JP2013150282A - Wireless base station device, wireless terminal and wireless transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for controlling the power supply of a source apparatus more efficiently.SOLUTION: The wireless base station device comprises: determination means for monitoring WFD IE (Wi-Fi Display information element) included in a Probe Request signal from a sink apparatus, and determining whether or not a mobile terminal is an apparatus for WFD from the WFD IE; and listing means for acquiring the identification information of the mobile terminal determined to be an apparatus for WFD, and listing the identification information. The wireless terminal comprises: reference means connected with the wireless base station device at a set period T1 and referring a list indicating whether or not an apparatus for WFD exist; and power supply control means for turning power on so as to provide a WFD service when an apparatus for WFD exists in the area of the wireless base station device.

Description

  Embodiments described herein relate generally to a wireless transmission system using a wireless terminal device.

<Background>
In recent years, PC peripheral devices are becoming wireless and mobile terminals are diversifying. Wireless PC peripherals include wireless LAN (Wi-Fi (R)) for wired LAN (Ethernet (registered trademark)), and USB connected HDD or memory. Is a wireless external storage medium such as NAS (Network Attached Storage), and D-Sub and HDMI (R) are wireless displays (eg Wi-Fi Display (R), Intel WiDi (R), Amimon WHDI ( R)) and other displays are expected to become wireless. On the other hand, there have been notebook computers, mobile phones, digital cameras, digital audio players, digital video cameras, etc., but mobile terminals have been diversified in recent years, such as tablet computers, smartphones, and digital photo frames. It is a feature.

  Attention has also been focused on wireless display. As an early use case, Wireless Display technology is assumed to be used to transmit video from a notebook computer to a television, and is mainly used in the same room. The general procedure is to turn on the power of the source device or sink terminal, start an application for Wireless Display, establish an interconnection, and wirelessly transmit video from the source device to the sink terminal. is there.

  As a usage scene, you can watch your photos and presentations on the big screen in the same room. In this case, you can manually turn on / off the source device or sink terminal only when using Wireless Display. Easy. As described above, it is assumed that the source device is mainly a mobile device such as a laptop computer, and the sink terminal is a fixed device such as a television. For this reason, in the wireless display technology, there is almost no assumption that the source terminal is a fixed device and the sink terminal is a mobile device.

<Conventional technology>
In the case of Wi-Fi, which is one of the wireless technologies, the connection method can be via P2P or AP. In the case of connection via an AP, the client performs a passive scan or an active scan in order to scan the AP. In the case of Active Scan, a Probe Request is transmitted and a Probe Response transmitted from the AP is received. In the case of Passive Scan, a Beacon is received from the AP.

  Hereinafter, the description will be made on the premise of Active Scan that is generally used for mobile terminals. However, the present invention is not limited to Active Scan. Next, an authentication request is sent from the client to the AP, and the AP returns an authentication response. After that, an association request is sent from the client to the AP, and the AP returns an association response, the authentication is completed, and the Wi-Fi connection is completed. On the other hand, in the case of P2P connection, one terminal is a group owner and the other is a client, and can be connected one-to-one without an AP. In addition, in Wi-Fi Display (WFD), which is one of the Wireless Display technologies, in addition to the above, WFD IE (Wi-Fi Display information element) is included in Beacon, Probe Request, and Probe Response. It is described in the Fi Display specification. WFD IE enables discovery of WFD compatible devices via P2P or AP.

<Issues>
In the case of the above usage scene, since the sink terminal is assumed to be a mobile terminal, the user is not necessarily near the source device. Therefore, if the source device is turned off, there is a problem that the user has to move to the room to turn on the source device. In addition, since the power source of the source device is turned on in order to save time and effort, it is a problem to always consume power.

  That is, there is a demand for more efficiently controlling the power source of the source device, but means for realizing such demand is not known.

JP 2010-56951 A

  An object of the embodiment of the present invention is to provide a technique capable of more efficiently controlling the power source of a source device.

  In order to solve the above-described problem, according to the embodiment, the radio base station apparatus monitors a WFD IE (Wi-Fi Display information element) included in a Probe Request signal from a sink device, and the mobile terminal uses the WFD IE. Determining means for determining whether or not the device is a WFD compatible device, and listing means for acquiring identification information of the mobile terminal determined to be the WFD compatible device and listing the identification information.

The functional block block diagram which shows the video display apparatus (system) concerning one Embodiment of this invention. 2 is an exemplary block diagram showing an example of the system configuration of the electronic apparatus of the embodiment. FIG. The schematic block diagram which shows the apparatus (system) which views and listens to the video output of an Example by a sink terminal. The flowchart which shows the apparatus (system) of AP of a 1st Example. 1 is a flowchart illustrating an apparatus (system) according to a first embodiment. FIG. 3 is a startup sequence diagram of the source device according to the first embodiment. The flowchart which shows the apparatus (system) of 1st Example 2. FIG. FIG. 6 is a startup sequence diagram of a source device according to the first embodiment. The schematic block diagram which shows the apparatus (system) of a 2nd Example. The flowchart which shows the apparatus (system) of a 2nd Example. The starting sequence figure of the source apparatus of a 2nd Example. The functional block diagram which showed the structural example of base station AP of an Example.

  Embodiments of the present invention will be described below.

(First embodiment)
A first embodiment will be described with reference to FIGS. 1 to 8 and FIG.

<Conventional usage scene>
First, in order to compare the following, video output from video output devices such as STB (Set Top Box) and home video games is encoded via an HDMI cable for video signal encoding or copyright protection. Receiving wireless transmission video signals via wireless display via a source device capable of wireless transmission at a sink terminal such as a tablet PC that can decode video signal decoding or encryption for copyright protection Thus, a description will be given of an example of a usage scene in which a video output of STB is viewed.

  The system procedure in this usage scene is as follows. First, if you want to use the Wireless Display, the user must go to the room with the source device and manually turn on the source device or sink terminal. Thereafter, the source device remains powered on until there is a wireless display connection request from the sink terminal. Wireless Display connection is made via Peer to Peer (P2P) or access point (hereinafter referred to as AP), and Wireless Display connection is established.

  As a conventional technique for solving the above-described problem, there is a method of turning on the power of the source device by using a Wake on (Wireless) LAN function and making a wake up request from the sink terminal to the source device. However, since it is necessary to keep the power source of the wireless communication unit of the source device turned on, the standby power is a problem.

<First embodiment>
The first embodiment takes up a Wi-Fi Display (WFD), which is one of the Wireless Displays, and uses an AP as shown in FIG. By using this method, it is possible to prepare for communication by turning on the source device only when the sink terminal exists in the area of the AP.

  That is, the source device 9 receives video content sent from the video output device 8 through the HDMI interface, and the source device 9 sends the received video content to the sink terminal 10 via the AP 80. At this time, the sink terminal 10 can be turned on as long as it exists in the area of the AP 80.

  Next, prior to explaining FIG. 12 regarding the AP, a mechanism of a related MAC (Media Access control) address will be described. First, there are descriptions of management, control, and data as type values of B3 and B2 as a frame control field of a MAC frame of a wireless packet.

  The management frame includes (1) a beacon (Beacon) frame (broadcast signal) for broadcasting basic information of a wireless cell, (2) an authentication frame for authentication, (3) a base Association, frame, action frame, etc. for exchanging information between a station and a terminal station are defined.

  Next, information elements of each frame stored in the frame body of the management frame are shown.

(1) Beacon
This frame is used to notify various information necessary for communication to neighboring wireless stations. In the infrastructure mode, the base station periodically transmits to inform the terminal station of the presence of the radio cell. In ad hoc mode, the terminal stations that make up the IBSS transmit randomly. The beacon information element is defined in the IEEE 802.11 standard.

(2) Probe Request
This frame is used for the terminal station to inquire about the presence or absence of a wireless cell in the vicinity. The information element for the probe request is defined in the IEEE 802.11 standard.

(3) Probe response
This frame is used for the wireless station to respond to a probe request from the terminal station.

FIG. 12 is a functional block diagram configuring base station 80 which is a radio base station apparatus according to the present embodiment. The base station 80 includes a beacon transmission control unit 1114, an AP control unit 1116, a received packet analysis unit 1118, an AP wireless unit 1119, a transmission unit 1120, a reception unit 1121, an external network communication unit 1122, a transmission unit 1123, and a reception unit 1124. Prepare.

  The beacon transmission control unit 1114 has a function of generating a beacon to be transmitted and controlling the timing of periodic transmission. When an AP control unit 1116 described later receives a packet, the AP control 1116 notifies the beacon transmission control unit 1114 to insert the MAC address into the beacon and transmit the packet. Receiving the notification, the beacon transmission control unit 1114 adds information indicating the MAC address to the beacon to generate a beacon frame. The generated beacon is transmitted in accordance with the transmission timing managed by the beacon transmission control unit 1114.

  The AP control unit 1116 has a function to control the AP wireless unit 1119, a function to notify the beacon transmission control unit 1114 of insertion information to the beacon, a function to access the connection list, and a received packet analysis to be described later. Part 1118 and a function of accessing. The AP control unit 1116 transfers a packet received by the external network communication unit 1122, which will be described later, to the wireless unit 1119 according to the state.

  The received packet analysis unit 1118 has a function of analyzing a packet received by the external network communication unit 1122 and a function of accessing the AP control unit. The received packet analysis unit 1118 refers to the destination MAC address entered in the packet received from the external network communication unit 1122 and notifies the AP control unit 1116 of the presence of the packet to be transferred and its transfer destination MAC address. The AP control unit 1116 determines whether the target having the notified MAC address is being activated or stopped, and determines subsequent processing (described in the explanation of the AP control unit 1116).

  The AP wireless unit 1119 includes a transmission unit 1120 and a reception unit 1121, and has a function of performing an operation based on the Wi-Fi communication protocol.

  The external network communication unit 1122 includes a transmission unit 1123 and a reception unit 1124, and has communication means for the AP 30 to establish connectivity with the external network. Examples of the configuration of the external network communication unit 1122 include wired networks such as Ethernet (registered trademark) and optical communication, wireless communication means such as WiMAX, mobile phone communication means, and PHS. Not.

  In other words, this AP has a Wi-Fi function, and in addition to WFD IE based on WFD IE transmitted at probe request or capability exchange at the time of probe request by active scan or confirmation of performance during association It is possible to determine whether or not the device is a device, and when the terminal is a WFD compatible device, the terminal identification information is listed as described later, and the terminal can refer to the list. It is characterized by that.

  The source device periodically connects to the AP and refers to a list indicating whether or not a WFD-compatible device exists. If a WFD-compatible device exists in the AP area, the WFD service is provided. It is characterized by turning on the power so that it can be done.

  FIG. 4 is a flowchart showing an operation centering on the AP control unit 1116 of the AP. When the AP is powered on (Yes in step S41), the AP receives a Probe Request from the terminal if there is a terminal in the area of the AP. If the AP receives a probe request (Yes in step S42), the AP transmits a probe response to the terminal (step S43). Next, the AP determines whether WFD IE is included in the Probe Request. If the WFD IE is included (Yes in step S44), information on the WFD compatible device is added to the list (step S45). At this time, in the case of Passive Scan, it is confirmed whether the device is a WFD compatible device when confirming Capability. If the link between the AP and the terminal is disconnected (Yes in step S46), the AP performs a disconnection process (step S47). If the terminal is a WFD compatible device (Yes in step S48), the terminal information is deleted from the list (step S49).

  For example, this list has a one-dimensional configuration in which the MAC addresses of the terminals are listed as identification information, and is under the control of the AP control unit 1116.

  FIG. 1 is a functional block diagram showing a video display device 9 (system) according to the embodiment of the wireless terminal device.

  The video display device 9 includes an antenna 60, a tuner 61, a digital demodulator 62, a TS decoder 63, a video decoder 64, an audio decoder 65, a video display control unit 66, an audio presentation control unit 67, a display 68, a speaker 69, and a nonvolatile memory. 70, a CPU 71, a wireless module 72 (including a STA control unit 72a and a STA wireless unit 72b), and an HDMI input unit 73. Furthermore, the STA control unit 72a includes a reception beacon analysis unit (not shown). The STA radio unit 72b includes a receiving unit and a transmitting unit (not shown).

  The reception beacon analysis unit has a function of analyzing the beacon received by the reception unit. When the MAC address is included in the beacon, the reception beacon analysis unit notifies the STA control unit 72a of activation of the STA radio unit 72b.

  The STA control unit 72a has a function of performing state transition of the STA radio unit 72b according to the analysis result in the reception beacon analysis unit. It notifies ON / OFF of the power supply of the STA radio unit 72b. Further, it has a function of recording the state of the STA radio unit 72b.

  The STA radio unit 72b includes a transmission unit and a reception unit, and has a function of performing Wi-Fi communication with the AP 80. The STA wireless unit 72b establishes connectivity to the Internet by having a wireless communication function in accordance with the standard protocol of Wi-Fi communication. Further, the power supply is automatically turned on and off by the control from the STA control unit 72a.

  The antenna 60 receives a digital broadcast broadcast from a broadcast station, and the tuner 61 further performs a channel selection process for this broadcast. Further, the digital demodulator 62, the TS decoder 63, the video decoder 64, and the audio decoder 65 obtain the video content of the digital signal. This digital signal is guided to the video display control unit 66, the audio presentation control unit 67, and output to the display 68 and the speaker 69. The HDMI input unit 73 is configured to input video content of an external digital signal.

Next, with reference to FIG. 2, the configuration of an electronic device that is a wireless terminal device will be described. The electronic apparatus according to the present embodiment is realized by, for example, a notebook portable personal computer 10 that functions as an information processing apparatus.

  As shown in FIG. 2, the computer 10 includes a CPU 101, a north bridge 102, a main memory 103, a south bridge 104, a graphics processing unit (GPU) 105, a video memory (VRAM) 105A, a sound controller 106, a BIOS- ROM 109, LAN controller 110, hard disk drive (HDD) 111, DVD drive 112, video processor 113, memory 113A, card controller 113, wireless LAN controller 114, IEEE 1394 controller 115, embedded controller / keyboard controller IC (EC / KBC) 116 TV tuner 117, EEPROM 118, and the like.

  The CPU 101 is a processor that controls the operation of the computer 10 and executes various application programs such as an operating system (OS) 201 and a TV application program 202 that are loaded from the hard disk drive (HDD) 111 to the main memory 103. . The TV application program 202 is software for executing a TV function. The TV application program 202 includes a live reproduction process for viewing broadcast program data received by the TV tuner 117, a recording process for recording the received broadcast program data in the HDD 111, and broadcast program data / data recorded in the HDD 111. A reproduction process for reproducing video data is executed. The CPU 101 also executes a BIOS (Basic Input Output System) stored in the BIOS-ROM 109. The BIOS is a program for hardware control.

  The north bridge 102 is a bridge device that connects the local bus of the CPU 101 and the south bridge 104. The north bridge 102 also includes a memory controller that controls access to the main memory 103. The north bridge 102 also has a function of executing communication with the GPU 105 via a PCI EXPRESS standard serial bus or the like.

  The GPU 105 is a display controller that controls the LCD 17 used as a display monitor of the computer 10. A display signal generated by the GPU 105 is sent to the LCD 17. The GPU 105 can also send a digital video signal to the external display device 1 via the HDMI control circuit 3 and the HDMI terminal 2.

  The HDMI terminal 2 is the above-described external display connection terminal. The HDMI terminal 2 can send an uncompressed digital video signal and a digital audio signal to the external display device 1 such as a television with a single cable. The HDMI control circuit 3 is an interface for sending a digital video signal to the external display device 1 called an HDMI monitor via the HDMI terminal 2.

  The south bridge 104 controls each device on an LPC (Low Pin Count) bus and each device on a PCI (Peripheral Component Interconnect) bus. The south bridge 104 includes an IDE (Integrated Drive Electronics) controller for controlling the hard disk drive (HDD) 111 and the DVD drive 112. Further, the south bridge 104 has a function of executing communication with the sound controller 106.

  Furthermore, a video processor 113 is connected to the south bridge 104 via a PCI EXPRESS standard serial bus or the like.

  The video processor 113 is a processor that executes various processes related to the above-described video. The memory 113A is used as a working memory for the video processor 113. A large amount of calculation is required to execute detailed processing. In the present embodiment, a video processor 113 which is a dedicated processor different from the CPU 101 is used as a back-end processor, and various kinds of detailed processing are executed by the video processor 113 without causing an increase in the load on the CPU 101. The

  The sound controller 106 is a sound source device, and outputs audio data to be reproduced to the speakers 18A and 18B or the HDMI control circuit 3.

  The wireless LAN controller 114 is a wireless communication device that performs wireless communication of, for example, IEEE 802.11 standard. The IEEE 1394 controller 115 executes communication with an external device via an IEEE 1394 standard serial bus.

  The embedded controller / keyboard controller IC (EC / KBC) 116 is a one-chip microcomputer in which an embedded controller for power management and a keyboard controller for controlling the keyboard (KB) 13 and the touch pad 16 are integrated. . The embedded controller / keyboard controller IC (EC / KBC) 116 has a function of powering on / off the computer 10 in accordance with the operation of the power button 14 by the user. Further, the embedded controller / keyboard controller IC (EC / KBC) 116 has a function of executing communication with the remote control unit interface 20.

  The TV tuner 117 is a receiving device that receives broadcast program data broadcast by a television (TV) broadcast signal, and is connected to the antenna terminal 19. The TV tuner 117 is realized as a digital TV tuner capable of receiving digital broadcast program data such as terrestrial digital TV broadcast. The TV tuner 117 also has a function of capturing video data input from an external device.

  The wireless LAN controller 114 is a so-called Wi-Fi module that searches for a connectable base station and performs wireless LAN communication with the base station, and its operation is controlled by an instruction from the CPU 101. The wireless LAN controller 114 has a function of down-converting a received wireless signal and decoding it to obtain data, and a function of transmitting data (encoding, modulation, wireless transmission).

  When there is a connection request from the user through the input unit, the CPU 101 controls the wireless LAN controller 114 to detect an SSID (Service Set Identifier) of a connectable base station, and an available base station A base station with the best reception status or a user-designated base station is detected and wirelessly connected to start communication.

  The wireless LAN controller 114 receives a beacon transmitted from each base station, decodes each beacon, and detects an SSID (Service Set Identifier) included in the beacon, that is, identification information of the base station. As a result, base stations located around the mobile radio terminal device are detected, and the detection result is notified to the CPU 101.

  Based on the SSID notified from the wireless LAN controller 114, the CPU 101 determines whether there is an available base station (for example, a base station that provides a subscribed service) in the vicinity. Further, the CPU 101 detects the reception timing of the stored SSID based on the SSID received by the wireless LAN controller 114. The wireless LAN controller 114 may not perform a search for the timing of a predetermined period including the reception timing notified from the CPU 101. Thereby, an unnecessary search period by the wireless LAN controller 114 is suppressed, and further power consumption can be reduced.

  The CPU 101 controls the wireless LAN controller 114 to instruct to connect to the available base station. In response to this, the wireless LAN controller 114 performs wireless communication with an available base station according to a predetermined protocol, establishes a communication link, and ends the processing.

FIG. 5 shows a flowchart of the operation of the CPU 71 main body showing the apparatus (system) of the first embodiment. First, select the mode for starting the source device. The manual on mode is a conventional method in which the power is manually turned on, and the automatic on mode is a method in which the power of the source device is automatically turned on and the power is managed depending on the presence or absence of a WFD compatible sink terminal. In the first embodiment 1, the automatic on mode will be described. In the automatic on mode (Yes in step S51), the source device is automatically turned on (step S52). Next, the source device establishes Wi-Fi connection with the AP, and the source device refers to the list of WFD compatible devices (step S53). If a WFD compatible device is included in the list (Yes in step S54), the source device shifts to a WFD standby state (step S57). If the list does not include a WFD compatible device (No in step S54), the source device is turned off (step S55), and after the set time T1 has elapsed since the power was turned off (Yes in step S56). ), The process returns to the process of turning on the source device again (step S52 and subsequent steps). When the source device is in a WFD standby state (step S57), if there is no WFD connection request (No in step S58) and the set time T2 has elapsed (Yes in step S59), a Wi-Fi connection is made with the AP. Returning to the process (step S53 and subsequent steps), if there is a WFD connection request before the set time T2 elapses (Yes in step S58), the process proceeds to a process of starting WFD via P2P or AP ( Step S60).

  FIG. 6 shows a startup sequence of the source device according to the first embodiment. In this example, after the source device is activated, the source device is turned off because no WFD-compatible device exists in the first list reference. After the set period T1, the source device shifts to the WFD standby state when it is assumed that the list includes a WFD-compatible device in the second list reference. If there is a WFD connection request until T2 elapses in this state, the WFD service is started. If there is no WFD connection request during the T2 period, the process proceeds to AP list confirmation processing in the T1 cycle. The above is the description of the first embodiment.

  Next, FIG. 7 shows a flowchart of the operation mainly performed by the CPU 71 showing the apparatus (system) of the first embodiment. First, select the mode for starting the source device. The manual on mode is a conventional method in which the power is manually turned on, and the automatic on mode is a method in which the power of the source device is automatically turned on and the power is managed depending on the presence or absence of WFD. In the first embodiment 2, the automatic on mode will be described. In the automatic on mode (Yes in step S71), the source device is automatically turned on (step S72). Next, the source device establishes Wi-Fi connection with the AP, and the source device refers to the list of WFD compatible devices (step S73). If the list includes a WFD-compatible device (Yes in step S74), the source device shifts to a WFD standby state (step S77). If the list does not include a WFD compatible device (No in step S74), the source device is turned off (step S75), and after the set time T1 has elapsed since the power was turned off (Yes in step S76). ), The process returns to the process of turning on the power of the source device (step S72 and subsequent steps). Processing up to the WFD standby state is the same as in the first embodiment. In the first embodiment 2, when the source device is in the WFD standby state (step S77), if there is no WFD connection request (No in step S78) and the set time T3 has elapsed (Yes in step S79). The power of the source device is turned off (step S80), and after the set time T4 has elapsed since the power was turned off (Yes in step S81), the process returns to the process of turning on the power of the source device again (step S72 and subsequent steps). If there is a WFD connection request when the source device is in the WFD standby state (Yes in step S78), the process proceeds to processing for starting WFD via P2P or AP (step S82).

  FIG. 8 shows a startup sequence of the source device of the first embodiment. After starting the source device, the source device is turned off because there is no WFD-compatible device in the first list reference. After the set time T1, the source device is turned off because no WFD-compatible device exists in the second list reference. After the set time T1, the source device shifts to the WFD standby state, assuming that the list includes a WFD-compatible device in the third list reference. If there is no WFD connection request for the time T3 set in this state and the T3 period has elapsed, the source device is turned off once. After the time T4 has elapsed since the power was turned off, turn the power on again, refer to the list, and if a WFD compatible device is included, shift to the WFD standby state. If there is a WFD connection request, the WFD service will be started. The The above is the description of the first embodiment.

Here, the magnitude relationship between the set times T1, T2, T3, and T4 in the first embodiment is specified. T1 is longer than T4 and T3 is longer to improve responsiveness, but there is a trade-off relationship that increases power consumption.T4 is longer to reduce power consumption, but responsiveness deteriorates. There is a relationship.

<Summary of the first embodiment>
1. The AP monitors the WFD IE (Wi-Fi Display information element) included in the probe request signal from the mobile terminal, identifies the WFD compatible device from the WFD IE, and there is a WFD compatible device in the area of the local station. In this case, the wireless base station apparatus is characterized in that the information is listed.
2. The source device connects to the radio base station at the set cycle T1, refers to a list indicating whether or not a WFD-compatible device exists, and when a WFD-compatible device exists in the radio base station area, A wireless terminal device characterized by turning on the power to provide WFD service was described.

2-1. The wireless terminal device remains in the WFD standby state when there is no access to the WFD, and when the time T2 elapses in the WFD standby state, the wireless terminal device connects to the wireless base station device again, and the wireless base station area When there is no WFD compatible device, the power is turned off.

2-2. The wireless terminal device turns off the power of the wireless terminal device when there is no WFD connection request during a time T3 set from the start of the WFD standby state, and the wireless terminal device after the set time T4 has elapsed The apparatus is turned on, and the process returns to the process of periodically connecting to the radio base station.

  In the first embodiment, compared with the conventional means for always turning on the power of the source terminal, the trouble of turning on the power of the source device can be saved. Furthermore, as an effect of the first embodiment, for example, the power consumption of the source device can be reduced by about 66%. The effect of the first embodiment is that the power consumption of the source device can be reduced by about 81% (the sink terminal is 1 hour in the morning and 5 hours in the evening (of which 1 hour WFD is used), and the Wi-Fi module is assumed to be USB. And estimate power consumption).

  In addition to the assumptions in parentheses above, this effect is calculated by multiplying the power consumption of the USB Wi-Fi module by the time (the power consumption of the USB Wi-Fi module is Value). The values used for the calculation are described below.

  When the Tx power is always on, the Wi-Fi active and WFD using time [H] and their power consumption [Wh] are 22 and 47.4, and 2 and 7.4, respectively. In total, the daily power consumption is about 54.9.

  On the other hand, in the case of Example 1, they are 6 and 12.9, and 2 and 3.1, respectively. On the other hand, the power off time [H] and their power consumption [Wh] are 18 and 2.7. In total, the daily power consumption is about 18.8. This is a 66% reduction from the above 54.9.

  In the case of Example 2, Wi-Fi active and WFD using are 0.33 and 0.7, and 2 and 6.4, respectively. The power off time [H] and their power consumption [Wh] are 21.67 and 3.3. In total, the daily power consumption is approximately 10.4. This is an 81% reduction from the above 54.9.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS. Description of the parts common to the first embodiment is omitted.

<Second Example>
FIG. 9 is a schematic block diagram showing an apparatus (system) of the second embodiment. As in the first embodiment, the second embodiment takes up WFD, which is one of the wireless displays, and uses a sink terminal with an AP function.

  When the source device receives a Beacon signal from Prove Res by Active Scan or AP by Passive Scan, based on the WFD IE, whether the AP is a WFD-compatible device or not, based on the Scan result (Beacon, Probe Response) The terminal has the function of becoming an AP, and additionally has the function of transmitting WFD IE in the Beacon signal to be transmitted. It is characterized by.

  That is, the source device 9 receives video content sent from the video output device 8 through the HDMI interface, and the source device 9 is configured to send the received video content to the sink terminal 10 + 80 with AP function. At this time, the sink terminal 10 + 80 can turn on the source device 9.

  FIG. 10 shows a flowchart of the operation of the CPU 71 as a main component showing the apparatus (system) of the second embodiment. The manual on mode is a conventional method in which the power is manually turned on, and the automatic on mode is a method in which the power of the source device is automatically turned on and the power is managed depending on the presence or absence of WFD. In the second embodiment, the automatic on mode will be described. In the auto-on mode, the source device is automatically turned on. This time, the explanation is based on the premise that it is used in the automatic on mode. In the case of the automatic on mode (Yes in step S101), the source device is automatically turned on (step S102). Next, the source device starts AP Scan (step S103). Here, with regard to AP Scan, in the case of a battery-driven terminal, it is common to operate intermittently in order to reduce power consumption. If the source device receives a Probe Response by Active Scan or a Beacon signal by Passive Scan (Yes in Step S104), and the WFD IE is included in the Prove Response or Beacon signal (Yes in Step S105) The Beacon transmission source is determined to be a WFD compatible device, and the WFD standby state is entered (step S106). In the WFD standby state, if there is a WFD connection request (Yes in step S107), the process proceeds to processing for starting WFD via P2P or AP (step S109), but if there is no WFD connection request (step S107). No) Leave in the WFD standby state. If the time T5 has elapsed from the start of the WFD standby state and no WFD connection request is made during that time (Yes in step S108), the process returns to the Beacon Scan process (step S103 and subsequent steps).

  FIG. 11 shows the activation sequence of the source device of the second embodiment. In this example, Beacon Scan is performed after starting the source device. When the source terminal enters the communication area of the sink terminal with the AP function, the source device determines that WFD IE is included in the Prove Response or Beacon, and shifts to the WFD standby state. If there is no WFD connection request from the start of the WFD standby state until T5 elapses, the process returns to AP Scan processing, and if there is a WFD-compatible device, the process again shifts to the WFD standby state. This is repeated until there is a WFD connection request. When there is a WFD connection request in the WFD standby state, the WFD service is started. The above is the outline of the second embodiment.

<Summary of the second embodiment>
The mobile terminal has a function as an AP, and when operating as an AP, the mobile terminal has a function of transmitting a WFD IE in a Beacon signal to be transmitted. When a source device receives a Beacon signal from an AP, the wireless device determines whether the AP is a WFD-compatible device based on WFD IE based on a scan result (Beacon, Probe Response). The combination of devices 2 has been described.

In addition, this invention is not limited to the said embodiment, In the range which does not deviate from the summary, it can implement in various modifications.

  Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements according to different embodiments may be appropriately combined.

  DESCRIPTION OF SYMBOLS 10 ... Electronic device (computer), 111A ... Database, 113 ... Video processor, 117 ... TV tuner, 403 ... Reproduction processing part.

Claims (5)

Monitoring means for monitoring WFD IE (Wi-Fi Display information element) included in the probe request signal from the sink device, and determining whether or not the mobile terminal is a WFD compatible device from this WFD IE;
A radio base station device comprising: identification means for acquiring identification information of the mobile terminal determined to be the WFD-compatible device and listing the identification information. Reference means for connecting to the radio base station apparatus at the set cycle T1 and referring to a list indicating whether or not a WFD-compatible device exists;
A wireless terminal device comprising power control means for turning on the power so that a WFD service can be provided as a source device when the WFD-compatible device exists in the wireless base station area.   If there is no access to the WFD from the sink device, it remains in the WFD standby state, and when the time T2 has passed in this WFD standby state, it connects to the radio base station device again, and within the area of the radio base station The wireless terminal device according to claim 2, wherein the power is turned off when no WFD compatible device exists.   When there is no WFD connection request during the time T3 set from the start of the WFD standby state, the wireless terminal device is turned off, and after the set time T4 has elapsed, the wireless terminal device is turned on. The wireless terminal device according to claim 2, returning to the process of periodically connecting to the wireless base station. A sink device that has the function of an AP and when it operates as an AP, adds a WFD IE to the Beacon signal to be transmitted, and
A wireless transmission system comprising a source device that, when receiving a Beacon signal from an AP, determines whether the AP is a WFD-compatible device based on WFD IE based on a Scan result of Beacon or Probe Response.

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