Error correction and detection apparatus and method
First Claim
1. Apparatus for receiving input digital data coded using a predetermined error correction code, said apparatus comprisingfirst means capable of correcting a first number of errors in the received data and capable of detecting errors in the received data at a first probability rate;
- second means capable of correcting a second number of errors in the received data, which is greater than said first number of errors, and capable of detecting errors in the received data at a second probability rate less than said first probability rate;
means for deriving an error signal from said received data; and
control means for applying said received data to said first means, and subsequently in response to said error signal indicating a first predetermined number of corrected errors in said received data, which is less than or equal to said first number, thereafter applying said received data to said second means, and thereafter in response to a subsequent error signal indicating a second predetermined number of corrected errors in said received data, which is less than or equal to said second number and greater than said first number, thereafter again applying said received data to said first means.
4 Assignments
0 Petitions
Accused Products
Abstract
A decoder is arranged to operate as a single-bit error correction circuit (ECC) and as a multiple-bit error detection circuit (EDC). The decoder starts and remains in the ECC state as long as no errors are detected in a received data message. When an error is detected or corrected in a received data message, the decoder switches to the EDC state where it remains as long as errors are detected in the received data message. When no errors are detected in the received data message, the decoder switches back to the ECC state. In a generalized multistate decoder, switching occurs from one state to another state, each state having a different error correcting capability, in response to a predetermined number of errors corrected or detected in the received data.
-
Citations
19 Claims
-
1. Apparatus for receiving input digital data coded using a predetermined error correction code, said apparatus comprising
first means capable of correcting a first number of errors in the received data and capable of detecting errors in the received data at a first probability rate; -
second means capable of correcting a second number of errors in the received data, which is greater than said first number of errors, and capable of detecting errors in the received data at a second probability rate less than said first probability rate; means for deriving an error signal from said received data; and control means for applying said received data to said first means, and subsequently in response to said error signal indicating a first predetermined number of corrected errors in said received data, which is less than or equal to said first number, thereafter applying said received data to said second means, and thereafter in response to a subsequent error signal indicating a second predetermined number of corrected errors in said received data, which is less than or equal to said second number and greater than said first number, thereafter again applying said received data to said first means. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A data communication system including a data transmitter and a data receiver connected over a data path,
said data transmitter comprising means for generating and transmitting digital data coded using an error correcting code to said receiver; - and
said receiver comprising means for receiving said digital data; first means capable of correcting a first number of errors in the received data and capable of detecting errors in the received data at a first probability rate; second means capable of correcting a second number of errors in the received data, which is greater than said first number of errors, and capable of detecting errors in the received data at a second probability rate less than said first probability rate; means for deriving an error signal from said received data; and control means for applying said received data to said first means, and subsequently in response to said error signal indicating a first predetermined number of corrected errors in said received data, which is less than or equal to said first number, thereafter applying said received data to said second means, and thereafter in response to a subsequent error signal indicating a second predetermined number of corrected errors in said received data, which is less than or equal to said second number and greater than said first number, thereafter again applying said received data to said first means.
- and
-
7. A method of operating a data receiver for receiving input digital data coded using a predetermined error correction code, said method comprising the steps of:
-
(a) deriving an error signal from said received data, (b) applying said received data to a first correcting step c, (c) correcting a first number of errors in the receiving data and detecting errors in the received data at a first probability rate; (d) in response to said error signal indicating a first predetermined number of corrected errors in said received data, which is less than or equal to said first number, applying subsequent-received data to a second correcting step e, (e) correcting a second number of errors in said subsequent-received data, which is greater than said first number of errors, and detecting errors in said subsequent-received data at a second probability rate less than said first probability rate; and (f) in response to said error signal indicating that a second predetermined number of corrected errors in said subsequent-received data, which is less than or equal to said second number and greater than said first number, applying newly received data to said first correcting step (c).
-
-
8. Apparatus for receiving input digital data coded using an error correction code, said apparatus comprising
error correcting circuit (ECC) means for detecting one or more errors and for correcting a single-bit error in the received data using said error correction code, error detecting circuit (EDC) means for detecting one or more errors in the received data using said error correction code, means for deriving an error signal in a predetermined manner from said received data, and switch means responsive to the absence of an error signal received from said deriving means for switching the detecting of said received data from said EDC means to said ECC means and responsive to the presence of said error signal for switching the detecting of said received data from said ECC means to said EDC means.
-
17. A data communication system including a data transmitter and a data receiver connected over a data path,
said data transmitter comprising means for generating a data message including an error correction code and means for transmitting said data message to said receiver, and said receiver comprising means for receiving said data message, an error correcting circuit (ECC) means for detecting one or more errors and correcting a single-bit error in the received data message using said error correction code, an error detecting circuit (EDC) means for detecting one or more errors in the received data message using said error correction code and means for deriving an error signal in a predetermined manner from said received data, and switch means responsive to the absence of an error signal received from said deriving means for switching the detecting of said received data from said EDC means to said ECC means and responsive to the presence of said error signal for switching the detecting of said received data message from said ECC means to said EDC means.
-
18. A method of operating a data receiver for receiving input digital data coded using an error correction code therein, said method comprising the steps of:
-
(a) detecting one or more errors and correcting a single-bit error in the received data using an error correcting circuit (ECC) and said error correction code, (b) in response to an error correction or detection signal derived in said detecting step (a), switching said received data from said detecting step (a) to detecting step (c), (c) detecting one or more errors in received data using an error detecting circuit (EDC) and said error correction code, and (d) in response to an absence of an error signal in said detecting step (c), switching said received data to said detecting step (a).
-
-
19. A method of operating a data communication system including a data transmitter and a data receiver connected over a data path, said method comprising the steps of:
-
at said data transmitter generating and transmitting a data message including an error correction code and at said receiver (a) detecting one or more errors and correcting a single-bit error in the received data message using an error correcting circuit (ECC) and said error correction code, (b) in response to an error correction or detection signal derived in said detecting step (a), switching said received data message from said detecting step (a) to detecting step (c), (c) detecting one or more errors in received data using an error detecting circuit (EDC) and said error correction code, and (d) in response to an absence of an error signal in said detecting step (c), switching said received data to said detecting step (a).
-
Specification