columns respectively by the individual numbers 1, 2, 3, 4 and 5 The state direction of the associated codeword.

Referring to Fig. 5, the conversion from the series of information words to the series of code words is further explained. The first column of Figure 5 shows, from top to bottom, the series of consecutive 9-bit information words, and the second column shows the decimal values of these information words in parentheses. The third column "State" is the coded state to be used for information word transitions. The "state" is set when the previous codeword was issued (ie, the state direction of the previous codeword). The fourth column "Codeword" contains the codewords assigned to the information words according to the conversion tables of Figures 4A-H. The fifth column "next state" is the state direction associated with the codeword in the fourth column, also determined according to the transition tables of Figures 4A-H.

The first word in the series of information words shown in the first column in FIG. 5 has a word value of "1" in decimal. When initiating a switch to a series of information words, we assume that the encoding state is 1 (S1). Therefore, according to the setting of code word state 1 in the conversion table, the first word is converted into code word "0000000000100". Meanwhile, since the state direction assigned to the code word "0000000000100" and representing the decimal value 1 in state 1 is state 2, the next state becomes 2 (S2). This indicates that the next information word (decimal value "3") is to be converted using the code word in state 2. Therefore, the next information word whose decimal value is "3" is converted into the code word "0001010001010". In a manner similar to that described above, the information words with decimal values "5", "12" and "19" are converted.

decoding method

Next, with reference to Figs. 4A-4H, the decoding of n-bit code words (13-bit words in this example) received from the recording medium is further explained. For the purpose of description, it is assumed that the successive codeword series received from the recording medium have word values such as "0000000000100", "0001010001010", "0101001001001". From the conversion tables in Figures 4A-4H, it can be seen that the first code word "0000000000100" is assigned to the information words "0", "1", "2", "3" and "4", and the state direction 1, respectively. 2, 3, 4 and 5. The next codeword has the value "0001010001010" and belongs to the set of codewords in state 2. This means that the first codeword "0000000000100" has a state direction with a value of 2. The first code word "0000000000100" with a state direction of value 2 represents an information word with decimal value "1". Therefore, it is determined that the first code word represents the information word "000000001" having the decimal value "1".

Also, the third code word "0101001001001" is a member of state 4. Therefore, in the same manner as above, it is determined that the second code word "0001010001010" represents an information word having a decimal value "3". In the same way, other codewords can be decoded. Note that the current codeword and the next codeword are observed to decode the current codeword into a unique information word.

coding equipment

Figure 3 shows an embodiment of an encoding device 124 according to the invention. The coding device 124 converts the m-bit information word into an n-bit code word, where s bits represent the number of different coding states r. For example, when the number of encoding states r=5, s=3. As indicated above, the encoding device 124 includes a converter 50 for converting (m+s) binary input signals into (n+s) binary output signals. In a preferred embodiment, the converter 50 comprises only a read-only memory (ROM) for storing the conversion table according to at least one embodiment of the present invention and addresses for addressing the conversion table according to m+s binary input signals circuit. However, instead of ROM, converter 50 may include a combinational logic circuit for producing the same results as a conversion table according to at least one preferred embodiment of the present invention.

Among the input terminals of the converter 50, m input terminals are connected to the first bus 51 for receiving m-bit information words. Among the outputs of the converter 50, n outputs are connected to a second bus 52 for transmitting n-bit codewords. In addition, the s input ends are connected to the third bus 53 of s bits for receiving the status word indicating the instant coding status. The status word is transferred by a buffer memory 54 containing, for example, s flip-flops. The buffer memory 54 has an input connected to a fourth bus 55 for receiving a status word to be loaded into the buffer memory 54 as a status word. To transfer the state directions loaded into the buffer memory 54, the s outputs of the converter 50 are used.

The second bus 52 is connected to the parallel input of a parallel-to-serial converter 56, which converts the codeword received via the second bus 52 into a serial bit string. Signal line 57 carries the serial bit string to modulator circuit 58, which converts the bit string into a modulated signal. The modulated signal is then transmitted over bus 60 . Modulator circuit 58 is a well-known circuit for converting binary data into a modulated signal, such as a modulo-2 integrator.

For the purpose of synchronizing the operation of the encoding device, the encoding device includes a clock generation circuit (not shown) of conventional type for generating a clock signal controlling the timing of loading of, for example, parallel/serial converter 58 and buffer memory 54 .

In operation, converter 50 receives an m-bit information word and an s-bit status word from first bus 51 and third bus 53, respectively. The s-bit status word indicates the status in the conversion table to be used when converting the m-bit information word. Thus, from the value of the m-bit information word, the n-bit codeword is determined from the codewords of the state identified by the s-bit status word. Likewise, the state direction associated with the n-bit codeword is determined. The state direction, that is, its value converted to an s-bit binary word; or alternatively the state direction stored in the conversion table as an s-bit binary word. The converter 50 outputs an n-bit codeword on the second bus 52 and an s-bit status direction on the fourth bus 55 . The buffer memory 54 stores the s-bit status direction as a status word, and synchronously transmits the s-bit status word to the converter 50 through the third bus 53 together with the next m-bit information word received by the converter 50 . This synchronization is based on a clock signal generated in any of the above known ways.

The n-bit code word on the second bus 52 is converted into serial data by a parallel/serial converter 56, and then the serial data is converted into a modulated signal by a modulator 58.

The modulated signal can be further processed for recording or transmission.

recording device

FIG. 6 shows a recording device for recording information comprising the encoding device 124 according to the invention shown in FIG. 3 . As shown in FIG. 6, m-bit information is converted into a modulated signal by an encoding device 124. The modulation signal generated by the encoding device 124 is transmitted to the control circuit 123 . The control circuit 123 may be any conventional control circuit for controlling the optical pickup or the laser diode 122 in response to a modulation signal applied to the control circuit 123 so as to record a mark pattern corresponding to the modulation signal on the recording medium 110 .

Fig. 7 shows by way of example a recording medium 110 according to the invention. The recording medium 110 shown is a read only memory (ROM) type optical disc. However, the recording medium of the present invention is not limited to a read only memory (ROM) type optical disc, but may be any type of optical disc such as a write once read many (WORM) optical disc, a random access memory (RAM) optical disc, and the like. Also, the recording medium 110 is not limited to an optical disk, and may be any type of recording medium, such as a magnetic disk, a magneto-optical disk, a memory card, a magnetic tape, and the like.

As shown in FIG. 7 , a recording medium 110 according to one embodiment of the present invention includes information patterns disposed on tracks 111 . In particular, FIG. 7 shows an enlarged view of the magnetic track 111 along the direction 114 of the magnetic track 111 . As shown, the track 111 includes an information pit area 112 and a non-information pit area 113 . Generally, the information pit area 112 and the non-information pit area 113 represent the constant signal area (0 value in the code word) of the modulated signal 115, and the transition between the information pit area and the non-information pit area represents the logic state transition of the modulated signal 115 (value of 1 in the codeword).

As described above, the recording medium 110 can be obtained by first generating a modulated signal and then recording on the recording medium. Alternatively, if the recording medium is an optical disc, the recording medium 110 can also be obtained using well-known mastering and reproduction techniques.

transmission device

FIG. 8 shows a transmission device for transmitting information comprising the encoding device 124 according to the invention shown in FIG. 3 . As shown in FIG. 8, the m-bit information word is converted into a modulated signal by an encoding device 124. Then the transmitter 150 further processes the modulated signal, converts the modulated signal into a transmission form according to the communication system to which the transmitter belongs, and transmits the converted signal through a transmission medium such as air (or space), optical cable, cable, conductor, etc. Modulated signal.

decoding equipment

Figure 9 shows a decoder according to the invention. The decoder performs the reverse process of the converter in Fig. 3, and converts the n-bit code word of the present invention into an m-bit information word. As shown, the decoder 100 includes a first look-up table (LUT) 102 and a second look-up table (LUT) 104 . The first and second look-up tables 102 and 104 store conversion tables needed to create n-bit codewords for decoding. Where K represents time, the first lookup table 102 receives the (K+1)th n-bit codeword, and the second lookup table 104 receives the output of the first lookup table 102 and the Kth n-bit codeword. Thus, the decoder 100 operates as a sliding block decoder. At each block instant the decoder 100 decodes an n-bit code word into an m-bit information word and proceeds to process the next n-bit code word in the serial data (also referred to as the channel bit stream).

In operation, the first LUT 102 determines the state of the (K+1)th codeword from the stored transition table and outputs this state to the second LUT 104. Thus the output of the first LUT 102 is a binary number in the range of 1, 2, ..., r (where r refers to the number of states in the transition table). From the kth codeword, the second LUT 104 determines possible m-bit information words associated with the kth codeword using the stored conversion table, and then uses the state information in the first LUT 102 and the stored conversion table , to determine a particular one of the possible m-bit information words represented by n-bit codewords.

For further explanation purposes only, assume that the n-bit codeword is a 13-bit codeword generated using the conversion tables in Figures 4A-4H. Then, referring to FIG. 5, if the (K+1)th 13-bit code word is "0001010001010", the first LUT 102 determines that the state is state 2. Also, if the Kth 13-bit codeword is "0000000000100", then the second LUT 104 determines that the Kth 13-bit codeword represents a 9-bit message with a decimal index value of 0, 1, 2, 3, or 4 Character. And, since the next state or the state direction of state 2 is provided by the first LUT 102, since the 13-bit code word "0000000000100" associated with the state direction of state 2 represents a 9-bit information word with a decimal value of 1, the second LUT 104 determines that the Kth 13-bit codeword represents a 9-bit information word having a decimal value of 1.

Recycling equipment

FIG. 10 shows a reproducing apparatus including the decoder 100 shown in FIG. 9 according to the present invention. As shown, the reading device includes a conventional type optical pickup 122 for reading a recording medium 110 according to the present invention, which may be any of the recording media previously discussed. The optical pickup 122 generates a modulated analog read signal according to the information pattern on the recording medium 110 . The detection circuit 125 converts this read signal into a binary signal in a form receivable by the decoder 100 in a conventional manner. Decoder 100 decodes this binary signal to obtain m-bit information words.

receiving device

FIG. 11 shows the receiving device including the decoder 100 shown in FIG. 9 according to the present invention. As shown, the receiving device includes a receiver 160 for receiving signals transmitted through a medium such as air (or space), optical cable, electrical cable, conductor, and the like. Receiver 160 converts the received signal into a binary signal in a form receivable by decoder 100 . Decoder 100 decodes this binary signal to obtain m-bit information words.

Encoding method according to the second embodiment

Figure 12 and Figures 13A-13C show another embodiment of the present invention. According to this embodiment, by converting the 9-bit information word into a 13-bit code word, a ratio greater than 2/3 can be achieved; where the number of coding states r is equal to 13, of which 8 coding states are the first coding state, 5 coding states state is the second coded state. At the same time, the codeword satisfies the (1, k) constraint. Fig. 12 corresponds to Fig. 2 of the first embodiment, and shows the classification of code words in each state in the second embodiment.

As mentioned above, codewords ending in "0", i.e. in packets E00 and E10, allow entry to any of the r = 13 states, while codewords ending in "1", i.e. in packet E01 and codewords in E11, only states in the first state (state 1 to state 8) are allowed to be entered.

Thus, the codewords in packets E00 and E10 can be assigned 13 times to different information words, while the codewords in packets E01 and E11 can be assigned 8 times to different information words. Referring to FIG. 12 , packet E00 has 24 codewords in state 1 and packet E01 has 25 codewords in state 1 . So the number of "codeword-state direction" combinations is (13*24)+(8*25)=512, which means that 9-bit information words can be allocated. It can be shown that from any one of the r=13 coding states, at least 512 information words can be allocated to code words, which is sufficient to satisfy 9-bit information words.

Figures 13A-13C show the beginning, middle and end portions of the conversion table of the second embodiment in the same manner as the conversion table of the first embodiment shown in Figures 4A-4H.

Encoding method according to the third embodiment

Figure 14 and Figures 15A-15C show another embodiment of the present invention. According to this embodiment, by converting 11-bit information words into 16-bit code words, a ratio greater than 2/3 is achieved; wherein the number of encoding states r is equal to 13, and 8 encoding states are the first encoding states, and 5 The coded state is the second coded state. At the same time, the codeword satisfies the (1, k) constraint. Fig. 14 corresponds to Fig. 2 of the first embodiment, and shows the classification of code words in each state in the third embodiment. It can be shown that from any one of the r = 13 coding states, at least 2048 information words can be assigned to code words, which is sufficient to satisfy 11-bit information words.

15A-15C show the beginning, middle and end portions of the conversion table of the third embodiment in the same manner as the conversion table of the first embodiment shown in FIGS. 4A-4H.

Encoding method according to the fourth embodiment

Figure 16 and Figures 17A-17C show another embodiment of the present invention. According to this embodiment, by converting the 13-bit information word into a 19-bit code word, a ratio greater than 2/3 is achieved; wherein the number of encoding states r is equal to 5, and the 3 encoding states are the first encoding states, and the 2 encoding states The state is the encoded state of the second type. At the same time, the codeword satisfies the (1, k) constraint. Fig. 16 corresponds to Fig. 2 of the first embodiment, and shows classification of code words in each state in the fourth embodiment. It can be shown that from any one of the r=5 coding states, at least 8192 information words can be assigned to code words, which is sufficient to satisfy 13-bit information words.

17A-17C show the beginning, middle and end portions of the conversion table of the fourth embodiment in the same manner as the conversion table of the first embodiment shown in FIGS. 4A-4H.

Industrial Applicability

As mentioned above, at a ratio greater than 2/3, m-bit information words are converted into n-bit code words. Therefore, the same amount of information can be recorded in a smaller space, and the information density can be increased.

The present invention has been described in detail with reference to preferred embodiments, but it is obvious that various modifications and changes can be made within the spirit and scope of the present invention.

Claims (64)

1. one kind is converted to the method for code word with information word, comprising:

Receive m position information word, m is an integer here;

M position information word is converted to n position code word, here n is the integer greater than m, n position code word is divided into two groupings of the first kind and two groupings of second class, and be divided into first kind of encoding state and second kind of encoding state, first grouping of the first kind comprises the code word that begins and end up with first logical value, second grouping of the first kind comprises with second logical value and beginning and with the code word of first logical value ending, first grouping of second class comprises with first logical value and beginning and with the code word of second logical value ending, second grouping of second class comprises the code word that begins and end up with second logical value; N position code word in first kind of encoding state begins with first logical value, and the n position code word in second kind of encoding state begins with first or second logical value;

If wherein previous m position information word is converted to the n position code word of the first kind, the m position information word of then following is converted to the n position code word of first kind of encoding state or second kind of encoding state, if and previous m position information word is converted to the n position code word of second class, the m position information word of then following be converted to first kind of encoding state n position code word.

2. according to the method for claim 1, wherein this switch process is converted to m position information word the n position code word that satisfies the dk constraint, here d is illustrated in the code word of n position ' 0 ' minimal amount between ' 1 ' continuously, and k is illustrated in the code word of n position ' 0 ' maximum number between ' 1 ' continuously.

3. according to the method for claim 2, wherein m/n is greater than 2/3, and d=1.

4. according to the method for claim 2, d=1 wherein.

5. according to the method for claim 2, wherein n position code word is divided into first kind p encoding state and second kind q encoding state, here, p and q are greater than or equal to 1 integer, and the n position code word that each had in p and the q encoding state is different from the n position code word in other p and q the encoding state.

6. according to the method for claim 5, wherein m/n is greater than 2/3, d=1, p=3 and q=2.

7. according to the method for claim 5, p=3 wherein, and q=2.

8. according to the method for claim 5, wherein p+q equals 5.

9. according to the method for claim 5, wherein m/n is greater than 2/3, d=1, p=8 and q=5.

10. according to the method for claim 5, wherein p=8 and q=5.

11. according to the method for claim 5, wherein p+q equals 13.

12., wherein in the state in p encoding state, have at least a n position code word relevant with p+q m position information word according to the method for claim 5.

13., wherein in the state in q encoding state, have at least a n position code word relevant with p m position information word according to the method for claim 12.

14., wherein in the state in q encoding state, have at least a n position code word relevant with p m position information word according to the method for claim 5.

15. method according to claim 1, wherein n position code word is divided into first kind p encoding state and second kind q encoding state, here, p and q are greater than or equal to 1 integer, and the n position code word that each had in p and q the encoding state is different from the n position code word in other p and q the encoding state.

16. according to the method for claim 15, wherein p+q equals 5.

17. according to the method for claim 15, wherein p+q equals 13.

18., wherein in the state in p encoding state, have at least a n position code word relevant with p+q m position information word according to the method for claim 15.

19., wherein in the state in q encoding state, have at least a n position code word relevant with p m position information word according to the method for claim 18.

20., wherein in the state in q encoding state, have at least a n position code word relevant with p m position information word according to the method for claim 15.

21. according to the process of claim 1 wherein that the n position code word of the first kind ends up with 0, the n position code word of second class is with 1 ending.

22. according to the process of claim 1 wherein n position code word in first kind of encoding state with 0 beginning, the n position code word in second kind of encoding state is with 0 or 1 beginning.

23. according to the process of claim 1 wherein that this switch process changes with the encoding rate of m/n, m/n is greater than 2/3.

24. according to the method for claim 23, wherein n equals in 13,16 and 19 one.

25. the method according to claim 1 further comprises:

Generate modulation signal by n position code word.

26. the method according to claim 25 further comprises:

On recording medium, write down modulation signal.

27. the method according to claim 25 further comprises:

The signal of transmission modulation.

28. according to the process of claim 1 wherein that this switch process uses conversion table that m position information word is converted to n position code word.

29. according to the method for claim 23, wherein m equals in 9,11 and 13 one.

30. a conversion method comprises:

Receive m position information word, m is an integer here;

M position information word is converted to the n position code word that satisfies the dk constraint, here n is the integer greater than m, d is illustrated in the code word of n position ' 0 ' minimal amount between continuous ' 1 ', and k is illustrated in the code word of n position ' 0 ' maximum number between continuous ' 1 ', n position code word is divided into two groupings of the first kind and two groupings of second class, and be divided into first kind of encoding state and second kind of encoding state, first grouping of the first kind comprises with " 0 " the code word of beginning and ending, the first kind second the grouping comprise with " 1 " and the beginning and with " 0 " ending code word, first grouping of second class comprises the code word that ends up with " 1 " with " 0 " beginning, and second grouping of second class comprises the code word with " 1 " beginning and ending; N position code word in first kind of encoding state is with 0 beginning, and the n position code word in second kind of encoding state is with 0 or 1 beginning;

If wherein previous m position information word is converted to the n position code word of the first kind, the m position information word of then following is converted into the n position code word of first kind of encoding state or second kind of encoding state, if and previous m position information word is converted to the n position code word of second class, the m position information word of then following is converted to the n position code word of first kind of encoding state, and, n position code word is divided into first kind p encoding state and second kind q encoding state, here, p and q are greater than or equal to 1 integer, and the n position code word that each had in p and q the encoding state is different from the n position code word in other p and q the encoding state.

31. an encoding device comprises:

Transducer, receive m position information word, wherein m is an integer, and m position information word is converted to n position code word, here n is the integer greater than m, n position code word is divided into two groupings of the first kind and two groupings of second class, and be divided into first kind of encoding state and second kind of encoding state, first grouping of the first kind comprises the code word that begins and end up with first logical value, second grouping of the first kind comprises with second logical value and beginning and with the code word of first logical value ending, first grouping of second class comprises with first logical value and beginning and with the code word of second logical value ending, second grouping of second class comprises the code word that begins and end up with second logical value; If previous m position information word is converted to the n position code word of the first kind, the m position information word of then following is converted to the n position code word of first kind of encoding state or second kind of encoding state, if and previous m position information word is converted to the n position code word of second class, the m position information word of then following is converted to the n position code word of first kind of encoding state.

32. according to the encoding device of claim 31, wherein transducer received code state and each m position information word, and m position information word is converted to n position code word according to encoding state.

33. the encoding device according to claim 32 further comprises:

The buffer of encoding state is provided to transducer; Wherein

As the part of conversion process, transducer is determined the encoding state of next m position information word, and stores determined encoding state in buffer.

34. according to the encoding device of claim 33, wherein transducer utilizes conversion table that m position information word is converted to n position code word and determines encoding state.

35. the encoding device according to claim 31 further comprises:

Generate the modulator of modulation signal by n position code word.

36. the encoding device according to claim 35 further comprises:

The recording equipment of record modulation signal on recording medium.

37. the encoding device according to claim 35 further comprises:

The transmitter of transmission modulation signal.

38. a method of making recording medium comprises:

M position information word is converted into n position code word, here n is the integer greater than m, n position code word is divided into two groupings of the first kind and two groupings of second class, and be divided into first kind of encoding state and second kind of encoding state, first grouping of the first kind comprises the code word that begins and end up with first logical value, second grouping of the first kind comprises with second logical value and beginning and with the code word of first logical value ending, first grouping of second class comprises with first logical value and beginning and with the code word of second logical value ending, second grouping of second class comprises the code word that begins and end up with second logical value; N position code word in first kind of encoding state begins with first logical value, and the n position code word in second kind of encoding state begins with first or second logical value; If previous m position information word is converted to the n position code word of the first kind, the m position information word of then following is converted to the n position code word of first kind of encoding state or second kind of encoding state, if previous m position information word is converted to the n position code word of second class, the m position information word of then following is converted to the n position code word of first kind of encoding state;

Generate modulation signal by n position code word; And

The described modulation signal of record on recording medium.

39. a coding/decoding method comprises:

Receive n position code word, n is an integer here;

N position code word is converted to m position information word, here m is the integer less than n, n position code word is divided into two groupings of the first kind and two groupings of second class, and be divided into first kind of encoding state and second kind of encoding state, first grouping of the first kind comprises the code word that begins and end up with first logical value, second grouping of the first kind comprises with second logical value and beginning and with the code word of first logical value ending, first grouping of second class comprises with first logical value and beginning and with the code word of second logical value ending, second grouping of second class comprises the code word that begins and end up with second logical value; N position code word in first kind of encoding state begins with first logical value, and the n position code word in second kind of encoding state begins with first or second logical value;

If the n position code word of wherein previous m position information word is the n position code word of the first kind, the m position information word of then following is represented with the n position code word of first kind of encoding state or second kind of encoding state, if and the n position code word of previous m position information word is the n position code word of second class, the m position information word of then following is represented with the n position code word of first kind of encoding state.

40. method according to claim 39, wherein n position code word is divided into first kind p encoding state and second kind q encoding state, here, p and q are greater than or equal to 1 integer, and the n position code word that each had in p and the q encoding state is different from the n position code word in other p and q the encoding state.

41. according to the method for claim 40, wherein switch process determines which in p and q the encoding state be next n position code word belong to, and according to the encoding state of determining current n position code word is converted into m position information word.

42. method according to claim 41, wherein at least one in p and q the encoding state comprises the identical n position code word more than, identical n position codeword mappings is to the m position information word more than, and each identical n position code word has relative different conditions direction, the next one in each state direction indication p and q the encoding state obtains next n position code word thus when m position information word is converted to n position code word.

43. according to the method for claim 42, wherein n position code word satisfies dk constraint, d is illustrated in the code word of n position ' 0 ' minimal amount between continuous ' 1 ' here, and k is illustrated in the code word of n position ' 0 ' maximum number between continuous ' 1 '.

44. according to the method for claim 43, wherein m/n is greater than 2/3, and d=1.

45. according to the method for claim 44, wherein p+q equals 5.

46. according to the method for claim 44, wherein p+q equals 13.

47. according to the method for claim 43, wherein the n position code word of the first kind is with 0 ending, the n position code word of second class is with 1 ending, and the n position code word in first kind of encoding state is with 0 beginning, and the n position code word in second kind of encoding state is with 0 or 1 beginning.

48. the method according to claim 39 further comprises:

Receive modulation signal; And

Be demodulated into n position code word to major general's modulation signal.

49. the method according to claim 39 further comprises:

The modulation signal of from recording medium, regenerating; And

Be demodulated into n position code word to major general's modulation signal.

50. a decoding device comprises:

Transducer, receive n position code word, here n is an integer, and n position code word is converted into m position information word, here m is the integer less than n, n position code word is divided into two groupings of the first kind and two groupings of second class, and be divided into first kind of encoding state and second kind of encoding state, first grouping of the first kind comprises the code word that begins and end up with first logical value, second grouping of the first kind comprises with second logical value and beginning and with the code word of first logical value ending, first grouping of second class comprises with first logical value and beginning and with the code word of second logical value ending, second grouping of second class comprises the code word that begins and end up with second logical value; N position code word in first kind of encoding state begins with first logical value, and the n position code word in second kind of encoding state begins with first or second logical value; If the n position code word of previous m position information word is the n position code word of the first kind, the m position information word of then following is represented with the n position code word of first kind of encoding state or second kind of encoding state, if and the n position code word of previous m position information word is the n position code word of second class, the m position information word of then following is represented with the n position code word of first kind of encoding state.

51. decoding device according to claim 50, wherein n position code word is divided into first kind p encoding state and second kind q encoding state, here, p and q are greater than or equal to 1 integer, and the n position code word that each had in p and the q encoding state is different from the n position code word in other p and q the encoding state.

52. according to the decoding device of claim 51, wherein transducer determines which in p and q the encoding state be next n position code word belong to, and according to the encoding state of determining current n position code word is converted into m position information word.

53. decoding device according to claim 52, wherein at least one in p and q the encoding state comprises the identical n position code word more than, identical n position codeword mappings is to the m position information word more than, and each identical n position code word has relative different conditions direction, next state in each state direction indication p and q the encoding state obtains next n position code word thus when m position information word is converted to n position code word.

54. according to the decoding device of claim 53, wherein n position code word satisfies dk constraint, d is illustrated in the code word of n position ' 0 ' minimal amount between continuous ' 1 ' here, and k is illustrated in the code word of n position ' 0 ' maximum number between continuous ' 1 '.

55. according to the decoding device of claim 54, wherein m/n is greater than 2/3, and d=1.

56. according to the decoding device of claim 55, wherein p+q equals 5.

57. according to the decoding device of claim 55, wherein p+q equals 13.

58. according to the decoding device of claim 54, wherein the n position code word of the first kind is with 0 ending, the n position code word of second class is with 1 ending, and the n position code word in first kind of encoding state is with 0 beginning, and the n position code word in second kind of encoding state is with 0 or 1 beginning.

59. the decoding device according to claim 50 further comprises:

Demodulator is used to receive modulation signal, and is demodulated into n position code word to major general's modulation signal.

60. the decoding device according to claim 50 further comprises:

Reclaim equiment is used for from the recording medium modulation signal of regenerating, and is demodulated into n position code word to major general's modulation signal.

61. a decoding device comprises:

First decoder is used to receive next n position code word, and n is an integer here, and determines the encoding state of next n position code word;

Second decoder is used to receive current n position code word and definite encoding state, and according to the encoding state of determining, current n position code word is converted to m position information word, and wherein m is the integer less than n.

62. decoding device according to claim 61, wherein each n position code word belongs to an encoding state, at least one encoding state comprises the identical n position code word more than, identical n position codeword mappings is to the m position information word more than, and each identical n position code word has relative different conditions direction, next state in each state direction indication encoding state obtains next n position code word thus when m position information word is converted to n position code word.

63. the decoding device according to claim 61 further comprises:

Demodulator is used to receive modulation signal, and is demodulated into n position code word to major general's modulation signal.

64. the decoding device according to claim 61 further comprises:

Reclaim equiment is used for from the recording medium modulation signal of regenerating, and is demodulated into n position code word to major general's modulation signal.

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