JP2014212468A - Video signal transmitter and video communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adjust a video signal output level of a transmitter on the basis of a light receiving level at the receiver side.SOLUTION: A video signal transmitter 10 includes: output means 15 for outputting a video signal to be transmitted to a video signal receiver 20; reception means 13 for receiving the light receiving level of a video signal measured by the video signal receiver 20; output level adjustment means 14 for adjusting a video signal output level output from the output means 15, using the light receiving level; and video signal measurement means 16 for measuring the quality of the video signal of the output level adjusted by the output level adjustment means 14. The output level adjustment means 14 readjusts the output level if the measured video signal quality does not satisfy a predetermined criterion.

Description

  The present invention relates to a video signal transmission apparatus and a video communication system that adjust an output level of a video signal and transmit the video signal to a video signal reception apparatus.

  In recent years, video transmission services using RF (Radio Frequency) have been performed.

  Patent Document 1 describes an array antenna receiving apparatus and transmitting apparatus that can calibrate an RF wireless circuit with high accuracy without depending on a bandwidth in RF wireless communication. Patent Document 2 describes an automatic gain control circuit that reduces the level of a local oscillation signal that leaks from an input terminal and prevents adverse effects on other CATV converters and television receivers when receiving jointly. .

JP 2005-348235 A JP-A-6-133247

  Now, unlike the transmission by IP, the conventional RF video transmission is not a bidirectional communication but a one-way communication of only a downstream RF signal. For this reason, it is not possible to use the upstream signal (response) from the receiving device on the transmitting device side that transmits the image based on the RF signal to the receiving device in the house. For this reason, on the transmission device side, video is transmitted using light of a fixed (constant) output level (output power).

  However, with such a method of transmitting video at a fixed output level, for example, in the case of a cover area close to the transmission device, video is transmitted at an output level higher than necessary, which increases power consumption. Resulting in.

  Also, if the received light level does not meet the specified value even a little on the receiving device side, the image will be disturbed, but the transmitting device side does not know the received light level on the receiving device side, so the image is disturbed due to the lowered received light level. There is no way to rescue.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a video signal transmitting device and a video capable of adjusting the output level of the video signal of the transmitting device based on the light reception level on the receiving device side. It is to provide a communication system.

  In order to achieve the above object, a first aspect of the present invention is a video signal transmitting apparatus, wherein an output means for outputting a video signal to be transmitted to the video signal receiving apparatus, and light reception of the video signal measured by the video signal receiving apparatus. Receiving means for receiving a level from the video signal receiving device; output level adjusting means for adjusting an output level of the video signal output from the output means using the received light reception level; and the output level adjusting means. Video signal measuring means for measuring the quality of the adjusted video signal of the output level, the output level adjusting means, when the quality of the video signal measured by the video signal measuring means does not meet a predetermined standard, The gist is to readjust the output level of the output means.

  In the video signal transmitting apparatus, the output level adjusting unit adjusts the output level of the video signal so that the received light reception level satisfies a predetermined specified value and the quality of the video signal satisfies the predetermined standard. Is the gist.

  In the video signal transmitting apparatus, the output level adjusting means adjusts the output level of the video signal for each port of the output means.

  The second aspect of the present invention is a video communication system comprising a video signal transmission device and a video signal reception device, wherein the video signal transmission device outputs an video signal to be transmitted to the video signal reception device; Using the receiving means for receiving the light reception level of the video signal measured by the video signal receiving apparatus from the video signal receiving apparatus and the received light receiving level, the output level of the video signal output by the output means is adjusted. Output level adjusting means, and video signal measuring means for measuring the quality of the video signal of the output level adjusted by the output level adjusting means, wherein the output level adjusting means is the video signal measured by the video signal measuring means. If the quality of the video does not satisfy a predetermined standard, the output level of the output means is readjusted, and the video signal receiving device transmits the video transmitted from the video signal transmitting device. And summarized in that comprises a light receiving level measuring means for measuring a receiving level of the item, and transmission means for transmitting to transmit the received light level in the video signal transmission device.

  According to the present invention, it is possible to provide a video signal transmission device and a video communication system that can adjust the output level of the video signal of the transmission device based on the light reception level on the reception device side.

1 is an overall configuration diagram of a video communication system showing an example of the present embodiment. It is a functional block diagram which shows the structure of a video signal transmitter. It is a functional block diagram which shows the structure of a video signal receiver. It is a sequence diagram which shows the process of a video signal receiver. It is a sequence diagram which shows the process of a video signal transmitter. It is a figure which shows an example of the reference value of light reception level prescription | regulation value and video signal quality. It is a flowchart which shows the process of a video signal transmitter.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an overall configuration diagram of a video communication system according to the present embodiment. The video communication system according to the present embodiment includes a video signal transmission device 10 disposed in a station and a video signal reception device 20 disposed in a user's home.

  The video signal transmitting device 10 (optical subscriber line terminal (OLT)) wavelength-multiplexes a video signal, which is an RF signal, and an IP signal, and receives a video signal at the user's home via the optical fiber 60. Transmit to device 20. Also, the video signal transmitting apparatus 10 of the present embodiment receives the light reception level of the video signal transmitted by the apparatus 10 from the video signal receiving apparatus 20 at the user's home, and outputs the video signal output level (output) based on the light reception level. Value).

  The illustrated video signal transmission device 10 includes a communication unit 11 and an AMP (amplifier) 12. The communication unit 11 receives a light reception level (IP signal) transmitted from the video signal reception device 20, and receives the video signal. The AMP 12 is instructed to adjust the output level. The AMP 12 outputs a video signal with light of an output level adjusted / instructed by the communication unit 11. Note that the IP signal transmitted from the video signal transmitting apparatus 10 to the video signal receiving apparatus 20 is data output from a network such as the Internet, and the video signal is broadcast / transmitted from a broadcast station, a broadcast provider, etc. (not shown). It is a picture to be done.

  As described above, the video signal transmitting apparatus 10 of the present embodiment is an apparatus in which the communication unit 11 (GE-OLT: Gigabit Ethernet-Optical Line Terminal) and the AMP 12 (V-OLT: Visual-Optical Line Terminal) are integrated. Thus, the IP signal (upstream signal) transmitted from the video signal receiving device 20 can be received.

  The video signal receiver 20 (optical subscriber line network unit (V-ONU: Visual-Optical Network Unit)) receives the video signal transmitted from the video signal transmitter 10 and outputs it to an output device such as the television 40. . Further, the video signal receiving device 20 of the present embodiment measures the light reception level of the video signal received from the video signal transmitting device 10 and transmits the measured light receiving level to the video signal transmitting device 10 via the optical fiber 60.

  Further, the video signal receiving device 20 receives the IP signal transmitted from the video signal transmitting device 10 and transmits it to the IP signal receiving device 30. The IP signal receiving device 30 (GE-ONU: Gigabit Ethernet-Optical Network Unit) outputs the IP signal transmitted from the video signal receiving device 20 to the PC 50.

  FIG. 2 is a functional block diagram showing the configuration of the video signal transmitting apparatus 10. The illustrated video signal transmission apparatus 10 includes a signal transmission / reception unit 13, an output level adjustment unit 14, an AMP output unit 15, and a video signal measurement unit 16. The signal transmission / reception unit 13 and the output level adjustment unit 14 correspond to the communication unit 11 shown in FIG. 1, and the AMP output unit 15 and the video signal measurement unit 16 correspond to the AMP 12 shown in FIG.

  The signal transmission / reception unit 13 (reception unit) transmits / receives various signals to / from the video signal reception device 20. That is, the signal transmission / reception unit 13 wavelength-multiplexes the video signal output from the AMP output unit 15 and the IP signal transmitted from the network, and transmits the multiplexed signal to the video signal receiving device 20 as an optical signal. Further, the signal transmission / reception unit 13 receives an IP signal such as a light reception level of the video signal transmitted from the video signal receiving device 20 and data input from the PC 50.

  The output level adjuster 14 (output level adjuster) adjusts the output level of the video signal output from the AMP output unit 15 using the received light level received from the video signal receiver 20.

  The AMP output unit 15 (output unit) outputs a video signal broadcast from a broadcasting station or the like at an output level instructed by the output level adjusting unit 14 and transmits the video signal to the video signal receiving device 20 via the signal transmitting / receiving unit 13. . The AMP output unit 15 includes a plurality of ports that are connection interfaces with the video signal receiving device 20, and a plurality of video signal receiving devices 20 are connected to each port. The output level adjustment unit 14 adjusts the output level of the video signal for each port.

  The video signal measuring unit 16 (video signal measuring means) measures the quality of the video signal at the output level adjusted by the output level adjusting unit 14. The output level adjusting unit 14 readjusts the output level of the video signal of the AMP output unit 15 when the quality of the video signal measured by the video signal measuring unit 16 does not satisfy a predetermined standard.

  FIG. 3 is a functional block diagram showing the configuration of the video signal receiving apparatus 20. The illustrated video signal receiving apparatus 20 includes a signal transmitting / receiving unit 21 and a received light level measuring unit 22.

  The signal transmission / reception unit 21 (transmission means) receives an optical signal transmitted by wavelength multiplexing from the video signal transmission device 10 and separates it into a video signal and an IP signal. The signal is output to the television 40 and the IP signal is output to the IP signal receiving device 30.

  The signal transmission / reception unit 21 transmits the IP signal of the light reception level of the video signal measured by the light reception level measurement unit 22 to the video signal transmission device 10 at all times (or at a predetermined timing). Note that the signal transmission / reception unit 21 may transmit an alarm / warning to the video signal receiving device 20 together with the light reception level when the light reception level no longer satisfies a predetermined specified value. Further, the signal transmission / reception unit 21 transmits the IP signal (data input from the PC 50) transmitted from the IP signal reception device 30 to the video signal transmission device 10.

  The light reception level measurement unit 22 measures the light reception level of the video signal received by the signal transmission / reception unit 21 from the video signal transmission device 10.

  Next, the processing of this embodiment will be described.

  FIG. 4 is a sequence diagram showing processing of the video signal receiving device 20 of the present embodiment.

  The signal transmitter / receiver 21 of the video signal receiver 20 receives the signal transmitted by the video signal transmitter 10 (S11). A video signal and an IP signal are wavelength-multiplexed with a signal (optical signal) transmitted by the video signal transmitting apparatus 10. The signal transmitting / receiving unit 21 separates the received signal into a video signal and an IP signal using a WDM (Wavelength Division Multiplexing) splitter or the like. Then, the signal transmission / reception unit 21 outputs the video signal to the light reception level measurement unit 22 and the television 40, and outputs the IP signal to the IP signal reception device 30.

  The light reception level measurement unit 22 measures the light reception level of the video signal output from the signal transmission / reception unit 21 and notifies the signal transmission / reception unit 21 (S12). The signal transmission / reception unit 21 transmits an IP signal of the measured light reception level to the video signal reception device 20 (S13). The signal transmitting / receiving unit 21 compares the measured light reception level with a predetermined light reception level prescribed value (for example, +1 dB to -11 dB), and if the prescribed value is not satisfied, an alarm / warning is issued together with the light reception level. It may be transmitted to the video signal receiving device 20. That is, when the received light level is lower than the lower limit value of the specified value, the image is disturbed, and when the received light level is higher than the upper limit value of the specified value, the video signal is transmitted with an excessive output level, Since unnecessary power consumption occurs, not only the light reception level but also an alarm is transmitted to notify the video signal transmitting apparatus 10 that the output level is inappropriate.

  FIG. 5 is a sequence diagram showing processing of the video signal transmitting apparatus 10 of the present embodiment.

  The signal transmission / reception unit 13 of the video signal transmission device 10 receives the light reception level of the video signal transmitted from the video signal reception device 20 in S13 of FIG. 4, and outputs the light reception level to the output level adjustment unit 14 (S21). .

  The output level adjustment unit 14 adjusts the output level of the video signal output from the AMP output unit 15 using the received light level received from the signal transmission / reception unit 13 (S22). Specifically, the output level adjustment unit 14 adjusts the output level of the video signal so that the light reception level satisfies a predetermined specified value.

  In the present embodiment, the output level of the video signal is adjusted so that the light reception level becomes the lower limit value of the predetermined specified value. For example, as shown in FIG. 6, the prescribed value of the light reception level of the video signal on the video signal receiving device 20 side is assumed to be +1 dB to −11 dB. The received light level of the video signal received from the video signal receiving device 20 is +5 dB (FIG. 6A). At this time, the output level of the video signal output from the AMP output unit 15 of the video signal transmitting device 10 is +17 dB. (FIG. 6B).

  In this case, the output level adjustment unit 14 adjusts the output level so that the light reception level on the video signal receiving device 20 side becomes the lower limit (−11 dB) of the specified value. That is, a value obtained by subtracting the difference between the light reception level and the lower limit value of the specified value from the current output level is determined as the output level. In the example shown in FIG. 6, +1 dB (= 17 dB − (+ 5 dB − (− 11 dB)) is determined as the output level.

  Then, the output level adjustment unit 14 instructs the determined output level to the AMP output unit 15 (S23).

  The AMP output unit 15 adjusts the output of the video signal at the instructed output level, and outputs the video signal at the adjusted output level to the video signal measuring unit 16 (S24).

  The video signal measurement unit 16 measures the quality of the video signal output from the AMP output unit 15 (S25), and sends the measured video signal quality to the output level adjustment unit 14 (S26). In the present embodiment, CNR (Carrier to Noise Ratio) is used as the video signal quality, but other than this, CSO (Composite Second Order beat), CTB (Composite Triple Beat), etc. may be used. These plural video signal qualities may be measured.

  When receiving the video signal quality measured by the video signal measuring unit 16, the output level adjusting unit 14 determines whether or not the quality satisfies a predetermined standard (S27). As a reference for video signal quality, for example, as shown in FIG. 6B, CNR: 44 dB is used. When the video signal quality satisfies a predetermined standard (when it is equal to or higher than the reference value), the output level adjustment unit 14 instructs the AMP output unit 15 to output the video signal at the output level instructed in S23. Thereby, the AMP output unit 15 outputs the video signal at the output level instructed in S23, and transmits the video signal to the video signal receiving device 20 via the signal transmitting / receiving unit 13 (S28).

  On the other hand, when the video signal quality does not satisfy the predetermined standard (less than the standard value), the output level adjustment unit 14 returns to S22 and readjusts the output level. For example, the output level instructed in the previous S22 is determined by a predetermined value and the output level increased, the determined output level is instructed to the AMP output unit 15, and the subsequent processing is performed. Specifically, when the output level is determined to be +1 dB in the previous S22, and the video signal quality does not satisfy the standard at this time, the output level adjusting unit 14 increases, for example, +2 dB increased by a predetermined value from +1 dB. It may be determined as an output level.

  FIG. 7 is a flowchart showing processing of the video signal transmitting apparatus 10 described in FIG. The AMP output unit 15 of the video signal transmission device 10 of the present embodiment includes a plurality of ports (16 ports in the example shown in FIG. 1), and adjusts the output level of the video signal for each port. To do.

  The signal transmitting / receiving unit 13 receives the IP signal in which the light reception level of the video signal is set from the video signal receiving device 20, and outputs the IP signal to the output level adjusting unit 14 (S31). It is assumed that a user ID for identifying the user (or the video signal receiving device 20) is added to the IP signal together with the light reception level.

  The output level adjustment unit 14 specifies a port corresponding to the user ID of the received IP signal with reference to a port correspondence table stored in a storage unit (not shown). Then, the output level adjustment unit 14 determines whether or not the light reception level of the video signal output from the specified port is excessive or insufficient (whether it is appropriate) (S32). For example, as described with reference to FIG. 5, when the light reception level of the port is the lower limit value of the predetermined specified value, it is determined that there is no excess or deficiency (S32: YES), and the output level of the port is adjusted. Absent. In this case, the AMP output unit 15 transmits the video signal to the video signal receiving device 20 connected to the port with the output level as it is (S33).

  On the other hand, if the light reception level is excessive or insufficient (S32: NO), the output level adjustment unit 14 adjusts the output level of the port (S34). When the light reception level is excessive or insufficient, for example, the case where the light reception level is smaller than a predetermined lower limit value or the light reception level exceeds a predetermined lower limit value may be considered. . Here, as described with reference to FIG. 5, the output level adjustment unit 14 makes the light reception level of the port the lower limit value of the predetermined light reception level prescribed value, that is, the output level of the port is not excessive or insufficient. Determine and adjust the video signal output level.

  Specifically, the output level adjustment unit 14 instructs the AMP output unit 15 to set the output level determined by the port. The AMP output unit 15 outputs the video signal of the designated port to the video signal measuring unit 16 at the designated output level. The video signal measurement unit 16 measures the quality of the input video signal and outputs the measurement result to the output level adjustment unit 14.

  The output level adjustment unit 14 determines whether or not the video signal quality measured by the video signal measurement unit 16 satisfies a predetermined standard (S35). If the predetermined standard is satisfied (S35: YES), the AMP output unit 15 transmits the video signal to the video signal receiving device 20 connected to the port at the output level adjusted in S34 (S36). On the other hand, if the predetermined standard is not satisfied (S35: NO), the process returns to S34, and the adjustment of the output level of the video signal is repeated until the video signal quality satisfies the predetermined standard.

  Note that the process shown in FIG. 7 is repeatedly performed every time the received light level is received from the video signal receiving apparatus 20 (or at a predetermined timing). As a result, the video signal transmitting apparatus 10 can quickly transmit a video signal at an appropriate output level in accordance with a change in the light reception level that is constantly transmitted.

  Further, when a plurality of video signal receiving devices 20 at user's homes are connected to each port, the minimum light receiving level among the light receiving levels respectively transmitted from the plurality of video signal receiving devices 20 connected to each port. 7 is selected and the output level shown in FIG. 7 is adjusted using the minimum received light level.

  As described above, the video signal transmission device 10 of the present embodiment is an integrated video signal transmission device 10 in which the communication unit 11 and the AMP 12 are integrated. As a result, the video signal transmitting apparatus 10 of the present embodiment can receive an IP signal from the video signal receiving apparatus 20 in the house, and the video signal receiving apparatus 20 receives the video signal transmitted from the video signal transmitting apparatus 10. The light reception level is measured and transmitted to the video signal transmission device 10, and the video signal transmission device 10 can adjust the output level of the video signal using the light reception level.

  As described above, in the present embodiment, by feeding back the light reception level measured by the video signal receiving device 20 in the home to the video signal transmitting device 10, the video signal transmitting device 10 is actually connected to the video signal receiving device 20. The output level can be adjusted to the optimum level according to the light reception level, and the power consumption can be reduced. In other words, it is possible to adjust the output level of the video signal appropriately according to the size of the cover area of the user's house that provides the video signal, and power saving can be realized by adjusting the output level. For example, by adjusting the output level so as to be the lower limit value of the prescribed value of the received light level, the video signal can be transmitted at the minimum necessary output level, and the power consumption can be further reduced.

  In this embodiment, the output level of the video signal is adjusted so that the light reception level satisfies a predetermined specified value and the quality of the video signal satisfies a predetermined standard. That is, by adjusting the output level by using the video signal quality together with the light reception level, the output level is adjusted according to the area of the cover area while ensuring the video quality, and the consumption of the AMP output unit 15 with high power consumption. Electric power can be suppressed.

  In this embodiment, the output level is adjusted for each port of the AMP output unit 15. As a result, in the past, video signals were transmitted to each port at a uniform fixed output level, but in this embodiment, an optimum output level can be set for each port, thus reducing power consumption. can do.

  Further, the video signal receiving device 20 of the present embodiment always measures the light reception level of the video signal (or at a predetermined timing) and transmits it to the video signal transmission device 10 so that the light reception level is a predetermined value due to some trouble. In such a case, the video signal receiving device 20 can immediately adjust the output level so that the output level is increased, thereby relieving the service interruption time of the video signal due to the failure. Further, when the video signal receiving device 20 does not satisfy the specified value, the video signal receiving device 20 needs to adjust the output level surely by transmitting an alarm to the video signal transmitting device 10 together with the received light level. It can be reliably detected.

  In addition, this invention is not limited to the said embodiment, Many deformation | transformation are possible within the range of the summary.

10: Video signal transmission device 11: Communication unit 12: AMP
13: Signal transmission / reception unit 14: Output level adjustment unit 15: AMP output unit 16: Video signal measurement unit 20: Video signal reception unit 21: Signal transmission / reception unit 22: Light reception level measurement unit 30: IP signal reception unit 40: Television 50: PC

Claims (4)

A video signal transmission device,
An output means for outputting a video signal to be transmitted to the video signal receiving device;
Receiving means for receiving the light reception level of the video signal measured by the video signal receiving device from the video signal receiving device;
Output level adjusting means for adjusting the output level of the video signal output by the output means using the received light reception level;
Video signal measuring means for measuring the quality of the video signal at the output level adjusted by the output level adjusting means,
The video signal transmitting apparatus, wherein the output level adjusting means readjusts the output level of the output means when the quality of the video signal measured by the video signal measuring means does not satisfy a predetermined standard. The video signal transmitting apparatus according to claim 1,
The output level adjusting means adjusts the output level of the video signal so that the received light reception level satisfies a predetermined specified value and the quality of the video signal satisfies the predetermined standard. apparatus. The video signal transmission device according to claim 1 or 2,
The output level adjusting means adjusts the output level of the video signal for each port of the output means. A video communication system comprising a video signal transmitting device and a video signal receiving device,
The video signal transmission device includes:
An output means for outputting a video signal to be transmitted to the video signal receiving device;
Receiving means for receiving the light reception level of the video signal measured by the video signal receiving device from the video signal receiving device;
Output level adjusting means for adjusting the output level of the video signal output by the output means using the received light reception level;
Video signal measuring means for measuring the quality of the video signal at the output level adjusted by the output level adjusting means,
The output level adjusting means readjusts the output level of the output means when the quality of the video signal measured by the video signal measuring means does not satisfy a predetermined standard;
The video signal receiving device is:
A light receiving level measuring means for measuring a light receiving level of a video signal transmitted from the video signal transmitting device;
Transmitting means for transmitting the received light level to the video signal transmitting device.

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