JPS6032243B2 - Analog information recording and playback method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an analog information recording and reproducing method in which a plurality of analog signals are sequentially sampled and multiplexed in a time-division manner, and information on any channel can be accessed at approximately the same speed. The present invention relates to an information recording and reproducing method suitable for an announcement system in which when there is a request to call up one piece of audio information out of a plurality of pieces of audio information, it is necessary to output all pieces of information in approximately the same amount of time.

Conventionally, when recording a large number of analog signals on a recording medium such as a magnetic drum or magnetic tape, there are two methods: a multi-track method in which each channel's analog signal is assigned to one recording track, and the other is a multi-track method in which each channel's analog signal is sequentially serially recorded. There is a method for recording. Although the multi-track system has the advantage that the analog signals of this channel can be accessed at a constant speed, it requires a wide magnetic tape or magnetic drum as a recording medium, which is special and expensive.

Additionally, a head moving mechanism or multiple heads are required. If the head is moved, the mechanism will be complicated, expensive, and unreliable.If the head is moved, the mechanism will be complicated, and reliability will be poor.If the head is moved, the mechanism will be difficult to manufacture as the number of channels increases, and the product will become expensive. be. Furthermore, if the analog signals of each channel are recorded sequentially and serially like in a normal magnetic tape device, there will be a large difference in access time depending on the channel, and the access time for the last channel will be extremely long. Put it away.

Therefore, such a method is not suitable for an announcement system in which, for example, when there is a request to call up any information among a plurality of audio information, all information must be output at almost the same time. In other words, this is because it takes a very long waiting time from when the last voice information is called up to when it is actually output. The purpose of the present invention is to eliminate the momme point of the prior art as described above, to record multiple channels of analog signals using at most several tracks, and to immediately read out information corresponding to the request when there is a read request. The output can be serious,
It is an object of the present invention to provide an analog information recording and reproducing method that can be easily and inexpensively converted into a device.

That is, the present invention records multiplexed analog information in which a plurality of analog signals are sequentially sampled in a time-division manner and arranged in series on one track of a recording medium, and also records the multiplexed analog information on one track of a recording medium. A synchronization signal that is synchronized with the analog information is also recorded, and after reading and amplifying this information through a playback head, among the reproduced synchronization signals,
A sampling pulse is created by extracting only the component corresponding to one channel specified by an externally applied channel selection signal, and the sampling pulse is used to open and close one analog gate to reproduce multiple analog information. This is an analog information recording and reproducing method in which only one type of analog signal corresponding to a designated channel is sampled and demodulated.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

This embodiment is an example in which a magnetic tape is used as a recording medium, two tracks are used, a plurality of audio signals are recorded on one track, and a synchronization signal synchronized with the audio signal is recorded on the other track. This is a case where audio information of a channel is recorded and played back. As shown in FIG. 1a, b, and c, three types of audio signals, channel-1, channel-2, and channel-3, are recorded. Such an audio signal is sampled with a synchronous signal of a constant frequency as shown in d. That is, the first pulse of the synchronization signal samples the audio signal of channel-1, the second pulse samples the audio signal of channel-2, and the third pulse samples the audio signal of channel-3. sample. Similarly, channel-1 is sampled again in the fourth pulse, channel-2 is sampled in the fifth pulse, channel-3 is sampled in the sixth pulse, and so on. The amplitudes of the audio signals of each channel when sampled in this way are respectively channel-1:a, . a・2a. ... aIN channel-2: aZ mo242... a2N channel-3: a red
a32a range. ...a3N.

When the obtained sampling output signals are arranged serially in the order of sampling, the following multiplexed audio information is obtained. all, aa, a31, a・2, a22, a32,
a・3, &2, a33.・・aIN'a2N' a3
N The multiplex audio information obtained in this way is recorded on one track 2 of the magnetic tape as shown in e, and the synchronization signal corresponding to the multiplex audio information is recorded on the same magnetic tape. recorded on another track 3.

To reproduce the three-channel audio information recorded on the magnetic tape in this manner, a circuit as shown in FIG. 2 may be used, for example.

Information recorded on two tracks 2 and 3 on a magnetic tape 1 is read out using a two-track fixed head 4.

The read audio information and synchronization signal are each amplified by sense amplifiers 5a and 5b, and then the synchronization signal is sent to a control circuit 6 and a sampling pulse generator 7, and these two circuits receive a channel selection signal given from the outside. A sampling pulse is created by extracting only the synchronization signal component corresponding to the channel specified by . On the other hand, the amplified multiplex audio signal is coupled to an analog switch 8, and the on/off state of the analog switch 8 is controlled by the sampling pulse. The output signal from the analog switch 8 is demodulated by a demodulation circuit 9, amplified by a power amplifier 10, and outputted as audio from a speaker 11. For example, to obtain the playback output of channel-1, do as follows.

The control circuit 6 and sampling pulse generator 7 select the first, fourth, and seventh synchronizing signals by a channel selection signal (in this case, specifying channel -1) given from the outside.
The (10 $h)th, . . . , (10 $h) th pulses are extracted to obtain the channel-1 sampling pulse as shown in FIG. 1f. When the analog switch 8 is controlled using this sampling pulse and the readout output of the multiplexed audio information is sampled, the following audio signal is obtained. a,,,a,2,a,3...
a, N This becomes the sampled channel-1 audio signal as shown by the solid line in FIG. 1g.

If such a sampled audio signal of channel-1 is demodulated by the demodulation circuit 9, a reproduced output signal as shown by the broken line in the figure is obtained.If this is power amplified and sent to the speaker 1, the signal of channel-1 is demodulated. Audio information corresponding to is played. As described above, according to the present invention, since a plurality of pieces of audio information are multiplexed and recorded, the difference in access time between channels is {(period of synchronization signal) x (total number of channels - 1
)}, and in practice it can be assumed that all channels can be accessed at the same speed.

Therefore, the present invention is particularly suitable for a system that needs to immediately output any information when there is a request to call up any information among a plurality of pieces of audio information.

Examples of such systems include an OK monitor announcement system for automobiles, an announcement system for telephone guidance, an announcement system for station staff, an announcement system for trains, an announcement system for road guidance, and various other information services. There is an announcement system, etc. Although a preferred embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various modifications can be made within the scope of the claims. Of course, it also includes

The recording medium may be a magnetic drum, a magnetic disk, a magnetic card, etc. in addition to a magnetic tape. It is also possible to record audio information and synchronization signals on one recording track.
It is also possible to record audio information in a distributed manner over two or more tracks. The repetition frequency of the synchronization signal for time division is 1
The value may be such that one syllable, for example "a", is sampled with multiple pulses, or one pulse may be assigned to one syllable. In this case, as the number of audio information channels increases, the syllables become longer, so if each sound is sustained to create an echo effect, natural reproduced sound can be obtained. Further, there is no particular restriction on the number of channels of audio information. Further, although the above embodiment records audio information, it goes without saying that the present invention can also be applied to recording and reproducing analog information other than audio information. Since the present invention is a method for recording and reproducing analog information configured as described above, in response to an external read request,
It is possible to immediately access and output any one of the many recorded analog information, and since one type of synchronization signal is sufficient, the synchronization signal generation and
The recording circuit and the reproducing/extracting circuit can be simplified, and since the output information is always one type, the output can be controlled with one analog gate, which has excellent effects such as extremely simplifying the device configuration.

Therefore, the present invention is extremely effective particularly for systems that output audio information. In addition, because only one track or several tracks are used, standard narrow magnetic tapes and magnetic cards can be used, and playback can be performed with a fixed head for at most several tracks, which requires a complicated head movement mechanism and multiple heads that are difficult to manufacture. This eliminates the need for the system, which has the advantage that it has a simple structure and is easy to manufacture, making it possible to construct a system that is inexpensive and highly reliable.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of the operating principle of the method of the present invention, and FIG. 2 is a block diagram showing an example of a reproducing circuit.

1...Magnetic tape, 2...Audio information track, 3
... Synchronization signal track, 4 ... Playback head, 5a, 5b ... Sense amplifier, 6 ...
...Control circuit, 7...Sampling pulse generator, 8...Analog switch, 9...
Demodulation circuit, 10 power amplifier, 11...speaker.

Figure 2 Figure 1

Claims (1)

[Claims] 1 Multiplex analog information, which is obtained by sequentially sampling a plurality of analog signals in a time-division manner and then serially arranged, is recorded on one track of a recording medium, and synchronized with the multiplex analog information on the recording medium. A synchronization signal is also recorded, and after reading and amplifying this information through a reproduction head, only the component corresponding to one channel specified by a channel selection signal given from the outside is extracted from the reproduced synchronization signal. A sampling pulse is created, and the sampling pulse is used to open and close one analog gate to sample and demodulate only one type of analog signal corresponding to a designated channel from the reproduced multiplex analog information. Analog information recording and playback method.