JP2007124142A - Receiver apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect a disconnection of a feeding line in a short time and with reliability by use of a simple structure. <P>SOLUTION: A receiver apparatus 2 uses a switch 20 for selectively switching coaxial cables 9a-9d connected to reception antennas 8a-8d to receive, via a selected coaxial cable and its associated reception antenna, image information transmitted from a capsule endoscope 3. The receiver apparatus 2 has a switch 22, a grounding means, a disconnection detecting circuit 23, and a control unit 26. The switch 22 branches the coaxial cables near the switch 20 and selectively switches the branched coaxial cables. The grounding means is arranged between the coaxial cables and the reception antennas so as to ground the coaxial cables. The disconnection detecting circuit 23 applies, via a constant current source 203, a DC voltage to the coaxial cable selected by the switch 22 to determine whether the coaxial cable has been disconnected, depending on whether the voltage of the coaxial cable has been grounded. The control unit 26 controls the selective switching of the switch 22, and also controls the disconnection detection of the disconnection detecting circuit 23 in synchronism with the selective switching control. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention selectively switches a plurality of feed lines respectively connected to a plurality of reception antennas by a selection switching unit, and transmits transmission information transmitted from a moving transmission apparatus via the selection-switched feed lines and reception antennas. The present invention relates to a receiving device for receiving.

  In recent years, swallowable capsule endoscopes have appeared in the field of endoscopes. This capsule endoscope is provided with an imaging function and a wireless communication function. Capsule endoscopes are peristaltic in the body cavity, for example, the stomach, small intestine, etc., after being swallowed from the patient's mouth for observation (examination) and before being spontaneously discharged from the human body. It has the function to move according to and to image sequentially.

  While moving inside the body cavity, image information imaged inside the body by the capsule endoscope is sequentially transmitted to the outside by radio signals and stored in a memory provided in an external receiving device. When the patient carries the receiving device having the receiving function and the memory function, the patient can freely act after swallowing the capsule endoscope until the capsule endoscope is discharged. Thereafter, the doctor or nurse can make a diagnosis by displaying an image of the organ on the display based on the image data stored in the memory.

  In general, a receiving apparatus disperses and arranges a plurality of receiving antennas that receive radio signals transmitted from a capsule endoscope, and selectively switches and receives one receiving antenna with few radio signal reception errors. (See Patent Document 1).

Japanese Patent Laid-Open No. 2003-19111

  By the way, a plurality of receiving antennas of the above-described receiving apparatus are connected to one receiving apparatus main body by a coaxial cable at each part outside the subject body, and are repeatedly mounted every time an inspection is performed. It becomes easy to break the cable.

  For this reason, the disconnection check of the coaxial cable or the like is performed before the inspection, but this disconnection check requires a work such as confirming the reception state by bringing a dummy transmitter close to each receiving antenna. There was a problem that it took time.

  The present invention has been made in view of the above, and an object of the present invention is to provide a receiving apparatus that can detect a disconnection of a feeder line in a short time and with a simple configuration.

  In order to achieve the above object, a receiving apparatus according to claim 1 selects and switches a plurality of feed lines respectively connected to a plurality of receive antennas by using a selection switching means, and selects the feed line and the receive antenna that are selected and switched. In the receiving device that receives the transmission information transmitted from the moving transmitting device, the plurality of feed lines are branched in the vicinity of the selection switching means, and the selection switching for detection is performed to selectively switch each of the branched feed lines. A DC voltage to the power supply line provided between the power supply line, the grounding means for grounding the power supply line, and the selection switching means for detection via a constant current source. A disconnection detecting means for detecting the presence or absence of disconnection of the power supply line depending on whether or not the voltage of the power supply line is a ground voltage; In synchronization with the selection switching control, characterized by comprising a control means for causing disconnection detection by said disconnection detection means.

  According to a second aspect of the present invention, in the above invention, the receiving antenna is an open type receiving antenna, and the feeder line and the receiving antenna are connected by a transformer type balun, and the transformer type balun. The power supply line side of is grounded.

  According to a third aspect of the present invention, in the above-described invention, the receiving antenna is an open type receiving antenna, and the feed line and the receiving antenna are connected by a short-circuit element, and one end of the short-circuit element is provided. Is grounded.

  The receiving device according to claim 4 is characterized in that, in the above invention, the receiving antenna is a loop antenna, and one end where the feed line and the receiving antenna are connected is grounded. To do.

  According to a fifth aspect of the present invention, in the above invention, the feeder is a coaxial cable, and the outer conductor is grounded.

  According to a sixth aspect of the present invention, in the above invention, the control unit performs control to output a disconnection detection result.

  According to the receiving device of the present invention, the plurality of feeder lines are respectively branched in the vicinity of the selection switching means for selectively switching the plurality of feeder lines respectively connected to the plurality of receiving antennas. A detection selection switching means for selecting and switching is provided, a grounding means for grounding the power supply line is provided between the power supply line and the receiving antenna, and the power supply line selectively switched by the detection selection switching means is provided. A disconnection detecting means for applying a direct current voltage and detecting the presence or absence of disconnection of the power supply line depending on whether or not the voltage of the power supply line is a ground voltage; Since disconnection detection by the disconnection detection means is performed in synchronization with this selection switching control, it is possible to detect the disconnection of the feeder line in a short time and with a simple configuration. The effect say.

  Exemplary embodiments of a receiving apparatus according to the present invention will be explained below in detail with reference to the accompanying drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a schematic configuration of a capsule endoscope inspection system using a receiving device 2 according to a first embodiment of the present invention. As shown in FIG. 1, when the capsule endoscope 3 is introduced into the subject 1, the capsule endoscope 3 moves inside the subject 1, images the inside of the subject, and uses the captured image signal as a radio signal. Transmit to the outside of the subject 1.

  The receiving device 2 includes a plurality of receiving antennas 8a to 8d that are distributed outside the body of the subject 1, coaxial cables 9a to 9d that are connected to the receiving antennas 8a to 8d, and radio that is connected to the coaxial cables 9a to 9d. It has a unit 2a and a receiving body unit 2b connected to the wireless unit 2a.

  The image signals transmitted from the capsule endoscope 3 are received by the plurality of reception antennas 8a to 8d, and the image signals are taken into the reception main body unit 2b via the wireless unit 2a. The reception main unit 2b selects and receives the reception antenna having the highest reception intensity from among the plurality of reception antennas 8a to 8d, sequentially receives the image signals received by this selection, and the capsule endoscope 3 is covered. A series of images until the sample 1 is discharged is stored.

  After the capsule endoscope 3 is ejected from the subject 1, the portable recording medium 5 is detached from the receiver body unit 2b and attached to the display device 4. The display device 4 reads a series of images stored in the portable recording medium 5 and performs display processing.

  FIG. 2 is a block diagram illustrating a configuration of the receiving device 2. As shown in FIG. 2, the wireless unit 2 a is connected to the changeover switches 20 and 22 that connect the reception antennas 8 a to 8 d, the reception circuit 21 that receives the reception signal from the changeover switch 20, and the changeover switch 22. And a disconnection detection circuit 23.

  When the changeover signal S3 is input, the changeover switch 20 selects one coaxial cable indicated by the changeover signal S3 from the coaxial cables 9a to 9d, and the reception circuit 21 selects the coaxial cable selected by the changeover switch 20. An image signal is received via a cable, and a baseband signal S1 including the image signal and a received intensity signal S2 indicating a received electric field intensity of the image signal are output to the receiving body unit 2b side.

  On the other hand, when the switching signal S4 instructing switching of the coaxial cable similar to the switching signal S3 is input, the selector switch 22 selects the coaxial cable instructed by the switching signal S4 from the coaxial cables 9a to 9d. The selected coaxial cable is connected to the disconnection detection circuit 23. When the control signal S5 instructing the detection of the disconnection is input, the disconnection detection circuit 23 performs a disconnection check on the coaxial cable that is selected and connected, and outputs the result of the disconnection check to the reception body unit 2b as the detection signal S6. To do.

  The reception main unit 2b includes a signal processing circuit 24, an A / D conversion unit 25, a control unit 26 having a switching control unit 260, a display unit 27, a storage unit 28, and a removable portable recording medium 5. And a power supply unit 29. The power supply unit 29 supplies power to each unit described above.

  The signal processing circuit 24 generates an image signal from the baseband signal S <b> 1 input from the receiving circuit 21 and outputs the image signal to the control unit 26. The A / D conversion unit 25 performs A / D conversion on the reception intensity signal S2 input from the reception circuit 21, and outputs it to the control unit 26 as a digital signal indicating the reception electric field intensity.

  The control unit 26 records the image signal input from the signal processing circuit 24 on the portable recording medium 5 and performs processing control to display and output an image on the display unit 27 as necessary. Further, the switching control unit 260 selects a reception antenna having the maximum reception intensity based on the digital signal indicating the reception electric field intensity input from the A / D conversion unit 25, and a coaxial cable for connecting the reception antenna. A switching signal S3 instructing switching to is output to the changeover switch 20. In addition, the switching control unit 260 sends a switching signal S4 instructing switching of the coaxial cable for the disconnection check to the selector switch 22, and the control signal S5 instructing disconnection checking is disconnected corresponding to the switching signal S4. Output to the detection circuit 23 to obtain the detection signal S6.

  FIG. 3 is a block diagram showing a specific connection relationship between the receiving antenna 8a and the coaxial cable 9a. As shown in FIG. 3, the receiving antenna 8a is an open antenna, and the coaxial cable 9a has a core wire 90a that is an inner conductor and an outer conductor 90A.

  The receiving antenna 8a and the coaxial cable 9a are connected by a transformer type balun 10. Coils are formed respectively on the coaxial cable 9a side of the reception antenna 8a and the reception antenna 8a side of the coaxial cable 9a. The reception antenna 8a and the coaxial cable 9a are electromagnetically coupled to each other, and the reception antenna 8a that is a balanced line The leakage current generated by the connection with the coaxial cable 9a which is an unbalanced line is reduced. The coil on the coaxial cable 9a side is formed at the tip of the core wire 90a and grounded together with the external conductor 90A.

FIG. 4 is a block diagram showing a configuration centered on the disconnection detection circuit 23. As shown in FIG. 4, the disconnection detection circuit 23 includes a comparator 202 that compares an input voltage with a threshold voltage Vref and outputs the result as a detection signal S6. The threshold voltage Vref is input to one input terminal of the comparator 20, and the core wire 90a is connected to the other input terminal. A DC power source 200 that outputs a DC voltage V _IN is connected to the core wire 90a via a switch 201 and a constant current source 203. The switch 201 is opened and closed by a control signal S5. Note that the voltage V _IN is equal to or higher than the threshold voltage Vref. A resistor may be used instead of the constant current source 203.

When the core wire 90a of the coaxial cable 9a is not broken, the voltage V _IN is applied to the core wire 90a by the “closed” of the switch 201 and is grounded via the transformer type balun 10. Therefore, between the core wire 90a and the ground The voltage is a ground voltage, and the voltage input to the other input terminal of the comparator 202 is equal to or lower than the threshold voltage Vref. As a result, the comparator 202 outputs a detection signal S5 indicating that the voltage input from the other input terminal is equal to or lower than the threshold voltage Vref, and the control unit 26 determines that there is no disconnection.

On the other hand, when the core wire 90a of the coaxial cable 9a is broken, as shown in FIG. 5, by closing the switch 201, the voltage _VIN is applied to the core wire 90a via the constant current source 203 and directly grounded. Therefore, the voltage V _IN is applied to the other input terminal of the comparator 202 as it is. The comparator 202 outputs a detection signal S6 indicating that the voltage (voltage V _IN ) input from the other input terminal is equal to or higher than the threshold voltage Vref, and the control unit 26 determines that the circuit is disconnected.

  The control unit 26 outputs the switching signal S4, selects the next coaxial cable 9b, performs a disconnection check on the selected next coaxial cable 9b using the disconnection detection circuit 23, and similarly performs the same operation on all the coaxial cables. A disconnection check is executed for 9a to 9d. As a result, the control unit 26 can immediately determine whether or not the coaxial cables 9a to 9d are disconnected and identify the coaxial cable that has been disconnected.

  When the control unit 26 detects a disconnected coaxial cable, the control unit 26 may add a number to the coaxial cable in advance and display the number of the disconnected coaxial cable on the display unit 27. If no disconnection is detected, a message indicating that there is no disconnection may be displayed on the display unit 27.

  The switching control unit 260 of the control unit 26 described above may make the switching signals S3 and S4 the same signal and detect disconnection of the switched coaxial cable when the image signal is being received. Alternatively, the coaxial cables to which the switching signals S3 and S4 are instructed to switch may be made different so that disconnection detection is performed on the coaxial cable that has not received the image signal. Alternatively, the switching between the changeover switches 20 and 22 may be separated in time, and disconnection detection may be performed in a gap where reception processing is not performed. Furthermore, disconnection detection may be performed when the receiving apparatus 2 is not performing reception processing, such as before or after inspection. Furthermore, when a disconnection is detected during reception, the control unit 26 may perform control so as not to switch to the reception antenna connected to the disconnected coaxial cable.

  In the first embodiment, the coaxial cables 9a to 9d are branched, and a DC voltage can be applied to the branched coaxial cable to easily detect the presence or absence of disconnection, and the disconnected coaxial cable can be quickly identified. .

  In the first embodiment, the four coaxial cables 9a to 9d are shown and described. However, the number is not limited to this. In addition, when the coaxial cable is in poor contact, the result of the disconnection check may differ every time the disconnection check is performed. The control unit 26 stores the result of the disconnection check of each coaxial cable in the storage unit 28 so that the contact failure can be dealt with, and when the disconnection is detected a predetermined number of times, a warning display that prompts replacement is displayed on the display unit 27. You may make it do.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. In the first embodiment described above, the transformer type balun 10 is used to ground the core wire 90a of the coaxial cable 9a to detect disconnection. In the second embodiment, however, the short-circuit element realized by a diode or the like is used. Is used to detect the disconnection by grounding the core wire of the coaxial cable.

  FIG. 6 is a diagram showing a connection relationship between the receiving antenna 81a corresponding to the receiving antenna 8a shown in FIG. 5 and the coaxial cable 91a corresponding to the coaxial cable 90A shown in FIG. As shown in FIG. 6, one end of the open receiving antenna 81a is connected to the core wire 91a, and the other end is connected to the grounded external conductor 91A. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same components.

  In the connection portion between the receiving antenna 81a and the coaxial cable 91A, the core wire 91a and the external conductor 91A are connected by the short-circuit element 10A, and the short-circuit element 10A is grounded to allow direct current conduction from the core wire 91a to the external conductor 91A. ing.

When the core wire 91a of the coaxial cable 9a is not broken, the voltage V _IN is applied to the core wire 91a via the constant current source 203 and grounded via the short-circuit element 10A by “closing” the switch 201. The voltage between the first input terminal and the ground terminal is a ground voltage, and the voltage input to the other input terminal of the comparator 202 is equal to or lower than the threshold voltage Vref. As a result, the comparator 202 outputs a detection signal S5 indicating that the voltage input from the other input terminal is equal to or lower than the threshold voltage Vref, and the control unit 26 determines that there is no disconnection.

On the other hand, when the core wire 91a of the coaxial cable 9a is disconnected, the voltage V _IN is not applied directly to the core wire 91a via the constant current source 203 by “closing” the switch 201, and the comparator 91 is not directly grounded. This voltage V _IN is applied to the other input terminal of 202 as it is. The comparator 202 outputs a detection signal S5 indicating that the voltage (voltage V _IN ) input from the other input terminal is equal to or higher than the threshold voltage Vref, and the control unit 26 determines that the circuit is disconnected.

  The control unit 26 outputs the switching signal S4, selects the next coaxial cable 9b, performs a disconnection check on the selected next coaxial cable 9b using the disconnection detection circuit 23, and similarly performs the same operation on all the coaxial cables. A disconnection check is executed for 9a to 9d. As a result, the control unit 26 can immediately determine whether or not the coaxial cables 9a to 9d are disconnected and identify the coaxial cable that has been disconnected.

(Embodiment 3)
Next, a third embodiment of the present invention will be described. In the first and second embodiments described above, the receiving antennas 8a and 81a are both open-type, and the core wires 90a and 91a are grounded via the transformer-type balun 10 and the short-circuit element 10A, respectively. In the third aspect, the receiving antenna is a loop type, and the core wire is grounded via the loop type receiving antenna.

  FIG. 7 is a diagram illustrating a connection relationship between the receiving antenna 82a and the coaxial cable 92a. As shown in FIG. 7, one end of the loop-type receiving antenna 82a is connected to the core wire 92a of the coaxial cable 9a, and the other end is connected to the grounded external conductor 92A. Other configurations are the same as those of the first and second embodiments, and the same components are denoted by the same reference numerals.

When the core wire 92a of the coaxial cable 9a is not broken, the voltage V _IN is applied to the core wire 92a via the constant current source 203 and is grounded via the loop-type receiving antenna 82a when the switch 201 is closed. The voltage between the core 91a and the ground is the ground voltage, and the voltage input to the other input terminal of the comparator 202 is equal to or lower than the threshold voltage Vref. As a result, the comparator 202 outputs a detection signal S5 indicating that the voltage input from the other input terminal is equal to or lower than the threshold voltage Vref, and the control unit 26 determines that there is no disconnection.

On the other hand, when the core wire 92a of the coaxial cable 9a is disconnected, the voltage V _IN is not applied directly to the core wire 91a via the constant current source 203 by “closing” of the switch 201, and thus is not directly grounded. This voltage V _IN is applied to the other input terminal of 202 as it is. The comparator 202 outputs a detection signal S5 indicating that the voltage (voltage V _IN ) input from the other input terminal is equal to or higher than the threshold voltage Vref, and the control unit 26 determines that the circuit is disconnected.

  The control unit 26 outputs the switching signal S4, selects the next coaxial cable 9b, performs a disconnection check on the selected next coaxial cable 9b using the disconnection detection circuit 23, and similarly performs the same operation on all the coaxial cables. A disconnection check is executed for 9a to 9d. As a result, the control unit 26 can immediately determine whether or not the coaxial cables 9a to 9d are disconnected and identify the coaxial cable that has been disconnected.

1 is a block diagram showing a schematic configuration of a capsule endoscope system using a receiving apparatus according to a first embodiment of the present invention. It is a block diagram which shows schematic structure of the receiver concerning Embodiment 1 of this invention. It is a figure which shows the connection relation of the coaxial cable concerning Embodiment 1 of this invention, and a receiving antenna. It is a block diagram which shows schematic structure between a disconnection detection circuit and a receiving antenna in case there is no disconnection in a coaxial cable. It is a block diagram which shows the schematic structure between a disconnection detection circuit and a receiving antenna in case a coaxial cable has a disconnection. It is a figure which shows the connection relation of the coaxial cable concerning Embodiment 2 of this invention, and a receiving antenna. It is a figure which shows the connection relation of the coaxial cable and receiving antenna concerning Embodiment 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Subject 2 Reception apparatus 2a Wireless unit 2b Reception main body unit 3 Capsule endoscope 4 Display apparatus 5 Portable recording medium 8a-8d, 81a, 82a Reception antenna 9a-9d Coaxial cable 10 Trans | transformer balun 10A Short-circuit element 20, DESCRIPTION OF SYMBOLS 22 Changeover switch 21 Reception circuit 23 Disconnection detection circuit 24 Signal processing circuit 25 A / D conversion part 26 Control part 27 Display part 28 Memory | storage part 29 Electric power supply part 90a, 91a, 92a Core wire 90A, 91A, 92A External conductor 200 DC power supply 201 Switch 202 Comparator 203 Constant current source 260 Switching control unit

Claims (6)

A receiving device that selectively switches a plurality of feed lines respectively connected to a plurality of receiving antennas, and receives transmission information transmitted from a moving transmitting device via the selectively switched feeding lines and receiving antennas In
A selection switching means for detection for branching each of the plurality of power supply lines in the vicinity of the selection switching means and selectively switching each of the branched power supply lines;
A grounding means provided between the feed line and the receiving antenna for grounding the feed line;
Disconnection that detects the presence or absence of disconnection of the power supply line by applying a DC voltage to the power supply line selected and switched by the detection selection switching means via a constant current source and determining whether the voltage of the power supply line is a ground voltage or not. Detection means;
Selection switching control of the detection selection switching means and control means for performing disconnection detection by the disconnection detection means in synchronization with the selection switching control;
A receiving apparatus comprising:   The said receiving antenna is an open type receiving antenna, The said feeder and the said receiving antenna are connected by a transformer type balun, and the feeder line side of this transformer type balun is grounded. The receiving device described.   2. The reception according to claim 1, wherein the reception antenna is an open type reception antenna, and the feed line and the reception antenna are connected by a short-circuit element, and one end of the short-circuit element is grounded. apparatus.   The receiving apparatus according to claim 1, wherein the receiving antenna is a loop antenna, and one end where the feeding line and the receiving antenna are connected is grounded.   The receiving apparatus according to claim 1, wherein the feeder line is a coaxial cable, and an outer conductor is grounded.   The receiving apparatus according to claim 1, wherein the control unit performs control to output a disconnection detection result.

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