JPH09189764A - Submersible radio signal transmission method and system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen the work for preventing generation of mutual interference by transmitting a signal at a predetermined transmission period depending on an identification code affixed to a radio signal and discarding the signal on the receiving side except those addressed thereto determined by the identification code. SOLUTION: An A/D converter 41 converts an inputted measurement signal to a digital signal and a code setting section 43 affixes a code indicative of an output 42, as an identification code, to the measurement signal. A CPU 45 delivers the output from setting section 43 and the periodic signal of a ROM 44 to a transmission circuit 46. The circuit 46 converts them sequentially into analog signals which are outputted, as a radio transmission signal, at the carrier frequency of an oscillator 47. On the other hand, the transmission signal received through an oscillator 51 is amplified through an amplifier 52 and converted into a digital signal which is then separated, at a code separating section 53, into identification data and a measurement data before being delivered to a CPU 54. When the identification code matches the code indicative of an output 56, the CPU 54 accepts the measurement data as a valid data otherwise discard the measurement data as an invalid data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater radio signal transmission system used in a fish finder or the like, and more particularly to an underwater radio signal capable of preventing mutual interference when a single frequency signal is used. Regarding transmission method.

[0002]

2. Description of the Related Art FIG. 3 is a diagram for explaining a conventional radio signal transmission system in water. FIG. 3 (a)
The signal transmitted as shown in (1) was composed of a periodic signal 61 and measurement data 63. The periodic signal 61 is periodically transmitted prior to the transmission of the measurement data 63 to indicate its transmission timing, and these transmission periods are as shown in FIG.
As shown in (b), it is constant regardless of the used frequency.

The above-mentioned signal transmission in water is performed by ultrasonic waves, but if radio signal transmissions of the same frequency band are carried out at a short distance, they interfere with each other. Therefore, in order to prevent this, radio signal transmissions are carried out. It is supposed that the frequency of the signal to be used is changed so as to be different for each transceiver.

[0004]

As described above, in order to prevent the occurrence of mutual interference, it has been conventionally used to change the frequency to be different for each transmitter and receiver at a short distance.
For this reason, when using a transceiver at a short distance, check the frequency used by other transceivers, and if the confirmed frequency matches the used frequency, you must change the used frequency. The first problem is that it takes time and effort.

Further, since usable frequencies are limited, the same frequency may be unavoidably used even at a distance where mutual interference is expected to occur.
In this case, the measured data of the part where mutual interference occurs cannot be used by either transmitter or receiver, but in the past, the signal transmission cycle was constant regardless of the transmission frequency. A second problem is that if unusable measurement data is generated due to interference, that state will continue.

The second problem is particularly problematic when the FM wave is used as the transmission frequency because the FM wave causes mutual interference in which a weak level signal is canceled by a strong level signal even if the used frequency is different. .

The present invention has been made in view of the problems of the above-described conventional techniques, and can reduce the work required for preventing the occurrence of mutual interference, and It is an object of the present invention to realize a method and system for transmitting a radio signal in water that can prevent the state from continuing even if it occurs.

[0008]

According to the method of transmitting a radio signal in water of the present invention, an identification code is added to a radio signal on the transmitting side and the radio signal is transmitted at a predetermined transmission cycle according to the identification code. The receiving side is characterized by confirming the identification code to see if it is addressed to itself, and discarding anything other than to itself.

The underwater radio signal transmission system of the present invention is an underwater radio signal transmission system for transmitting underwater by a radio signal, and the transmitting side converts the transmission data into a digital signal. A D converter, an identification code assigning unit that assigns a predetermined identification code to the digital signal converted by the A / D converter, and a transmission cycle that is different for each identification code, and the identification number assigned by the identification code assigning unit is stored. Transmission cycle storage means for outputting a signal indicating a transmission cycle corresponding to the code, and transmission control means for outputting the digital signal to which the identification code is added by the identification code adding means at the transmission cycle indicated by the output of the transmission cycle storage means. And transmission means for converting the output of the transmission control means into a wireless transmission signal and outputting the same, and the receiving side receives the signal for converting the wireless transmission signal into a digital signal. Stage, code separating means for separating the identification code and transmission data from the digital signal converted by the receiving means, reception identification code confirming means for outputting a signal indicating the identification code to be received, and each identification code to be received. A reception cycle storing means for storing different reception cycles,
It is confirmed whether the identification code output by the code separation means matches the identification code to be received indicated by the reception identification code confirmation means output. If they match, the identification code is stored in the reception cycle storage means in correspondence with the identification code. It is characterized in that it is provided with a reception control means for performing a reception operation in a certain reception cycle and not performing a reception operation if they do not match.

In this case, the transmitting means may transmit the transmission data and the identification code as a radio transmission signal having a different frequency.

[Operation] In the present invention configured as described above, since the received data is selected according to the provided identification code, the same frequency signal is used as a signal for each type of identification code. You can Also, since multiple transmission cycles are different depending on the assigned identification code, even if mutual interference occurs, the mutual interference that occurs over time is resolved and the interference state does not continue. Becomes

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. FIG. 1A shows a transmitter for inputting data measured by a measuring device and outputting it as a wireless transmission signal.
FIG. 1B shows the configuration of the receiving unit. Further, FIG. 2 is a diagram showing a transmission signal used in this embodiment.

First, the structure of the transmission unit in this embodiment will be described. As shown in FIG. 1 (a), the transmitter is an A / D
The converter 41, the DIP switch 42, the code setting unit 43 that constitutes the identification code assigning unit together with the DIP switch 42, the ROM 44 that is the transmission cycle storing unit, the CPU 45 that is the transmission controlling unit, the transmission circuit 46 and the vibrator 47 that configure the transmitting unit. It consists of

The A / D converter 41 inputs the measurement signal, converts it into a digital signal, and outputs it to the code setting section 43. A predetermined code is set by the user on the DIP switch 42, and a signal indicating the set code is output. Further, the ROM 44 stores a transmission cycle corresponding to each code that can be set in the DIP switch 42.

The code setting unit 43 adds the code indicated by the output of the DIP switch 42 to the input of the A / D converter 41 as an identification code and sends it to the CPU 45, and the output of the DIP switch 42 indicates to the ROM 44. Output the code. ROM that accepts the above input
Reference numeral 44 outputs the stored transmission cycle corresponding to the code indicated by the output of the DIP switch 42 to the CPU 45. CP
In U45, the output of the code setting unit 43 is sent to the transmission circuit 46 together with the periodic signal according to the transmission period indicated by the ROM 44 output. The transmission circuit 46 is a D / A converter (not shown)
Built-in, which sequentially converts the output of the CPU 45 into an analog signal. The output of the transmission circuit 46 is applied to the oscillator 47, and is output as a wireless transmission signal as shown in FIG. 2 with the oscillation frequency of the oscillator 47 as the carrier frequency.

The signal shown in FIG. 2 is composed of a periodic signal 1 output at a period determined by the output of the ROM 44, an identification code 2 and measurement data 3, and the carrier frequency is a constant determined by the oscillation frequency of the oscillator 47. However, the transmission cycle is variable according to the output of the ROM 44.

Next, the structure of the receiving unit in this embodiment will be described. As shown in FIG. 1B, the receiving unit includes a vibrator 51 and an amplifier 5 that constitutes a receiving means together with the vibrator 51.
2. Code separation unit 53 which is code separation means, CPU 54 which is reception control means, and ROM which is reception cycle storage means.
55 and a DIP switch 56 which is a reception identification code confirmation means.

The ROM 55 and the DIP switch 56 in this embodiment have the same configurations as the ROM 44 and the DIP switch 42 in the transmission section, and a predetermined code is set in the DIP switch 56 by the user. It outputs the indicated signal. Also, ROM
55 stores a transmission cycle corresponding to each code that can be set in the DIP switch 56.

The oscillator 5 having an oscillation frequency equal to that of the oscillator 47
The transmission signal received via 1 is converted into a digital signal after being amplified by an amplifier 52 including an A / D converter (not shown). The code separating unit 53 is the amplifier 5
Two outputs are input, the identification code 2 and the measurement data 3 are separated and sent to the CPU 54. The CPU 54 confirms whether the identification code 2 matches the code indicated by the output of the DIP switch 56, and if the identification code 2 matches, the measured data is received as valid, and it corresponds to the code indicated by the output of the DIP switch 56. Reception is performed according to the transmission cycle stored in the ROM 55. If the identification code 2 does not match the code indicated by the output of the DIP switch 56, the measurement data 3 is discarded as invalid data.

In the present embodiment configured as described above, even if the transmission is performed by a single frequency, it is possible to transmit only the type of code set by the DIP switch. For example, if the DIP switch is 4 bits, 16 types of data can be transmitted even with a single frequency.

Further, since the transmission cycle differs depending on the type of code set by the DIP switch, when an FM wave is used as a transmission frequency, a weak level signal is canceled by a strong level signal. Even if a state occurs, if the codes set by the DIP switches are different, the transmission cycle gradually shifts after a lapse of a predetermined time, so that each interference state does not continue. Further, the work required to prevent the occurrence of interference only needs to be changed when the codes set in the dip switches match, thus improving workability.

Further, in order to maintain the transmission quality of the measurement data, the identification code added to the measurement data may be transmitted at a transmission frequency different from the transmission frequency of the measurement data. The transmission frequency of the identification code is -3d of the electric field level of the transmission frequency of the measurement data.
A transmission frequency of about B is used, and the transmission circuit 4
6 and the CPU 53 may be provided with this kind of function. For example, the oscillator has a standard oscillation frequency of 34K.
Hz, and the frequency of about -3 dB is 34.3 KH.
When using z and those at 33.7 KHz,
By assigning the frequency data at 34.3 KHz and the frequency data at 33.7 KHz to "0" and "1", respectively, the measurement data and the identification code can be reliably separated and recognized, so that the transmission quality is maintained. You can
Also, as for the identification code, since the frequency up to about −3 dB is used as described above, the transmission capacity does not decrease.

In the above embodiment, the identification code is set by the DIP switch. However, the identification code may be directly written in the RAM or the like, and the identification code setting means is particularly preferable. It is not limited.

[0025]

Since the present invention is configured as described above, it has the following effects.

In the method according to the first aspect and the method according to the second aspect, even if the same frequency signals are used, interference does not occur as long as different identification codes are given. Therefore, the change of the transmission frequency required to prevent the occurrence of mutual interference is the same transmission frequency, and
Since the identification codes are also limited to when they are the same, it is possible to reduce the necessary number of times of performing the work itself and improve workability.

Further, since the transmission cycle is changed according to the identification code, even if an interference state occurs in which a weak level signal is canceled by a strong level signal, this interference state is resolved. Thus, there is an effect that it is possible to prevent the interference state from continuing. According to the third aspect, in addition to the above effects, there is an effect that the quality of transmission data can be kept constant.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention, in which (a) is a transmitting unit for inputting data measured by a measuring device and outputting as a wireless transmission signal, and (b) is a receiving unit configuration. Is shown.

FIG. 2 is a diagram showing a transmission signal used in the embodiment shown in FIG.

FIG. 3 is a diagram for explaining a conventional underwater radio signal transmission system, in which (a) shows a configuration,
(B) shows a transmission cycle.

[Explanation of symbols]

 1 Periodic Signal 2 Identification Code 3 Measurement Data 41 A / D Converter 42 DIP Switch 43 Code Setting Section 44 ROM 45 CPU 46 Transmission Circuit 47 Transducer 51 Transducer 52 Amplifier 53 Code Separation Section 54 CPU 55 ROM 56 DIP Switch

Claims (3)

[Claims] 1. The transmission side assigns an identification code to a radio signal and sends the radio signal at a predetermined transmission cycle according to the identification code, and the reception side confirms the identification code to address itself. The wireless signal transmission method underwater is characterized by confirming whether or not, and discarding anything other than those addressed to itself. 2. An underwater wireless signal transmission method for transmitting underwater by a wireless signal, wherein the transmitting side converts the transmission data into a digital signal.
A D converter, an identification code assigning unit for assigning a predetermined identification code to the digital signal converted by the A / D converter, a different transmission cycle for each identification code, and the assigning unit by the identification code assigning unit. And a digital signal to which the identification code is added by the identification code assigning means, at a transmission cycle indicated by the output of the transmission cycle storing means. A transmission control unit for converting the output of the transmission control unit into a wireless transmission signal and outputting the wireless transmission signal, and a receiving unit for converting the wireless transmission signal into a digital signal on the receiving side; Code separation means for separating the identification code and the transmission data from the converted digital signal, and a signal indicating the identification code to be received. Reception identification code confirmation means for outputting, reception cycle storage means for storing a reception cycle different for each identification code to be received, identification code of the code separation means output should be received indicated by the reception identification code confirmation means output It is confirmed whether or not it matches the identification code. If they match, the receiving operation is performed in the receiving cycle stored in the receiving cycle storing means corresponding to the identifying code. If they do not match, the receiving operation is performed. A radio signal transmission method in water, which is provided with a reception control means that does not perform the operation. 3. The underwater wireless signal transmission system according to claim 2, wherein the transmitting means transmits the transmission data and the identification code as a wireless transmission signal of a different frequency. .