摘要:
This invention relates to an error correction upon reproduction of digital signals. The error correction is performed by decoding code words such as cross-interleaved Reed Solomon codes, in which first code blocks are formed by a plurality of information words which are in the first arrangement state and a plurality of first check words which are produced by codes associated with the plurality of information words with a Hamming distance of d.sub.1, and second code blocks are formed by a plurality of information words and a plurality of first check words which are in the second arrangement state and which consist of the said plurality of information words and the said plurality of first check words which are respectively included in the different first code blocks, and by a plurality of second check words which are produced by codes associated with the plurality of information words and the plurality of first check words with a Hamming distance of d.sub.2. At the first decoding stage, errors are detected and at the same time the flags indicative of the decoding states are added with respect to the second code blocks. At the second decoding stage, in accordance with the contents of the flags and on the basis of a combination of p.sub.2 and q selected from their combinations satisfying 2p.sub.2 +q.ltoreq.d.sub.1 -1, errors are detected and errors of p.sub.2 words are corrected and erasures of q words to which the flags were added are corrected with respect to the first code blocks.
摘要:
A method of transmitting a digital signal in the form of successive signal frames containing codes for detecting and correcting errors of the digital signal for reducing degradation in the quality of the reproduced sound due to generation of the code errors in a digitized audio signal transmission system. An analog signal such as an audio signal is sampled and subjected to A/D conversion. The sample word thus obtained is divided into a plurality of symbol elements. Parity words for detecting and correcting code errors are added to every group of a predetermined number of the information symbols through an interleave procedure before being transmitted. The method includes the steps of applying a first frame of symbols, taken one from each input channel, and having a first arrangement state, to a first error-correcting code encoder to generate a series of first parity words; delaying each of the symbols in the first frame and each of the first parity words by a respective different delay time in a unit of the sample word at a delay line to provide a resulting second frame of symbols in a second arrangement state; applying the second frame of symbols to a second error-correcting code encoder to generate a series of second parity words; and transmitting said second frame of symbols together with said second parity words.
摘要:
The present invention relates to an information providing system. More particularly, this invention relates to an information management apparatus capable of reliable management of distributed information and an information providing system employing the same information management apparatus. The information management apparatus comprises a main information reproducing means for reproducing main information recorded in a given recording medium; and a reproduction management means for managing the main information reproducing means for reproducing the main information. The present invention provides a receiving means provided with a means for recording distributed information and control information limiting the number of main information reproducing cycles on a recording medium, and a main information reproducing means provided with a reproduction disabling means for limiting the reproduction of main information.
摘要:
The present invention relates to an information providing system. More particularly, this invention relates to an information management apparatus capable of reliable management of distributed information and an information providing system employing the same information management apparatus. The information management apparatus comprises a main information reproducing means for reproducing main information recorded in a given recording medium; and a reproduction management means for managing the main information reproducing means for reproducing the main information. The present invention provides a receiving means provided with a means for recording distributed information and control information limiting the number of main information reproducing cycles on a recording medium, and a main information reproducing means provided with a reproduction disabling means for limiting the reproduction of main information.
摘要:
The present invention relates to an information providing system. More particularly, this invention relates to an information management apparatus capable of reliable management of distributed information and an information providing system employing the same information management apparatus. The information management apparatus comprises a main information reproducing means for reproducing main information recorded in a given recording medium; and a reproduction management means for managing the main information reproducing means for reproducing the main information. The present invention provides a receiving means provided with a means for recording distributed information and control information limiting the number of main information reproducing cycles on a recording medium, and a main information reproducing means provided with a reproduction disabling means for limiting the reproduction of main information.
摘要:
The present invention relates to an information providing system. More particularly, this invention relates to an information management apparatus capable of reliable management of distributed information and an information providing system employing the same information management apparatus. The information management apparatus comprises a main information reproducing means for reproducing main information recorded in a given recording medium; and a reproduction management means for managing the main information reproducing means for reproducing the main information. The present invention provides a receiving means provided with a means for recording distributed information and control information limiting the number of main information reproducing cycles on a recording medium, and a main information reproducing means provided with a reproduction disabling means for limiting the reproduction of main information.
摘要:
An information management apparatus capable of reliable management of distributed information and an information providing system employing the same information management apparatus has a main information reproducing system for reproducing main information recorded in a given recording medium; and a reproduction management system for managing the main information reproducing system for reproducing the main information. A receiver is provided with a unit for recording distributed information and control information limiting the number of main information reproducing cycles on a recording medium, and a main information reproducing system provided with a reproduction disabling function for limiting the reproduction of main information.
摘要:
The present invention relates to an information providing system. More particularly, this invention relates to an information management apparatus capable of reliable management of distributed information and an information providing system employing the same information management apparatus. The information management apparatus comprises a main information reproducing means for reproducing main information recorded in a given recording medium; and a reproduction management means for managing the main information reproducing means for reproducing the main information. The present invention provides a receiving means provided with a means for recording distributed information and control information limiting the number of main information reproducing cycles on a recording medium, and a main information reproducing means provided with a reproduction disabling means for limiting the reproduction of main information.
摘要:
A digital signal recording/reproducing apparatus capable of recording and reproducing digital signals having differences in respect to sampling frequency thereof and the number of quantization bits per sample by means of a common circuit arrangement includes means for varying revolution speed of rotating heads for recording and reproduction or traveling speed of a recording medium as a function of different sampling frequencies. A signal processing circuit for processing the digital signals so as to be suited for the recording on the recording medium is controlled by a clock signal of which frequency is changed in dependence on the different sampling frequencies. The signal processing circuit is arranged so that PCM data contained in a frame is constituted by a number of bits which is equal to a common multiple of the different quantization bit numbers and added with a common frame synchronizing signal and common error detection and correction codes to thereby prepare the PCM signal of the frame arrangement. The digital signals which differ in the sampling frequency and the quantization bit numbers can be recorded by same recording and reproducing apparatus with an improved efficiency with a same wavelength and in a same signal format.
摘要:
In a recording operation by a rotary head type PCM recording/reproducing apparatus including at least two magnetic heads, the odd-numbered sample data and the even-numbered sample data are discriminatively extracted and stored. The stored data corresponding to an amount of data outputted from the A/D converter within a predetermined time is selectively read out and supplied to the two heads to thereby record the data in such a manner that the odd-numbered data and the even-numbered data are recorded separately on a track basis or alternatively recorded separately on a preceding half and a succeeding half of each track. The error detecting and correcting code is prepared on the basis of the data to be recorded in each track. In reproduction of the recorded data, upon detection of a drop-out of the data from one of the two heads, the drop-out data is corrected through interpolation procedure to thereby reconstitute the original analog signal.