JPH09261178A - Hybrid receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow the receiver installed in a mobile object to surely receive a transmission signal even when a transmitter adopts the millimeter wave communication system or the optical space communication system. SOLUTION: In the case of receiving an optical signal sent from a transmitter adopting the optical space communication system, an optical signal reception section 10 consisting of a condenser lens 11, a light receiving element 12, a pre amplifier 13, a band limit filter 14, a limiter and demodulator 15 receives the signal and the received signal is given to a signal automatic selection circuit 31. Furthermore, in the case of receiving an optical signal sent from a transmitter adopting the millimeter wave communication system, the signal is received by a millimeter signal reception section 20 consisting of a millimeter wave reception antenna 21, a down-converter 22, an intermediate frequency amplifier 23, a band limit filter 24 and a demodulator 25 receives the signal and the resulting signal is given to the signal automatic selection circuit 31. The signal automatic selection circuit 31 detects the presence of an output signal from the optical signal reception section 10 and the millimeter wave signal reception section 20, selects either reception section from which the output signal is detected and provides an output of the output signal to an external output terminal 33 via a video amplifier section 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid receiver capable of receiving a signal on the mobile side regardless of whether the millimeter wave communication system or the optical space communication system is used as the transmitter installed on the fixed body side. Regarding

[0002]

2. Description of the Related Art Conventionally, in transportation facilities such as railways, in order to improve safety, for example, a monitor is installed near a driver's seat of a train, and a transmitter installed at a predetermined interval along a track, for example, in front of the train. Information such as the status and the level crossing status is transmitted to the train-side receiving device and displayed on the monitor in the driver's seat. In this case, information is generally transmitted using the millimeter wave communication method on the ground, but communication becomes impossible when the train enters the tunnel. Therefore, the optical signal is transmitted to the train by the optical space communication transmitter in the tunnel. I am trying to send it to the side.

In the communication system using the millimeter wave communication or the optical space communication, the millimeter wave communication requires a millimeter wave transmitter / receiver and the optical space communication needs an optical space transmitter / receiver. That is, it is necessary to install both the millimeter wave signal receiver and the optical signal receiver on the train side.

[0004]

Conventionally, in consideration of the communication environment as described above, consideration has been given to a mixture of transmitters in which a millimeter wave transmission type or optical space communication type transmitter is installed depending on the installation environment. In this case, both the millimeter wave signal receiver and the optical signal receiver must be installed on the mobile side, and which receiver on the mobile side depends on whether the transmitter is for the millimeter wave signal or the optical signal. There is a problem that communication cannot be performed unless the use of is switched manually.

The present invention has been made in order to solve the above-mentioned problems, and the optical / millimeter wave circuit is manually operated regardless of whether the transmitter is a millimeter wave communication transmitter or an optical space communication light transmitter. An object of the present invention is to provide a hybrid receiver that can reliably receive a signal without switching by operation.

[0006]

A hybrid receiver according to the present invention comprises a millimeter wave signal receiving section for receiving a millimeter wave signal transmitted from a transmitter by the millimeter wave communication system, and a transmitter by the optical space communication system. An optical signal receiving unit that receives an optical signal to be transmitted, and an automatic selection circuit that detects the presence / absence of output signals from the millimeter wave signal receiving unit and the optical signal receiving unit and selects the receiving unit that outputs the signal. And the millimeter-wave signal receiving unit and the optical signal receiving unit are integrally configured.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an external view of a hybrid receiver 1 according to an embodiment of the present invention, and FIG. 2 is a block diagram showing an internal configuration.

In FIG. 1, reference numeral 2 denotes a case main body of the hybrid receiver 1 whose front opening is divided into left and right parts, one side of which is provided with an optical signal incident section 3 and the other side of which is provided with a millimeter wave signal incident section 4. The case main body 1 is integrally provided with a millimeter wave signal receiving portion and an optical signal light receiving portion, and is configured as shown in FIG.

In FIG. 2, reference numeral 10 denotes an optical signal receiving section, which comprises a condenser lens 11, a light receiving element 12, a preamplifier 13, a band limiting filter 14, and a limiter / demodulator 15. Reference numeral 20 denotes a millimeter wave signal receiving unit, which is a millimeter wave receiving antenna 2
1, a down converter 22, an intermediate frequency amplifier 23, a band limiting filter 24, and a demodulator 25. Then, the signal demodulated by the limiter / demodulator 15 of the optical signal receiving section 10 and the signal demodulated by the demodulator 25 of the millimeter wave signal receiving section 20 are input to the optical signal / millimeter wave signal automatic selection circuit 31. To be done. The optical signal / millimeter wave signal automatic selection circuit 31 detects the presence / absence of output signals from the limiter / demodulator 15 and the demodulator 25, and based on the detected signals, the demodulator 1
One of the signals 5 and 25 is automatically selected by, for example, a diode switch, the selected demodulated signal is amplified by the common video amplifier 32 for the optical signal / millimeter wave signal, and then output to the outside from the external output terminal 33. .

In the hybrid receiver configured as described above, whether a signal is sent from a fixed transmitter by an optical space communication system or a millimeter wave communication system,
The transmitted signal can be automatically selected and received.

For example, if an optical signal is sent from a transmitter of the optical space communication system, this optical signal is condensed by the condenser lens 11 and input to the light receiving element 12, and converted into an electric signal. The electric signal converted by the light receiving element 12 is amplified by a preamplifier 13, and then a signal in a predetermined band is taken out through a band limiting filter 14 and input to a limiter / demodulator 15. This limiter / demodulator 15
Input the input signal to the optical signal / millimeter wave signal automatic selection circuit 31 by limiting the input signal with a constant amplitude and demodulating. The optical signal / millimeter wave signal automatic selection circuit 31 detects the output signal of the limiter / demodulator 15 in the absence of the signal from the demodulator 25 and selects the signal from the limiter / demodulator 15 to amplify the video. Output to the unit 32. This video amplifier 32
Amplifies the signal from the limiter / demodulator 15 selected by the optical signal / millimeter wave signal automatic selection circuit 31 and outputs the amplified signal to the outside from the external output terminal 33.

Further, when a millimeter wave signal is sent in place of the above optical signal from a transmitter using the millimeter wave communication system,
The millimeter wave signal is received by the millimeter wave receiving antenna 21 and converted into an intermediate frequency signal by the down converter 22. This intermediate frequency signal is amplified by the intermediate frequency amplifier 23, and then is demodulated by the demodulator 25 through the band limiting filter 24.
Sent to The demodulator 25 includes a band limiting filter 24.
The signal of the predetermined band output from the signal is demodulated and output to the optical signal / millimeter wave signal automatic selection circuit 31. The optical signal / millimeter wave signal automatic selection circuit 31 detects the output signal of the demodulator 25 in the absence of the signal from the limiter / demodulator 15, and selects the output signal of the demodulator 25 to select the video amplification unit. It is output to the outside through the 32 and the external output terminal 33.

As described above, the hybrid receiver 1 is
Regardless of whether the signal is sent from the transmitter by the optical space communication method or the millimeter wave communication method, the signal sent is selected and output to the outside.

Next, a specific example of use will be described with reference to FIG. FIG. 3 shows an example in which the hybrid receiver 1 is mounted on a train 42 that passes through a tunnel (or an underground tunnel) 40 and a ground 41. The hybrid receiver 1 is installed at the forefront of the train 42. Then, a light transmitter 43 is provided near the exit in the tunnel 40.
Is installed to transmit an optical signal toward the forefront of the train 42 traveling in the tunnel 40, and a millimeter wave transmitter 44 is installed on the ground 41 to provide a millimeter wave signal to the train 42 running on the ground. I am trying to send you.

When the train 42 enters the tunnel 40, the signal transmitted from the millimeter wave transmitter 44 is cut off, and instead the optical signal from the light transmitter 43 is transmitted to the train 42.
In the hybrid receiver 1 mounted on the train 42, the optical signal from the light transmitter 43 is received by the optical signal receiver 10, demodulated, and input to the optical signal / millimeter wave signal automatic selection circuit 31.
When the demodulated signal output from the optical signal receiving unit 10 is input, the optical signal / millimeter wave signal automatic selection circuit 31 selects the signal from the limiter / demodulator 15 of the optical signal receiving unit 10 to perform video amplification. It is output to the outside, for example, a monitor in the driver's seat via the unit 32 and the external output terminal 33. The driver can confirm the content of the information sent from the light transmitter 43 by the display on this monitor.

When the train 42 exits from the tunnel 40 to the ground 41, the hybrid receiver 1 sends the light transmitter 43.
The millimeter-wave signal receiving section 20 receives the millimeter-wave signal sent from the millimeter-wave transmitter 44 instead of the optical signal from the. The millimeter wave signal received by the millimeter wave signal receiving section 20 is demodulated by the demodulator 25 and input to the optical signal / millimeter wave signal automatic selection circuit 31. When the demodulated signal is input from the millimeter wave signal reception unit 20, the optical signal / millimeter wave signal automatic selection circuit 31 receives the demodulator 25 of the millimeter wave signal reception unit 20.
The signal from is selected and is output to a driver's seat monitor or the like via the video amplifier 32 and the external output terminal 33.

As described above, the communication system suitable for the communication environment is used inside the tunnel 40 or on the ground 41, but the hybrid receiver 1 mounted on the train 42 is
When the transmission signal is received, the reception signal is automatically selected and output to a monitor or the like, so that the driver may enter the train 42 into the tunnel 40 or from the tunnel 40 to the ground 4
Even in the case of 1, the receiving circuit does not need to be manually switched and the driver can concentrate on the driving operation.

[0018]

As described above in detail, according to the present invention, the optical signal receiving unit and the millimeter wave can be used regardless of whether the transmitter uses the millimeter wave communication system or the optical space communication system. The transmission signal can be reliably received without switching the signal receiving unit by manual operation.

[Brief description of drawings]

FIG. 1 is a perspective view showing an external configuration of a hybrid receiver according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an internal circuit configuration in the same embodiment.

FIG. 3 is a flowchart showing a usage example in the same embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hybrid receiver 2 Case body 3 Optical signal incident part 4 Millimeter wave signal incident part 10 Optical signal receiver 11 Condenser lens 12 Light receiving element 13 Preamplifier 14 Band limiting filter 15 Limiter / demodulator 20 Millimeter wave signal receiver 21 Millimeter wave Reception antenna 22 Down converter 23 Intermediate frequency amplifier 24 Band limiting filter 25 Demodulator 31 Optical signal / millimeter wave signal automatic selection circuit 32 Video amplification unit 33 External output terminal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naohiko Senda 1406 Hasunuma, Omiya City, Saitama Yagi Antenna Co., Ltd. Omiya Factory

Claims (1)

[Claims] 1. A millimeter-wave signal receiving unit that receives a millimeter-wave signal transmitted from a transmitting device using the millimeter-wave communication system, and an optical signal receiving unit that receives an optical signal transmitted from the transmitting device using the optical space communication system. An automatic selection circuit for detecting the presence or absence of the output signal of the millimeter wave signal receiving unit and the optical signal receiving unit and selecting the receiving unit on the side outputting the signal. A hybrid receiver having a signal receiving unit integrally configured.