JP2003060440A - Analog data communications equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an analog data communications equipment which can simply and legally communicate and can store, retransmit and the like analog data without the need for a complicated circuit, such as a compression technique or the like of the analog data, irrespective of the presence or absence of a regularity and which has high reliability of a communication. SOLUTION: The analog data communication equipment for communication the analog data comprises at least a means for FM-modulating the analog data, a means for waveform shaping an FM-modulated signal to a rectangular wave, and a means for converting the waveform-shaped signal into a digital signal synchronously with a certain predetermined reference clock signal. Thus, the equipment digitally modulate the digital signal and then retransmits the modulated signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for communicating analog data.

[0002]

2. Description of the Related Art In analog data communication, analog data is modulated by some means, converted to a predetermined frequency and transmitted, and the receiving side frequency-converts the received data and further demodulates it back into analog data for transmission / reception. Complete.

As a method of modulating analog data, FM modulation (frequency modulation), AM modulation (amplitude modulation), PM modulation (phase modulation), etc. are generally used, and are widely used in television, radio and the like.

Further, a method of converting analog data into digital data, modulating and demodulating the digital data, and transmitting and receiving is also widely used.

As a method of converting analog data into digital data, a method of sampling the analog data at a constant cycle and quantizing the sampled analog data with a predetermined data length is used. A for modulation and demodulation at this time
SK modulation (amplitude shift keying), FSK modulation (frequency shift keying), BPSK modulation (two-phase phase shift keying), QPSK modulation (four-phase phase shift keying) and the like are used.

Further, when the analog data is converted into digital data and the data amount of the digital data is large, a compression technique is used to reduce the data amount and the method of transmitting and receiving is also widely used.

On the other hand, a standard is defined depending on the frequency used for communication, and it is necessary to conform to this standard during communication. If it does not conform, it is illegal and cannot be used. 2.4G band standard
Taking ARIB STD-T66 as an example, the communication method is for transmitting digital signals, and the one-way communication method, simplex method, half-duplex method or duplex method, and the contents of communication are digitized. It is determined that the frequency band used for mainly transmitting data signals is 2400 MHz or higher and 2483.5 MHz or lower. Furthermore, the frequency bandwidth occupied during communication is set to 26 MHz or less.

[0008]

SUMMARY OF THE INVENTION When analog data is communicated by analog modulation, that is, FM modulation, AM modulation, PM modulation, etc., the frequency band that can be communicated by analog modulation is limited. Frequently the frequency band cannot be legally used. 2.4G band (standard ARIB
STD-T66) would be illegal. Further, in the case of analog modulation, data is often limited to real-time transmission / reception, and in many cases it is not possible to comply with requests for data storage, retransmission, and the like. This means that in data communication, reliable data communication cannot be performed, in other words, the reliability of communication is poor.

Further, in the method of converting analog data into digital data and performing communication, the frequency band occupied during communication becomes wide due to the sampling period for converting into digital data and the data length to be quantized, so that legal communication cannot be performed. There are cases. If the frequency band of analog data is 0-5
If it is MHz, the sampling frequency when converting to digital data requires 10 MHz or more,
When the data length to be quantized is 8 bits, the communication speed of digital data is 80 Mbps or more. When this digital data is to be modulated and transmitted, the occupied frequency bandwidth becomes 160 MHz or more in BPSK modulation and 80 MHz or more in QPSK modulation, resulting in 2.4 G band (standard
ARIB STD-T66) is not legally satisfactory.

Further, if the above digital data is transmitted by another digital modulation method such as multi-level QAM modulation or OFDM modulation, the occupied bandwidth can be narrowed, but the modulation / demodulation circuit becomes complicated and the reliability of communication is further increased. It gets worse.

There is also a method in which digital data converted into digital is compressed by a compression technique to reduce the amount of data, that is, the occupied frequency bandwidth is narrowed to perform communication, but the circuit for compression is complicated and a large-scale circuit configuration is required. turn into.

Further, if the analog data is a signal consisting of a certain pattern, such as a video signal, the amount of data after compression can be reduced, but in the case of analog data having no regularity, In many cases, it is difficult to compress, the amount of data is small, in other words, it is difficult to narrow the occupied frequency bandwidth.

In view of the above problems, the present invention can easily and legally communicate analog data regardless of whether it has regularity without requiring a complicated circuit such as a compression technique. It is an object of the present invention to provide an analog data communication device capable of storing and retransmitting data and having high communication reliability.

[0014]

In an apparatus for communicating analog data, at least means for FM-modulating analog data, means for waveform-shaping an FM-modulated signal into a rectangular wave, and a predetermined waveform-shaping signal. Having a means for converting into a digital signal in synchronization with the reference clock signal of
An analog data communication device for digitally modulating the digital signal and transmitting / receiving the digital signal is used.

In a device for communicating analog data,
At least means for FM-modulating analog data;
A means for waveform-modulating the modulated signal into a rectangular wave, a means for converting the waveform-shaped signal into a digital signal in synchronization with a predetermined reference clock signal, and means for transmitting / receiving the digital signal after digital modulation are provided. The transmitting side and the receiving side have a sampling signal which is the same as the reference clock signal or an integral multiple of the reference clock signal, the digital signal is sampled by the sampling signal, and the internal data processing is performed by the obtained sampling. It is an analog data communication device that uses later signals.

[0016]

1 is a block diagram showing a transmitting side of a first embodiment of an analog data communication apparatus according to the present invention, and FIG. 2 is a time chart for explaining the operation of the first embodiment of the present invention. 2 shows waveforms at points A to E in FIG.
The transmission side of the analog data communication device includes an amplifier 11, an FM modulator 12, a waveform shaper 13, a clock synchronizer 14, a reference clock 15, a BPSK modulator 16, an OSC 17,
The power amplification unit 18 and the ANT unit 19 are included.

The analog data to be transmitted is first input to the amplification section 11 and amplified to a predetermined signal level. The amplified signal is input to the FM modulator 12 and FM-modulated. The FM-modulated signal is input to the waveform shaping section 13 and converted into a rectangular wave. The conversion method can be easily realized by comparing the FM-modulated signal with the 0 cross point by a comparator or the like. Next, the waveform-shaped signal is input to the clock synchronization unit 14. The reference clock from the reference clock unit 15 is also input to the clock synchronization unit 14. The clock synchronization unit 14 samples and outputs the waveform-shaped signal at the rising or falling of the input reference clock. In this way, a digital signal synchronized with the reference clock from the reference clock unit 15 and having analog data information can be obtained. The obtained digital signal is BPSK-modulated by the local oscillation signal having the same frequency as the communication frequency obtained from the OSC unit 17 in the BPSK modulation unit 16 and then transmitted from the ANT unit 19 via the power amplification unit 18.

At this time, the FM modulation frequency may be about twice the frequency band of the analog data, and the reference clock frequency may be about 50 times the FM modulation frequency. That is, if the frequency band of analog data is 0 to 5 MHz, the FM modulation frequency is 10 MHz and the reference clock frequency is 500 MHz. Further, the FM modulation frequency and the reference clock frequency depend only on the frequency band of analog data, and do not depend on the regularity of analog data.

In this way, analog data can be easily converted into digital data and transmitted. That is, by using digital data, it is possible to transmit in a frequency band in which only digital data is permitted to be transmitted.

The occupied frequency bandwidth is twice the FM modulation frequency, that is, 20 MH because BPSK modulation is performed.
z, the occupied frequency bandwidth becomes narrow, and it is a legally sufficient range in the 2.4 G band (standard ARIB STD-T66). Of course, if the frequency band of analog data is narrow, it is possible to lower the FM modulation frequency and the reference clock frequency, and a smaller amount of data, that is, a narrow occupied frequency bandwidth is required.

The receiving side receives the transmitted signal,
By performing FM demodulation after BPSK demodulation, it is possible to restore the original analog signal.

Alternatively, since the frequency band of the original analog signal is far from the FM modulation frequency, if the received signal is FM demodulated as it is and only the frequency band of the original analog signal is extracted by a filter or the like, the original analog signal can be obtained. Can be returned to.

FIG. 3 is a block diagram showing the transmitting side of the second embodiment of the analog data communication device according to the present invention, and FIG. 4 is a block diagram showing the receiving side of the second embodiment of the present invention. On the transmission side of the analog data communication device, an amplification unit 31, an FM modulation unit 32, a waveform shaping unit 33, a clock synchronization unit 34, a reference clock unit 35, a shift register unit 36, a latch unit 37, a frequency dividing unit 38, a CPU unit 39, Memory unit 40, BPSK modulation unit 41, OSC unit 42, power amplification unit 43, ANT unit 44
It is composed of The receiving side of the analog data communication device has an ANT section 51, a power amplification section 52, and a BPSK demodulation section 5.
3, shift register section 54, latch section 55, reference clock section 56, frequency division section 57, CPU section 58, memory section 59,
It is composed of an FM demodulation unit 60.

First, the operation on the transmitting side will be described. Similar to the first embodiment, the analog data to be transmitted is first input to the amplification unit 31, amplified to a predetermined signal level, and then F
FM modulation is performed by the M modulator 32. The FM-modulated signal is converted into a rectangular wave by the waveform shaping unit 33, and the clock synchronization unit 34 obtains a digital signal that is synchronized with the reference clock from the reference clock unit 35 and has analog data information.

The obtained digital signal is input to the shift register section 36, serial-parallel converted by the reference clock from the reference clock section 35 to obtain 8-bit parallel data, and input to the latch section 37. Divider 38
A latch pulse having a frequency of ⅛ of the reference clock is obtained from the reference clock unit 35 and input to the latch unit 37 and the CPU unit 39. As a result, the serial-parallel converted 8-bit parallel data can be taken into the CPU section 39.

In the CPU section 39, the fetched 8 bits
The parallel data is stored in the memory unit 40, and when transmission is necessary, the data stored in the memory unit 40 is parallel-serial converted and output. The output signal is output to the OSC section 4 by the BPSK modulation section 41 as in the first embodiment.
2 is BPSK-modulated with a local oscillation signal having the same frequency as the communication frequency obtained from A.
It is transmitted from the NT unit 44.

Next, the operation on the receiving side will be described. ANT part 5
The signal received at 1 is transmitted to the BPS through the power amplifier 52.
It is input to the K demodulation unit 53. The BPSK demodulated signal is input to the shift register unit 54, serial-parallel converted to obtain 8-bit parallel data by the reference clock from the reference clock unit 56 having the reference clock of the same frequency as the transmitting side, and the latch unit 55 receives the parallel data. input. 1/1 of the reference clock from the frequency divider 57 to the reference clock 56
The latch pulse of the frequency of 8 is obtained, and the latch unit 55 and CP
Input to U section 58. As a result, the serial-parallel converted 8-bit parallel data can be taken into the CPU unit 59.

In the CPU section 58, the fetched 8 bits
When it is necessary to store the parallel data of the above in the memory unit 59 and restore the original analog signal, the data stored in the memory unit 59 is parallel-serial converted and output. The output signal is input to the FM demodulation unit 60 and demodulated into the original analog signal.

If the analog data to be transmitted has the same frequency band as in the first embodiment, the speed at which the analog data is taken into the CPU section 39 (58) is 500 MHz / 8 = 62.5 MHz. In the present embodiment, the length of the parallel data is set to 8 bits, but it goes without saying that the data length can be set to any value according to the performance of the CPU section 39 (58), that is, any value.

In this way, an analog data communication device capable of storing analog data can be realized. If analog data can be stored, data can be retransmitted when communication is abnormal, and communication reliability is improved.

Needless to say, the present invention can be used for various purposes such as voice data communication, video data communication, etc. because it can store analog data regardless of the type of analog data.

The FM modulation frequency and the reference clock frequency are
An appropriate value may be set according to the occupied frequency bandwidth used for communication, the frequency band of analog data to be transmitted, the processing capacity of the CPU, etc., and the value is not limited to the value in the embodiment.

In the embodiment, modulation / demodulation of digital data is performed by BPSK modulation / demodulation.
K modulation, demodulation, FSK modulation, QPSK modulation, etc.), and the present invention is not limited to BPSK modulation.

Further, although the transmitting side and the receiving side are separated in the present embodiment, it is also possible to integrate them to utilize bidirectional communication by utilizing FDMA (frequency division multiple access) and TDMA (time division multiple access). is there

Further, this embodiment is based on the 2.4 G band (standard
Although it has been described on the premise that it is used in ARIB STD-T66), it is not limited to the use in the 2.4 G band, and can be easily used in conformity with the standard in other frequency bands.

[0036]

According to the present invention, analog data can be converted into digital data without requiring a large-scale circuit, and analog data communication in a frequency band where only digital data communication is permitted. Can be legally realized.

It becomes possible to narrow the occupied frequency bandwidth when communicating even analog data having a wide frequency band,
Analog data that was difficult to communicate can be easily communicated.

Regardless of the regularity of analog data, it is possible to communicate with a small amount of data, that is, with a narrow occupied frequency bandwidth, and it is possible to easily communicate analog data for which compression technology cannot be used.

According to the second aspect of the present invention, since analog data can be stored, retransmitted, etc., an analog data communication device having high communication reliability can be provided.

According to the invention of claim 2, since analog data can be stored and retransmitted, it can be utilized for various purposes.
Product design flexibility is increased.

[Brief description of drawings]

FIG. 1 is a block diagram showing a transmitting side according to a first embodiment of the present invention.

FIG. 2 is a time chart explaining the operation of the first embodiment of the present invention.

FIG. 3 is a block diagram showing a transmitting side according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a receiving side according to a second embodiment of the present invention.

[Explanation of symbols] 11 Amplifier 12 FM modulator 13 Wave shaping section 14 Clock synchronization section 15 Reference clock section 16 BPSK modulator 17 OSC Department 18 Power amplifier 19 ANT Department 31 Amplifier 32 FM modulator 33 Wave shaping section 34 Clock synchronization section 35 Reference clock section 36 Shift register section 37 Latch 38 frequency division 39 CPU section 40 memory 41 BPSK modulator 42 OSC Department 43 Power amplifier 44 ANT Department 51 ANT Department 52 Power amplifier 53 BPSK demodulator 54 shift register 55 Latch 56 Reference clock section 57 frequency division 58 CPU 59 memory 60 FM demodulator

Claims (2)

[Claims] 1. A device for communicating analog data, comprising:
At least means for FM-modulating analog data;
A means for waveform-modulating the modulated signal into a rectangular wave and a means for converting the waveform-shaped signal into a digital signal by synchronizing it with a predetermined reference clock signal are provided. Characteristic analog data communication device. 2. A device for communicating analog data, comprising:
At least means for FM-modulating analog data;
A means for waveform-modulating the modulated signal into a rectangular wave, a means for converting the waveform-shaped signal into a digital signal in synchronization with a predetermined reference clock signal, and means for transmitting / receiving the digital signal after digital modulation are provided. The transmitting side and the receiving side have a sampling signal which is the same as the reference clock signal or an integral multiple of the reference clock signal, the digital signal is sampled by the sampling signal, and the internal data processing is performed by the obtained sampling. An analog data communication device characterized in that it is performed with a later signal.