Apparatus and methods for use in transmitting and receiving a digital signal, and a record carrier obtained by a transmission apparatus or method

A transmitter apparatus for transmitting a digital data signal via a transmission medium, the transmitter apparatus comprising:

• input means for receiving a digital data signal;
• error protection encoding means for carrying out error protection encoding on the digital data signal so as to obtain an error protection encoded digital data signal, the error protection encoding means being adapted to carry out error protection encoding on packets of p m-bit digital words in the digital data signal so as to obtain error protection encoded packets of n m-bit digital words making up the error protection encoded digital data signal, where n, m and p are integers larger than 1, and n>p;
• channel encoding means for converting the error protection encoded digital data signal into a channel encoded digital data signal, the channel encoding means being adapted to convert the error protection encoded packets of n digital words into converted packets of digital words to form the channel encoded digital data signal, and including:
• generator means for supplying a fixed auxiliary packet having the length of n digital words, and
• calculation means for calculating in a Galois field GF(2.sup.m) a converted digital word in accordance with the formula DW.sub.i +.alpha..FW.sub.i, where DW.sub.i is the binary value corresponding to the i-th digital word in the packet to be converted, FW.sub.i is the fixed binary value corresponding to the i-th digital word in the fixed auxiliary packet, .alpha. is the binary value of a multiplier word having more than one bit, and the converted digital word is the i-th converted digital word in the converted packet of digital words, where i is an integer value running from 1 to n,
• wherein the calculation means is adapted to determine a value .alpha..sub.def for each packet of digital words converted into a converted packet of digital words, and the channel encoding means is further adapted to combine .alpha..sub.def with the converted digital words obtained by the Galois field GF(2.sup.m) calculation of DW.sub.i +.alpha..sub.def.FW.sub.i so as to obtain the converted packet of digital words, the value .alpha..sub.def being determined such that the maximum run length in the serial datastream of the converted packets of digital words is smaller than a first value;
• and
• transmission means for applying the channel encoded digital data signal to the transmission medium.

A transmitter apparatus for transmitting a digital data signal via a transmission medium, the transmitter apparatus comprising:

• input means for receiving a digital data signal;
• error protection encoding means for carrying out error protection encoding on the digital data signal so as to obtain an error protection encoded digital data signal, the error protection encoding means being adapted to carry out error protection encoding on packets of p m-bit digital words in the digital data signal so as to obtain error protection encoded packets of n m-bit digital words making up the error protection encoded digital data signal, where n, m and p are integers larger than 1, and n>p;
• channel encoding means for converting the error protection encoded digital data signal into a channel encoded digital data signal, the channel encoding means being adapted to convert the error protection encoded packets of n digital words into converted packets of digital words to form the channel encoded digital data signal, and including:
• generator means for supplying a fixed auxiliary packet having the length of n digital words,
• calculation means for calculating in a Galois field GF(2.sup.m) a converted digital word in accordance with the formula DW.sub.i +.alpha..FW.sub.i, where DW.sub.i is the binary value corresponding to the i-th digital word in the packet to be converted, FW.sub.i is the fixed binary value corresponding to the i-th digital word in the fixed auxiliary packet, .alpha. is the binary value of a multiplier word having more than one bit, and the converted digital word is the i-th converted digital word in the converted packet of digital words, where i is an integer value running from 1 to n, the calculation means being adapted to determine a value .alpha..sub.def for each packet of digital words converted into a converted packet of digital words, and
• sync word generator means for generating a sync word for each of the converted packets of digital words,
• wherein the channel encoding means is further adapted to combine the sync word, .alpha..sub.def and the converted digital words obtained by the Galois field GF(2.sup.m) calculation of
• DW.sub.i +.alpha..sub.def.FW.sub.i so as to obtain the converted packet of digital words, and the value .alpha..sub.def is determined such that, except for the sync word in the converted packet of digital words, the converted packet does not have a bit pattern that corresponds to the bit pattern of the sync word;
• and
• transmission means for applying the channel encoded digital data signal to the transmission medium.

A transmitter apparatus for transmitting a digital data signal via a transmission medium, the transmitter apparatus comprising:

• input means for receiving a digital data signal;
• error protection encoding means for carrying out error protection encoding on the digital data signal so as to obtain an error protection encoded digital data signal, the error protection encoding means being adapted to carry out error protection encoding on packets of p m-bit digital words in the digital data signal so as to obtain error protection encoded packets of n m-bit digital words making up the error protection encoded digital data signal, where n, m and p are integers larger than 1, and n>p;
• channel encoding means for converting the error protection encoded digital data signal into a channel encoded digital data signal, the channel encoding means being adapted to convert the error protection encoded packets of n digital words into converted packets of digital words to form the channel encoded digital data signal, and including:
• generator means for supplying a first and a second fixed auxiliary packet having the length of n digital words,
• calculation means for calculating in a Galois field GF(2.sup.m) a converted digital word in accordance with the formula DW.sub.i +.alpha..FW.sub.i +.beta..GW.sub.i, where DW.sub.i is the binary value corresponding to the i-th digital word in the packet to be converted, FW.sub.i is the fixed binary value corresponding to the i-th digital word in the first fixed auxiliary packet, GW.sub.i is the fixed binary value corresponding to the i-th digital word in the second fixed auxiliary packet, .alpha. is the binary value of a first multiplier word having more than one bit, .beta. is the binary value of a second multiplier word having more than one bit, and the converted digital word is the i-th converted digital word in the converted packet of digital words, where i is an integer value running from 1 to n, and
• digital sum value determining means for determining a digital sum value of at least a converted packet in the serial datastream of converted packets of digital words that form the channel encoded digital data signal,
• wherein the calculation means is adapted to determine values .alpha..sub.def and .beta..sub.def for each packet of digital words converted into a converted packet of digital words, and the channel encoding means is further adapted to combine .alpha..sub.def and .beta..sub.def with the converted digital words obtained by the Galois field GF(2.sup.m) calculation of DW.sub.i +.alpha..sub.def.FW.sub.i +.beta..sub.def.GW.sub.i so as to obtain said converted packet of digital words, the values .alpha..sub.def for .alpha. and .beta..sub.def for .beta. being such that a running digital sum value of the serial datastream of the converted packets shows a desired pattern as a function of time;
• and
• transmission means for applying the channel encoded digital data signal to the transmission medium.

A receiver apparatus for receiving a digital data signal that has been transmitted as a serial datastream of converted packets via a transmission medium, the receiver apparatus comprising:

• receiving means for receiving a transmission signal from the transmission medium so as to obtain the serial datastream of converted packets at an output thereof;
• channel decoding means for converting a channel encoded signal into a channel decoded signal;
• and
• error correction decoding means for carrying out error detection and correction on a signal applied to an input thereof, the input of the error correction decoding means being coupled to the output of the receiving means, an output of the error correction decoding means being coupled to an input of the channel decoding means, and the digital data signal being available at an output of the channel decoding means;
• wherein the channel decoding means is adapted to reconvert converted packets of digital words, each converted packet including an .alpha. value and n m-bit converted digital words, where n and m are integers larger than 1, and the channel decoding means includes:
• retrieval means for retrieving the .alpha. value, one .alpha. value for each of the converted packets, from the information applied to the input of the channel decoding means,
• generator means for supplying a fixed auxiliary packet also having the length of n digital words, and
• calculation means for calculating in a Galois field GF(2.sup.m) reconverted words in accordance with the formula CW.sub.i -.alpha..FW.sub.i, where CW.sub.i is the binary value corresponding to the i-th digital word in the converted packet, and FW.sub.i is the a fixed binary value corresponding to the i-th digital word in the fixed auxiliary packet, where i is an integer value running from 1 to n.

A receiving apparatus for receiving a digital data signal that has been transmitted as a serial datastream of converted packets via a transmission medium, the receiver apparatus comprising:

• receiving means for receiving a transmission signal from the transmission medium so as to obtain the serial datastream of converted packets at an output thereof;
• channel decoding means for converting a channel encoded signal into a channel decoded signal;
• and
• error correction decoding means for carrying out error detection and correction on a signal applied to an input thereof, the input of the error correction decoding means being coupled to the output of the receiving means, an output of the error correction decoding means being coupled to an input of the channel decoding means, and the digital data signal being available at an output of the channel decoding means;
• wherein the channel decoding means is adapted to reconvert converted packets of digital words, each converted packet including an .alpha. value, a .beta. value and n m-bit converted digital words, where n and m are integers larger than 1, and the channel decoding means includes:
• retrieval means for retrieving the .alpha. and .beta. values, one .alpha. and one value for each of the converted packets, from the information applied to the input of the channel decoding means,
• generator means for supplying a first and a second fixed auxiliary packet also having the length of n digital words, and
• calculation means for calculating in a Galois field GF(2.sup.m) reconverted words in accordance with the formula CW.sub.i -.alpha..FW.sub.i -.beta..GW.sub.i, where CW.sub.i is the binary value corresponding to the i-th digital word in the converted packet, FW.sub.i is the fixed binary value corresponding to the i-th digital word in the first fixed auxiliary packet, and GW.sub.i is the fixed binary value corresponding to the i-th digital word in the second fixed auxiliary packet, where i is an integer value running from 1 to n.

A method for processing a digital data signal for transmission via a transmission medium, the method comprising:

• carrying out an error protection encoding on a digital signal so as to obtain an error protection encoded digital signal by carrying out error protection encoding of packets of p m-bit digital words included in the digital signal so as to obtain error protection encoded packets of n m-bit digital words making up the error protection encoded digital signal, where n, m and p are integers larger than 1, and n>p;
• and
• converting the error protection encoded digital signal into a channel encoded digital signal by converting the error protection encoded packets of n digital words into converted packets of digital words to form the channel encoded digital data signal, which conversion includes:
• supplying a fixed auxiliary packet having the length of n digital words, and
• calculating in a Galois field GF(2.sup.m) a converted digital word in accordance with a formula which at least includes DW.sub.i +.alpha..FW.sub.i, where DW.sub.i is the binary value corresponding to the i-th digital word in the packet to be converted, FW.sub.i is the fixed binary value corresponding to the i-th digital word in the fixed auxiliary packet, .alpha. is the binary value of a multiplier word including more than one bit, and the converted digital word is the i-th converted digital word in the converted packet of digital words, where i is an integer value running from 1 to n, such calculation including determining at least a value .alpha..sub.def for each packet of digital words converted into a converted packet of digital words;
• wherein the channel encoding further includes combining .alpha..sub.def with the converted digital words obtained by the Galois field GF(2.sup.m) calculation in accordance with the formula so as to obtain the converted packet of digital words.

A method for obtaining a digital data signal that has been transmitted as a serial datastream of converted packets via a transmission medium, the method comprising:

• carrying out error detection and correction on the serial datastream of converted packets obtained from the transmission medium to obtain a channel encoded signal;
• and
• converting the channel encoded signal into a channel decoded signal by reconverting converted packets of digital words included in the channel encoded signal, each converted packet having an .alpha. value and n m-bit converted digital words, where n and m are integers larger than 1, which conversion includes:
• retrieving the .alpha. value, one .alpha. value for each of the converted packets, from the converted packets,
• supplying a fixed auxiliary packet having the length of n digital words, and
• calculating in a Galois field GF(2.sup.m) reconverted words in accordance with a formula which includes at least the expression CW.sub.1 -.alpha..FW.sub.i, where CW.sub.i is the binary value corresponding to the i-th digital word in the converted packet and FW.sub.i is the fixed binary value corresponding to the i-th digital word in the fixed auxiliary packet, where i is an integer value running from 1 to n.

An apparatus for processing a digital data signal for transmission via a transmission medium, the apparatus comprising:

• error protection encoding means for carrying out an error protection encoding on a digital signal so as to obtain an error protection encoded digital signal by carrying out error protection encoding of packets of p m-bit digital words included in the digital signal so as to obtain error protection encoded packets of n m-bit digital words making up the error protection encoded digital signal, where n, m and p are integers larger than 1, and n>p;
• and
• channel encoding means for converting the error protection encoded digital signal into a channel encoded digital signal by converting the error protection encoded packets of n digital words into converted packets of digital words to form the channel encoded digital data signal, the channel encoding means including:
• generator means for supplying a fixed auxiliary packet having the length of n digital words, and
• calculation means for calculating in a Galois field GF(2.sup.m) a converted digital word in accordance with a formula which at least includes DW.sub.i +.alpha..FW.sub.i, where DW.sub.i is the binary value corresponding to the i-th digital word in the packet to be converted, FW.sub.i is the fixed binary value corresponding to the i-th digital word in the fixed auxiliary packet, .alpha. is the binary value of a multiplier word including more than one bit, and the converted digital word is the i-th converted digital word in the converted packet of digital words, where i is an integer value running from 1 to n;
• wherein the calculation means determines at least a value .alpha..sub.def for each packet of digital words converted into a converted packet of digital words, and the channel encoding means combines .alpha..sub.def with the converted digital words obtained by the Galois field GF(2.sup.m) calculation in accordance with the formula so as to obtain the converted packet of digital words.

An apparatus for obtaining a digital data signal that has been transmitted as a serial datastream of converted packets via a transmission medium, the apparatus comprising:

• error correction decoding means for carrying out error detection and correction the serial datastream of converted packets obtained from the transmission medium to obtain a channel encoded signal;
• and
• channel decoding means for converting the channel encoded signal into a channel decoded signal by reconverting converted packets of digital words included in the channel encoded signal, each converted packet having an .alpha. value and n m-bit converted digital words, where n and m are integers larger than 1, the channel decoding means including:
• retrieval means for retrieving the .alpha. value, one .alpha. for each of the converted packets, from the converted packets,
• generator means for supplying a fixed auxiliary packet having the length of n digital words, and
• calculation means for calculating in a Galois field GF(2.sup.m) reconverted words in accordance with a formula which includes at least the expression CW.sub.i -.alpha..FW.sub.i, where CW.sub.i is the binary value corresponding to the i-th digital word in the converted packet and FW.sub.i is the fixed binary value corresponding to the i-th digital word in the fixed auxiliary packet, where i is an integer value running from 1 to n.