JP5996976B2 - Wireless transmission system - Google Patents

Description

  The present invention relates to a wireless transmission system including a transmitter having a tuner for receiving television broadcasts and a receiver having a monitor.

  2. Description of the Related Art Conventionally, a wireless transmission system including a transmission device having a TV broadcast reception tuner unit and a reception device having a monitor unit is known. According to such a wireless transmission system, the user can carry the receiving device to a favorite place and watch a TV program at a favorite place as long as wireless communication between the transmitting device and the receiving device is possible. can do.

JP 2009-171181 A

  If the time until the video display is started after the power-on operation of the receiving device is long, the user will be dissatisfied with the wireless transmission system. It is desirable that the time until video display starts is shorter.

  Note that the wireless transmission system disclosed in Patent Document 1 (referred to as “television receiver with built-in wireless communication device” in Patent Document 1) is a receiving device (referred to as “monitor unit” in Patent Document 1). When the main power source of the transmitter is turned off, the transmission device (referred to as a “tuner unit” in Patent Document 1) is turned off in conjunction with the power source to save power. Once the entire transmitter is turned off, even if the main power of the receiver is turned on after that, the wireless communication between the receiver and the transmitter is disabled, and the user has to go to the place where the transmitter is installed. If the transmitter is not turned on, the television program cannot be viewed again.

  Therefore, the wireless transmission system disclosed in Patent Document 1 starts video display after performing a power-on operation of the receiving device when the receiving device is turned on within the wireless transmission possible area of the transmitting device. It is not possible to shorten the time until it is done.

  In view of the above situation, the present invention is a time from when a power-on operation of a receiving device is performed until video display is started when the receiving device is turned on within the wireless transmission possible area of the transmitting device. An object of the present invention is to provide a wireless transmission system that can shorten the time.

  In order to achieve the above object, a wireless transmission system according to the present invention is a wireless transmission system including a transmission device and a reception device, and the transmission device includes a television broadcast reception tuner unit and the television broadcast reception tuner unit. A first wireless communication unit that transmits a radio signal obtained by modulating a video signal and an audio signal output from the receiver, wherein the receiving device demodulates the received radio signal to obtain a video signal and an audio signal, A second wireless communication unit that outputs the acquired video signal and audio signal; and a monitor unit that displays a video based on the video signal output from the second wireless communication unit; When an SSID (Service Set Identifier) signal is received from a device and it is confirmed that the SSID signal from the receiving device and the SSID signal of the transmitting device itself are the same In addition, the television broadcast receiving tuner unit is set to a power-on state (first configuration) without waiting for establishment of a wireless connection between the transmitting device and the receiving device.

  According to such a configuration, compared to the configuration in which the TV broadcast reception tuner unit is powered on after the wireless connection between the transmission device and the reception device is established, the wireless transmission possible region of the transmission device When the receiver is turned on, the time from when the receiver is turned on until the video display is started can be shortened.

  In the wireless transmission system having the first configuration, the transmission device receives an SSID signal from the reception device, and the SSID signal from the reception device and the SSID signal of the transmission device itself are the same. Even if it is confirmed that the establishment of the wireless connection between the transmitting device and the receiving device has failed after that, the state of the tuner for receiving the television broadcast is changed to the SSID signal from the receiving device. It is preferable to adopt a configuration (second configuration) in which the SSID signal from the receiving device and the SSID signal of the transmitting device itself are confirmed to be the same as when the SSID signal is confirmed to be the same.

  According to such a configuration, it is possible to prevent the TV broadcast receiving tuner unit from being unnecessarily left in a power-on state, thereby suppressing unnecessary power consumption of the TV broadcast receiving tuner unit. Can do.

  In the wireless transmission system having the first or second configuration, it is preferable that the transmitting device is a wireless client and the receiving device is a wireless access point (third configuration).

  According to such a configuration, it is possible to further shorten the time from when the power-on operation of the receiving apparatus is performed until the video display is started.

  According to the present invention, when the receiving device is powered on within the wireless transmission possible area of the transmitting device, it is possible to shorten the time from when the power of the receiving device is turned on until the video display is started. A wireless transmission system that can be realized is realized.

It is a figure showing an example of 1 composition of a radio transmission system concerning the present invention. It is a figure which shows the procedure for establishing the wireless connection which concerns on 1st Embodiment. It is a flowchart which shows the operation | movement performed when a transmitter receives an SSID signal. It is a figure which shows the procedure for establishing the wireless connection which concerns on 2nd Embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating a configuration example of a wireless transmission system according to the present invention. In order to avoid complication of the drawing, in FIG. 1, illustration of a power supply line for supplying power from the power supply circuit 27 to each unit is omitted. The wireless signal transmission system illustrated in FIG. 1 includes a transmission device 10 and a reception device 20.

  First, the transmission device 10 will be described. The transmission device 10 includes a distributor 11, a television broadcast receiving tuner unit 12, a wireless communication unit 13, a control unit 14, and a power supply circuit 15.

  The distributor 11 distributes two television broadcast signals such as a terrestrial digital television broadcast signal and a satellite digital television broadcast signal, outputs one to the outside, and outputs the other to the TV broadcast receiving tuner unit 12.

  The TV broadcast receiving tuner unit 12 performs channel selection processing on the TV broadcast signal output from the distributor 11, acquires the video signal and audio signal of the reception channel, and wirelessly transmits the acquired video signal and audio signal. Output to the communication unit 13. The video signal and audio signal output from the TV broadcast receiving tuner unit 12 may be any type of signal, for example, either an analog signal or a digital signal, either a compressed signal or an uncompressed signal. . Therefore, if necessary, a signal processing circuit that executes predetermined signal processing after channel selection processing may be provided in the tuner 12 for receiving television broadcasts.

  The TV broadcast receiving tuner unit 12 includes a power supply circuit 12A. The power supply circuit 12A uses the DC voltage supplied from the power supply circuit 15 to generate a power supply voltage necessary for operating the TV broadcast receiving tuner unit 12.

  The TV broadcast receiving tuner unit 12 has a power-on state in which a video signal and an audio signal can be output, a power-off state in which a video signal and an audio signal cannot be output, and power consumption is smaller than that in the power-on state. More than the power-off state, video signals and audio signals cannot be output, and the transition time when switching to the power-on state can take three states: a standby state shorter than the power-off state. . Unlike this configuration example, a TV broadcast receiving tuner unit that can only take two states, a power-on state and a power-off state, may be used.

  The radio communication unit 13 transmits a radio signal obtained by modulating the video signal and the audio signal output from the TV broadcast receiving tuner unit 12. The modulation scheme and the frequency band of the radio signal are not particularly limited. For example, a modulation scheme and a radio signal frequency band conforming to IEEE802.11a, IEEE802.11g, IEEE802.11b, or the like can be used. The wireless communication unit 13 includes a power supply circuit 13A. The power supply circuit 13 </ b> A generates a power supply voltage necessary for operating the wireless communication unit 13 using the DC voltage supplied from the power supply circuit 15.

  The control unit 14 controls the operation of the television broadcast receiving tuner unit 12 and the operation of the wireless communication unit 13. The control unit 14 uses the DC voltage supplied from the power supply circuit 15 as the power supply voltage of the control unit 14 itself.

  The power supply circuit 15 converts a commercial AC voltage supplied from the outside into a DC voltage having a predetermined value and supplies the DC voltage to the power supply circuit 12 </ b> A, the power supply circuit 13 </ b> A, and the control unit 14.

  Next, the receiving device 20 will be described. The receiving device 20 includes a wireless communication unit 21, a liquid crystal monitor unit 22, an audio output unit 23, a control unit 24, a remote control receiving unit 25, a battery 26, and a power circuit 27.

  The wireless communication unit 21 demodulates the received wireless signal to acquire a video signal and an audio signal, and outputs the acquired video signal and audio signal. The wireless communication unit 21 includes a power supply circuit 21A. The power supply circuit 21 </ b> A generates a power supply voltage necessary for operating the wireless communication unit 21 using the DC voltage supplied from the power supply circuit 27. If necessary, a signal processing circuit that performs predetermined signal processing on the video signal output from the wireless communication unit 21 is provided between the wireless communication unit 21 and the liquid crystal monitor unit 22. A signal processing circuit that performs predetermined signal processing on the output audio signal may be provided between the wireless communication unit 21 and the audio output unit 23.

  The liquid crystal monitor unit 22 displays an image based on the image signal output from the wireless communication unit 21. The liquid crystal monitor unit 22 has a built-in power supply circuit 22A. The power supply circuit 22 </ b> A generates a power supply voltage necessary for operating the liquid crystal monitor unit 22 using the DC voltage supplied from the power supply circuit 27.

  The audio output unit 23 includes, for example, an amplifier and a speaker. The audio output unit 23 uses a DC voltage supplied from the power supply circuit 27 as a power supply voltage of the audio output unit 23 itself, and is based on an audio signal output from the wireless communication unit 21. Is output.

  The control unit 24 controls the operation of the wireless communication unit 21, the operation of the liquid crystal monitor unit 22, and the operation of the audio output unit 23 based on a remote control code signal output from the remote control receiving unit 25. The control unit 24 uses the DC voltage supplied from the power supply circuit 27 as the power supply voltage of the control unit 24 itself.

  The remote control receiving unit 25 receives an infrared remote control signal transmitted from a remote controller (not shown), and outputs a remote control code signal corresponding to the received infrared remote control signal to the control unit 24.

  The power supply circuit 27 converts the DC voltage output from the battery 26 into a DC voltage having a predetermined value and supplies the DC voltage to each unit of the receiving device 20.

  The receiving device 20 accepts an infrared remote control signal in a power-on state in which all operations are possible, a power-off state in which all operations are impossible, power consumption is less than the power-on state and more than the power-off state. It is possible to take three states: a standby state, which is only possible. For example, the power-on state and the standby state of the receiving device 20 can be switched by providing a power key on a remote controller (not shown) by operating the power key, and switching between the power-on state and the power-off state of the receiving device 20. The receiver 20 may be provided with a main power switch so that it can be operated by operating the main power switch. Unlike the present configuration example, a receiving device that can only take two states, a power-on state and a power-off state, or a receiving device that can take only two states, a power-on state and a standby state, is used. It doesn't matter.

<First Embodiment>
FIG. 2 is a diagram illustrating a procedure for establishing a wireless connection according to the first embodiment. In the present embodiment, the transmission device 10 is a wireless client, receiving device 20 is a wireless access point.

  The receiving device 20 transmits the SSID signal of the receiving device 20 itself from the wireless communication unit 21.

  The transmission device 10 receives the SSID signal from the reception device 20 by the wireless communication unit 13, and if the SSID signal from the reception device 20 and the SSID signal of the transmission device 10 itself are the same, the SSID signal of the transmission device 10 itself. Is transmitted from the wireless communication unit 13 (time (A)).

  The reception device 20 receives the SSID signal from the transmission device 10 by the wireless communication unit 21. If the SSID signal from the transmission device 10 and the SSID signal of the reception device 20 itself are the same, the authentication confirmation data request signal is wirelessly transmitted. It transmits from the communication part 21 ((B) time).

  The transmission device 10 receives the authentication confirmation data request signal from the reception device 20 by the wireless communication unit 13, and transmits the authentication confirmation data from the wireless communication unit 13 in response to the authentication confirmation data request signal (at time (C)). .

  The reception device 20 receives the authentication confirmation data from the transmission device 10 by the wireless communication unit 21, authenticates the transmission device 10 using the authentication confirmation data, and obtains an authentication confirmation result (“authentication success”, “authentication failure”). Any one) is transmitted from the wireless communication unit 21 (time (D)).

  The transmission device 10 receives the authentication confirmation result from the reception device 20 by the wireless communication unit 13, and transmits a line connection request signal from the wireless communication unit 13 if the authentication confirmation result is “authentication successful” ((E)). Time).

  The receiving device 20 receives the line connection request signal from the transmitting device 10 by the wireless communication unit 21, and transmits a line connection permission signal from the wireless communication unit 21 in response to the line connection request signal (at time (F)).

  The transmission device 10 receives the line connection permission signal from the reception device 20 by the wireless communication unit 13 (at (G)). (G) At the time, the wireless connection between the transmission device 10 and the reception device 20 is established.

  In the present embodiment, at time (A), the transmission apparatus 10 performs the operation shown in the flowchart of FIG.

  The control unit 14 of the transmission device 10 detects the SSID signal from the reception device 20 (step S1), and determines whether the SSID signal from the reception device 20 and the SSID signal of the transmission device 10 itself are the same. (Step S2).

  When the SSID signal from the receiving device 20 and the SSID signal of the transmitting device 10 itself are the same (YES in step S2), the control unit 14 changes the TV broadcast receiving tuner unit 12 to a power-on state (step S3). ), The flow operation ends.

  When the SSID signal from the receiving device 20 and the SSID signal of the transmitting device 10 itself are not the same (NO in step S2), the control unit 14 is in a state where the TV broadcast receiving tuner unit 12 is not in the power-on state (power-off state or (Standby state) is maintained (step S4), and the flow operation is terminated.

  When the TV broadcast receiving tuner unit 12 is changed to the power-on state, it takes about ten seconds or more after the change is started to complete the change. Further, it takes about 20 seconds from the time (A) to the time (G). Accordingly, if the TV broadcast receiving tuner unit 12 is changed to the power-on state from the time (A) as in the present embodiment, the change is completed by the time (G). Compared to the configuration in which the tuner unit 12 is changed to the power-on state, when the receiving device 20 is turned on in the wireless transmission possible area of the transmitting device 10, the power-on operation of the receiving device 20 is performed. The time until video display on the liquid crystal monitor unit 22 is started can be shortened.

  Note that the series of procedures shown in FIG. 2 may not proceed smoothly due to deterioration of the communication status. In such a case, a normal retry process or the like is performed. However, although the time (A) has been reached, the wireless connection may fail to be established without reaching the time (G). is there.

  Therefore, in the present embodiment, the transmitting apparatus 10 determines that the wireless connection between the transmitting apparatus 10 and the receiving apparatus 20 has failed to be established after starting the process of step S3 in FIG. In this case, the state of the TV broadcast receiving tuner unit 12 is returned to the state immediately before the time point (A), that is, the state not in the power-on state (power-off state or standby state). Note that, as a determination criterion for determining that the wireless connection between the transmission device 10 and the reception device 20 has failed after starting the processing of step S3 in FIG. 3 at the time (A), for example, (A) When the wireless connection between the transmission device 10 and the reception device 20 cannot be established even when the elapsed time from the time reaches a preset upper limit time, the determination criterion for determining that the wireless connection has failed and the number of retries are When the preset upper limit number is reached, the subsequent connection establishment procedure is canceled, and a determination criterion for determining that the wireless connection establishment has failed can be cited.

  As a result, it is possible to prevent the TV broadcast reception tuner unit 12 from being unnecessarily left in the power-on state in a state where the wireless connection between the transmission device 10 and the reception device 20 is not established. The wasteful power consumption of the TV broadcast receiving tuner unit 12 can be suppressed.

  Further, in the present embodiment, when the control unit 14 of the transmission device 10 determines that the wireless connection between the transmission device 10 and the reception device 20 is disconnected, the television broadcast reception tuner unit 12 is not in a power-on state ( The useless power consumption of the TV broadcast receiving tuner unit 12 is suppressed by setting the power off state or the standby state.

Second Embodiment
FIG. 4 is a diagram illustrating a procedure for establishing a wireless connection according to the second embodiment. In the present embodiment, the transmission device 10 is a wireless access point, and the reception device 20 is a wireless client.

  The transmission device 10 transmits the SSID signal of the transmission device 10 itself from the wireless communication unit 13.

  The reception device 20 receives the SSID signal from the transmission device 10 by the wireless communication unit 21, and if the SSID signal from the transmission device 10 and the SSID signal of the reception device 20 itself are the same, the SSID signal of the reception device 20 itself. Is transmitted from the wireless communication unit 21 (time (a)).

  The transmission device 10 receives the SSID signal from the reception device 20 by the wireless communication unit 13, and if the SSID signal from the reception device 20 and the SSID signal of the transmission device 10 itself are the same, the authentication confirmation data request signal is wirelessly transmitted. It transmits from the communication part 13 ((b) time).

  The reception device 20 receives the authentication confirmation data request signal from the transmission device 10 by the wireless communication unit 21, and transmits the authentication confirmation data from the wireless communication unit 21 according to the authentication confirmation data request signal (at time (c)). .

  The transmission device 10 receives the authentication confirmation data from the reception device 20 by the wireless communication unit 13, authenticates the reception device 20 using the authentication confirmation data, and obtains an authentication confirmation result (“authentication success”, “authentication failure”). Any one) is transmitted from the wireless communication unit 13 (at time (d)).

  The reception device 20 receives the authentication confirmation result from the transmission device 10 by the wireless communication unit 21, and transmits a line connection request signal from the wireless communication unit 21 if the authentication confirmation result is “authentication successful” ((e). Time).

  The transmission device 10 receives the line connection request signal from the reception device 20 by the wireless communication unit 13, and transmits a line connection permission signal from the wireless communication unit 13 in response to the line connection request signal (at time (f)).

  The reception device 20 receives the line connection permission signal from the transmission device 10 by the wireless communication unit 21 (at time (g)). (G) At the time, the wireless connection between the transmission device 10 and the reception device 20 is established.

  In the present embodiment, at time (b), the transmission apparatus 10 performs the operation shown in the flowchart of FIG. Since the operation itself shown in the flowchart of FIG. 3 is the same as that of the first embodiment, description thereof is omitted.

  When the TV broadcast receiving tuner unit 12 is changed to the power-on state, it takes about ten seconds or more after the change is started to complete the change. Further, it takes about 20 seconds from the time point (a) to the time point (g). Accordingly, if the TV broadcast receiving tuner unit 12 is changed to the power-on state from the time (b) as in the present embodiment, the change is completed by the time (g), and therefore the TV broadcast reception is performed from the time (g). Compared to the configuration in which the tuner unit 12 is changed to the power-on state, when the receiving device 20 is turned on in the wireless transmission possible area of the transmitting device 10, the power-on operation of the receiving device 20 is performed. The time until video display on the liquid crystal monitor unit 22 is started can be shortened.

  Note that the series of procedures illustrated in FIG. 4 may not proceed smoothly due to deterioration of the communication status. In such a case, a normal retry process or the like is performed. However, although the time point (b) has been reached, the wireless connection establishment may fail without reaching the time point (g). is there.

  Therefore, in the present embodiment, the transmitting apparatus 10 determines that the wireless connection between the transmitting apparatus 10 and the receiving apparatus 20 has failed to be established after starting the process of step S3 in FIG. 3 at time (b). In this case, the state of the TV broadcast receiving tuner unit 12 is returned to the state immediately before the time point (b), that is, the state not in the power-on state (power-off state or standby state). As a criterion for determining that the wireless connection between the transmission device 10 and the reception device 20 has failed after starting the process of step S3 in FIG. 3 at the time (b), for example, (b) When the wireless connection between the transmission device 10 and the reception device 20 cannot be established even when the elapsed time from the time reaches a preset upper limit time, the determination criterion for determining that the wireless connection has failed and the number of retries are When the preset upper limit number is reached, the subsequent connection establishment procedure is canceled, and a determination criterion for determining that the wireless connection establishment has failed can be cited.

  As a result, it is possible to prevent the TV broadcast reception tuner unit 12 from being unnecessarily left in the power-on state in a state where the wireless connection between the transmission device 10 and the reception device 20 is not established. The wasteful power consumption of the TV broadcast receiving tuner unit 12 can be suppressed.

  Further, in the present embodiment, when the control unit 14 of the transmission device 10 determines that the wireless connection between the transmission device 10 and the reception device 20 is disconnected, the television broadcast reception tuner unit 12 is not in a power-on state ( The useless power consumption of the TV broadcast receiving tuner unit 12 is suppressed by setting the power off state or the standby state.

DESCRIPTION OF SYMBOLS 10 Transmitter 11 Distributor 12 Television broadcast receiving tuner unit 12A, 13A, 15 21A, 22A, 27 Power supply circuit 13, 21 Wireless communication unit 14, 24 Control unit 20 Receiver device 22 Liquid crystal monitor unit 23 Audio output unit 25 Remote control reception Part 26 Battery

Claims (3)

A wireless transmission system comprising a transmitter and a receiver,
The transmitter is
A tuner for receiving TV broadcasts;
A first wireless communication unit that transmits a radio signal obtained by modulating a video signal and an audio signal output from the TV broadcast receiving tuner unit;
The receiving device is:
A second wireless communication unit that demodulates the received wireless signal to acquire a video signal and an audio signal, and outputs the acquired video signal and audio signal;
A monitor unit for displaying video based on a video signal output from the second wireless communication unit,
The transmitter is
Wireless connection between the transmitting device and the receiving device when the SSID signal from the receiving device is received and it is confirmed that the SSID signal from the receiving device and the SSID signal of the transmitting device itself are the same The wireless transmission system is characterized in that the television broadcast receiving tuner unit is turned on without waiting for the establishment of the radio broadcast system. The transmitter is
Despite receiving the SSID signal from the receiving device and confirming that the SSID signal from the receiving device and the SSID signal of the transmitting device itself are the same, then the transmitting device and the receiving device If it is determined that the establishment of the wireless connection has failed,
The state of the tuner for receiving TV broadcasts,
The wireless transmission system according to claim 1, wherein the wireless transmission system is returned from a power-on state to a power-off state or a standby state .   The wireless transmission system according to claim 1, wherein the transmitting device is a wireless client, and the receiving device is a wireless access point.

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