JPS6364673A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To simultaneously record signals from plural channels by providing a means which frequency-divides an input signal, and a means which converts a frequency so that splitted channels can lie within recording band widths. CONSTITUTION:The input signal is put in banks 1 in four BPFs. Their passing band widths are the same, and their center frequencies are adjacent by the frequency difference between the passing band widths. The BPFs include DC components in their passing bands. The signals from the channels are given to a frequency conversion circuit 2, frequency-converted by a mixer, and simultaneously recorded on a magnetic tape 3 which independently has both a recording head and a recording track. Simultaneously a reproduction head with four channels reproduces the recorded magnetic tape 4, supplies signals to a frequency reverse conversion circuit 4, which returns them to signals with their original frequency bands. The obtained reproduction signals from four channels are amplitude-added 5, and outputted as reproduction signals.

Description

DETAILED DESCRIPTION OF THE INVENTION Strategy 1 The present invention relates to a recording/reproducing apparatus, and particularly to a recording/reproducing apparatus using a recording medium such as a magnetic tape.

BACKGROUND OF THE INVENTION Conventionally, one method for expanding the recording frequency bandwidth in a recording/reproducing apparatus is to increase the relative speed between the recording medium and the recording head. When the speed of the recording medium is increased, the recording density of the recording medium naturally decreases, resulting in a reduction in recording time, and the increase in the relative speed between the recording medium and the recording head causes various operations to be delayed. This has the disadvantage that control becomes complicated.

OBJECTS OF THE INVENTION An object of the present invention is to provide a recording/reproducing apparatus that can increase the recording frequency bandwidth without increasing the relative speed between the recording medium and the recording head.

Composition of the Invention The recording device according to the present invention is a recording device capable of simultaneously recording multiple channels, and includes means for frequency-dividing an input signal to be recorded into multiple channels with a frequency bandwidth equal to or less than the recording bandwidth of the device. , a means for converting the frequency of each of the plurality of frequency-divided channels so that it falls within the recording bandwidth, and the signals of the plurality of frequency-converted channels are simultaneously recorded on the recording medium. It is a feature.

The recording and reproducing apparatus according to the present invention is a recording and reproducing apparatus capable of simultaneously recording and reproducing multiple channels, and on the recording side, an input signal to be recorded is transmitted to multiple channels with a frequency bandwidth equal to or less than the recording bandwidth of the apparatus. means for frequency division; frequency conversion means for converting the frequency of each of the frequency-divided channels so as to fall within the recording bandwidth; and simultaneous recording of the frequency-converted signals of the plurality of channels on a recording medium. on the reproduction side,
The present invention is characterized in that it includes means for returning each simultaneously reproduced channel from the recording medium to the frequency before conversion by the frequency converting means, and means for deriving the amplitude sum of each channel thus obtained.

1 dust 1 Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, and is an example in which the number of channels is four. An input signal to be recorded is input to a filter bank circuit 1 and divided into four channels of signals having different frequency bands. The frequency characteristics of this filter bank circuit 1 are shown in FIGS.
As shown in d), the frequency bandwidth of each channel is set to be less than the recording bandwidth of the device, and each passband is selected so as to be adjacent to each other. That is, four BPFs (band pass filters) are used, and the passband width of each BPF is selected to be equal and substantially equal to the recording frequency bandwidth,
Furthermore, it is assumed that the center frequencies of each pass band are adjacent to each other with a frequency difference corresponding to the width of the pass band. It is assumed that the BPF of channel 1 is designed to include up to the DC component within its pass band.

The signals of the four channels frequency-divided in this way are supplied to the frequency conversion circuit 2. This frequency conversion circuit 2
The output frequency band characteristics of the device are as shown in Figures 3(a) to (d), and it has a function of converting each input channel frequency to a frequency within the recording bandwidth of the device. This is realized by a mixer circuit.

Each frequency-converted channel signal is sent to a magnetic tape device 3.
The magnetic tape device 3 used here has four channels of recording heads and four independent recording tracks. The magnetic tape recorded in this manner is also simultaneously reproduced by the four-channel reproduction head, and the reproduction signal of each channel is supplied to the frequency inversion circuit 4.

This frequency inverse conversion circuit 4 performs a conversion operation opposite to that of the frequency conversion circuit 2, and therefore reproduces each channel having the frequency bands shown in FIGS. 3(a) to 3(d). The signal will be converted back into a signal having the frequency bands shown in FIGS. 2(a)-(d). The four channels of reproduced signals obtained in this manner are summed by the imaging width in an adding circuit 5, and are output as reproduced signals.

FIG. 4 shows the input/output signal waveforms of the filter bank circuit 1, where (a> indicates the waveform when a pulse signal is input,
(b) to (e) respectively show the output waveforms of the BPFs of channels 1 to 4, which are frequency components in respective bands of the input signal (a).

By doing this, all the frequency components of the input signal to be recorded will fall within the recording bandwidth, making it possible to substantially expand the recording bandwidth without increasing the relative speed between the recording medium and the recording head. It becomes.

Although the above embodiment has been described as having four channels, the present invention is not limited to this, and it is clear that the recording medium is not limited to magnetic tape, but other media may also be used.

As described in detail, according to the present invention, an input signal to be recorded is divided into a plurality of frequency components, and the frequency band of each frequency component signal is set to be less than or equal to the recording bandwidth. This has the effect of making it possible to sufficiently record. During playback, the recording frequency bandwidth is expanded by the number of frequency divisions (the number of channels) times the frequency bandwidth of the device itself by recombining the signals that have been divided into multiple frequency components and recorded. become.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment of the present invention, Fig. 2(a) -
(d) is a diagram showing the band characteristics of each channel BIF of the filter bank circuit, Figures 3 (a) to (d) are diagrams showing the output band characteristics of the frequency conversion circuit for each channel, and Figure 4 (a)
) is a diagram showing an example of the input signal waveform of the filter bank circuit,
FIGS. 4(b) to 4(e) are diagrams showing each channel output waveform of the filter bank circuit for the input signal of FIG. 4(a). Explanation of symbols of main parts 1... Filter bank circuit 2... Frequency conversion circuit 3... Magnetic tape device 4... Frequency inverse conversion circuit 5... ...Addition circuit

Claims (2)

[Claims] (1) A recording device capable of simultaneous recording of multiple channels, comprising means for frequency-dividing an input signal to be recorded into multiple channels with a frequency bandwidth equal to or less than the recording bandwidth of the device; means for converting the frequency of each of the channels so that it falls within the recording bandwidth;
A recording device characterized in that signals of a plurality of frequency-converted channels are simultaneously recorded on a recording medium. (2) A recording/playback device capable of simultaneous recording and playback of multiple channels, including means for frequency-dividing the input signal to be recorded into multiple channels with a frequency bandwidth equal to or less than the recording bandwidth of the device on the recording side. , comprising frequency converting means for converting the frequency of each of the plurality of frequency-divided channels so that it falls within the recording bandwidth, and means for simultaneously recording the signals of the plurality of frequency-converted channels on a recording medium, On the reproduction side, the recording medium includes means for returning each simultaneously reproduced channel from the recording medium to the frequency before conversion by the frequency conversion means, and means for deriving the amplitude sum of each channel obtained in this way. A recording/playback device for