JPH10211366A - Radio control device of model - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio control device (PROPO), which can prevent, beforehand, radio wave jamming to other models currently using the same frequency band. SOLUTION: A radio control device 10 has a built-in receiving circuit 20 for receiving the same frequency band as a transmitting frequency band f0 from the transmitting device 11, and a built-in receiving intensity discrimination circuit 30. First, the receiving circuit 20 is operated by turning a power switch 2 on, and the receiving strength discrimination circuit 30 detects the presence of radio wave having same frequency band as the transmitting frequency band f0 of the radio control device 10. When the receiving intensity S is equal to a specified threshold SC or more, the transmission is not started, and when the receiving strength S is less than the specified threshold SC, the transmission is started.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio control device for a radio control model such as a model airplane, a model helicopter, and a model car (commonly referred to as a radio), and particularly to a situation in which a plurality of radio control models are in close proximity. TECHNICAL FIELD The present invention relates to a technology for preventing the problem of interference at the time of maneuvering.

[0002]

2. Description of the Related Art A radio control device of a so-called radio control model (hereinafter, also referred to as a "propo") such as a model aircraft or a model helicopter by radio control is currently assigned a transmission frequency of 27 MHz band, 40 MHz band and 72 MHz band. .

The modulation method used to be the AM method in the past, but the FM pulse modulation method (PPM method) is now mainstream.
Recently, the PCM method, which is regarded as having high reliability, has also been adopted.

The 27 MHz band has 13 bands and 40 M
In the Hz band, 13 bands are set, and in the 72 MHz band, 10 bands are set at intervals of 20 KHz.

[0005] The "band" means the number of transmission frequencies allocated within the frequency band. In other words, it indicates how many models can be operated without interference in the frequency band at the same time.

[0006] When enjoying the above radio control model, there are many cases where several to dozens of people operate their models at the same time on a propo at the same place (large and small competitions and contests are frequently held between enthusiasts). ing.).

In such a case, if the operation of the radio control model is started in the same frequency band in the same frequency band as that of the person who has already operated the radio control model, mutual interference occurs and the radio control model of the other party as well as the radio control model of the other party is operated. As a result, the radio-controlled model can no longer be controlled, and the model airplane or the like is immediately crashed and damaged.

At present, in order to avoid this interference trouble, enthusiasts visually check whether or not a person of the same frequency band is currently using the color of the ribbon attached to the tip of the transmitter's transmitting antenna. doing.

Further, a simple receiving device (referred to as a band monitor) dedicated to a radio control model for checking whether or not the same frequency band as that of the self is currently used at a local point is commercially available.

[0010]

However, even when the above-mentioned band monitor dedicated to the radio control model is used, firstly, it takes a few seconds after confirming that there is no radio wave emission by another transmitter. However, when radio waves of the same frequency band are transmitted from another radio during this time gap, the band check becomes meaningless.

Second, it is quite troublesome to carry a band monitor together with the radio and each time a band monitor is used, and the check tends to be neglected. Is less.

In addition, the existing radio system is configured to transmit radio waves as soon as the power switch is turned on. However, even when the radio control model is not operated, the condition of the engine and motor can be controlled.
When checking the condition of each servo, checking the condition of the transmitter, etc., the transmitter may be accidentally turned on for a short period of time and transmission may occur, which may adversely affect other radio control operations. Cannot be ignored.

[0013] As described above, the interference of the transmitted radio waves between a plurality of radios is not perfect by using a band monitor, and it is extremely incomplete to simply discriminate by the color of the ribbon. Expecting solely to the manners of enthusiasts must be extremely pessimistic.

On the other hand, there is a serious problem when the radio control model is operated near the same frequency band in the vicinity. Not only model airplanes, but also model cars and model ships run at high speeds, which can lead to personal injury as well as damage due to the inability to control the radio control model.

The present invention has been made in view of the above-described problem of radio control operation of a radio control model, and aims to improve the safety of radio control model control by preventing interference of the same frequency between a plurality of conventional radio transmitters.

[0016]

In order to solve the above-mentioned problems, the present invention provides: (1) a model radio control device, a receiving circuit for receiving the same frequency band as the transmission frequency band of the radio control device, and a reception intensity; In addition to the built-in discrimination circuit, when the power switch is turned on, the reception circuit first operates to detect the presence / absence of radio waves in the same frequency band as the transmission frequency band of the radio control device, and the reception strength discrimination circuit detects the reception strength. The present invention provides a model radio control device characterized in that transmission is not started when the value is equal to or more than a threshold value, and transmission is started when the value is less than a predetermined threshold value.

(2) In a model radio control device having a display unit, a receiving circuit for receiving a frequency band of the radio control and a receiving intensity discriminating circuit are built in, and the receiving circuit operates first when a power switch is turned on. The tuning circuit of the receiving circuit automatically searches for the frequency band of the radio control, and the frequency band detected by the receiving strength discriminating circuit at the receiving strength equal to or higher than a predetermined value is displayed on the display unit, and the transmission frequency of the radio control device is displayed. A radio control apparatus for a model, characterized in that transmission is started only when a band is detected with a signal strength equal to or higher than a predetermined value, but only when the band is lower than the predetermined value.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention according to claim 1 will be described with reference to a block diagram of a model radio control device shown in FIG.

In FIG. 1, a radio control device 1
0 includes a receiving circuit 20 for receiving the same frequency band as the transmitting frequency band f0 of the transmitting apparatus 11 and a receiving strength discriminating circuit 30, and when the power switch 2 is turned on, the receiving circuit 20 first operates and the receiving circuit 20 operates. The presence / absence of a radio wave in the same frequency band as the transmission frequency band f0 of the radio control device 10 is detected by the reception intensity determination circuit 30. If the reception intensity S is equal to or higher than a predetermined threshold value SC, the signal is not transmitted and a predetermined threshold is set. The circuit configuration is such that transmission is started when the value is less than the value SC.

The transmitting device 11 is the same as the conventional transmitting device and will not be described again. The receiving circuit 20 and the receiving strength discriminating circuit 30 which are characteristic components of the present invention are omitted.
The configuration will be mainly described below.

When the power switch 2 is turned on, the power circuit 4
Switch 8 inserted between the circuit and the receiving circuit 20
(The illustrated thyristor or transistor) is turned on, and the receiving circuit 20 and the receiving strength determining circuit 30 are turned on.
Is operated when the power is supplied thereto, but the electrical switch 5 inserted between the transmission device 11 and the power supply path is in the initial state of the OFF state and is ON unless the detection signal K described later becomes “high”. No power is supplied to the transmission device 11. As a result, the transmission device 11 does not operate immediately when the power switch 2 is turned on, and transmission is not started.

In the initial state when the power switch 2 is turned on, the antenna 6 is connected to the receiving circuit 20 by the switch 7.

The receiving circuit 20 transmits the received radio wave received from the antenna 6 to the intermediate frequency of 455 kHz through a front end section 24 including a high frequency amplifier (preamplifier) 21, a mixer 22, and a local oscillation 23, similarly to a general FM broadcast receiver. Frequency, the intermediate frequency amplifier 25, the limiter 2
6. A carrier signal in the same frequency band as the transmission frequency f0 of the radio is obtained by an intermediate frequency unit 28 (FM detection is not particularly required) including a filter 27 having a bandwidth of ± 5 kHz.

The magnitude of the received signal strength S of the carrier signal is determined by comparing it with a threshold value SC appropriately set by the received signal strength determination circuit 30. Receiving strength determination circuit 3
0 itself is realized by a differential amplifier circuit or a latch circuit or the like.

If there is no carrier signal or the signal strength S <SC (if it is considered that the frequency band f0 is not used), the detection signal K, which is the output of the reception strength discriminating circuit 30, is low. The signal becomes “high”, the electric switch 5 is turned on, power is supplied to the transmission device 11 and transmission is started, and the antenna 6 is switched to the switching device 7.
To switch to the sending side.

Then, the electric switch 8 is turned off and the receiving circuit 20 stops operating, but the electric switch 5 maintains the on state and the transmitting device 11 maintains the transmitting state.

On the other hand, when the signal intensity S ≧ SC of the carrier signal (when the frequency band f0 is used)
Means that the detection signal K of the reception strength discrimination circuit 30 remains "low" and the electrical switch 5 is still off,
Only the receiving circuit 20 maintains the ON state.

If the transmission is stopped even when the power switch is turned on as described above, means for preventing the transmitter from being erroneously recognized as a failure of the transmitter and a means for notifying that the transmission is stopped (the band is being used). It may be desirable to provide, for example, notification by sound (buzzer) or lamp display.

The control of each circuit described above may be performed by the CPU 31 of the microcomputer for controlling the transmitter, or may be realized by a simple logic circuit. In addition to controlling whether or not transmission is performed by supplying power to the transmission device 11 as described above, it is easily realized by inserting a control signal into an appropriate portion of a transmission circuit. It is clear that we can do that.

With the above-described configuration, the radio control apparatus 10 automatically avoids the trouble of radio interference with the radio control model of another radio control model operating nearby by using the same frequency band f0 as the radio control apparatus 10 itself, and erroneously transmits the radio control model. Fear can also be prevented.

Next, an embodiment according to a second aspect of the present invention will be described.

When the same frequency band as that of the radio control apparatus 10 is being used by the radio control apparatus 10, information on which of the other frequency bands is vacant is required.

If it is assumed that a plurality of transmitters are possessed or that the transmission frequency of the transmitter can be changed quickly, an appropriate vacancy is immediately obtained if the used band information (or vacant band information) is obtained. That is, you can move to the band and steer. In addition, current band information will be useful to enthusiasts.

An embodiment for displaying the band information will be described with reference to a block circuit diagram of a radio control device 40 of a model shown in FIG. Circuits having the same contents as those in FIG. 1 are denoted by the same reference numerals.

The radio control device 40 has a transmitting device 11 and a display unit 41 (generally, a liquid crystal display or an LED display).
Receiving circuit 50 for receiving 7 MHz band, 40 MHz band, or all or part of 72 MHz band) and receiving intensity discriminating circuit 30
When the power switch 2 of the power circuit 4 is turned on, the receiving circuit 50 first operates to automatically adjust the frequency band of the radio control to the tuning circuit of the receiving circuit 50 (the front end section 44 and the DTS section 45). ) Is searched and the frequency band detected by the reception strength discriminating circuit 30 with the reception strength S equal to or higher than the predetermined value SC is displayed on the display unit 41, and the reception frequency band f0 of the radio control device 50 is set to the reception value equal to or higher than the predetermined value SC. The transmission is not performed when the intensity S is detected, and is started only when the intensity is less than the predetermined value SC.

Here, a DTS (abbreviation for digital tuning system) section 45 of the receiving circuit 50 includes a frequency dividing synthesizer 46, a controller display driver 47 and a display section 41 (of the transmitting apparatus 11) used in a general FM broadcast receiving apparatus. Information display), and the local oscillation 4
3 is a VCO (Voltage Controlled Oscillator) and the frequency is locked by a PLL. By setting the reference frequency to 20 KHz, reception can be performed every 20 KHz.

The other configuration is the same as that of the above-described radio control device 10.

The determination standard (threshold value SC) of the presence / absence of a radio wave in the reception intensity determination circuit 30 is set based on a rational reference as to whether or not the reception intensity S is sufficient to perform radio control of the model. It is also important to detect a certain duration (a few milliseconds to a few tens of milliseconds). Simply, it is sufficient to judge whether the signal strength is zero or not, or to judge the signal strength in consideration of noise or error. Therefore, the receiving sensitivity is not required to be particularly high, and is about the same as the receiver mounted on the model.

Further, the receiving circuits 20, 5
0 does not need to discriminate the radio control signal (pulse signal in the case of the FM method), and it is sufficient to detect the presence or absence of the carrier, so that the difference of the modulation method does not matter. That is, various transmission systems (AM system, FM (PPM) system, PCM system)
Can be detected.

The display unit 41 displays the name of the currently used frequency band directly in characters (numeric characters) or individually writes the band name on the surface of the radio, and lights a lamp indicating the used band location. And the like. For example, FIG. 3 is a plan view showing the operation surface of the radio control device 40 of the model of the present invention. When the power switch 2 is turned on, the screen of the display unit 41 displays the band number (5
4, 85) are displayed as numbers, indicating that the own oscillation frequency band is in use at 54 and transmission is stopped.

As a reminder, once the transmitting device 11
Is activated to start the transmission of the radio, the receiving circuit 20,
50 does not operate, the reception strength discrimination circuit 30 does not operate, or the detection signal K is ignored. Further, once the transmission is started, the transmission is maintained even if interference occurs due to transmission by another transmitter thereafter.

The radio of the present invention is not limited to the configuration shown in the above embodiment. First, means for detecting whether or not the transmission frequency of the radio has already been used by receiving the radio signal. After that, the system includes a configuration in which a series of control operations of transmitting a message after confirming the non-use state after the investigation is performed.

With the spread of the radio of the present invention,
It goes without saying that the trouble of interference between the radios can be resolved and the safe operation of the radio control model can be enjoyed.

[0044]

As described above, the model radio control device (propo) according to the present invention detects whether a radio wave of the same frequency band as its own transmission frequency band is being transmitted before transmitting. Since the transmission is started for the first time when the signal is not transmitted from another radio, it has an excellent effect that it is possible to prevent radio wave interference to other radio control model operation in use.

Also, in the radio control device of the present invention, when the power switch is turned on, the band used by another radio in the radio control model allowable frequency band is displayed, so that the transmission frequency bands of its own radio overlap. In this case, there is an excellent effect that the used frequency band can be easily changed.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of an embodiment of a radio control apparatus for a model aircraft of the present invention.

FIG. 2 is a block circuit diagram of another embodiment of the radio control apparatus of the model aircraft of the present invention.

FIG. 3 is a plan view showing an operation surface of the radio control device of the model aircraft of the present invention.

[Explanation of symbols]

 2 Power switch 4 Power circuit 5, 8 Electrical switch 6 Antenna 7 Switching device 10, 40 Radio control device 11 Transmitting device 20, 50 Receiving circuit 21 High frequency amplifier (preamplifier) 22 Mixer 23, 43 Local oscillation 24 Front end unit 25 Intermediate Frequency amplifier 26 Limiter unit 27 Filter 28 Intermediate frequency unit 30 Reception intensity discriminating circuit 41 Display unit 44 Front end unit 45 DTS unit 46 Frequency division synthesizer 47 Controller display driver f0 Transmission frequency S Reception intensity SC threshold K detection signal

Claims (2)

[Claims] 1. A model radio control device includes a receiving circuit for receiving the same frequency band as a transmission frequency band of the radio control device and a reception intensity discriminating circuit, and the receiving circuit operates first when a power switch is turned on. The reception intensity discrimination circuit detects the presence or absence of radio waves in the same frequency band as the transmission frequency band of the radio control device.If the reception intensity is equal to or higher than a predetermined threshold, the signal is not transmitted. A radio control device of a model, characterized in that transmission is started at a time. 2. A radio control apparatus of a model having a display unit, wherein a receiving circuit for receiving a frequency band of radio control and a receiving strength discriminating circuit are built in. The tuning circuit of the receiving circuit automatically searches for the frequency band of the control, and the receiving strength discriminating circuit displays the frequency band detected at the receiving strength equal to or more than the predetermined value on the display unit, and the transmitting frequency band of the radio control device is set to the predetermined value. A radio control device for a model, characterized in that a signal is not transmitted when detected with a signal strength equal to or higher than a value, and transmission is started only when the signal intensity is lower than a predetermined value.