JPH01211372A - Digital magnetic picture recording and reproducing device - Google Patents
Digital magnetic picture recording and reproducing deviceInfo
- Publication number
- JPH01211372A JPH01211372A JP3817088A JP3817088A JPH01211372A JP H01211372 A JPH01211372 A JP H01211372A JP 3817088 A JP3817088 A JP 3817088A JP 3817088 A JP3817088 A JP 3817088A JP H01211372 A JPH01211372 A JP H01211372A
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- Prior art keywords
- signals
- multilevel
- magnetic recording
- digital
- value
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- 230000015556 catabolic process Effects 0.000 description 6
- 238000006731 degradation reaction Methods 0.000 description 6
- 230000004044 response Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
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Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、ディジタル磁気録画再生装置に関し、特にテ
レビジョン信号を多値ディジタル符号に変換し、磁気記
録媒体に記録する際に適した変調信号に変換して記録す
る装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a digital magnetic recording and reproducing device, and in particular to a method for converting a television signal into a multilevel digital code and converting it into a modulation signal suitable for recording on a magnetic recording medium. This relates to a device for recording images.
従来の技術
テレビジョン信号をディジタル符号に変換し、磁気記録
媒体に記録する際に用いられる変調信号は、大別して、
ＮＲＺ５ｔｔｌｌとインターリーブＮＲＺＩｉ調と３値
パーシヤルレスポンスである。Conventional technology The modulation signals used to convert television signals into digital codes and record them on magnetic recording media can be roughly divided into:
These are NRZ5ttll, interleaved NRZIi tone, and 3-level partial response.
ＮＲＺ変調は２値ディジタル符号をビット“１″を１つ
の極性レベルに対応させ、ビット“０”を反対極性レベ
ルに対応させる。このため、変調１３号の占有帯域は、
直流成分から０．７５ｆＣまで（ｒｃ ：クロンク周波
数、コサインロールオフに−０，５を考慮）分布する。NRZ modulation is a binary digital code in which bit "1" corresponds to one polarity level and bit "0" corresponds to the opposite polarity level. Therefore, the occupied band of modulation No. 13 is
It is distributed from the DC component to 0.75 fC (rc: Cronk frequency, considering -0.5 for cosine roll-off).
一方、磁気記録媒体の記録再生特性は、低域では微分特
性を示すため、直流成分を含む低域信号は再生されず、
また、高域では磁気記録媒体と磁気ヘッド間のスペース
等によって劣化する。したがってＮＲＺ変調を用いる場
合は、８−ＩＯコード変換等のコード変換を行なった後
、直流成分を含む低域成分をなくし用いる。また、前記
インターリーブＮＲＺＩ変調は、前記、磁気記録媒体の
記録再生特性を利用して、ＮＲＺ変調記録されたディジ
タル符号を、３値レベルとして再生し復調するものであ
る。この場合、記録側に直流成分はあるが、再生側には
、直流成分はなくなる。また、３値パーシヤルレスポン
スは、前記、インターリーブＮＲＺＩ変調を改良して、
記録側も３値レベルとして記録し、再生側も３値レベル
として再生し復調するものである。よって記録再生とも
に直流成分はなくなる（たとえば“ディジタルＶＴＲと
その実用化に向けての問題点”中用省三（昭和５７．２
Ｎ ＨＫ技研月報））。On the other hand, the recording and reproducing characteristics of magnetic recording media exhibit differential characteristics in the low frequency range, so low frequency signals containing DC components are not reproduced.
In addition, at high frequencies, it deteriorates due to the space between the magnetic recording medium and the magnetic head. Therefore, when using NRZ modulation, after code conversion such as 8-IO code conversion is performed, low frequency components including DC components are eliminated and used. Furthermore, the interleaved NRZI modulation uses the recording and reproducing characteristics of the magnetic recording medium to reproduce and demodulate the digital code recorded in the NRZ modulation as a ternary level. In this case, there is a DC component on the recording side, but there is no DC component on the reproduction side. In addition, the ternary partial response is obtained by improving the interleaved NRZI modulation described above.
The recording side also records as a ternary level, and the reproducing side also reproduces and demodulates as a ternary level. Therefore, there is no direct current component in both recording and reproduction (for example, "Digital VTR and Problems in its Practical Application" by Shozo Nakayo (February 1982).
NHK Giken Monthly Report)).
発明が解決しようとする課題 前記ＮＲＺ変調、インターリーブＮＲＺＩ変調。Problems that the invention aims to solve The NRZ modulation and interleaved NRZI modulation.
３値パーシヤルレスポンスは、直流成分を含む低域信号
成分はなくなっているが、完全ではなく、隣接トラック
からのクロストークを防ぐために、トラック間にガード
を付けるか、もしくは、アジマス角をおおきくして、べ
た書きを可能としている。また、２値ディジタル符号を
基本としているため、周波数利用効率（単位帯域当り伝
送できるビットレイト）は、あまり改善できず、周波数
利用効率を改善するためには、記録帯域を広げるか、も
しくは、同時に記録するチャンネル数を増やすしかなか
った。また、磁気記録媒体に記録する変調信号は、占有
帯域に、一応に分布しているため、磁気記録媒体の再生
Ｓ／Ｎの悪い高域部分を強調して使用しなくてはならな
かった。In the three-level partial response, the low-frequency signal components including the DC component are eliminated, but it is not perfect, and in order to prevent crosstalk from adjacent tracks, a guard must be placed between the tracks or the azimuth angle must be increased. This allows for solid writing. In addition, since it is based on binary digital codes, the frequency usage efficiency (the bit rate that can be transmitted per unit band) cannot be improved much.In order to improve the frequency usage efficiency, it is necessary to widen the recording band or to I had no choice but to increase the number of channels to record. Furthermore, since the modulation signal recorded on the magnetic recording medium is distributed in the occupied band, it is necessary to emphasize the high frequency portion of the magnetic recording medium where the reproduction S/N is poor.
課題を解決するための手段
本発明は上記課題を解決するため、テレビジョン信号を
ディジタル符号に変換するＡ／Ｄ変換器と、前記ディジ
タル符号を、多値ディジタル符号に変換する多値変換器
と、前記多値ディジタル符号を多値直行振幅変調（多値
ＱＡＭ）する多値ＱＡＭ器でもって、磁気記録媒体に記
録し、前記記録媒体からの再生信号を、前記多値ディジ
タル符号に復調する多値ＱＡＭ復調器と前記磁気記録媒
体の周波数劣化をたたみ込み符号と見なして、前記多値
ディジタル符号を、前記ディジタル符号に変換するビタ
ビ復号器と前記ディジタル符号を前記テレビジョン信号
に変換するＤ／Ａ変換器でもって、前記磁気記録媒体か
ら、前記テレビジョン信号を再生するよう構成したもの
である。Means for Solving the Problems In order to solve the above problems, the present invention provides an A/D converter that converts a television signal into a digital code, and a multi-value converter that converts the digital code into a multi-value digital code. , a multi-value digital code is recorded on a magnetic recording medium using a multi-value QAM device that performs multi-value quadrature amplitude modulation (multi-value QAM), and a reproduced signal from the recording medium is demodulated into the multi-value digital code. a value QAM demodulator, a Viterbi decoder that converts the multilevel digital code into the digital code by regarding the frequency degradation of the magnetic recording medium as a convolutional code, and a D/D converter that converts the digital code into the television signal. The television signal is reproduced from the magnetic recording medium using an A converter.
作用
本発明は上記した構成により、テレビジョン信号を多値
ディジタル符号に変換し、ＣＡＭ変調して記録している
ため、搬送波近傍にスペクトルが集中し、前記ガートバ
ンドなしで、また、アジマス角をそれほど大きくせずに
、べた書きできる。Effect of the Invention The present invention converts a television signal into a multilevel digital code, modulates it with CAM, and records it with the above-described configuration, so that the spectrum is concentrated near the carrier wave, and the azimuth angle can be changed without using the guard band. You can write all over the page without making it too large.
また、ＣＡＭ変調は搬送波Ｃ／Ｎで伝送Ｓ／Ｎが′きま
り、伝送Ｓ／Ｈの悪い高域部分をそれほど使用しなくて
もすむ、さらに、磁気記録媒体の周波数劣化をたたみ込
み符号とみなして復号するため、伝送Ｓ／Ｎの悪い高域
部分を強調せず復号できる。In addition, in CAM modulation, the transmission S/N is determined by the carrier wave C/N, so there is no need to use the high frequency part where the transmission S/H is poor.Furthermore, the frequency deterioration of the magnetic recording medium is treated as a convolution code. Since the high frequency portion with poor transmission S/N can be decoded without emphasizing it.
また、多値ディジタル符号を使用しているため、磁気記
録媒体の伝送Ｓ／Ｎが許容できる限り周波数利用効率を
改善することができる。また、磁気記録媒体に記録する
際にバイアス信号を加算して記録するので、磁気記録媒
体の再生歪の影響を受けずに記録再生することができる
。Furthermore, since a multilevel digital code is used, frequency utilization efficiency can be improved as long as the transmission S/N of the magnetic recording medium is allowable. Furthermore, since a bias signal is added and recorded when recording on a magnetic recording medium, recording and reproduction can be performed without being affected by reproduction distortion of the magnetic recording medium.
実施例
以下、本発明の一実施例について図面を参照して説明す
る。第１図ｔａ１． （ｂ）は本発明の要部構成を示す
要部ブロック図である。入力されたテレビジョン信号は
、Ａ／Ｄ変換器１でｎビットディジタル符号に変換し、
多値変換器２に出力される。つぎに、前記多値変換器２
は、前記ｎビットディジタル符号を、２ ｎｌｔ値ディ
ジタルＩ信号および２ガフ２値ディジタルＱ信号に変換
し、多値ＱＡＭ器３に出力する。つぎに、前記多値ＱＡ
Ｍ器３では、多値直交振幅変調して加算器４に出力する
。EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings. Figure 1 ta1. (b) is a main part block diagram showing the main part configuration of the present invention. The input television signal is converted into an n-bit digital code by an A/D converter 1,
It is output to the multi-value converter 2. Next, the multi-value converter 2
converts the n-bit digital code into a 2nlt-value digital I signal and a 2-gaff binary digital Q signal, and outputs them to the multilevel QAM unit 3. Next, the multivalued QA
The M unit 3 performs multilevel orthogonal amplitude modulation and outputs it to the adder 4.
たとえば、ｎ＝４の場合、４ビットディジタル符号は、
第２図（８１に示す波形となり、４値ディジタルＩ信号
およびＱ信号は、第２図中）に示す波形となる０次に、
前記４値ディジタル■信号およびＱ信号は、多値直交振
幅変調されると第２図（Ｃ１に示す信号配置図となる０
次に、第１図にもどり、加算器４では、磁気記録媒体の
再生歪を除去するため、バイアス信号発生器５からの出
力であるバイアス信号と前記多値ＱＡＭ器３の出力であ
る多値直交振幅変調信号とを加算する（第３図に示す周
波数アロケイジョン図となり、バイアス信号は、多値振
幅変調信号の最高周波数ｊ ｗａｘの３倍以上に設定す
る）０次に、加算器４の出力は、ＲＥＣアンプ６、磁気
へラド７を介して、磁気記録媒体８にバイアス記録され
る０次に、再生側では、磁気記録媒体８の再生信号を、
磁気ヘッド７、ヘッドアンプ９を介して再生する。次に
、多値ＣＡＭ復調器ｌＯでは、前記ヘンドアツブ９の出
力である多値直交振幅変調信号を多値ディジタルＩおよ
びＱ信号に復調し、とタビ復号器１１に出力する。For example, if n=4, the 4-bit digital code is
The 0th order has the waveform shown in Fig. 2 (81, and the 4-value digital I signal and Q signal have the waveform shown in Fig. 2).
When the four-value digital ■ signal and the Q signal are subjected to multi-value orthogonal amplitude modulation, they become the signal arrangement diagram shown in FIG. 2 (C1).
Next, returning to FIG. 1, in order to remove reproduction distortion of the magnetic recording medium, the adder 4 uses the bias signal output from the bias signal generator 5 and the multi-value signal output from the multi-value QAM unit 3. (The frequency allocation diagram shown in FIG. 3 is obtained, and the bias signal is set to three times or more the highest frequency j wax of the multilevel amplitude modulation signal.) Next, the output of the adder 4 is added. is bias-recorded on the magnetic recording medium 8 via the REC amplifier 6 and the magnetic head 7. On the reproduction side, the reproduction signal of the magnetic recording medium 8 is
It is reproduced via a magnetic head 7 and a head amplifier 9. Next, the multi-level CAM demodulator IO demodulates the multi-level quadrature amplitude modulation signal, which is the output of the hand adder 9, into multi-level digital I and Q signals, and outputs them to the Tavi decoder 11.
次に、前記ビタビ復号器１１は、同一構成のＩ信号用ビ
タビ復号器１３とＱ信号用ビタビ復号器１４とから構成
される。■およびＱ信号用ビタビ復号器１３，１４では
、磁気記録再生により生じた周波数劣化をたたみ込み符
号とみなして復号を行う、すなわち、磁気記録再生を行
うと第４図＋ａｌに示すごとく、周波数劣化が生じ、多
値ディジクル■およびＱ信号は、第４図ｔｂ＋に示すご
とく周波数劣化が生じる。すなわち、多値ディジタル■
信号およびＱ信号のいずれかが、第４図（Ｃ１に示すイ
ンパルス波形の場合、第５図＋ｄ）のような波形となる
。よって、多値ディジタルＩ信号およびＱ信号は、第４
図（ｄｌに示す（−−Ｃ−１ｌ・・・ｃ−１ｃ、ｃｌ・
・・Ｃ１１−−）のたたみ込みとなり、たたみ込み符号
とみなせる。よって、第１図のＩおよびＱ信号用ビタビ
復号器１３．１４を、第５図のごとく構成する。すなわ
ち、周波数劣化情報回路２２では、まえもって、前記第
４図ｆｄ）に示す係数（−−Ｃ−Ａ・・・Ｃ−Ｉ Ｃ
Ｉ ＣＩ・・・Ｃ，−−）を記録しておく。Next, the Viterbi decoder 11 is composed of an I signal Viterbi decoder 13 and a Q signal Viterbi decoder 14, which have the same configuration. In the Viterbi decoders 13 and 14 for the Q and Q signals, decoding is performed by regarding the frequency deterioration caused by magnetic recording and reproduction as a convolution code.In other words, when magnetic recording and reproduction is performed, the frequency deterioration occurs as shown in Figure 4+al. occurs, and the frequency of the multi-level digital signal (2) and the Q signal is degraded as shown in tb+ in FIG. In other words, multivalued digital ■
Either the signal or the Q signal has a waveform as shown in FIG. 4 (in the case of the impulse waveform shown in C1, FIG. 5+d). Therefore, the multilevel digital I signal and Q signal are
Figure (shown in dl (--C-1l...c-1c, cl.
...C11--), and can be regarded as a convolutional code. Therefore, the Viterbi decoders 13 and 14 for I and Q signals shown in FIG. 1 are configured as shown in FIG. 5. That is, in the frequency deterioration information circuit 22, the coefficients (--C-A...C-I C
Record I CI...C, --).
つぎに、パスメトリック計算回路２１は、ｎ値発生回路
３１．遅延素子３２．３３．３４，３５゜乗算回路３６
，３７．３８．３９．および加算回路４０とから構成さ
れ、ｎ値信号レベルに対応するたたみ込み符号値を計算
し、ＡＣ３回路２３に出力する。ＡＣＳ回路２３では、
端子２０より人力された、復調多値ディジタルＩ信号（
もしくはＱ信号）と符号間距離を比較し、最も復調多値
ディジタル■信号（もしくはＱ信号）に近いｎ値信号が
選択される０次に、バスメモリ回路２４では、パスメト
リック計算回路２１から出力された復調多値ディジタル
■信号（もしくはＱ信号）に符号間距離が最も近い符号
列に従って、ｎ ／ ２ビットディジタル符号を出力し
、！信号およびＱ信号用ビタビ復号器１３．１４合せて
ｎピントディジタル符号を出力する。最後に、第１図に
もどって、Ｄ／Ａ変換器１２では、前記ビタビ復号器１
１の出力であるｎビットディジタル符号に従って、前記
テレビジョン信号が出力される。Next, the path metric calculation circuit 21 generates an n value generation circuit 31 . Delay element 32, 33, 34, 35° multiplication circuit 36
, 37.38.39. and an adder circuit 40, which calculates the convolution code value corresponding to the n-value signal level and outputs it to the AC3 circuit 23. In the ACS circuit 23,
A demodulated multilevel digital I signal (
or Q signal) and the intersymbol distance, and the n-value signal closest to the demodulated multilevel digital signal (or Q signal) is selected. Next, the bus memory circuit 24 outputs the signal from the path metric calculation circuit 21. An n/2-bit digital code is output according to the code string with the closest inter-symbol distance to the demodulated multilevel digital ■ signal (or Q signal), and! The Viterbi decoders 13 and 14 for signal and Q signal together output n-pin digital codes. Finally, returning to FIG. 1, in the D/A converter 12, the Viterbi decoder 1
The television signal is output according to an n-bit digital code that is an output of 1.
上記実施例においては、周波数劣化情報回路２２にまえ
もって周波数劣化情報が、記憶された構成について述べ
たが、周波数劣化を検出するバイロフト信号を磁気記録
媒体に記録することによって、周波数劣化を積出して復
号することもできる。In the above embodiment, the configuration is described in which frequency degradation information is stored in advance in the frequency degradation information circuit 22, but by recording a biloft signal for detecting frequency degradation on a magnetic recording medium, frequency degradation is accumulated and decoded. You can also.
また、上記実施例においては、ｎピントディジタル符号
を、２″値ディジタル符号に変換する多値変換器を用い
た場合についてのべたが、多値レベル数を増やして、誤
り訂正符号を付加する符号化変調方式を用いることによ
り、さらに伝送に必要なＳ／Ｎを減らすことができる。In addition, in the above embodiment, a case has been described in which a multi-value converter is used to convert an n-pin digital code into a 2''-value digital code, but a code in which the number of multi-value levels is increased and an error correction code is added. By using the modulation method, the S/N required for transmission can be further reduced.
また、上記実施例においては、多値直交振幅変調を用い
た場合について述べたが、ＰＳＫ変調。Furthermore, in the above embodiments, a case was described in which multilevel orthogonal amplitude modulation was used, but PSK modulation is used.
ＦＭ変調、ＡＭ変調などほかの変調方式を用いることも
できる。Other modulation methods such as FM modulation and AM modulation can also be used.
また、上記実施例においては、テレビジョン信号をディ
ジタル符号化し、多値直交振幅変調して磁気記録媒体に
記録しているが、テレビジョン信号にかぎらずほかのデ
ィジタル符号を磁気記録媒体に記録する場合も上記構成
を用いることができ、さらに、磁気記録媒体にかぎらず
無線通信、マイクロウェーブ、衛星通信など他の伝送媒
体にも用いることができる。Furthermore, in the above embodiment, the television signal is digitally encoded, multi-level orthogonal amplitude modulated, and recorded on the magnetic recording medium, but not only the television signal but also other digital codes can be recorded on the magnetic recording medium. The above configuration can also be used in other cases, and can also be used not only for magnetic recording media but also for other transmission media such as wireless communications, microwaves, and satellite communications.
発明の効果
以上述べてきたように、本発明によれば、多値ディジタ
ル符号を、多値直行振幅変調して記録しているため、搬
送波近傍に、スペクトルが集中し、低域成分がな（なる
、よって、アジマス角をそれ、はど大きくせずに、べた
書きすることができる。Effects of the Invention As described above, according to the present invention, since a multi-level digital code is recorded by performing multi-level orthogonal amplitude modulation, the spectrum is concentrated near the carrier wave and low-frequency components are not present ( Therefore, it is possible to write solidly without increasing the azimuth angle.
また、多値ディジタル符号を用いているため、磁気記録
媒体の伝送Ｓ／Ｎが許容できる限り、周波数利用効率を
改善でき、また、磁気記録媒体の周波数劣化をたたみ込
み符号とみなして復号しているため、伝送Ｓ／Ｎの悪い
周波数高域部を強調せずに復号できる。また、バイアス
信号を加算して、多値直行振幅変調信号を記録している
ため、磁気記録媒体の再生歪の影響をあまりうけずに、
記録再生することができる。In addition, since a multilevel digital code is used, the frequency utilization efficiency can be improved as long as the transmission S/N of the magnetic recording medium is allowable, and frequency deterioration of the magnetic recording medium can be decoded by regarding it as a convolutional code. Therefore, it is possible to decode without emphasizing the high frequency region where the transmission S/N is poor. In addition, since the bias signal is added and a multi-level orthogonal amplitude modulation signal is recorded, it is not affected much by reproduction distortion of the magnetic recording medium.
Can be recorded and played.
第１図［８１，（ｂｌは本発明の一実施例を示す要部ブ
ロック図、第２図＋８）は４ビットディジタル信号の信
号配置図、第２図山）は４値デイジタル■およびＱ信号
の信号配置図、第２図（Ｃ１は１６値多値直交振幅変調
信号の信号配置図、第３図はバイアス信号を多値直行振
幅変調信号に加算したときの周波数アロケーション図、
第４図（ａｌは磁気記録媒体の周波数劣化特性図、第４
図（ｂｌは磁気記録媒体を伝送された！およびＱ信号の
周波数劣化特性図、第４図（Ｃ）はインパルス応答波形
図、第４図（ｄｉは！およびＱ信号をインパルス応答波
形とした場合の伝送波形図、第５図は■信号用（もしく
は、Ｑ信号用）ビタビ復号器の一実施例を示す要部ブロ
ック図である。
１・・・・・・Ａ／Ｄ変換器、２・・・・・・多値変換
器、３・・・・・・多値ＱＡＭ器、４・・・・・・加算
器、５・・・・・・バイアス信号発生器、６・・・・・
・ＲＥＣアンプ、７・・・・・・磁気ヘッド、８・・・
・・・磁気記録媒体、９・・・・・・ヘッドアンプ、１
０・・・・・・多値ＣＡＭ復調器、１１・・・・・・ビ
タビ復号器、１２・・・・・・Ｄ／Ａ変換器、１３・・
・・・・■信号用ビタビ復号器、１４・・・・・・■信
号用ビタビ復号器、２１・・・・・・パスメトリック計
算回路、２２・・・・・・周波数劣化情報回路、２３・
・・・・・ＡＣ３回路、２４・・・・・・パスメモリ回
路、３１・・・・・・ｎ値発生回路、３２゜３３．３４
．３５・・・・・・遅延素子、３６．３７゜３８．３９
・・・・・・乗算回路、４０・・・・・・加算回路。
代理人の氏名 弁理士 中尾敏男 はか１名第２図
７＝Ａｆｃ江ツ頌腟
Ｔ−１５ノｊ゛グＵッグ肩Δ【妃（
第３図
第４図
ｉＨ−’／Ｒａ ＊Fig. 1 [81, (bl is a block diagram of the main part showing one embodiment of the present invention, Fig. 2 +8) is a signal arrangement diagram of a 4-bit digital signal, Fig. 2 crest) is a four-value digital ■ and Q signal Fig. 2 is a signal arrangement diagram of a 16-value multi-value orthogonal amplitude modulation signal, Fig. 3 is a frequency allocation diagram when a bias signal is added to a multi-value orthogonal amplitude modulation signal,
Figure 4 (al is a frequency deterioration characteristic diagram of a magnetic recording medium, Figure 4
Figure (bl is a frequency deterioration characteristic diagram of the! and Q signals transmitted through a magnetic recording medium, Figure 4 (C) is an impulse response waveform diagram, Figure 4 (di is! and Q signal as impulse response waveforms) FIG. 5 is a block diagram of main parts showing an embodiment of a Viterbi decoder for ■ signals (or for Q signals). 1... A/D converter, 2... ...Multi-value converter, 3...Multi-value QAM device, 4...Adder, 5...Bias signal generator, 6...
・REC amplifier, 7...Magnetic head, 8...
... Magnetic recording medium, 9 ... Head amplifier, 1
0...Multi-level CAM demodulator, 11...Viterbi decoder, 12...D/A converter, 13...
...■Viterbi decoder for signals, 14...■Viterbi decoder for signals, 21...Path metric calculation circuit, 22...Frequency degradation information circuit, 23・
...AC3 circuit, 24...Pass memory circuit, 31...N value generation circuit, 32゜33.34
．． 35...Delay element, 36.37°38.39
...Multiplication circuit, 40...Addition circuit. Name of agent Patent attorney Toshio Nakao 1 person Fig. 2 7 = Afc Etsu vagina T-15 No.
Claims (2)
／Ｄ変換器と、前記ディジタル符号を、多値ディジタル
符号に変換する多値変換器と、前記多値ディジタル符号
を多値直行振幅変調する多値直行振幅変調器でもって、
磁気記録媒体に記録し、前記記録媒体からの再生信号を
、前記多値ディジタル符号に復調する多値直行振幅変調
復調器と前記磁気記録媒体の周波数劣化をたたみ込み符
号と見なして、前記多値ディジタル符号を、前記ディジ
タル符号に変換するビタビ復号器と前記ディジタル符号
を前記テレビジョン信号に変換するＤ／Ａ変換器でもっ
て、前記磁気記録媒体から、前記テレビジョン信号を再
生することを特徴とするディジタル磁気録画再生装置。(1) A converting television signals into digital codes
/D converter, a multi-value converter that converts the digital code into a multi-value digital code, and a multi-value orthogonal amplitude modulator that performs multi-value orthogonal amplitude modulation on the multi-value digital code,
A multi-value orthogonal amplitude modulation demodulator records data on a magnetic recording medium and demodulates a reproduced signal from the recording medium into the multi-value digital code, and a multi-value orthogonal amplitude modulation demodulator that records on a magnetic recording medium and demodulates the reproduced signal from the recording medium into the multi-value digital code. The television signal is reproduced from the magnetic recording medium using a Viterbi decoder that converts a digital code into the digital code and a D/A converter that converts the digital code into the television signal. A digital magnetic recording and playback device.
調信号に、磁気記録媒体の再生歪を最小にするバイアス
信号を加算するバイアス信号発生器とを具備するよう構
成したことを特徴とする請求項第（１）項記載のディジ
タル磁気録画再生装置。(2) A bias signal generator that adds a bias signal that minimizes reproduction distortion of the magnetic recording medium to the multi-value orthogonal amplitude modulation signal that is the output of the multi-value orthogonal amplitude modulator. A digital magnetic recording and reproducing apparatus according to claim (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3817088A JPH01211372A (en) | 1988-02-19 | 1988-02-19 | Digital magnetic picture recording and reproducing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3817088A JPH01211372A (en) | 1988-02-19 | 1988-02-19 | Digital magnetic picture recording and reproducing device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01211372A true JPH01211372A (en) | 1989-08-24 |
Family
ID=12517922
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3817088A Pending JPH01211372A (en) | 1988-02-19 | 1988-02-19 | Digital magnetic picture recording and reproducing device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01211372A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0465428A2 (en) * | 1990-07-05 | 1992-01-08 | Matsushita Electric Industrial Co., Ltd. | Digital modulated signal demodulator/decoder apparatus |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61287078A (en) * | 1985-06-13 | 1986-12-17 | Matsushita Electric Ind Co Ltd | Digital signal reproducing device |
-
1988
- 1988-02-19 JP JP3817088A patent/JPH01211372A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61287078A (en) * | 1985-06-13 | 1986-12-17 | Matsushita Electric Ind Co Ltd | Digital signal reproducing device |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0465428A2 (en) * | 1990-07-05 | 1992-01-08 | Matsushita Electric Industrial Co., Ltd. | Digital modulated signal demodulator/decoder apparatus |
| EP0465428A3 (en) * | 1990-07-05 | 1994-07-20 | Matsushita Electric Ind Co Ltd | Digital modulated signal demodulator/decoder apparatus |
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