JP2005319097A - Transmission device and introduction system into subject - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission device capable of reducing malfunction caused by a gap included in a transmitted radio signal. <P>SOLUTION: A capsule type endoscope 2 functioning as the transmission device comprises an intra-subject information obtaining part 21 for obtaining the intra-subject information, a signal processing part 22 for generating and outputting an information main component based on the obtained intra-subject information, a dummy component output part 23 for generating and outputting a dummy component including an A.C. signal with a prescribed frequency at the timing corresponding to the gap between the information main components, an addition part 24 for synthesizing the information main component and the dummy component, and a radio-transmission part 25 for transmitting the signal synthesized by the addition part 24 to the outside. As the dummy component is inserted into the gap between the information main components, the frequency band of the transmitted radio signals is narrowed and the fluctuation of the average level of the radio signals is inhibited. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transmission device that transmits a radio signal including at least an information main body portion to the outside or an in-subject introduction system including a transmission device.

  In recent years, in the field of endoscopes, swallowable capsule endoscopes have been proposed. This capsule endoscope is provided with an imaging function and a wireless communication function. The capsule endoscope is swallowed from the mouth of the subject for observation (examination) until it is spontaneously discharged until it is spontaneously discharged. It has the function of moving and capturing images sequentially.

  While moving inside the body cavity, image data captured inside the body by the capsule endoscope is sequentially transmitted to the outside by wireless communication and stored in a memory provided outside. By carrying a receiver having a wireless communication function and a memory function, the subject can freely act after swallowing the capsule endoscope and before being discharged. After the capsule endoscope is ejected, a doctor or a nurse can make a diagnosis by displaying an image of an organ on a display based on image data stored in a memory (see, for example, Patent Document 1). .)

  By the way, in the conventional capsule endoscope system, the image data captured by the capsule endoscope is wirelessly transmitted with the same data configuration as that of the image transmission by the NTSC system, for example. That is, the image data transmitted in the conventional capsule endoscope system corresponds to the data corresponding to a predetermined scanning line and the scanning line adjacent to the predetermined scanning line with respect to the image data constituting one screen. A so-called horizontal blanking period is provided between the data. The horizontal blanking period is originally provided as a gap period in order to prevent a blank line from being displayed in the image display on the cathode ray tube, and the radio signal transmitted from the capsule endoscope is the gap period. Is formed with a gap portion formed by a DC component corresponding to High or Low in the digital signal.

Japanese Patent Laying-Open No. 2001-231186 (page 3, FIG. 1)

  However, the conventional capsule endoscope system has a problem that the wireless signal transmitted from the capsule endoscope has a gap portion. Hereinafter, a problem caused by the inclusion of a gap in the radio signal will be described in detail.

  First, due to the presence of the gap portion, in the conventional capsule endoscope system, when AC coupling is used in a signal processing circuit or the like in the receiver, a problem due to instantaneous voltage change occurs. That is, the information body portion contains a signal component having a predetermined amplitude corresponding to the image data, the information body portion has an average level corresponding to the signal component, while the gap portion corresponds to High or Low. A constant voltage. Therefore, the average level of the information body part and the average level of the gap part (that is, the voltage level corresponding to High or Low) are usually different by a certain amount. In a receiver that receives such a radio signal, In order to reduce the offset amount according to the voltage difference, an AC coupling circuit including a capacitor or the like is used.

  When such an AC coupling circuit is used for a receiver in a capsule endoscope system, an instantaneous voltage change such as a sag becomes a problem. That is, in the radio signal transmitted from the capsule endoscope, the image data corresponding to one image has a configuration in which the information main body portion and the gap portion are repeated, so that voltage fluctuations frequently occur. There is a problem that there may be a problem in following the AC coupling circuit.

  Further, the conventional capsule endoscope system has a problem that it is difficult for a receiver to remove noise components from received radio signals. As described above, since the gap portion is constituted by a DC component of a constant voltage, the radio signal transmitted from the capsule endoscope includes a low frequency component corresponding to the gap portion at a predetermined ratio. It becomes. In other words, the horizontal blanking period during which a DC signal with a constant intensity is output usually lasts for several hundreds of microseconds, so the radio signal inevitably contains low-frequency components corresponding to the length of time it takes. It becomes.

  On the other hand, the receiver is usually provided with a frequency filter for removing noise components from the received radio signal and extracting only the radio signal transmitted from the capsule endoscope. Since such a frequency filter has a function of extracting a frequency component in a band corresponding to the frequency of the radio signal transmitted from the capsule endoscope, the radio signal includes a low frequency component corresponding to the gap portion, A need arises to use a wideband frequency filter to transmit even such low frequency components. This leads to a reduction in the noise component removed by the frequency filter. Therefore, it is not appropriate that the low frequency component is included in the radio signal from the viewpoint of effectively functioning the frequency filter.

  The present invention has been made in view of the above, and includes a transmission device that reduces inconvenience caused by a gap portion included in a transmitted radio signal, and an intra-subject in which such a transmission device is applied to an intra-subject introduction device. The purpose is to realize the introduction system.

  In order to solve the above-described problems and achieve the object, a transmission device according to claim 1 is a transmission device that transmits a radio signal including at least an information body portion to the outside, and includes the information body portion. An information body output means for outputting a signal, a dummy component output means for outputting a dummy component formed by one or more alternating current signals having a predetermined frequency component, and the information body portion in a signal including the information body portion Dummy insertion means for inserting the dummy component into at least a part of the non-existing gap portion, and wireless transmission means for wirelessly transmitting a signal including the information main body portion into which the dummy component is inserted to the outside It is characterized by that.

  According to the first aspect of the present invention, the gap portion is provided by the dummy insertion means for inserting the dummy component formed by the AC signal with respect to the gap portion generated between the information body components output from the information body output means. Compared to the case where only the DC component is used, the frequency band of the radio signal to be transmitted can be narrowed, and the difference in the average level between the information body component and the gap portion can be reduced. It becomes.

  According to a second aspect of the present invention, in the transmission apparatus according to the second aspect, the dummy component is formed by an AC signal having an average level substantially matching an average level of a signal including the information main body portion.

  According to a third aspect of the present invention, in the transmission apparatus according to the third aspect, the dummy component is formed by an AC signal having an average frequency substantially coincident with an average frequency of a signal including the information main body portion.

  According to a fourth aspect of the present invention, in the above invention, the dummy component is formed by a predetermined fixed pattern.

  According to a fifth aspect of the present invention, in the above transmission device, the dummy component is formed by a clock signal having a constant frequency.

  According to a sixth aspect of the present invention, in the above invention, the dummy component is formed using a pseudo-noise code.

  In the transmitter according to claim 7, in the above invention, the dummy inserting unit includes the information main body portion of the signal output from the information main body output unit and the dummy output from the dummy component output unit. An addition means for combining the components is provided.

  Further, in the transmission device according to claim 8, in the above invention, the dummy insertion unit outputs a signal component output to the wireless transmission unit based on a predetermined timing based on the information main body portion and the dummy component. Switching means for switching between and is provided.

  According to a ninth aspect of the present invention, in the above invention, the signal including the information body portion is an image signal, and the gap portion is a horizontal blanking period.

  The transmission device according to claim 10 is the above-described invention, wherein the transmission device has a function of acquiring in-subject information by being introduced into the subject, and the information main body generation portion includes the subject It is characterized by being formed including inside information.

  In addition, an in-subject introduction system according to an eleventh aspect is introduced into a subject, and an in-subject introduction device that transmits a radio signal including acquired information to the outside, and the in-subject introduction device. An in-subject introduction system comprising a receiving device for receiving a wireless signal, wherein the in-subject introduction device outputs a signal including an information main component including the acquired in-subject information. And dummy component output means for outputting a dummy component formed by one or more alternating current signals having a predetermined frequency component, and at least a part of the gap portion where the information body portion does not exist in the signal including the information body portion A dummy insertion means for inserting the dummy component into the wireless communication means, and a wireless transmission means for wirelessly transmitting a signal including the information main body portion into which the dummy component is inserted to the outside. The receiving device includes a receiving antenna and an external device that receives a radio signal transmitted from the intra-subject introduction device via the receiving antenna and extracts the in-subject information from the received radio signal. It is characterized by that.

  The transmission device and the in-subject introduction system according to the present invention include dummy insertion means for inserting a dummy component formed by an AC signal with respect to a gap portion generated between information body components output from the information body output means. Compared to the case where the gap portion is composed of only the direct current component, the frequency band of the radio signal to be transmitted can be narrowed, and the average level difference between the information body component and the gap portion is reduced. It is possible to do this.

  Hereinafter, a transmitting apparatus and a system for introducing into a subject to which the transmitting apparatus as the best mode for carrying out the present invention (hereinafter simply referred to as an “embodiment”) is applied to the apparatus for introducing a subject will be described. Note that the drawings are schematic, and it should be noted that the relationship between the thickness and width of each part, the ratio of the thickness of each part, and the like are different from the actual ones. Of course, the part from which the relationship and ratio of a mutual dimension differ is contained. In the following, the embodiment will be described using an example in which the transmission apparatus is applied to an intra-subject introduction apparatus. However, the application field of the transmission apparatus is not necessarily limited to the intra-subject introduction apparatus. Needless to say.

(Embodiment 1)
First, the in-subject introduction system according to the first embodiment will be described. FIG. 1 is a schematic diagram illustrating an overall configuration of the in-subject introduction system according to the first embodiment. As illustrated in FIG. 1, the in-subject introduction system according to the first embodiment includes a capsule endoscope 2 that is introduced into the subject 1 and functions as an example of a transmission device and an in-subject introduction device. A receiving device 3 for receiving a radio signal transmitted from the capsule endoscope 2, and a display for displaying the contents of the radio signal transmitted from the capsule endoscope 2 received by the receiving device 3. A device 4 and a portable recording medium 5 for transferring information between the receiving device 3 and the display device 4 are provided.

  The display device 4 is for displaying an in-vivo image captured by the capsule endoscope 2 received by the receiving device 3, and displays an image based on data obtained by the portable recording medium 5. It has a configuration such as a workstation that performs. Specifically, the display device 4 may be configured to directly display an image by a CRT display, a liquid crystal display, or the like, or may be configured to output an image to another medium such as a printer.

  The portable recording medium 5 is detachable from an external device 8 and a display device 4 to be described later, and has a structure capable of outputting and recording information when attached to both. Specifically, the portable recording medium 5 is attached to the external device 8 while the capsule endoscope 2 is moving in the body cavity of the subject 1, and information on the position of the capsule endoscope 2 is displayed. Record. Then, after the capsule endoscope 2 is ejected from the subject 1, the capsule endoscope 2 is taken out from the external device 8 and attached to the display device 4, and the recorded data is read out by the display device 4. When data is transferred between the external device 8 and the display device 4 by a portable recording medium 5 such as a compact flash (registered trademark) memory, and the external device 8 and the display device 4 are connected by wire. Unlike the capsule endoscope 2, the subject 1 can behave freely even when the capsule endoscope 2 is moving inside the subject 1.

  Next, the receiving device 3 will be described. FIG. 2 is a schematic block diagram showing the overall configuration of the receiving device 3. First, as shown in FIGS. 1 and 2, the receiving device 3 is received via the receiving antennas 7 a to 7 h for receiving the radio signals transmitted from the capsule endoscope 2 and the receiving antennas 7 a to 7 h. And an external device 8 that performs predetermined processing on the wireless signal.

  The receiving antennas 7 a to 7 h are for receiving radio signals transmitted from the capsule endoscope 2. Specifically, the receiving antennas 7 a to 7 h have a configuration including, for example, a loop antenna and a fixing unit for fixing the loop antenna on the body surface of the subject 1. In the first embodiment, the capsule endoscope 2 that is a radio signal transmission source is introduced into the subject 1 and transmits a radio signal while moving inside the subject 1. ˜7h is selected based on the control of the external device 8 and the radio signal reception condition that is most excellent according to the position of the capsule endoscope 2 is selected, for example, the radio signal having the maximum reception intensity is selected. The radio signal is received via the receiving antenna 7. In the example shown in FIG. 1, the number of reception antennas 7 is eight. However, the number of reception antennas 7 is not limited to the number, and an arbitrary number of reception antennas 7 may be used.

  The external device 8 is for performing predetermined reception processing on a radio signal received via any of the reception antennas 7a to 7h. Specifically, as shown in FIG. 2, the external device 8 is received via a changeover switch 10 that switches a reception antenna 7 used when receiving a radio signal, and a reception antenna 7 selected by the changeover switch 10. A reception circuit 11 that performs reception processing such as demodulation on the received radio signal, a frequency filter 12 that filters a signal output from the reception circuit, and a DC (direct current) component of the filtered signal by AC coupling. An AC coupling circuit 13 that performs reproduction, a signal processing circuit 14 that performs predetermined processing on the image signal S1 output from the AC coupling circuit 13, and an image that is input via the signal processing circuit 14 together with overall control. The control part 15 which performs output control of signal S1 and the memory | storage part 16 which memorize | stores image signal S1 based on control of the control part 15 are provided. The storage unit 16 has a function of storing the image signal S1 in the portable recording medium 5 shown in FIG.

  The external device 8 has a mechanism for selecting an antenna suitable for receiving a radio signal from the reception antennas 7a to 7h. Specifically, the external device 8 is a sample-and-hold circuit 17 that samples and holds a received intensity signal S2 that indicates the intensity of a radio signal received via the receiving antenna 7, and an analog signal that is output from the sample-and-hold circuit 17. And an A / D converter 18 for converting the received intensity signal S2 into a digital signal. Further, in the control unit 15, a selection control unit 15a that performs a control operation at the time of antenna selection is provided.

  The antenna selection operation will be briefly described. First, the received intensity signal S2 output from the receiving circuit 11 is sampled and held by the sample and hold circuit 17 and converted into a digital signal by the A / D conversion unit 18 and then input to the selection control unit 15a. The input operation of the reception strength signal S2 to the selection control unit 15a is performed for each of the reception antennas 7a to 7h, and the selection control unit 15a selects the reception antenna 7 having the maximum reception strength signal S2 and switches the selection result. Output to the switch 10. The change-over switch 10 selects the receiving antenna 7 based on the output of the selection control unit 15a, and thereafter receives a radio signal including an image signal.

  The external device 8 includes a power supply unit 19 for supplying driving power to each of the above components. The external device 8 is configured by the above components.

  Next, the capsule endoscope 2 will be described. In the first embodiment, the capsule endoscope 2 functions as a transmitting device and an in-subject introduction device in the scope of claims, and is introduced into the subject 1 so as to be inside the subject. While acquiring information, it has the function to transmit a radio signal to the receiver 3.

  FIG. 3 is a block diagram showing a schematic configuration of the capsule endoscope 2. As shown in FIG. 3, the capsule endoscope 2 wirelessly transmits the in-subject information acquisition unit 21 for acquiring in-subject information and the acquired in-subject information to the receiving device 3. A wireless transmission unit 25. The capsule endoscope 2 is formed by an AC signal and a signal processing unit 22 that performs a predetermined process on the in-subject information output from the in-subject information acquisition unit 21 and outputs an information main body portion. A dummy component output unit 23 that generates and outputs the dummy component to be output, and an adder unit 24 that combines the output information main body portion and the dummy component that are respectively output to the wireless transmission unit 25. In addition, the capsule endoscope 2 includes a timing generator 26 for synchronizing the driving timing of each of the above-described components, and a battery 27 for supplying driving power for each of the components.

  The in-subject information acquisition unit 21 is for acquiring in-subject information when the capsule endoscope 2 is introduced into the subject 1. In the first embodiment, an in-subject image is acquired as in-subject information, and the in-subject information acquisition unit 21 has a configuration including an imaging mechanism for acquiring an image. Specifically, the in-subject information acquisition unit 21 is an LED that functions as an illumination unit, an LED drive circuit 29 that controls driving of the LED 28, and an imaging unit that captures an image of at least a part of the area illuminated by the LED 28. A functioning CCD 30 and a CCD driving circuit 31 for controlling the driving of the CCD 30 are provided. In the first embodiment, the CCD is used as the image pickup unit. However, such a configuration is not essential, and the image pickup unit may be formed of, for example, a CMOS.

  The wireless transmission unit 25 is for wirelessly transmitting information input via the addition unit 24 to the outside. Specifically, the wireless transmission unit 25 includes a transmission circuit 32 that performs necessary modulation processing on input information and a transmission antenna 33.

  The signal processing unit 22 is for generating an image signal by performing predetermined processing on the image information acquired by the CCD 30, and functions as an information body output unit in the claims. In the first embodiment, the image signal output by the signal processing unit 22 functions as an information body portion in the claims. That is, the image signal has the configuration shown in FIG. 4, and the signal processing unit 22 captures image information captured by the CCD 30 in the image signal period TM constituting one frame period (frame period) corresponding to one image. The signal component corresponding to each scanning line is output. Specifically, as shown in FIG. 4, the number of image line periods TH corresponding to the number of scanning lines is provided in the image signal period TM, and the signal processing unit 22 performs image processing for each of the image line periods TH. An information body component S corresponding to each scanning line of information is generated and output. Here, a horizontal blanking period Th is provided between the adjacent image line periods TH, and the image signal output from the signal processing unit 22 includes any signal component in the horizontal blanking period Th. Suppose that it is not possible.

  As shown in FIG. 4, a synchronization period for performing a synchronization operation is provided in the first half of one frame period, and the signal processing unit 22 generates and outputs a synchronization signal corresponding to the synchronization period TS. Has the function to perform. The synchronization signal is composed of information components necessary for the synchronization operation when image data is extracted from the radio signal received on the receiving device side. In the first embodiment, the synchronization signal is also treated as an example of the information body component S. I will do it.

  The dummy component output unit 23 is for generating and outputting a dummy component composed of an AC signal having a predetermined frequency in accordance with a predetermined timing, and as shown in FIG. 4, a dummy component corresponding to the horizontal blanking period Th. It has a function of outputting P. For example, the dummy component output unit 23 is provided with a counter that is synchronized with the horizontal synchronization signal and the vertical synchronization signal in advance, and has a function of generating and outputting the dummy component P using the counter value of this counter as a reference.

  The dummy component generated and output by the dummy component output unit 23 is for alleviating a problem that occurs during processing in the receiving device 3. FIG. 5 is a schematic diagram illustrating an example of the configuration of the dummy component. As shown in FIG. 5, the dummy component generated and output by the dummy component output unit 23 can be realized by, for example, a pulse signal generated according to a single frequency.

  Note that the average level and the average frequency of the dummy component P generated and output by the dummy component output unit 23 may be arbitrary. However, as a more preferable form, regarding the average level of the dummy component P, the average level of the information main body component S positioned in the previous stage and the average level of the information main body component S positioned in the subsequent stage are different for each of the dummy components P. Is a value between the two, for example, an average value. Further, the average frequency of the dummy component P is a value between the two when the frequency of the information main body component S at the previous stage and the frequency of the information main body component S at the subsequent stage are different, for example, when they match. Is approximately equal to both. In the example of FIG. 5, a pulse signal whose average level and frequency of the dummy component P coincides with the value of the information body component S is used on the assumption that the average level and frequency of each information body component S do not vary. It is said.

  The adder 24 functions as an example of dummy data insertion means in the claims. Specifically, the adding unit 24 has a function of combining the information main body component output from the signal processing unit 22 and the dummy component output from the dummy component output unit 23, and transmits the combined signal to the transmission circuit 32. It has the function to output to.

  FIG. 6 is a schematic diagram showing the contents of the signal output from the adder 24. As shown in FIG. 5, the signal output from the adder 24 has a dummy component P inserted in the gap between the information body portions S constituting the image signal, and the gap is eliminated as a whole signal. It has become. Such a signal is output from the adder 24 to the transmission circuit 32, and the transmission circuit 32 performs processing such as modulation on the signal shown in FIG. 6 and performs wireless transmission to the reception device 3 via the transmission antenna 33. Will be.

  The receiving device 3 receives a radio signal transmitted from the capsule endoscope 2 via the selected receiving antenna 7. The received radio signal is subjected to processing such as demodulation by the receiving circuit 11 provided in the external device 8, and then the noise component is removed by the frequency filter 12 and the DC component is reproduced by the AC coupling circuit 13. Is input to the signal processing circuit 14. The signal processing circuit 14 performs predetermined processing and outputs an image signal S1 to the storage unit 16 via the control unit 15, and the storage unit 16 stores the contents of the image signal S1 in the portable recording medium 5. .

  Next, advantages of the in-subject introduction system according to the first embodiment will be described. As described above, in the intra-subject introduction system according to the first embodiment, a dummy component is inserted into a portion corresponding to the horizontal blanking period with respect to a radio signal transmitted from the capsule endoscope 2 serving as a transmission device. Things are going to be used. By adopting such a configuration, in the intra-subject introduction system according to the first embodiment, it is possible to reduce the burden on the receiving device side and effectively remove noise components in the processing of radio signals. Has the advantage.

  That is, by inserting a dummy component that is an AC signal into a portion corresponding to the horizontal blanking period, the radio signal transmitted from the capsule endoscope 2 corresponds to the portion corresponding to the image line period and the horizontal blanking period. It is possible to prevent a sudden voltage level change from occurring at the boundary with the portion. Therefore, when the capsule endoscope 2 achieves uniform average levels using AC coupling in the AC coupling circuit 13 provided in the external device 8, there is no adverse effect caused by the instantaneous voltage change. There is an advantage that it is possible to transmit a radio signal with reduced burden on the apparatus side.

  From the viewpoint of enjoying such an advantage, any dummy component inserted by the gap portion can be used as long as it is formed by a predetermined AC signal. That is, it is possible to suppress fluctuations in the average level by inserting an AC signal as a dummy component, as compared with a conventional case where a DC component corresponding to only High or Low is used. It is. However, as described above, as described above, as described above, the dummy component is set to an average level that is approximately equal to and ideally equal to the average level of the information body portion. In such a case, an instantaneous voltage such as a sag is used. Since the change can be almost eliminated, the burden on the AC coupling circuit 13 can be further reduced.

  In the first embodiment, it is possible to prevent a low-frequency component from being included in a radio signal transmitted from the capsule endoscope 2 by inserting a dummy component that is an AC signal in the horizontal blanking period. Have advantages. That is, in the case of a gap portion that is configured with only a DC component of a constant voltage corresponding to High or Low in the conventional configuration, a low-frequency component corresponding to the time length of the gap period such as a horizontal blanking period is a radio signal. Inevitably included, causing problems such as expanding the pass frequency band of the frequency filter 12 on the receiving device 3 side. On the other hand, in the first embodiment, since a dummy component formed by an AC signal is inserted into the gap portion, a low frequency component corresponding to the length of the gap period is generated with respect to the transmitted radio signal. In addition, it is possible to transmit a radio signal having a narrower frequency bandwidth than in the past.

  For this reason, in the receiving device 3 that receives a radio signal, it is possible to narrow the pass frequency band of the frequency filter 12 provided therein, as compared with the prior art, and by removing the noise component by narrowing the pass frequency band. It has the advantage that it can be performed efficiently.

  Further, in the first embodiment, as an AC signal constituting the dummy component, an AC signal composed of a single clock is used as shown in FIG. When such a configuration is adopted, the mechanism of the dummy component output unit 23 can be simplified, and, for example, a filtering mechanism that extracts only the frequency component corresponding to the frequency of the single clock shown in FIG. In the first embodiment, the horizontal blanking period can be easily determined.

  Of course, an AC signal other than that shown in FIG. 5 may be used as the AC signal constituting the dummy component. For example, a simulated noise (PN) code may be used instead of the single clock shown in FIG. A simulated noise code is a general term for a spread code sequence used for spread spectrum. When a dummy component is formed using such a code sequence, the dummy component is constituted by an AC signal having a wide frequency band. It will be. Thus, even when the simulated noise code is used, it is possible to enjoy the above-described advantages by configuring the average frequency and the average level to be equal to those of the information main body portion, for example. An advantage of using the simulated noise code is that the peak value of the modulation spectrum can be reduced and the spectrum can be dispersed when the transmission circuit 32 performs modulation processing.

(Embodiment 2)
Next, the in-subject introduction system according to the second embodiment will be described. In the intra-subject introduction system according to the second exemplary embodiment, the dummy component is inserted into the gap portion between the information body components by appropriately switching the signal output to the transmission circuit 32 instead of the addition unit 24. The structure provided with the part.

  FIG. 7 is a block diagram schematically showing the configuration of the capsule endoscope 35 provided in the in-subject introduction system according to the second embodiment. As illustrated in FIG. 7, the capsule endoscope 35 includes a switching unit 36 at the output destination of the signal processing unit 22 and the dummy component output unit 23. In the second embodiment, components having the same reference numerals and names as those of the first embodiment have the same configurations and functions as those of the first embodiment unless otherwise specified. Although not shown, also in the second embodiment, the in-subject introduction system includes the receiving device 3, the display device 4, and the portable recording medium 5 as in the first embodiment.

  The switching unit 36 has a function of outputting any one of the signal components output from the signal processing unit 22 and the dummy component output unit 23 to the transmission circuit 32 according to a predetermined timing. Specifically, the switching unit 36 transmits the information body component output from the signal processing unit 22 during the synchronization period and the image line period within the image signal period according to the operation clock supplied from the timing generation unit 26. The dummy component output from the dummy component output unit 23 is output to the transmission circuit 32 during the horizontal blanking period.

  Such an operation means that a dummy component is inserted into a gap between adjacent information body components when the information body component output from the signal processing unit 22 is mainly considered. In this sense, the switching unit 36 according to the second embodiment functions as an example of a dummy component insertion unit in the claims. Therefore, even when the switching unit 36 is used instead of the adding unit 24, it is possible to receive the same advantages as those in the first embodiment.

  When the switching unit 36 inserts a dummy component into the information main body component as in the second embodiment, the insertion timing is controlled by the switching unit 36. Therefore, the dummy component output unit 23 may be configured to always generate and output a dummy component in addition to the horizontal blanking period. However, in the example of the second embodiment, dummy components are generated / output only during the horizontal blanking period as in the first embodiment, from the viewpoint of preventing an increase in power consumption required for generating / outputting dummy components. It is said.

(Embodiment 3)
Next, an in-subject introduction system according to the third embodiment will be described. In the third embodiment, as the physical structure of the capsule endoscope, the in-subject information acquisition unit and the dummy component output unit are formed on different substrates.

  FIG. 8 is a diagram schematically illustrating a structure of a capsule endoscope provided in the in-subject introduction system according to the third embodiment. As shown in FIG. 8, in the third embodiment, the in-subject information acquisition unit 21, the timing generation unit 26, and the signal processing unit 22 are formed on the information main body output board 38, and the dummy component output unit 23, The addition unit 24 and the wireless transmission unit 25 have a configuration formed on a dummy component insertion board 39 that is formed separately from the information body output board 38. Wirings 40 and 41 are arranged between the information main body output board 38 and the dummy component insertion board 39, and the components formed on the respective boards are electrically connected.

  The dummy component output unit 23 has a function of generating a dummy component independently of the information acquired by the in-subject information acquisition unit 21. Therefore, when the dummy component output unit 23 and the in-subject information acquisition unit 21 are formed on the same substrate, the dummy component output unit 23 is caused by the operation of the dummy component output unit 23 due to a parasitic capacitance generated between them. There is a possibility that a noise component is mixed in the image signal. In particular, since the in-subject information acquisition unit 21 performs the imaging operation of the next image even during the horizontal blanking period, the possibility of being affected by the operation of the dummy component output unit 23 is completely eliminated. I can't deny it.

  Therefore, in the third embodiment, by forming the in-subject information acquisition unit 21 and the dummy component output unit 23 on separate and independent substrates, one operation may affect the other operation. It has been reduced to a level that can be ignored. By adopting such a configuration, the in-subject introduction system according to the third embodiment can acquire the high-quality in-subject image in addition to the advantages in the first embodiment. Will have advantages.

  As mentioned above, although this invention was demonstrated using Embodiment 1-3, this invention should not be limited and limited to said embodiment, If it is those skilled in the art, it will be various examples, a modification, etc. It is possible to conceive. For example, in the first to third embodiments, the dummy component is inserted into the gap portion corresponding to the horizontal blanking period, but it goes without saying that the dummy component may be inserted into the other gap portion that occurs. is there. That is, the present invention can achieve the effect by inserting a dummy component into every gap portion that can be generated between the information body portions output from the information body output means. It may be other than the one corresponding to the blanking period. Further, it is not necessary to insert dummy components for all the gap portions, and a configuration may be adopted in which dummy components are inserted for only a part of the gap portions.

  In the first to third embodiments, the information about the in-subject image acquired by the in-subject information acquisition unit 21 is used as the information included in the information main body. However, it is necessary to limit the information to the information. It is also possible to use something other than image information. Further, the transmission device to which the present invention is applied need not be limited to the capsule endoscope as the intra-subject introduction device.

1 is a schematic diagram illustrating an overall configuration of an in-subject introduction system according to a first embodiment. It is a block diagram which shows the structure of the receiver with which the in-subject introduction system is equipped. It is a block diagram which shows the structure of the capsule endoscope with which an in-subject introduction system is equipped. 4 is a time chart illustrating information main body components output from a signal processing unit and dummy components output from a dummy component output unit. It is a schematic diagram which shows the specific structure of a dummy component. It is a schematic diagram which shows the structure of the signal component output from the addition part. FIG. 6 is a block diagram illustrating a configuration of a capsule endoscope provided in an in-subject introduction system according to a second embodiment. FIG. 6 is a block diagram illustrating a configuration of a capsule endoscope provided in an in-subject introduction system according to a third embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Subject 2 Capsule endoscope 3 Receiving apparatus 4 Display apparatus 5 Portable recording medium 7a-7h Reception antenna 8 External apparatus 10 Changeover switch 11 Reception circuit 12 Frequency filter 13 AC coupling circuit 14 Signal processing circuit 15 Control part 15a selection Control unit 16 Storage unit 17 Sample hold circuit 18 A / D conversion unit 19 Power supply unit 21 In-subject information acquisition unit 22 Signal processing unit 23 Dummy component output unit 24 Addition unit 25 Wireless transmission unit 26 Timing generation unit 27 Battery 28 LED
29 LED drive circuit 30 CCD
31 CCD drive circuit 32 Transmitter circuit 33 Transmitting antenna 35 Capsule endoscope 36 Switching unit 38 Information body output board 39 Dummy component insertion board 40, 41 Wiring

Claims (11)

A transmission device for transmitting a radio signal including at least an information body part to the outside,
Information body output means for outputting a signal including the information body portion;
Dummy component output means for outputting a dummy component formed by one or more AC signals having a predetermined frequency component;
Dummy inserting means for inserting the dummy component into at least a part of a gap portion where the information main body portion does not exist in the signal including the information main body portion;
Wireless transmission means for wirelessly transmitting a signal including the information main body portion into which the dummy component is inserted, to the outside;
A transmission device comprising:   2. The transmission apparatus according to claim 1, wherein the dummy component is formed by an AC signal having an average level substantially matching an average level of a signal including the information main body portion.   The transmission apparatus according to claim 1, wherein the dummy component is formed by an AC signal having an average frequency substantially coincident with an average frequency of a signal including the information main body portion.   The transmission apparatus according to claim 1, wherein the dummy component is formed by a predetermined fixed pattern.   The transmission apparatus according to claim 1, wherein the dummy component is formed by a clock signal having a constant frequency.   The transmission apparatus according to claim 1, wherein the dummy component is formed using a pseudo noise code.   The dummy inserting means comprises an adding means for synthesizing the information body portion of the signal output from the information body output means and the dummy component output from the dummy component output means. Item 7. The transmission device according to any one of Items 1 to 6.   The dummy insertion means includes switching means for switching a signal component output to the wireless transmission means between the information main body portion and the dummy component based on a predetermined timing. Item 7. The transmission device according to any one of Items 1 to 6.   The transmission device according to claim 1, wherein the signal including the information main body portion is an image signal, and the gap portion is a horizontal blanking period. The transmission device has a function of being introduced into a subject and acquiring in-subject information,
The transmission apparatus according to claim 1, wherein the information main body generation part is formed including the in-subject information. A subject comprising an intra-subject introduction device that transmits a radio signal including information acquired and introduced into the subject to the outside, and a reception device that receives a radio signal transmitted from the intra-subject introduction device. An internal introduction system,
The in-subject introduction device comprises:
An information body output means for outputting a signal including an information body component including the acquired in-subject information;
Dummy component output means for outputting a dummy component formed by one or more AC signals having a predetermined frequency component;
A dummy inserting means for inserting the dummy component into at least a part of a gap portion where the information main body portion does not exist in the signal including the information main body portion;
Wireless transmission means for wirelessly transmitting a signal including the information main body portion into which the dummy component is inserted, to the outside;
With
The receiving device is:
A receiving antenna;
An external device that receives a radio signal transmitted from the in-subject introduction device via the reception antenna and extracts the in-subject information from the received radio signal;
An in-subject introduction system characterized by comprising:

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