JPS643081Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an additional device that is added to a radio telephone device that communicates using frequency modulated radio waves to provide the function of detecting the arrival direction of received radio waves. It is something.

[Conventional technology]

On ships, in addition to radio telephone equipment for safe navigation,
Devices for position and direction finding, such as radio direction-finding devices, are indispensable; however, due to financial resources, small vessels are generally equipped with radiotelephone devices first, and other devices are installed later. sequentially,
I'm trying to keep replenishing my equipment.

[Problem that the invention attempts to solve]

Even in the above cases, it is necessary to install equipment for position and direction detection as soon as possible from the point of view of navigational safety, and considering the above-mentioned financial situation, it is desirable to find a method that can be done as cheaply as possible. .

Therefore, it would be extremely convenient for users if there were a device that could achieve the purpose at a low cost, such as by using an existing device.

[Means for solving problems]

This device combines the receiving function of the radio telephone device described above and adds a direction finding function.This additional device can be used to (a) switch between a direction finding antenna and the induced voltage of this antenna; an antenna section for direction finding, which has an antenna switching device for switching and extracting information signals including information on the direction of arrival of radio waves; a mode switch for providing one of the direction information signals as a reception input of the wireless telephone device; a switching wave generator for generating the above-mentioned switching wave; a low frequency demodulator for obtaining a direction signal using the switching wave and a low frequency signal demodulated into information of the switching frequency obtained on the audio output side when an information signal is applied; The above-mentioned problems can be solved by a means formed by two parts: a direction indicator for obtaining a direction indication, and a direction indicator having a direction indicator.

〔Example〕

Examples will be described below with reference to the drawings.

In the figure, a radio telephone device 1001 is a general marine radio telephone device, and is mainly composed of a transmitting section 14 and a receiving section 4.

The reception function section is configured to convert the transmitted voice from the microphone 15 into a transmission signal in the transmission section 14, and transmit it as a radio wave from the antenna 1.
The received signal obtained by receiving the wave is applied to the high frequency input 501 of the receiving section 4, amplified by the high frequency amplifier 5, frequency detected by the detector 6, and outputted by the audio amplifier 7 to the audio output 7.
01 to drive the speaker 8.

The additional device of the present invention combines the components from the high frequency input 501 to the audio output 701 of the radio telephone device 1001 having such a configuration as part of the direction finding function, and adds an antenna section for direction finding.
002 and the direction indicating section 2 are connected as an additional device 1000, it can be used as a wireless direction finding device.

The direction finding antenna 13 is one half of the wavelength of radio waves.
Element 13 of four dipoles with a length close to
The antenna switching signal 1 applied to the antenna switching device 12 has a structure in which antennas 01 to 1304 are orthogonally arranged.
201, elements 1301 to 13
04, the voltage induced by the radio wave is sequentially switched and extracted to create an information signal 1202 containing information about the arrival direction of the radio wave.

The direction indicating section 2 includes a mode switch 3, a low frequency demodulator 9, and a switching wave generator 10, and applies a switching wave to the antenna switch 12 and the low frequency demodulator 9.

The bandwidth of the high frequency amplifier 5, the detector 6, and the audio amplifier 7 of the receiving section 4 is suitable for voice communication.
If the frequency is assumed to be 3KHz, the appropriate frequency of the switching wave is around 2KHz. This switching wave, that is,
It is better to use a higher frequency for the switching signal 1201 in order to speed up direction finding processing, but if the frequency is set to a frequency that spans the full bandwidth, the disturbance in the phase delay at both ends will cause the group delay to become unbalanced. It is preferable to select a frequency of this level because the signals that become the detection direction components will not pass accurately all at once, leading to direction detection errors. By sequentially switching the antenna elements 1301 to 1304 using this switching wave, the frequency of the received radio waves can be changed.
In the case of the 150 MHz band, frequency modulation equivalent to several kilohertz occurs, and the state of the modulation changes depending on the direction in which the radio waves arrive. Regarding the occurrence of frequency modulation with a detection direction component, see, for example, the issue of [Radio Direction Measuring Instrument] published by Corona Publishing, August 1955.
pp. 130-133 (hereinafter referred to as literature), JP-A-1972-
96882, etc., and has been well known for a long time, so it will be omitted here. In this way, the information signal 1202 is modulated by the antenna switching signal 1201 and has a modulation state according to the arrival direction of the radio wave.
is passed through the mode switch 3, and the high frequency output 301,
A high frequency input 501 is amplified by a high frequency amplifier 5, frequency detection is performed by a detector 6, the change is converted into an amplitude change, amplified by an audio amplifier 7, and an audio output 7
01 to drive the speaker 8 and obtain a low frequency input 901.

If the received radio waves have been modulated by a phone call, the audio output from the phone call will be mixed into the audio output 701, but the information signal 1202 will be demodulated into information on the frequency of the switching wave. A low frequency input 901 is applied to the low frequency demodulator 9.

The low frequency demodulator 9 compares the switching wave generated by the switching wave generator 10 with the low frequency input 901 demodulated into frequency information of the switching wave as described above, performs detection,
Amplify the direction signal 902 and send it to the direction indicator 11
supply to.

This part of the low frequency demodulator 9 is a well-known part as shown in the indicator circuit in Figure 108 on page 143 of the above-mentioned document, of which the part corresponding to the low frequency demodulator 9 is used. To summarize, for example,
As shown in Figure 2, the BPF circuit 91 is a bandpass filter and the low frequency input 9
Only the detection direction component in 01 is extracted.

The phase shift circuit 92 receives the information signal 1202 from the receiving section 4.
Since the switching phase caused by the switching wave in the output that has undergone this delay is delayed until it is output as the low frequency input 901 through the switching wave generator 10, the switching wave is applied from the switching wave generator 10 to the synchronous detection circuit 93 (described later). The switching synchronization point of the low frequency input 901 is delayed until the next switching synchronization point of the switching wave in order to match the switching phase of the switching wave.

The synchronous detection circuit 93 switches the output signal of the phase shift circuit 92 using a switching wave (a signal corresponding to the switching signal 1201) provided from the switching wave generator 10, and
It outputs signals separately for each pole to be applied to each pole (for example, N, S, E, and W) of the orthogonal magnetic field of the direction indicator 11, which will be described later. These signals for each pole are amplified to a desired output by an amplifier circuit 95, and the signals are input to the direction indicator 11 as a direction signal 902, so that a direction direction can be obtained as described later.

Therefore, for the purpose of improving the accuracy of this direction indication, for example, BPF9 is used as is well known.
It is effective to purify the information signal by inserting an audio filter from the low frequency input 901 to reduce the contamination of voice due to telephone calls by making the input signal 901 narrowband.

The direction indicator 11 is, for example, a positionless ammeter with four poles for creating orthogonal magnetic fields, and has a structure corresponding to the number of elements of the direction finding antenna 13 and the antenna switching signal 1201. Therefore, the direction signal 902 obtained by demodulating the information signal 1202 when the element 1301 is installed in the north direction is used to control the pointer 110 of the direction indicator 11.
The operation of the low frequency demodulator 9 may be set so that 2 indicates the north direction 1101.

The transmitting section 14 and the microphone 15 are shown in the case of a wireless telephone device in combination with the receiving section 4.

In this case, a transmitter/receiver switch 16 is provided, and when the transmitter 14 transmits radio waves, the high frequency input 50
It is desirable to switch the mode switch 3 to the received signal 101 at the same time as turning off the signal 101.

[Effect of idea]

According to this invention, as described above, most of the receiving section 4 of the existing wireless telephone device 1001 can be used to add a wireless detection function, so compared to the case where an independent wireless direction finding device is separately installed, It is much cheaper and the entire device can be made smaller, so it has the advantage of being easily installed in the narrow cabin of a small ship.

[Brief explanation of the drawing]

FIG. 1 shows the configuration of the present invention and a wireless telephone device, and FIG. 2 shows an example of the configuration of the low frequency demodulator 9 in FIG. 1...Receiving antenna, 101...Receiving signal, 2
...Direction indicator, 3...Mode switch, 301
...High frequency output, 4...Receiving section, 5...High frequency amplifier, 501...High frequency input, 6...Detector, 7
... Audio amplifier, 701 ... Audio output, 8 ... Speaker, 9 ... Low frequency demodulator, 901 ... Low frequency input, 902 ... Direction signal, 10 ... Switching wave generator, 11 ... Direction indication Vessel, 1101...north direction,
1102... Pointer, 12... Antenna switch, 1
201... Antenna switching signal, 1202... Information signal, 13... Direction finding antenna, 1301...
Element, 1302...Element, 1303
...Element, 1304 ...Element, 14
...Transmitter, 15...Microphone, 16...
Transmit/receive switch.

Claims (1)

[Claims for Utility Model Registration] An additional device for providing the function of detecting the arrival direction of received radio waves by serving as the receiving section of a radio telephone device that communicates using frequency modulated radio waves, from the reception input to the audio output. a direction-finding antenna section having a direction-finding antenna and an antenna switching device for switching and extracting the induced voltage of the direction-finding antenna using a switching wave to obtain an information signal including information on the direction of arrival; b a mode switch for applying either the received signal obtained by the communication antenna or the information signal to the receiving input; a switching wave generator for generating the switching wave; and a switching wave generator for generating the switching wave; a low frequency demodulator for obtaining a direction signal using the switching wave and a low frequency signal demodulated into frequency information of the switching wave obtained on the audio output side when the information signal is applied to the input side; An additional device for direction finding, characterized in that it is formed of two parts: a direction indicator for obtaining an indication of the direction of arrival based on the direction signal; and a direction indicator having a direction indicator.