JP4445405B2 - Signal transmission method and apparatus for wireless camera - Google Patents

Description

  INDUSTRIAL APPLICABILITY The present invention is mainly applied when sports, various events, events, etc. that are performed outdoors are relayed on-site on television, and imaging without a code that regulates the movement of the camera body in order to facilitate the actions of the cameraman. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless camera signal transmission method and apparatus for performing wireless communication, and more particularly to a wireless camera signal transmission method and apparatus to which an optical transmission method is applied.

  Conventionally, as a technique related to a general wireless camera signal transmission device, for example, a wireless reception device and method in which the movable range of a transmission device that performs mobile transmission is expanded to ensure the mobility of the transmission device (see Patent Document 1) ) Establishing a communication protocol that is substantially the same as full-duplex communication without causing any problems in response time and communication efficiency between the wireless imaging device and the receiving base station The control method (refer patent document 2) of the radio | wireless imaging device which can do is mentioned.

  Each of these wireless camera signal transmission devices includes a wireless camera for shooting at the broadcast site of a television broadcast. However, in Patent Document 1, image processing becomes complicated and the entire device becomes expensive. In the case of Patent Document 2, there is a problem that the number of parts in the constituent parts is too large and the entire apparatus becomes large.

  Therefore, as another technique related to the signal transmission device for wireless camera for solving such a problem, for example, a configuration using an optical transmission system as shown in FIG. That is not the invention). This wireless camera signal transmission device generates an optical signal according to a radio output signal obtained by receiving an imaging radio signal from a wireless camera 11 for on-site television relaying by an antenna 15, and faces the wireless camera 11. And the antenna unit 42 arranged in the same manner, and the optical / electricity (O) that is coupled to the antenna unit 42 via the optical composite cable 13 and converts the optical signal into a radio frequency imaging data signal (electrical signal). / E) The relay point 24 having the converter 17 is provided.

  Among these, the wireless camera 11 needs to widen the frequency allocation and the transmission band, and is required to have a wider bandwidth particularly in order to be applied to the high-definition method. Therefore, the antenna used for the camera body is downsized. The operating frequency is 7 GHz band above.

  As described above, the antenna unit 42 includes the antenna 15 that receives an imaging radio signal in the 7 GHz band from the wireless camera 11 to which the high-definition method is applied and outputs a radio output signal. In addition, the power unit 29 that supplies power to each unit A demodulator 30 which is supplied with power from the power supply unit 29 and demodulates the radio output signal from the antenna 15 and converts it into an intermediate frequency (IF) signal and outputs it, and is supplied with power from the power supply unit 29 to drive the laser. And a laser generator having a laser diode (LD) for generating an optical signal by a laser in accordance with an intermediate frequency signal from a demodulator 30 in accordance with the drive signal from the laser drive circuit 26 25.

JP 2002-84261 A (summary) Japanese Unexamined Patent Publication No. 2003-289817 (Abstract)

  In the case of the wireless camera signal transmission apparatus to which the optical transmission system shown in FIG. 4 described above is applied, a laser diode of a laser generator is used in the antenna unit as the wireless camera uses a radio frequency imaging radio signal of 7 GHz. Therefore, it is necessary to provide a demodulator for demodulating the radio output signal and converting it to an intermediate frequency signal. There is a limit in reducing the size and weight of the unit, and there is a problem that it is difficult to always move the antenna unit to a range with a good view so that the wireless camera is appropriately tracked and placed oppositely. .

  That is, the antenna unit in the wireless camera signal transmission device is not required to be as portable as a wireless camera, but in a high frequency band as high as 7 GHz, the straightness of radio waves is too high. For example, if the wireless camera is hidden in the shadow, the radio wave will not reach the antenna unit. Therefore, in order to eliminate such inconvenience, the antenna unit is reduced in size and weight, and the portability is improved to some extent. The wireless camera can always be tracked and moved, but if the antenna unit has a demodulator, there is a limit to downsizing and weight reduction, which makes it difficult to track the wireless camera. There is.

  In addition, in the case of the current wireless camera signal transmission method, the wireless output signal received by the antenna unit unit is difficult because the antenna unit unit having the demodulator as described above is difficult to track and move with respect to the wireless camera. Has a drawback that it is difficult to transmit the optical signal to the relay point as an optical signal with a high degree of freedom.

  The present invention has been made to solve such problems, and its technical problem is to stably relay the optical output signal received on the antenna unit side as an optical signal without demodulating it. An object of the present invention is to provide a wireless camera signal transmission method capable of long-distance transmission to a point, and a wireless camera signal transmission apparatus including the portable antenna unit to which the wireless camera signal transmission method is applied.

  According to the present invention, an optical signal corresponding to a radio output signal obtained by receiving an imaging radio signal from the wireless camera is generated on the side of the antenna unit disposed opposite to the wireless camera and then passed through the optical cable. A wireless camera signal transmission method in which the optical signal is converted into a radio frequency electrical signal on the relay point side after being transmitted to the relay point side, and the antenna unit unit side receives an imaging radio signal with an antenna. A wireless signal receiving stage for outputting a wireless output signal, and performing optical modulation on an unmodulated optical signal using the wireless output signal as it is without performing frequency conversion or modulation system conversion. A radio frequency optical modulation stage to generate, and an optical modulation signal transmission stage for transmitting the optical modulation signal to the relay point side via an optical cable, The relay point side, the wireless camera signal transmission method having a radio frequency signal restoration step of restoring the image pickup data signal in a radio frequency modulated optical signal and converts the optical / electric is obtained.

  Further, according to the present invention, in the above wireless camera signal transmission method, the relay point side has a control signal transmission stage for another antenna unit for transmitting a control signal for the wireless camera to another antenna unit side. On the side of the antenna unit, a wireless camera signal transmission method having a separate antenna unit side control signal transmission step of transmitting a control signal to the wireless camera can be obtained.

  On the other hand, according to the present invention, an optical signal is generated according to a radio output signal obtained by receiving an imaging radio signal from a wireless camera, and an antenna unit unit disposed opposite to the wireless camera, and an antenna In a wireless camera signal transmission device that is coupled to a unit unit via an optical cable and includes a relay point that converts an optical signal into a radio frequency electrical signal, the antenna unit unit receives an imaging radio signal. An antenna for obtaining a wireless output signal, and light for generating an optical modulation signal by optically modulating an unmodulated optical signal using the wireless output signal as it is without changing the frequency or modulation method. The relay point is an optical / electrical converter that converts the optical modulation signal transmitted from the antenna unit section via the optical cable. Wireless Camera signal transmission system having an optical / electrical converter to restore the image pickup data signal frequency.

According to the present invention, in the signal transmission device for a wireless camera, an optical waveguide type LiNbO ₃ optical modulator made of LiNbO ₃ crystal is used as the optical modulator, and the relay point is an optical modulation signal in the optical modulator. A power supply unit for supplying power, a laser drive circuit for outputting a drive signal supplied with power from the power supply unit to drive the laser, and driving from the laser drive circuit A laser generator that generates an unmodulated optical signal in accordance with the signal and transmits the unmodulated optical signal to the optical modulator via an optical cable. Further, the optical waveguide type LiNbO ₃ optical modulator is configured so that an unmodulated optical signal is transmitted by a wireless output signal. A signal transmission apparatus for a wireless camera that generates a light modulation signal by receiving the modulation is obtained.

  Furthermore, according to the present invention, in the signal transmission device for a wireless camera, an electro / optical modulator is used as the optical modulator, the antenna unit unit includes a power source unit for supplying power and a power source from the power source unit. A laser drive circuit that outputs a drive signal for driving the laser that is supplied, a laser generator that generates an unmodulated optical signal in accordance with the drive signal from the laser drive circuit, and an unmodulated signal that is supplied with power from a power supply unit An amplifier that amplifies and adjusts the intensity of the optical signal, and the electrical / optical modulator performs electrical / optical modulation by modulating an unmodulated optical signal with a wireless output signal to generate an optical modulated signal Thus, a wireless camera signal transmission apparatus can be obtained.

  In addition, according to the present invention, in the signal transmission device for a wireless camera, an electrical / optical modulator is used as the optical modulator, and the relay point causes the optical modulator to generate an optical modulation signal. A power supply unit for supplying power, a laser drive circuit for outputting a drive signal supplied with power from the power supply unit to drive the laser, and an unmodulated light according to the drive signal from the laser drive circuit A laser generator that generates a signal and transmits it to the optical modulator via an optical cable. The antenna unit has a power supply that supplies power, and amplifies the intensity of the unmodulated optical signal that is supplied with power from the power supply. And an electric / optical modulator that modulates an unmodulated optical signal with a wireless output signal to generate an optical modulation signal by performing electric / optical modulation. Camera signal transmission device can be obtained.

  On the other hand, according to the present invention, in any one of the above wireless camera signal transmission devices, the relay point transmits a control signal for the wireless camera to another antenna unit, and the other antenna unit transmits the control signal. A signal transmission device for a wireless camera that transmits to a wireless camera is obtained.

In the case of the signal transmission method for a wireless camera of the present invention, on the antenna unit side, an imaging radio signal in the 7 GHz band from a wireless camera to which a high-definition method is applied is received by the antenna at the radio signal reception stage and output as a radio output signal. In the subsequent radio frequency optical modulation stage, optical modulation is performed by optically modulating an unmodulated optical signal using the radio output signal as it is without performing frequency conversion or modulation system conversion (not demodulating). After generating the signal, the optical modulation signal is transmitted to the relay point side (optical transmission) via the optical cable in the optical modulation signal transmission stage, and the optical modulation signal is transmitted to the optical / electrical signal in the radio frequency signal restoration stage on the relay point side. (O / E) is converted and restored as a radio frequency imaging data signal. Stably without demodulating the radio output signal received on the side to the relay point as high degree of freedom optical signal becomes adapted to long-distance transmission. That is, according to this wireless camera signal transmission method, it is well known that the wireless camera is portable and has a high degree of freedom of movement. On the other hand, the antenna unit side that follows it is also reduced in size and weight. By being able to implement, it plays the role of expanding the range of action of the wireless camera, and because the optical transmission is performed to the relay point side with the radio frequency on the antenna unit side, as a result, between the antenna unit side and the relay point side Optical transmission can easily be carried out without repeating over several kilometers. On the other hand, in the signal transmission device for a wireless camera of the present invention to which such a method is applied, the antenna unit portion does not have a demodulator that restricts portability, and is a waveguide type optical modulator capable of direct modulation at 7 GHz. LiNbO ₃ optical modulators or electric / optical (E / O) modulators are provided, and these optical modulators do not perform frequency conversion or modulation system conversion (without demodulation) on the radio output signal obtained by the antenna. ) The optical modulation signal generated by optically modulating an unmodulated optical signal using the radio frequency is transmitted (optical transmission) to the relay point via the optical cable, and the optical modulation signal is transmitted to the optical / electrical point at the relay point. (O / E) Conversion and restoration as radio frequency imaging data radio signal, so the antenna unit did not perform frequency conversion or modulation system conversion (demodulation) at all Therefore, the configuration can be simplified to reduce the power consumption, and the size and weight can be reduced. As a result, the power that must be sent by the optical cable is reduced compared to the case of the conventional device, and even a thin optical cable has a longer distance. In addition to being able to transmit, the optical cable is also lighter and more portable, which can contribute to the portability of the antenna unit and the longer transmission distance, and the wireless camera is often tracked and moved. It is also possible to increase the reliability of optical transmission by reducing the number of parts (particularly active elements) used in the antenna unit where vibration is applied. In any of the wireless camera signal transmission method and apparatus of the present invention, the relay point transmits a control signal for the wireless camera to another antenna unit, and the other antenna unit transmits the control signal to the wireless camera. As a result, it is possible to accurately collate between the relay point and the imaging range of the wireless camera, and the trouble of the cameraman's wireless camera due to a setting error of the imaging range is reduced, and the image provided by the on-site television relay is reduced. Quality and safety can be improved.

  The wireless camera signal transmission method according to the best mode of the present invention is a radio signal for 7 GHz band imaging from a wireless camera on the side of an antenna unit disposed opposite to a wireless camera to which a high-definition system for on-site television relaying is applied. When an optical signal corresponding to a wireless output signal obtained by receiving the signal is generated and transmitted to the relay point side via an optical cable, the optical unit converts the optical signal into a radio frequency electrical signal on the relay point side. On the part side, a radio signal receiving stage that receives an imaging radio signal with an antenna and outputs a radio output signal, and an unmodulated optical signal using the radio output signal as it is without performing frequency conversion or modulation system conversion A radio frequency optical modulation stage for generating an optical modulation signal by optically modulating the optical modulation signal to the optical modulation signal via an optical cable. A radio frequency signal restoring stage that transmits the modulated optical signal to the relay point side by optical / electrical (O / E) conversion to restore the radio frequency imaging data signal. It has a stage.

  However, in the case of this wireless camera signal transmission method, in order to accurately check the relay point and the imaging range of the wireless camera, the relay point side transmits a control signal for the wireless camera to another antenna unit side. It is preferable to have a control signal transmission stage for the antenna unit, and to have another antenna unit side signal transmission stage for transmitting the control signal to the wireless camera on the other antenna unit side.

  On the other hand, in the signal transmission device for a wireless camera of the present invention to which such a method is applied, according to a wireless output signal obtained by receiving a radio signal taken in the 7 GHz band from a wireless camera to which a high-definition system for on-site television relay is applied. An optical signal is generated, and an antenna unit unit disposed opposite to the wireless camera and a relay point coupled to the antenna unit unit via an optical cable and converting the optical signal into an electrical signal are provided. In addition, for the antenna unit part, an antenna for receiving an imaging radio signal and obtaining a radio output signal, and using the radio output signal as it is without changing the frequency or modulation method And an optical modulator that generates an optical modulation signal by optically modulating an unmodulated optical signal. Te are those having a light-electric converter to restore the image pickup data signal in a radio frequency modulated optical signal transmitted by converting optical / electrical (O / E) from the antenna unit section through an optical cable.

However, even in the case of a signal transmission device for a wireless camera, the relay point transmits a control signal for the wireless camera to another antenna unit unit in order to accurately check the relay point and the imaging range of the wireless camera. The another antenna unit part preferably transmits the control signal to the wireless camera. The optical modulator is preferably an optical waveguide type LiNbO ₃ optical modulator or an electric / optical (E / O) modulator.

  FIG. 1 is a block diagram showing a basic configuration of a wireless camera signal transmission device according to a first embodiment of the present invention.

  In the case of this wireless camera signal transmission device, compared with the conventional device shown in FIG. 4, it is obtained by receiving an imaging radio signal in the 7 GHz band from the wireless camera 11 to which a high-definition system for relaying on-site television is applied by the antenna 15. An optical signal is generated in accordance with the wireless output signal, and the antenna unit unit 12 disposed opposite to the wireless camera 11 is coupled to the antenna unit unit 12 via the optical composite cable 13 and the optical signal. A common functional configuration is common in that it includes a relay point 14 having an optical / electrical (O / E) converter 17 that converts an electrical signal into a radio frequency electrical signal.

However, the antenna unit 12 here does not have a demodulator 30 and optically modulates an unmodulated optical signal using the radio output signal as it is without changing the frequency or modulation method. Thus, only the optical modulator 16 that generates the optical modulation signal is provided, and the relay point 14 converts the optical modulation signal transmitted from the antenna unit 12 through the optical composite cable 13 into optical / electrical (O / E). ) Means for generating an optical modulation signal in the optical modulator 16 in the antenna unit 12 other than the optical / electrical (O / E) converter 17 described above that converts and restores as a radio frequency imaging data radio signal. A power supply unit 20 for supplying power, a laser drive circuit 19 that outputs a drive signal for driving the laser when power is supplied from the power supply unit 20, and A laser generator 18 having a laser diode (LD) for generating an unmodulated optical signal in accordance with a drive signal from the user drive circuit 19 and transmitting it to the optical modulator 16 in the antenna unit section 2 via the optical composite cable 13; The detailed functional configuration is greatly different from that of the conventional apparatus shown in FIG. The optical modulator 16 provided in the antenna unit 12 here is an optical waveguide type LiNbO ₃ optical modulator made of LiNbO ₃ crystal, and an unmodulated optical signal transmitted from the laser generator 18 is used. Has a function capable of generating an optical modulation signal by being modulated by the wireless output signal transmitted from the antenna 15.

That is, in the case of the signal transmission device for a wireless camera according to the first embodiment, the antenna unit 12 receives an imaging radio signal from the wireless camera 11 by the antenna 15 and the radio output signal obtained here is directly LiNbO _3. The light is transmitted to the optical modulator 16 using crystals. On the other hand, at the relay point 14, the laser drive circuit 19 supplied with power from the power supply unit 20 outputs a drive signal for driving the laser, and the laser diode (LD) is turned on according to the drive signal from the laser drive circuit 19. The laser generator 18 has an unmodulated optical signal (emits light) and transmits the unmodulated optical signal to the optical modulator 16 in the antenna unit section 12 via the optical composite cable 13.

  Therefore, the optical modulator 16 generates an optical modulation signal modulated at a radio frequency by modulating an unmodulated optical signal that has arrived from the relay point 14 with a radio output signal from the antenna 15, and generates the optical modulation signal. Is again transmitted to the optical / electrical (O / E) converter 17 at the relay point 14 via the optical composite cable 13. When this optical modulation signal is input to the optical / electrical (O / E) conversion unit 17 of the relay point 14, the optical / electrical (O / E) conversion is performed here to restore it as a radio frequency imaging data wireless signal. Is output.

In the case of the wireless camera signal transmission device according to the first embodiment, compared to the configuration of the conventional device shown in FIG. 4, the device configuration on the relay point 14 side is complicated and enlarged, and the power consumption increases. In general, since the relay point 14 itself is installed in a relay vehicle or the like, the size and power consumption of the device do not become a big problem. In exchange for this, on the antenna unit 12 side, since the interior excluding the antenna 15 is configured only by the optical modulator 16, the device configuration is reduced in size and weight, and the optical modulator 16 includes an optical waveguide type LiNbO. _{The use of a three-} light modulator eliminates the need for a power supply unit (power supply unit 29 as in the case of the device configuration of FIG. 4) for supplying power to the antenna unit unit 12, making it extremely compact and lightweight. It has become a system configuration. Therefore, according to the signal transmission apparatus for a wireless camera according to the first embodiment, an optical signal (optical signal) is stably and highly flexible without demodulating a radio output signal received by the antenna unit 12 itself using a demodulator. As a modulation signal, the signal can be transmitted over a long distance (optical transmission) to the relay point 14 and is extremely portable.

  FIG. 2 is a block diagram showing a basic configuration of a wireless camera signal transmission device according to a second embodiment of the present invention.

  Even in the case of this wireless camera signal transmission device, compared to the conventional device shown in FIG. The optical unit generates an optical signal according to the obtained wireless output signal, and is coupled to the antenna unit unit 22 disposed facing the wireless camera 11 via the optical composite cable 13. A configuration including a relay point 24 (the same configuration as that of the conventional device shown in FIG. 4) having an optical / electrical (O / E) converter 17 for converting an optical signal into a radio frequency electrical signal, and an antenna unit section As for the antenna 22, the power unit 29 for supplying power as in the case of the antenna unit unit 42, and the power source 29 supplies power. A laser drive circuit 26 that outputs a drive signal for driving the laser, and a laser generator 25 that generates an unmodulated optical signal in accordance with the drive signal from the laser drive circuit 26. Common functional structure is common.

  However, the antenna unit 22 here does not have a demodulator 30 and optically modulates an unmodulated optical signal by using the radio output signal as it is without changing the frequency or modulation method. Thus, a detailed functional configuration is shown in that it includes an optical modulator 27 that generates an optical modulation signal and an amplifier 28 that is supplied with power from a power supply unit 29 and amplifies and adjusts the intensity of an unmodulated optical signal. This is different from the conventional apparatus shown in FIG. Here, an electrical / optical (E / O) modulator is used for the optical modulator 27 provided in the antenna unit 22 here, and an electrical signal is modulated by modulating an unmodulated optical signal with a radio output signal. / Has a function capable of generating an optical modulation signal by performing optical (E / O) modulation.

That is, in the case of the signal transmission device for a wireless camera according to the second embodiment, the optical modulator 27 that performs electro / optical (E / O) conversion is used instead of the optical modulator 16 using the LiNbO ₃ crystal according to the first embodiment. In the antenna unit 22, the imaging radio signal from the wireless camera 11 is received by the antenna 15, and the radio output signal obtained here is directly converted into an optical modulator 27 by an electric / optical (E / O) modulator. In addition, an unmodulated optical signal generated (emitted) by the laser generator 25 according to the drive signal output from the laser drive circuit 26 supplied with power from the power supply unit 29 is similarly transmitted to the optical modulator 27. The

  Therefore, in the optical modulator 27, electric / optical (E / O) modulation is performed by modulating an unmodulated optical signal whose intensity is adjusted by the amplifier 28 supplied with power from the power supply unit 29 with a wireless output signal. Then, an optical modulation signal is generated, and the optical modulation signal modulated at the radio frequency is transmitted to the relay point 24 via the optical composite cable 13. The optical modulation signal transmitted to the relay point 24 is input to the optical / electrical (O / E) conversion unit 17 and is subjected to optical / electrical (O / E) conversion to be restored and output as a radio frequency imaging data wireless signal. Is done.

  In the case of the signal transmission device for a wireless camera according to the second embodiment, compared with the configuration of the conventional device shown in FIG. 4, the configuration of the antenna unit 22 includes the laser generator 25 and thus cannot be made power-free. By providing the optical modulator 27 and the amplifier 28 in addition to the partial power supply unit 29, the laser drive circuit 26, and the laser generator 25, the number of components itself increases, but the conventional apparatus shown in FIG. Since the demodulator 30 does not have to be provided as in the case, the apparatus configuration can be reduced in size, weight, and power consumption. Therefore, also in the case of the wireless camera signal transmission apparatus according to the second embodiment, the antenna unit 22 itself can stably and highly flexibly convert the optical output signal received by the antenna unit 22 itself into an optical signal (optical modulation signal). It becomes a portable thing which can carry out long distance transmission (optical transmission) to the relay point 24.

  FIG. 3 is a block diagram showing a basic configuration of a wireless camera signal transmission device according to a third embodiment of the present invention.

  Even in the case of this wireless camera signal transmission device, compared with the conventional device shown in FIG. 4, the antenna 15 receives an imaging radio signal in the 7 GHz band from the wireless camera 11 to which a high-definition system for relaying on-site television is applied. The optical unit generates an optical signal according to the obtained wireless output signal, and is coupled to the antenna unit 32 disposed opposite to the wireless camera 11 via the optical composite cable 13. A relay point 14 having the optical / electrical (O / E) converter 17 that converts an optical signal into an electrical signal of a radio frequency (the same configuration as that of the apparatus according to the first embodiment shown in FIG. 1); Further, the antenna unit section 22 has a power supply section 29 for supplying power as in the case of the antenna unit section 42. At point, cause functional configuration is common.

  However, the antenna unit 32 here does not have a demodulator 30 and optically modulates an unmodulated optical signal using the radio output signal as it is without changing the frequency or modulation method. Thus, an optical modulator 27 that generates an optical modulation signal and an amplifier 28 that is supplied with power from a power supply unit 29 and amplifies and adjusts the intensity of an unmodulated optical signal are provided. As described above, except that the optical / electrical (O / E) converter 17 is provided, the power supply unit 20, the laser drive circuit 19, and the laser, which are means for generating the optical modulation signal in the optical modulator 16 in the antenna unit unit 12. The detailed functional configuration is greatly different from that of the conventional apparatus shown in FIG. 4 in that the generator 18 is provided.

  That is, in the case of the wireless camera signal transmission device according to the third embodiment, the device configuration of the second embodiment is modified and applied to the configuration of the device configuration of the first embodiment. An imaging radio signal from the wireless camera 11 is received by the antenna 15, and a radio output signal obtained here is directly transmitted to the optical modulator 27 using an electric / optical (E / O) modulator. On the other hand, at the relay point 14, the laser drive circuit 19 supplied with power from the power supply unit 20 outputs a drive signal for driving the laser, and the laser diode (LD) is turned on according to the drive signal from the laser drive circuit 19. The laser generator 18 has an unmodulated optical signal (emits light), and this unmodulated optical signal is sent to the optical modulator 27 in the antenna unit section 32 via the optical composite cable 13 and the power supply unit 29 and the amplifier 28. To transmit via.

  Therefore, in the optical modulator 27, electric / optical (E / O) modulation is performed by modulating an unmodulated optical signal whose intensity is adjusted by the amplifier 28 supplied with power from the power supply unit 29 with a wireless output signal. Then, an optical modulation signal is generated, and the optical modulation signal modulated at the radio frequency is transmitted to the relay point 14 via the optical composite cable 13. The optical modulation signal transmitted to the relay point 14 is input to the optical / electrical (O / E) conversion unit 17 and is subjected to optical / electrical (O / E) conversion to be restored and output as a radio frequency imaging data wireless signal. Is done.

  In the case of the wireless camera signal transmission device according to the third embodiment, the configuration of the antenna unit 32 is an unmodulated optical signal from the laser generator 18 at the relay point 14 as compared with the configuration of the conventional device shown in FIG. Since the amplifier 28 for amplifying and adjusting the intensity of the power is required, the power can not be reduced. However, the common part is only the power supply unit 29 and the demodulator 30 and the laser driving circuit 26 which are necessary in the conventional apparatus are used. The optical generator 27 and the amplifier 28 may be provided without using the laser generator 25, and the number of components is somewhat reduced, and the demodulator 30 is provided as in the case of the conventional apparatus shown in FIG. Since it is not necessary, it is possible to achieve a device configuration that is reduced in size, weight, and power consumption. Therefore, also in the case of the wireless camera signal transmission apparatus according to the third embodiment, the antenna unit 32 itself can be stably and highly flexible as an optical signal (optical modulation signal) without demodulating the radio output signal received. The port can be transported to the relay point 24 for a long distance (optical transmission).

  In addition, although description was abbreviate | omitted in the signal transmission apparatus for wireless cameras which concerns on each Example mentioned above, in any case, the relay points 14 and 24 transmit the control signal with respect to the wireless camera 11 to another antenna unit part which is not illustrated. If another antenna unit unit has a function of transmitting a control signal to the wireless camera 11, it is possible to accurately check the relay points 14 and 24 and the imaging range of the wireless camera 11.

It is the block diagram which showed the basic composition of the signal transmission apparatus for wireless cameras which concerns on Example 1 of this invention. It is the block diagram which showed the basic composition of the signal transmission apparatus for wireless cameras which concerns on Example 2 of this invention. It is the block diagram which showed the basic composition of the signal transmission apparatus for wireless cameras which concerns on Example 3 of this invention. It is the block diagram which showed the basic composition of the signal transmission apparatus for conventional wireless cameras.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Wireless camera 12, 22, 32, 42 Antenna unit part 13 Optical composite cable 14, 24 Relay point 15 Antenna 16, 27 Optical modulator 17 Optical / electrical (O / E) converter 18, 25 Laser generator 19, 26 Laser drive circuit 20, 29 Power supply unit 28 Amplifier 30 Demodulator

Claims (7)

  An optical signal corresponding to a radio output signal obtained by receiving an imaging radio signal from the wireless camera is generated on the antenna unit side arranged facing the wireless camera, and then transmitted to the relay point side via an optical cable. Then, a wireless camera signal transmission method for converting the optical signal into a radio frequency electrical signal on the relay point side, wherein the antenna unit unit side receives the imaging radio signal with an antenna and outputs the radio signal A radio signal reception stage for outputting a signal, and an optical modulation signal is generated by optically modulating an unmodulated optical signal using the radio output signal as it is without performing frequency conversion or modulation system conversion. A radio frequency optical modulation stage; and an optical modulation signal transmission stage for transmitting the optical modulation signal to the relay point side via the optical cable. Has the door, the relay point side, the wireless camera signal transmission method characterized by having a radio frequency signal restoration step of restoring the image pickup data signal in a radio frequency said optical modulation signal by the optical / electrical conversion.   The wireless camera signal transmission method according to claim 1, further comprising: a control signal transmission step for another antenna unit that transmits a control signal for the wireless camera to another antenna unit unit side on the relay point side. A signal transmission method for a wireless camera, comprising: a separate antenna unit side control signal transmission step for transmitting the control signal to the wireless camera on the antenna unit side.   An optical signal is generated according to a radio output signal obtained by receiving an imaging radio signal from a wireless camera, and an antenna unit portion disposed opposite to the wireless camera, and an optical cable for the antenna unit portion And a relay point for converting the optical signal into an electric signal of a radio frequency, wherein the antenna unit unit receives the imaging radio signal and outputs the radio signal An antenna for obtaining a signal, and an optical modulator that generates an optical modulation signal by optically modulating an unmodulated optical signal by using the radio output signal as it is without changing the frequency or modulation method. And the relay point receives the optical modulation signal transmitted from the antenna unit section via the optical cable. / Wireless camera signal transmission apparatus comprising the electro-converted light-electrical converter to restore the image pickup data signal in a radio frequency. 4. The signal transmission device for a wireless camera according to claim 3, wherein an optical waveguide type LiNbO ₃ optical modulator made of LiNbO ₃ crystal is used as the optical modulator, and the relay point is the optical modulation signal in the optical modulator. A power supply unit for supplying power, a laser drive circuit for outputting a drive signal supplied with power from the power supply unit to drive a laser, and the laser drive circuit A laser generator that generates the unmodulated optical signal in accordance with the drive signal and transmits the unmodulated optical signal to the optical modulator via the optical cable, and the optical waveguide type LiNbO ₃ optical modulator further comprises The optical signal is modulated by the wireless output signal to generate the optical modulation signal. Location.   4. The signal transmission device for a wireless camera according to claim 3, wherein an electric / optical modulator is used as the optical modulator, and the antenna unit unit includes a power source unit for supplying power and power supply from the power source unit. A laser driving circuit for outputting a driving signal for driving the laser, a laser generator for generating the unmodulated optical signal in accordance with the driving signal from the laser driving circuit, and a power supply from the power supply unit. An amplifier that amplifies and adjusts the intensity of the unmodulated optical signal, and the electrical / optical modulator performs electrical / optical modulation by modulating the unmodulated optical signal with the wireless output signal. A signal transmission device for a wireless camera, which generates the light modulation signal.   4. The signal transmission apparatus for a wireless camera according to claim 3, wherein an electrical / optical modulator is used as the optical modulator, and the relay point causes the optical modulator to generate the optical modulation signal. Means for supplying power, a laser drive circuit for outputting a drive signal supplied with power from the power supply unit to drive a laser, and the non-drive according to the drive signal from the laser drive circuit. A laser generator that generates a modulated optical signal and transmits the modulated optical signal to the optical modulator via the optical cable, and the antenna unit unit includes a power supply unit that supplies power and a power supply unit that is supplied with power from the power supply unit. An amplifier that amplifies and adjusts the intensity of the modulated optical signal, and the electrical / optical modulator modulates the unmodulated optical signal by the wireless output signal, thereby changing the electrical / optical modulation. For wireless camera signal transmission apparatus characterized by the performing and generates the optical modulation signal. The wireless camera signal transmission device according to any one of claims 3 to 6, wherein the relay point transmits a control signal for the wireless camera to another antenna unit unit, and the other antenna unit unit includes: A signal transmission device for a wireless camera, wherein the control signal is transmitted to the wireless camera.

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