JPH11275435A - Wireless image transmission equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit the remote control of a camera or universal head at a monitoring place by transmitting a control command signal for controlling an image pickup device on the transmission side from the reception side during transmission stoppage period of a main signal from the transmission side to the reception side. SOLUTION: When a commander 6 on the reception side outputs a control command signal, the signal is inputted through an input terminal CTLIN to a transmitter TX2 , radiated from a transmission antenna ANT2-2 to the transmission side during transmission stoppage period of a main signal from the transmission side to the reception side, and inputted successively through a reception antenna ANT1-2 , a receiver RX1 and an output terminal CTLOUT on the transmission side to a controller 3. In response to this control command, the controller 3 performs the control, for example, of an image pickup device 1 such as the control of a camera or universal head. Besides, a control response signal outputted by the controller 3 is inputted to a transmitter TX1 , radiated from a transmission antenna ANT1-1 to the reception side during the transmission period of the main signal from the transmission side to the reception side and inputted to the commander 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image radio transmission apparatus for transmitting an image signal over a long distance from a transmitting side to a receiving side.

[0002]

2. Description of the Related Art For the purpose of monitoring offices and warehouses separated by roads and rivers, and monitoring dangerous places such as volcanic activity and landslide sites, as shown in FIG. Normal video camera or monitor camera 11
An imaging device 1 including a camera head 12 and a transmitting unit 2 are installed, and a receiving unit 4 and a monitor device 5 such as a monitor television are installed at a place (monitoring place) where monitoring is performed a few km away from a monitoring target place. An image wireless transmission device that transmits an image signal (which may include an audio signal) captured by the imaging device 1 from the transmission unit 2, receives the image signal by the reception unit 4, and displays the image on the monitor device 5 is known. Have been.

In this image radio transmission apparatus, a certain limit is imposed on the transmission output on the transmission side and the output of the antenna ANT ₁ (for example, the antenna power is limited to 10 mW / MHz or less). In order to efficiently receive the transmitted radio wave under the circumstances, the receiving side uses a high directivity, high gain receiving antenna as the receiving antenna ANT ₂ , and eliminates unnecessary signals by an input filter in the receiving side unit 4. An ultra-low noise amplifier is used for the amplifier. As a modulation method, a direct spread spectrum method which is strong against disturbance and noise and excellent in confidentiality and confidentiality is adopted, and a radio center frequency is, for example, about 2.4 GHz.
z, the spreading bandwidth is set within, for example, 22 MHz, the modulation speed is set, for example, at a maximum of 2 Mbps, and the transmission distance is set, for example, at about 2.5 km.

[0004]

However, according to the conventional image radio transmission apparatus, the direction and height of the camera
Alternatively, when it is desired to change the enlargement ratio or the like of the image captured by the camera 11, it is necessary to go to the monitoring target site and adjust the camera 11 and the camera platform 12.

[0005] The present invention focuses on the above problems,
It is an object of the present invention to provide an image wireless transmission device capable of remotely controlling a camera and a camera platform while staying at a monitoring place.

[0006]

SUMMARY OF THE INVENTION An image radio transmission apparatus according to the present invention is an image radio transmission apparatus for transmitting an image signal from a transmission side to a reception side over a long distance. And a control command signal for controlling the transmission-side imaging device is transmitted from the reception side to the transmission side during the transmission interruption period of the main signal from the transmission side to the reception side, and the imaging device is transmitted to the transmission side. Is controlled.

[0007]

FIG. 1 is a block diagram showing a configuration of an image radio transmission apparatus according to an embodiment of the present invention.

In FIG. 1, an image radio transmission apparatus is divided into a transmitting side and a receiving side which are separated from each other by a long distance, and the transmitting side includes an image pickup apparatus 1 comprising a camera platform and a television camera attached to the camera platform. And a transmitting unit 2 composed of a transmitter TX ₁ and a receiver RX ₁ , a transmitting antenna ANT _1-1 having a limited effective radiation (radiation) power, for example, a dipole antenna, and a control device 3 for controlling the imaging device 1 When high gain, is installed and a high directivity of the receiving antenna ANT _1-2 e.g. Yagi antenna, whereas, on the receiving side, high gain, and high directivity of the receiving antenna ANT _2-1 e.g. Yagi antenna receiver RX
₂ and a transmitter TX ₂ , a monitor unit 5 composed of a monitor television, a command device 6 for outputting a control command signal for controlling the imaging device 1, and an effective radiated power limited. A transmission antenna ANT _2-2, for example, a dipole antenna is provided.

An image signal output from the imaging device 1 on the transmission side (which means an image signal in a broad sense including a synchronizing signal, which is herein referred to as a main signal, and sometimes includes an audio signal) is input. emitted to the receiving side from the transmitting antenna ANT _1-1 via the terminal S _iN and the transmitter TX ₁ in order,
The image is displayed as an image on the monitor device 5 via the receiving antenna ANT _2-1 on the receiving side, the receiver RX _2, and the output terminal S _OUT in this order (may include sound).

When the command device 6 on the receiving side outputs a control command signal, the control command signal is input to the transmitter TX ₂ via the input terminal CTL _IN , and the main signal from the transmitting side to the receiving side is transmitted. During the transmission interruption period, the signal is radiated from the transmitting antenna ANT _2-2 toward the transmitting side, and is radiated toward the transmitting side.
_1-2 , the control signal is input to the control device 3 via the receiver RX ₁ and the output terminal CTL _OUT in order, and the control device 3 controls the imaging device 1 according to the control command signal, for example, controls the camera or the camera platform. .

The control device 3 to which the control command signal is input
Outputs a control response signal, the control response signal through the input terminal ANS _IN is input to the transmitter TX _1, the transmission period of the main signal to the receiving side from the transmitting side, the transmitting antenna A
The signal is radiated from the NT _1-1 toward the receiving side, and the receiving antenna ANT _2-1 , the receiver RX ₂ and the output terminal ANS _OU on the receiving side are radiated.
It is input to the command device 6 via _T in order. Command device 6
Confirms from the control response signal that the transmitting side has accepted the control command signal.

FIGS. 2 and 3 show a specific example of the configuration of the transmitting unit 2 and a specific example of the receiving unit 4 in an image radio transmission apparatus using analog modulation (AM, FM, PM), respectively. .

As shown in FIG. 2, the transmitting unit 2
Video amplifier V-AMP, radio frequency oscillator RF-OS
C, video modulation circuit V-MOD, control response signal memory A
NS-MEM, control response signal addition circuit ANS-ADD,
Central processing unit CPU ₁ , On-off controller
ON / OFF-CTL, radio frequency power amplifier RF-
PA, band pass filter BPF, ultra low noise amplifier LO
W-NOISE-AMP, Receiver RX₁ And main signal detection
A circuit CW-DET is provided. Where the radio frequency oscillator
RF-OSC, video modulation circuit V-MOD and on / off switch
Controller ON / OFF-CTL and radio frequency power
The configuration in which the transmitter TX-AMP is combined with the₁ 
It corresponds to.

As shown in FIG. 3, the receiving side unit 4
Bandpass filter BPF, ultra-low noise amplifier LOW-N
OISE-AMP, receiver RX ₂ , video amplifier VA
MP, control response signal separator ANS-SEP, main signal detection circuit CW-DET, central processing unit CPU
_2, includes a control command signal memory CTL-MEM, the on-off controller ON / OFF-CTL and transmitter TX _2.

Next, the operation of the transmitting unit 2 and the receiving unit 4 will be described with reference to the timing chart shown in FIG.

In the transmitting unit 2, central processing is performed.
Unit CPU₁ Indicates the horizontal level during the vertical blanking period.
Period signal (pulse width t₁ ) Is thinned out and the water is thinned out
Predetermined time t from the rise of the flat sync signal_Two (> T
₁ ) When the clock signal is turned on and off
Controller ON / OFF-CTL and output the communication mode.
From the previous transmission mode (reception disabled mode) to the transmitter T
X₁ Mode in which the image signal cannot be transmitted,
To ON / OFF controller ON / O
Ultra low noise amplifier LOW-NOISE by FF-CTL
Switch the AMP to the active state and activate the receiver RX₁ By
Switch to the mode in which the control command signal can be received, that is, the reception mode.
Replace. Duration of this reception mode (transmission disabled mode)
t_Three Is the time t from the period H of the horizontal synchronization signal._Two Subtract
Subtracted time Ht_Two Is set to a smaller value than
You. And a central processing unit CPU₁ Is the continuation
Interval t_ThreeON / OFF controller ON / O
Outputs the mode return command signal to FF-CTL, and sets the communication mode.
The mode is changed from the reception mode (transmission disabled mode) to the original transmission mode.
(Reception disabled mode). This reception mode (transmission
Control mode signal from the receiving side
Is emitted, the control command signal is transmitted to the receiver RX. ₁ Received at
Output terminal CTL_OUT To control device 3 (Fig. 1)
The image is input and the imaging device 1 (FIG. 1) is controlled. Control device
3 receives a control command signal and outputs a control response signal
You. This control response signal is supplied to the input terminal ANS_INThrough the initial
Control response signal memory ANS-MEM in the
Be included. Write to control response signal memory ANS-MEM
Control response signal based on the subsequent horizontal synchronization signal
Central processing unit CPU₁ Clock output from
When a predetermined time τ has elapsed since the rise of
The response signal is read from the memory ANS-MEM and the main signal
Added to the transmitter TX₁ Sent from

On the other hand, in the receiving unit 4, when a control command signal is output from the command device 6 (FIG. 1) in the normal reception mode (transmission disabled mode), the control command signal is transmitted via the input terminal CTL _IN. Write to the control command signal memory CTL-MEM in the initialized state. Thereafter, when a horizontal synchronization signal (pulse width t ₁ ) from the transmission side is detected by the main signal detection circuit CW-DET, the central processing unit CPU ₂ sets a predetermined time t ₂ (from the time when the horizontal synchronization signal rises). > T ₁ ), a clock is output to the on / off controller ON / OFF-CTL, and the ultra-low noise amplifier LOW-NOISE-AMP is switched to the inactive state by the on / off controller ON / OFF-CTL, and the communication mode is set. Is switched from the previous reception mode to a mode in which the main signal cannot be received by the receiver RX ₂ , that is, a non-reception mode, and at the same time, the transmitter TX ₂
The mode is switched to a mode in which the control command signal can be transmitted, that is, a transmission mode. The continuation time t ₃ of this transmission mode (reception disabled mode) is determined by the time t
It is set to a value smaller than the subtraction time H-t _{2 to 2} was subtracted. And the central processing unit CPU ₂
When the duration time t ₃ elapses, the on / off controller O
A mode return command signal is output to N / OFF-CTL, and the communication mode is switched from the transmission mode (reception disabled mode) to the original reception mode (transmission disabled mode). In this transmission mode (non-reception mode), the control command signal memory C
Control command signal from the TL-MEM is read out, the control command signal is transmitted to the transmission side from the transmitter TX _2. Thereafter, when the above-mentioned control response signal is transmitted from the transmission side, the reception side separates this control response signal by the control response signal separator ANS-SEP and outputs it to the command device 6.

As described above, the receiving unit 4
Is a control command for controlling the imaging device on the transmission side during a transmission suspension period of the main signal from the transmission side to the reception side (t ₃ : a pause period between horizontal synchronization signals). Send a signal.

If the transmission time of one control command signal is long and the transmission of the entire control command signal cannot be completed within one pause period, the control command signal is divided into a plurality of control command signals over a plurality of pause periods. If the horizontal synchronization signal is lost due to divisional transmission or continuous transmission of the entire control command signal, a function of reproducing the horizontal synchronization signal on the receiving side may be provided.

FIG. 5 shows the transmitting antennas ANT _1-1 and _2-2 and the receiving antennas ANT _1-2 and _2-1 on the transmitting and receiving sides.
FIG.

In FIG. 5, the transmitting antenna ANT
_{1-1 and 2-2} are composed of vertical dipole antennas,
Reception antenna ANT _{1-2 and 2-1} is constituted by a Yagi antenna, by orthogonally the plane of polarization of the polarization plane and the Yagi antenna ANT _{1-2 and 2-1} of the vertical dipole antenna ANT _{1-1, 2-2} I have. And vertical dipole antenna ANT
_{1-1, 2-2} of the feed line 9 of the feed line 8 and the Yagi antenna ANT _{1-2 and 2-1} are provided independently. In such a configuration, the transmitting antennas ANT _1-1 and _2-2 and the receiving antenna ANT
_{By installing 1-2} and _2-1 at the same location, the device can be made compact and the performance can be maintained.

FIG. 6 shows the transmitting antennas ANT _1-1 and _2-2 and the receiving antennas ANT _1-2 and _2-1 on the transmitting and receiving sides.
FIG.

In FIG. 6, transmission antenna ANT
_{1-1 and 2-2} are composed of vertical dipole antennas,
The receiving antennas ANT _{1-2 and 2-1} are constituted by parabolic antennas. As in the configuration of FIG. 5, the feeder 8 for the vertical dipole antennas _ANT1-1 and _{2-2 and} the feeder 9 for the parabolic antennas _{ANT1-2 and 2-1} are provided independently. Even with such a configuration, it is possible to reduce the size and maintain the performance of the device.

FIGS. 7 and 8 show wiring diagrams in the case where the feed lines 8 and 9 on the transmission side and the reception side are unified, respectively. FIG. 7 shows directional elements 10A and 10A such as circulators. The switch shown in FIG. 8 is configured to switch between transmission and reception by using changeover switches 10B and 10B such as pin diodes and relays.

FIGS. 9 and 10 show the transmitting side and the transmitting side, respectively.
Transmission antenna ANT on the receiving side _1-1,2-2 And receiving
Antenna ANT_1-2,2-1 A single vertical dipole antenna
Shows a wiring diagram when shared by
9 shows a directional element 10A such as a circulator.
Is configured to switch between transmission and reception using
Shown are switching switches such as p-i-n diodes and relays.
Is configured to switch between transmission and reception using the switch 10B.
I have. In these cases, an increase in transmission distance cannot be expected, but
In addition, it is excellent in convenience as a simple portable device.

FIG. 11 and FIG. 12 show a configuration diagram of a specific example of the transmission unit 2 and a configuration diagram of a specific example of the reception unit 4 in an image radio transmission apparatus using spread spectrum communication, respectively.

The transmitting unit 2 shown in FIG.
2 basically performs the same operation as the transmitting unit 2 shown in FIG. 2 and the transmitting unit 4 shown in FIG.

That is, in the receiving unit 4, the control command signal from the command device 6 is input to the input terminal CTL _IN , the control command signal memory CTL-MEM, the transmitter T
X ₂ , on / off controller ON / OFF-CTL, and radio frequency power amplifier RF-PA, the output terminal TX during the transmission suspension period of the main signal from the transmission side to the reception side.
Output from _{2 OUT} . In the transmitting unit 2,
Receives the control command signal from the input terminal RX _1, a band-pass filter BPF, ultra low-noise amplifier LOW-NOISE-
AMP, and outputs from an output terminal CTL _OUT via the receiver RX ₁ to the control unit 3. The control device 3 performs control of the imaging device 1, for example, control of the camera or control of the camera platform, in accordance with the control command signal.

In the transmitting unit 2, a control response signal from the control device 3 is input from an input terminal ANS _IN , and a control response signal memory ANS-MEM, a control response signal addition circuit ANS-ADD, a high efficiency code Container CORDE
R, the transmitter TX _1, OFF controller ON / OFF
The signal is inserted into the transmission period of the main signal from the transmission side to the reception side via the radio frequency power amplifier RF-PA and is output from the output terminal _TX2OUT . In the receiving unit 4, the main signal and the control response signal are input to the input terminal RX.
Input from _2IN , band-pass filter BPF, ultra-low noise amplifier LOW-NOISE-AMP, receiver RX ₂ , decoder DECORDER, control response signal separator ANS
-Output from the output terminal ANS _OUT to the command device 6 via the SEP. The command device 6 confirms from the control response signal that the transmitting side has received the control command signal.

On the other hand, the transmitting unit 2
The image signal from the device 1 is supplied to the input terminal S _INInput from
Digitized by analog-to-digital converter ADC
Data pressure by the high-efficiency encoder CORDER.
BASE-BAND modulation (BASE-BAND
-MOD) and spread spectrum modulation (SS-MOD)
Now Transmitter TX₁ , ON / OFF controller ON / OFF
-Via CTL, RF power amplifier RF-PA
Output terminal TX_1OUTOutput from To the receiving unit 4
In this case, the image signal is input to the input terminal RX_2IN Enter from
Filter BPF, ultra-low noise amplifier LOW-NO
Receiver RX via ISE-AMP_Two Demodulated by
Further, the data is decoded by the decoder DECORDER,
Output from analog to analog converter
_OUT To the monitor device 5.

The main signal detection circuit CW-DET as other components, the central processing unit CPU ₁ ,
The CPU ₂ performs the same operation as that of the same reference numerals in FIGS.

The image radio transmission apparatus using spread spectrum communication shown in FIGS. 11 and 12 performs transmission and reception as shown in FIG.

In FIG. 13, when a transmission request command is transmitted from the reception side while the transmission side is in a state of waiting for reception of a transmission request command from the reception side, the transmission request command received by the transmission side is sent to the HDLC (High). -level Data Link
If the packet data is control packet data, the content is analyzed, and if the image data transmission request is addressed to the own station, image transmission is started. After transmitting the image data of a predetermined number of frames (for example, three frames) for a certain period (for example, one second or more), the transmission side waits for reception of the next transmission request command.

On the other hand, the receiving side which has transmitted the transmission request command is in a state of waiting for reception of image data, thereafter receives image data, and when the reception of the image data is completed, transmits the next transmission request command.

Thereafter, the above-described data transmission and reception are repeatedly performed. By including a control command signal for a camera, a camera platform, and the like in the transmission request command, these controls can be performed on the transmission side. On the transmitting side, HDL
If the packet data of C is not received correctly or is not a transmission request addressed to its own pole, transmission of image data is not started. On the receiving side, if image data has not been transmitted for a predetermined period of time, for example, 10 msec after issuing a transmission request, the transmission request command is transmitted again.

In the above-described embodiment, transmission and reception of image signals are mainly described. However, transmission and reception of audio signals can be added.

[0037]

According to the present invention, it is possible to remotely control a camera and a camera platform while staying at a monitoring place.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an image wireless transmission apparatus according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a specific example of a transmitting unit in the embodiment.

FIG. 3 is a configuration diagram of a specific example of a receiving unit in the embodiment.

FIG. 4 is a timing chart for explaining operations of the transmitting unit and the receiving unit.

FIG. 5 is a configuration diagram of a transmitting antenna and a receiving antenna on a transmitting side and a receiving side.

FIG. 6 is another configuration diagram of a transmitting antenna and a receiving antenna on a transmitting side and a receiving side.

FIG. 7 is a wiring diagram in a case where power supply lines on a transmission side and a reception side are unified.

FIG. 8 is another wiring diagram when the power supply lines on the transmission side and the reception side are unified.

FIG. 9 is a wiring diagram in a case where a transmission antenna and a reception antenna on the transmission side and the reception side are shared by one vertical dipole antenna.

FIG. 10 is another wiring diagram in a case where the transmission antenna and the reception antenna on the transmission side and the reception side are shared by one vertical dipole antenna.

FIG. 11 is a configuration diagram of a specific example of a transmitting unit in an image wireless transmission apparatus using spread spectrum communication.

FIG. 12 is a configuration diagram of a specific example of a receiving-side unit in an image wireless transmission device using spread spectrum communication.

FIG. 13 is an explanatory diagram schematically showing transmission and reception of data between the transmitting unit and the receiving unit.

FIG. 14 is a configuration diagram of a conventional image wireless transmission device.

[Explanation of symbols]

ANT _1-2 Receiving antenna on transmitting side ANT _2-2 Transmitting antenna on receiving side 1 Imaging device 2 Transmitting unit 4 Receiving unit

Claims (2)

[Claims] 1. An image radio transmission apparatus for transmitting an image signal over a long distance from a transmission side to a reception side, wherein a transmission antenna is provided on the reception side, and a reception antenna is provided on the transmission side. An image characterized by being configured to transmit a control command signal for controlling an imaging device on a transmission side from a reception side to a transmission side during a transmission suspension period of a main signal and control the imaging device. Wireless transmission device. 2. An image radio transmission apparatus according to claim 1, wherein said transmitting antenna also serves as a receiving antenna, and said receiving antenna also serves as a transmitting antenna.