TWI815036B - Information terminal and intercom system - Google Patents

Abstract

An object of the present invention is to provide a technology that can stably transmit information even if the situation changes. The residential information screen 400 can be installed in the facility. The home information panel 400 includes a control unit 440, a first communication unit 450, and a second communication unit 460. The first communication unit 450 is connected to the entrance device and communicates with the entrance device. The second communication unit 460 is connected to the communication device and communicates with the communication device. The control unit 440 controls the second communication unit 460. The control unit 440 selects multicast or unicast to cause the second communication unit 460 to transmit information.

Description

Information terminal and intercom system

The present invention relates to a communication technology, and in particular to an information terminal and an intercom system for transmitting information.

The intercom system includes a door phone with a camera and an intercom master with a surveillance TV. When the call button is pressed on the door phone, the video captured by the door phone will be displayed on the surveillance TV of the door phone. image (for example, refer to Patent Document 1). [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Laid-Open No. 2012-15974

[Problem to be solved by the invention]

When the intercom system is installed in a collective facility such as a building, the entrance device is installed at the entrance of the collective facility, and a residential information screen is installed in a facility in the collective facility, such as a house, to implement the interaction between the entrance device and the residential information screen. call between guests. Furthermore, by connecting the auxiliary device installed in the facility to the home information panel, the auxiliary device can perform incoming calls between the home information panel and the entrance device. Before executing the guest call, the call request that triggers the start of the guest call is sent to the home information screen and the auxiliary device together with the image signal of the visitor captured in the entrance device. If the number of secondary devices increases, the transmission frequency band used to send image signals may increase. Is it possible to ensure that the transmission frequency band as mentioned above changes with the situation. Therefore, it is desired to reliably transmit image signals to a plurality of secondary devices even if the situation changes.

The present invention was made in view of this situation, and its purpose is to provide a technology that can stably transmit information even if the situation changes. [Technical means to solve problems]

In order to solve the above problem, an information terminal of a certain form of the present invention can be installed in a facility and includes: a first communication unit that communicates with the entrance device; a second communication unit that communicates with the communication device; and a control unit. , which controls the 2nd Communications Department. The control unit selects multicast or unicast and causes the second communication unit to transmit information.

Furthermore, any combination of the above constituent elements, and any transformation of the expression of the present invention into methods, devices, systems, recording media, computer programs, etc. are also effective as forms of the present invention. [Effects of the invention]

According to the present invention, information can be sent stably even if the situation changes.

(Example 1) Before describing the present invention in detail, an outline will be described. The embodiment relates to an intercom system installed in collective facilities such as buildings and public residences. Collective facilities contain multiple housing and other facilities, and have at least one public entrance for people to enter and exit. Visitors operate the entrance devices such as the lobby intercom installed at the public entrance to call the residential information screen installed at the visited facility. Residents of the facility respond to calls and operate the home information screens to identify visitors. If the resident operates the home information panel to respond to the call, the guest call between the entrance device and the home information panel is performed.

Furthermore, in a facility, a sub-device may be installed in a room different from the room where the home information screen is installed. The auxiliary device communicates with the home information panel, and performs a guest call with the entrance device via the home information panel. Furthermore, facilities may sometimes be equipped with routers for accessing the Internet. Terminal devices such as smartphones, tablets, and PCs (Personal Computers) are connected to the Internet through routers. When the home information panel is connected to the router, communication can be performed between the home information panel and the terminal device via the router. Therefore, the terminal device performs a guest call with the entrance device via the home information screen.

In order to perform an incoming call on any one of the home information panel, the sub-device, and the terminal device, the call request from the entrance device must be sent not only to the home information panel but also from the home information panel to the sub-device and the terminal device. In addition, the sound signal and video signal acquired in the entrance device are also sent to the home information panel, auxiliary device, and terminal device together with the call request. Furthermore, when there are a plurality of slave devices or terminal devices, the call request, audio signal, and video signal are sent to all of the plurality of slave devices or terminal devices. When the resident responds to such a call request using any one of the home information panel, the auxiliary device, and the terminal device, for example, one auxiliary device, an incoming call is made between the one auxiliary device and the entrance device. Hereinafter, a plurality of slave devices and a plurality of terminal devices are collectively referred to as "a plurality of communication devices". The plurality of communication devices may include only a plurality of slave devices, a plurality of terminal devices, or may include one or more slave devices and one or more terminal devices.

Before the incoming call starts, video signals are sent to multiple communication devices. However, after the incoming call starts, the video signal is sent to, for example, one secondary device. Therefore, compared with after the incoming call starts, a wider period of time is required before the incoming call starts. transmission band. In addition, when a plurality of communication devices are connected to a home information panel through wireless communication, whether or not the transmission band required before the start of the incoming call can be secured in wireless communication changes depending on various situations. For example, if the communication environment during wireless communication deteriorates, it will be difficult to secure the above-mentioned transmission band. If the communication environment during wireless communication improves, it will be easier to secure the above-mentioned transmission band. Furthermore, if the number of secondary devices and terminal devices that perform wireless communication increases, it is difficult to secure the above-mentioned transmission band. If the number of secondary devices and terminal devices that perform wireless communication decreases, it becomes easier to secure the above-mentioned transmission band. Therefore, it is desired to reliably transmit the image signal before the call starts to a plurality of communication devices even when the situation changes.

The intercom system of this embodiment switches between multicast and unicast according to the situation. In the case of multicast, the video signal is sent uniformly to a plurality of communication devices, and in the case of unicast, the video signal is sent to each of the plurality of communication devices. Therefore, the transmission band used in multicast may be smaller than that used in unicast. Therefore, even in a situation where the transmission band for transmitting the video signal cannot be secured in the case of unicast, the transmission band for transmitting the video signal can be secured in the case of multicast.

1(a)-(b) show the structure of the intercom system 1000. In FIG. 1(a) , the collective facility 100 includes a first facility 110a, a second facility 110b, and a third facility 110c collectively referred to as facilities 110. The intercom system 1000 includes an entrance device 200, a control device 300, a common trunk line 310, an occupied trunk line 320, a home information panel 400, a relay device 500, and a first auxiliary device 600a, a second auxiliary device 600b, which are collectively referred to as the auxiliary devices 600. Router 700, network 710, server 720, terminal device 800 and entrance slave 850. The number of facilities 110 in the collective facility 100 is not limited to "3", the number of auxiliary devices 600 is not limited to "2", and the number of terminal devices 800 is not limited to "1". The home information panel 400, the relay device 500, the secondary device 600, the router 700, and the terminal device 800 are shown only in the first facility 110a, but are also included in the second facility 110b and the third facility 110c. When the home information panel 400 is called an information terminal, the secondary device 600 and the terminal device 800 are called communication devices.

The intercom system 1000 includes: a main line system, which includes the entrance device 200, a control device 300, and a home information screen 400; and an extension system, which includes a home information screen 400, a secondary device 600, and a terminal device 800. The intercom system 1000 can perform incoming call processing, which is a call using sound and image between any one of the home information panel 400, the secondary device 600, the terminal device 800, and the entrance device 200. The following is as follows: (1) Incoming call processing in the trunk system, (2) Incoming call processing including the secondary device 600, (3) Incoming call processing including the terminal device 800, (4) Switching control processing between multicast and unicast explained in order.

(1) Incoming call processing in trunk system In the collective facility 100, a plurality of facilities 110 are concentrated. One example of the collective facilities 100 is a building, and one example of the facilities 110 is a house. The entrance device 200 is installed at the public entrance of the collective facility 100 . The entrance device 200 is, for example, a lobby intercom installed in a lobby of a building. 2(a)-(c) show the structure of the entrance device 200, the home information screen 400, and the auxiliary device 600. FIG. 2(a) shows the structure of the entrance device 200. The entrance device 200 includes a processing unit 210, an operation unit 230, a control unit 240, and a communication unit 250. The processing unit 210 includes a camera unit 212, a microphone 214, a speaker 216, a monitor 218, and an IF (Interface) unit 220.

The operation unit 230 of the entrance device 200 is a user interface for accepting operations from visitors, such as a call button. When the operation unit 230 receives the number of the facility 110 scheduled to be visited from the visitor, it outputs a call request to the control unit 240 . In addition, when the visitor operates the operation unit 230, the processing unit 210 operates.

The imaging unit 212 is equipped with solid-state imaging elements such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor and a CCD (Charge Coupled Device) image sensor to photograph visitors. The solid-state imaging element outputs an image signal obtained by photoelectric conversion to the IF unit 220 . The IF unit 220 performs various signal processing on the image signal from the imaging unit 212 . As long as the various signal processing uses well-known techniques, descriptions thereof are omitted here. The IF unit 220 outputs an image signal (hereinafter, also referred to as an “image signal”) obtained by performing signal processing to the control unit 240 .

The microphone 214 and the speaker 216 are user interfaces for visitors to communicate with residents. The microphone 214 collects the visitor's voice, converts it into an electrical signal, and outputs it to the IF unit 220 . The IF unit 220 receives the electrical signal from the microphone 214 and converts it into a signal in a form for transmission (hereinafter referred to as "sound signal"). The IF unit 220 outputs the sound signal to the control unit 240 . On the other hand, the IF unit 220 inputs an audio signal from the control unit 240 and converts the audio signal into an electrical signal. IF section 220 outputs an electrical signal to speaker 216 . The speaker 216 regenerates the electrical signal from the IF unit 220 and outputs sound.

The monitor 218 displays messages and the like. The IF unit 220 inputs a message signal from the control unit 240 and outputs the message signal to the monitor 218 . The message signal can also be generated in the entrance device 200. The control unit 240 controls the operation of the entrance device 200. The control unit 240 is connected to the communication unit 250 . The communication unit 250 is connected to the control device 300 via the common unit trunk line 310, and communicates with the home information panel 400 via the control device 300. To explain specifically, the communication unit 250 sends a call request and video signals to the home information panel 400, and transmits and receives audio signals and message signals to and from the home information panel 400. However, the signals are not limited to these. Figures 2(b)-(c) will be described below and return to Figure 1(a).

The control device 300 is installed in a shared space such as a mechanical room or a manager's room, and relays signals between the entrance device 200 and the home information screen 400 . At this time, the control device 300 extracts the transmission destination information included in the signal from the entrance device 200, and transmits the signal to the home information panel 400 of the transmission destination indicated in the extracted information. The shared trunk line 310 and the occupied trunk line 320 are transmission paths used to transmit call requests from the entrance device 200, response signals from the home information panel 400, etc., and are, for example, dedicated lines. The above-mentioned call request, video signal, voice signal, and message signal are transmitted on the shared trunk line 310 and the occupied trunk line 320.

The home information screen 400 is installed in the facility 110 and is also called a resident unit, a resident terminal, a living room base unit, and a home base unit. FIG. 2(b) shows the structure of the home information screen 400. The home information panel 400 includes a processing unit 410, an operation unit 430, a control unit 440, a first communication unit 450, and a second communication unit 460. The processing unit 410 includes a microphone 414, a speaker 416, a monitor 418, and an IF unit 420.

The first communication unit 450 is connected to the control device 300 via the possession trunk line 320, and communicates with the entrance device 200 via the control device 300. The control unit 440 is connected to the first communication unit 450, and the control unit 440 controls the operation of the home information panel 400. The control unit 440 is connected to the IF unit 420 and the operation unit 430 , and the IF unit 420 is connected to the microphone 414 , the speaker 416 , and the monitor 418 . Here, the microphone 414, the speaker 416, the IF unit 420, and the operation unit 430 are configured similarly to the microphone 214, the speaker 216, the IF unit 220, and the operation unit 230. The monitor 418 displays the image captured by the camera unit 212 of the entrance device 200 .

The control unit 440 receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450 . When the control unit 440 accepts the call request, the control unit 440 causes the call sound to be output from the speaker 416 via the IF unit 420 . Then, the control unit 440 displays the image obtained by reproducing the video signal on the monitor 418 via the IF unit 420 , and outputs the sound obtained by reproducing the audio signal from the speaker 416 via the IF unit 420 . When the resident who hears the call tone responds to the call by operating the operation unit 430, the control unit 440 causes the first communication unit 450 to communicate with the entrance device 200. As a result, an image signal is sent from the communication unit 250 to the first communication unit 450, and an audio signal is transmitted between the communication unit 250 and the first communication unit 450. Thereby, the visitor who operates the entrance device 200 and the visitor who operates the home information screen can communicate with each other. Calls between 400 residents can be carried out. Figure 2(c) will be described below, returning to Figure 1(a).

(2) Incoming call processing including secondary device 600 The relay device 500 has a communication function corresponding to a wireless communication system such as a wireless LAN (Local Area Network), and relays signals between the home information panel 400 and the auxiliary device 600 included in the extension system. The relay device 500 is, for example, an AP (Access Point) mode router. In AP mode router, the wireless communication function is enabled but the router function is disabled. The auxiliary device 600 is also called an auxiliary master machine or a auxiliary master machine with a monitor, and can handle incoming calls with the entrance device 200 through the home information screen 400 .

FIG. 2(c) shows the structure of the secondary device 600. The secondary device 600 includes a processing unit 610, an operation unit 630, a control unit 640, and a communication unit 650. The processing unit 610 includes a microphone 614, a speaker 616, a monitor 618, and an IF unit 620. The microphone 614, the speaker 616, the monitor 618, the IF unit 620, and the operation unit 630 are configured similarly to the microphone 414, the speaker 416, the monitor 418, the IF unit 420, and the operation unit 430. The communication unit 650 has the same communication function corresponding to the wireless communication system as the relay device 500 . The communication unit 650 performs communication with the entrance device 200 via the relay device 500, the home information panel 400, and the control device 300 during incoming call processing. The control unit 640 is connected to the communication unit 650, and the control unit 640 controls the operation of the secondary device 600.

As described above, the control unit 440 of the home information panel 400 in FIG. 2(b) receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450. The control unit 440 sends the call request, video signal, and audio signal from the second communication unit 460 . The call request, video signal, and audio signal transmitted from the second communication unit 460 are received by the first secondary device 600a and the second secondary device 600b via the relay device 500 in FIG. 1(a).

The communication unit 650 of the secondary device 600 in FIG. 2(c) receives a call request, an image signal, and an audio signal. When the communication unit 650 receives the call request, the control unit 640 causes the call sound to be output from the speaker 616 via the IF unit 620 . When the communication unit 650 receives the video signal and the audio signal, the control unit 640 displays the image obtained by reproducing the video signal on the monitor 618 via the IF unit 620 , and outputs the sound obtained by reproducing the audio signal from the speaker 616 via the IF unit 620 . When the resident who hears the call tone responds to the call by operating the operation unit 630, the control unit 640 notifies the home information panel 400 of the response via the communication unit 650, thereby causing the communication unit 650 to execute the communication with the entrance device 200. communication between. As a result, the video signal is transmitted from the communication unit 250 to the communication unit 650 via the home information panel 400 and the relay device 500 . Furthermore, the voice signal is transmitted between the communication unit 250 and the communication unit 650 via the home information panel 400 and the relay device 500 . By this, communication between the visitor who operates the entrance device 200 and the resident who operates the sub-device 600 is performed. Return to Figure 1(a).

(3) Incoming call processing including terminal device 800 The router 700 is a device for connecting the network in the first facility 110a to the external network 710 of the first facility 110a. The network 710 includes the Internet, and the server 720 is a device that performs specific processing on the Internet. The terminal device 800 is a communication device such as a smartphone, tablet, or PC. The terminal device 800 communicates with the server 720 via the network 710 by being connected to the router 700 or the relay device 500 in the first facility 110a. Furthermore, the terminal device 800 communicates with the server 720 by connecting to the network 710 outside the first facility 110a. Furthermore, by connecting to the home information panel 400 via the router 700 or the relay device 500, the terminal device 800 can execute the guest call processing with the entrance device 200 via the home information panel 400.

As described above, the control unit 440 of the home information panel 400 in FIG. 2(b) receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450. The control unit 440 sends the call request, video signal, and audio signal from the second communication unit 460 . The call request, video signal, and audio signal transmitted from the second communication unit 460 are received by the terminal device 800 via the relay device 500 and the router 700 in FIG. 1(a) .

The terminal device 800 has the same configuration as in FIG. 2(c) and outputs a call tone when receiving a call request. When the terminal device 800 receives a video signal and an audio signal, it displays an image obtained by reproducing the video signal, and outputs a sound obtained by reproducing the audio signal. When the resident who hears the call tone responds to the call by operating the terminal device 800, the terminal device 800 communicates with the entrance device 200 by notifying the response to the home information panel 400. As a result, the communication unit 250 transmits a video signal to the terminal device 800 via the home information panel 400, the relay device 500, and the router 700. Furthermore, the voice signal is transmitted between the communication unit 250 and the terminal device 800 via the home information panel 400, the relay device 500, and the router 700. By this, communication between the visitor operating the entrance device 200 and the resident operating the terminal device 800 is performed.

In this way, the communication devices that can communicate with the second communication unit 460 of the home information panel 400 include the terminal device 800 that communicates via the router 700 and the secondary device 600 that does not communicate via the router 700 . Here, when the terminal device 800 is called a first type communication device, the secondary device 600 is called a second type communication device.

(4) Multicast and unicast switching control processing The following description will focus on the transmission of video signals before the incoming call starts. The image signal is a signal sent together with the call request. Particular attention is paid to the image signals sent from the home information screen 400 to a plurality of communication devices via the relay device 500. As mentioned above, the plurality of communication devices are collectively referred to as the plurality of secondary devices 600 and the plurality of terminal devices 800 . Before an incoming call starts, all communication devices must display an image including the visitor by receiving image signals. The transmission of video signals requires a wider transmission band than the transmission of sound signals. Therefore, depending on the conditions in a plurality of communication devices, there is a risk that the video signal may not be received correctly by a plurality of communication devices. As a result, the quality of images displayed on multiple communication devices may deteriorate.

In order to reliably send the video signal before the call starts to a plurality of communication devices, the second communication unit 460 of the home information panel 400 in FIG. 2(b) can implement two methods: multicast and unicast. In addition, before the incoming call starts, the control unit 440 selects multicast or unicast and causes the second communication unit 460 to transmit the video signal. At this time, the call request and voice signal are also sent in the same manner.

Here, unicast refers to a method in which the second communication unit 460 communicates with a communication device on a one-to-one basis, and selects a communication speed suitable for each communication device from a plurality of communication speeds specified in the wireless communication system. Furthermore, since the communication speed suitable for each communication device is selected, the communication speed of each communication device can be set to high speed. In this type of unicast, the speed of the image signal, that is, the quality of the image, can be changed for each communication device by applying the measurement results of the communication status of the wireless communication to each communication device. On the other hand, since the image signal is sent to each communication device, if the number of communication devices increases, the transmission frequency band used to transmit the image signal will also become wider. In this situation, if an error occurs in the communication of the image signal in any communication device, the image signal will be retransmitted. Therefore, the transmission band used by the communication device becomes wider. If the transmission band becomes wider, the transmission band for transmitting image signals to other communication devices is likely to be insufficient, thus affecting other communication devices.

Multicast refers to a method in which the second communication unit 460 performs one-to-many communication with a plurality of communication devices, and selects the lowest communication speed among a plurality of communication speeds. Therefore, the communication speed of each communication device in multicast is lower than the communication speed of each communication device in unicast. On the other hand, since the image signal system is sent to a plurality of communication devices, even if the number of communication devices increases, the transmission frequency band used to send the image signal does not change. In addition, retransmission control is not performed in multicast, so even if an error occurs in the communication of the image signal in any one communication device, it will not affect other communication devices.

The selection of multicast or unicast in the control unit 440 is performed, for example, in any one of the first to third methods. (A) 1st method The control unit 440 in FIG. 2(b) measures the magnitude of the interference power (hereinafter referred to as "interference amount") for the second communication unit 460. The amount of interference can be measured using known techniques, and the amount of interference is equivalent to the size of a signal that has been transmitted by other devices in a communication environment in which the second communication unit 460 transmits an image signal or the like. Therefore, the smaller the amount of interference, the easier it is to secure a transmission band for transmitting image signals. The larger the amount of interference, the harder it is to secure a transmission band for transmitting image signals.

3(a)-(b) show the data structure of the table used in the control unit 440. As shown in FIG. 3(a) , the control unit 440 selects multicast when the amount of interference is equal to or greater than the threshold, and selects unicast when the amount of interference is less than the threshold. The threshold is set based on the boundary value of the transmission band that can be secured through unicast. The threshold value may be obtained by simulation calculation, for example. Fig. 3(b) will be described below, and return to Fig. 2(b). In this way, the control unit 440 selects multicast or unicast according to the communication environment. The selection process in the control unit 440 is performed periodically, for example.

(B) 2nd method The control unit 440 acquires the number of communication devices connected to the second communication unit 460 . The smaller the number of communication devices, the easier it is to secure a transmission band for transmitting video signals through unicast. The larger the number of communication devices, the more difficult it is to secure a transmission band for transmitting video signals through unicast. As shown in FIG. 3(b) , the control unit 440 selects multicast when the number of communication devices is equal to or greater than the threshold, and selects unicast when the number of communication devices is less than the threshold. The threshold is set based on the number of stations that can secure the boundary of the transmission band through unicast. The threshold value may be obtained by simulation calculation, for example. Return to Figure 2(b). In this way, the control unit 440 selects multicast or unicast according to the number of communication devices connected to the second communication unit 460 .

(C) 3rd method The operation unit 430 accepts instructions for selecting multicast or unicast from the residents. The operation unit 430 outputs the accepted selection instruction to the control unit 440 . The control unit 440 selects multicast or unicast based on the selection instruction from the operation unit 430 .

After selecting any one of the first to third methods, when the second communication unit 460 has acquired the video signal before the start of the incoming call from the first communication unit 450, if the control unit 440 selects unicast, each communication unit The communication speed of the device is to send image signals at the first communication speed. Here, the first communication speed may be a common value for all communication devices, or may be a different value for each communication device. On the other hand, when the second communication unit 460 has acquired the video signal before the start of the incoming call from the first communication unit 450, if the control unit 440 selects multicast, the communication speed of each communication device is transmitted at the second communication speed. image signal. The second communication speed is the lowest communication speed among a plurality of communication speeds, and is a lower communication speed than the first communication speed.

When the first communication unit 450 has acquired the image signal of the moving image information due to the difference between the first communication speed and the second communication speed, the image signal of the moving image information is also transmitted in the unicast, but in the multicast to send image signals of static image information or continuous static image information. Here, the transmission band of the image signal of the moving image information transmitted in the unicast is set to be lower than the transmission band of the image signal of the moving image information acquired by the first communication unit 450 . The transmission frequency band in the second communication part 460 may also be wider than the transmission frequency band in the first communication part 450. In addition, conversion from an image signal as moving image information to an image signal as still image information or continuous still image information is performed in the control unit 440 . This conversion only requires the use of publicly known techniques, and therefore the description is omitted here.

FIG. 1(b) is a configuration in which the relay device 500 is omitted from the configuration in FIG. 1(a). Therefore, the home information panel 400, the first auxiliary device 600a, and the second auxiliary device 600b are connected to the router 700 in the same manner as the terminal device 800. The processing of the intercom system 1000 in FIG. 1(b) is the same as the processing of the intercom system 1000 in FIG. 1(a), so the description is omitted here.

The main body of the device, system or method in the present invention includes a computer. By executing the program on the computer, the functions of the main body of the device, system or method in the present invention are realized. A computer has a processor that acts according to a program as its main hardware component. There is no limit to the type of processor as long as it can implement functions by executing programs. The processor includes one or a plurality of electronic circuits including a semiconductor integrated circuit (IC) or LSI (Large Scale Integration). A plurality of electronic circuits can be integrated into one chip, or can be provided on a plurality of chips. Multiple chips can be integrated into one device or installed in multiple devices. Programs are recorded on non-transitory recording media such as computer-readable ROM (Read Only Memory), optical disks, and hard disks. The program can be stored in the recording medium in advance, or can be provided to the recording medium via a wide area communication network including the Internet.

The operation of the intercom system 1000 constructed as above will be described. 4(a)-(b) are sequence diagrams showing communication steps performed by the intercom system 1000. Figure 4(a) shows the processing when multicast is used. The home information panel 400 receives the call request (S10). A SIP (Session Initiation Protocol) call is established between the home information panel 400 and the first secondary device 600a (S12). A SIP call is established between the home information panel 400 and the second secondary device 600b (S14). The home information screen 400 multicasts the video signal to the first secondary device 600a and the second secondary device 600b (S16, S18). At this point, not only the video signal but also the audio signal can be sent in a multicast manner. The sound signal is the sound from the entrance device 200, such as the sound of a visitor calling (one-way only). The first secondary device 600a displays an image (S20), and the second secondary device 600b displays an image (S22). The first secondary device 600a responds to the call (S24). A SIP call is established between the home information screen 400 and the first secondary device 600a (S26), and the audio signal is unicast between the home information screen 400 and the first secondary device 600a (S28). Thereafter, the home information panel 400 may also perform processing for ending the call processing to the second secondary device 600b.

Figure 4(b) shows the processing when unicast is used. The home information panel 400 receives the call request (S50). A SIP call is established between the home information panel 400 and the first secondary device 600a (S52). The home information screen 400 transmits the video signal to the first secondary device 600a in a unicast manner (S54). A SIP call is established between the home information panel 400 and the second secondary device 600b (S56). The home information screen 400 sends the video signal to the second secondary device 600b in a unicast manner (S58). It is also possible to send not only video signals but also audio signals in a unicast manner at the time points of steps 54 and 58. The sound signal is the sound from the entrance device 200, such as the sound of a visitor calling (one-way only). The first secondary device 600a displays an image (S60), and the second secondary device 600b displays an image (S62). The first secondary device 600a responds to the call (S64). A SIP call is established between the home information screen 400 and the first secondary device 600a (S66), and the audio signal is unicast between the home information screen 400 and the first secondary device 600a (S68).

5(a)-(c) are flowcharts showing the selection procedures performed by the control unit 440. Fig. 5(a) shows the control of the first mode. The second communication unit 460 measures the amount of interference (S100). When the amount of interference is equal to or greater than the threshold (Yes (Y) in S102), the control unit 440 determines transmission in the multicast method (S104). When the amount of interference is not above the threshold (No (N) in S102), the control unit 440 determines unicast transmission (S106).

Fig. 5(b) shows the control of the second mode. When the number of communication devices is greater than the threshold (Y in S150), the control unit 440 determines multicast transmission (S152). When the number of communication devices is not greater than the threshold (N in S150), the control unit 440 determines unicast transmission (S154).

Fig. 5(c) shows the control of the third mode. The operation unit 430 accepts input of settings (S200). When setting up multicast (Y in S202), the control unit 440 determines the multicast transmission method (S204). When the multicast setting is not performed (N in S202), the control unit 440 determines transmission in unicast mode (S206).

FIG. 6 is a flowchart showing the transmission procedure performed by the second communication unit 460. When the control unit 440 selects multicast (Y in S250), the second communication unit 460 sends the still image information as the video signal (S252). When the control unit 440 does not select multicast (N in S250), the second communication unit 460 sends the moving image information as the video signal (S254).

According to this embodiment, multicast or unicast is selected to cause the second communication unit 460 to transmit the video signal. Therefore, even if the situation changes, the video signal can be stably transmitted. In addition, the communication speed per communication device in multicast is lower than the communication speed per communication device in unicast. Therefore, the expansion of the transmission band in multicast can be suppressed. Furthermore, when unicast is selected, the video signal is transmitted at the first communication speed, and when multicast is selected, the video signal is transmitted at the second communication speed, which is lower than the first communication speed. Therefore, communication in multicast is possible. The speed is lower than the communication speed in unicast. In addition, moving image information is sent when unicast is selected, and static image information or continuous static image information is sent when multicast is selected. Therefore, the communication speed in multicast can be lower than that in unicast. the communication speed. In addition, multicast or unicast is selected based on input from the outside, so the desired operation can be performed.

In addition, multicast or unicast is selected according to the communication environment. Therefore, multicast can be selected in a situation where it is difficult to secure a transmission band. In addition, multicast is selected when it is difficult to secure a transmission band, so video signals can be transmitted stably. In addition, multicast or unicast is selected according to the communication environment. Therefore, unicast can be selected in a situation where the transmission band can be easily secured. In addition, unicast is selected when it is easy to secure a transmission band, so video signals can be transmitted with high quality. In addition, multicast or unicast is automatically selected, so no user setting operation is required, and image degradation can be suppressed.

In addition, multicast or unicast is selected according to the number of connected communication devices. Therefore, multicast can be selected when the number of communication devices is large. In addition, multicast is selected when the number of communication devices is large, so that image signals can be transmitted stably. In addition, multicast or unicast is selected according to the number of connected communication devices. Therefore, unicast can be selected when the number of communication devices is small. Furthermore, since unicast is selected when the number of communication devices is small, video signals can be transmitted with high quality. In addition, multicast or unicast is automatically selected, so no user setting operation is required, no communication environment measurement is required, and image deterioration can be suppressed. Furthermore, since it includes a first communication device that communicates via the router 700 and a second communication device that does not communicate via the router 700, the degree of freedom in the configuration can be increased.

An outline of one aspect of the present invention is as follows. A certain form of the home information screen (400) of the present invention is a home information screen (400) that can be installed in a facility (110), and is provided with: a first communication unit (450) that communicates with the entrance device (200); 2. A communication unit (460) that communicates with the secondary device (600) and the terminal device (800); and a control unit (440) that controls the second communication unit (460). The control unit (440) selects multicast or unicast and causes the second communication unit (460) to transmit information.

The communication speed per slave device (600) and terminal device (800) in multicast is lower than the communication speed per slave device (600) and terminal device (800) in unicast.

When the second communication unit (460) has acquired specific information from the first communication unit (450), if the control unit (440) selects unicast, each secondary device (600) and terminal device (800) The communication speed is the first communication speed to send information corresponding to specific information. If the control unit (440) selects multicast, the communication speed of each slave device (600) and terminal device (800) is lower than the first communication speed. The second communication speed of communication speed transmits information corresponding to specific information.

The second communication unit (460) may also transmit the moving image information if the control unit (440) selects unicast when it has acquired the moving image information from the first communication unit (450). If the control unit (440) selects multicast, the second communication unit (460) may Broadcasting sends static image information or continuous static image information.

The control unit (440) may also select multicast or unicast based on input from the outside.

The control unit (440) may also select multicast or unicast according to the communication environment.

The control unit (440) may also select multicast or unicast according to the number of slave devices (600) and terminal devices (800) connected to the second communication unit (460).

The communication device capable of communicating with the second communication unit (460) may include a terminal device (800) that communicates via the router (700), and a secondary device (600) that communicates without via the router (700).

It may also include a residential information screen (400) and a doorway device (200) that communicates with the residential information screen (400).

(Example 2) Before describing the present invention in detail, an outline will be described. When the intercom system is installed in a collective facility such as a building, the entrance device is installed at the entrance of the collective facility, and a residential information screen is installed in a facility in the collective facility, such as a house, to implement the interaction between the entrance device and the residential information screen. call between guests. Furthermore, by connecting the auxiliary device installed in the facility to the home information panel, the auxiliary device can perform incoming calls between the home information panel and the entrance device. Furthermore, by connecting a terminal device such as a smartphone to the home information screen, the terminal device can also perform an incoming call between the home information screen and the entrance device. Before executing the guest call, the call request that triggers the start of the guest call is sent to the home information screen, secondary device, and terminal device together with the image signal of the visitor captured in the entrance device. When the number of auxiliary devices and terminal devices connected to the home information panel through wireless communication increases, in order to improve the reliability of transmitting video signals, etc., it is ideal to use unicast, but for the transmission of video signals, etc. The frequency band will increase.

The present invention was made in view of this situation, and an object thereof is to provide a technology that improves the reliability of transmitted information and suppresses an increase in the transmission band when transmitting information to a plurality of communication devices.

This embodiment relates to an intercom system installed in collective facilities such as buildings and public residences. Collective facilities contain multiple housing and other facilities, and have at least one public entrance for people to enter and exit. Visitors operate the entrance devices such as the lobby intercom installed at the public entrance to call the residential information screen installed at the visited facility. Residents of the facility respond to calls and operate the home information screens to identify visitors. If the resident operates the home information panel to respond to the call, the guest call between the entrance device and the home information panel is performed.

Furthermore, in a facility, a sub-device may be installed in a room different from the room where the home information screen is installed. The auxiliary device communicates with the home information panel, and performs a guest call with the entrance device via the home information panel. Furthermore, facilities may sometimes be equipped with routers for accessing the Internet. Terminal devices such as smartphones, tablets, and PCs are connected to the Internet through routers. When the home information panel is connected to the router, communication can be performed between the home information panel and the terminal device via the router. Therefore, the terminal device performs a guest call with the entrance device via the home information screen.

In order to perform an incoming call on any one of the home information panel, the sub-device, and the terminal device, the call request from the entrance device must be sent not only to the home information panel but also from the home information panel to the sub-device and the terminal device. In addition, the sound signal and video signal acquired in the entrance device are also sent to the home information panel, auxiliary device, and terminal device together with the call request. Furthermore, when there are a plurality of slave devices or terminal devices, the call request, audio signal, and video signal are sent to all of the plurality of slave devices or terminal devices. When the resident responds to such a call request using any one of the home information panel, the sub-device, and the terminal device, for example, a sub-device, an incoming call is made between the sub-device and the entrance device. . Hereinafter, a plurality of slave devices and a plurality of terminal devices are collectively referred to as "a plurality of communication devices". The plurality of communication devices may include only a plurality of slave devices, a plurality of terminal devices, or may include one or more slave devices and one or more terminal devices.

Before the incoming call starts, video signals are sent to multiple communication devices, but after the incoming call starts, the video signal is sent to, for example, one secondary device. Therefore, compared with after the incoming call starts, a wider window is required before the incoming call starts. the transmission band. In addition, depending on the communication conditions of the network connected to the home information screen and multiple communication devices, there may be adverse effects such as unclear images or sounds of visitors, or failure of video signals to reach the communication devices. Alternatively, if video signals, etc. are transmitted in a unicast manner in order to improve the reliability of transmitting video signals, etc., the transmission frequency band will also increase corresponding to the increase in the number of communication devices, which may cause damage to other devices connected to the network. cause impact. Therefore, there is a demand for improving the reliability of transmitting video signals and the like and suppressing an increase in the transmission band.

The intercom system of this embodiment classifies a plurality of communication devices into two groups, for example. The residential information screen sends video signals, etc. in a unicast manner to the communication devices included in the first group of the two groups. On the other hand, the home information panel multicasts video signals and the like to the communication devices included in the second group of the two groups. By performing unicast on the communication devices included in the first group, the reliability of transmitting video signals and the like is improved, and by performing multicast on the communication devices included in the first group, the increase in the transmission band is suppressed.

7(a)-(b) show the structure of the intercom system 1000. In FIG. 7(a) , the collective facility 100 includes a first facility 110a, a second facility 110b, and a third facility 110c collectively referred to as facilities 110. The intercom system 1000 includes an entrance device 200, a control device 300, a common trunk line 310, an occupied trunk line 320, a home information panel 400, a relay device 500, and a first auxiliary device 600a, a second auxiliary device 600b, which are collectively referred to as the auxiliary devices 600. The router 700, the network 710, the server 720, the first terminal device 800a, the second terminal device 800b and the entrance slave machine 850 are collectively referred to as the terminal devices 800. The number of facilities 110 in the collective facility 100 is not limited to "3", the number of auxiliary devices 600 is not limited to "2", and the number of terminal devices 800 is not limited to "2". The home information panel 400, the relay device 500, the secondary device 600, the router 700, and the terminal device 800 are shown only in the first facility 110a, but are also included in the second facility 110b and the third facility 110c. When the home information panel 400 is called an information terminal, the secondary device 600 and the terminal device 800 are called communication devices.

The intercom system 1000 includes: a main line system, which includes the entrance device 200, a control device 300, and a home information screen 400; and an extension system, which includes a home information screen 400, a secondary device 600, and a terminal device 800. The intercom system 1000 can perform incoming call processing, which is a call using sound and image between any one of the home information panel 400, the secondary device 600, the terminal device 800, and the entrance device 200. In the following, description will be given in the order of (1) incoming call processing in the trunk system, (2) incoming call processing including the slave device 600, (3) incoming call processing including the terminal device 800, and (4) group control.

(1) Incoming call processing in trunk system In the collective facility 100, a plurality of facilities 110 are concentrated. One example of the collective facilities 100 is a building, and one example of the facilities 110 is a house. The entrance device 200 is installed at the public entrance of the collective facility 100 . The entrance device 200 is, for example, a lobby intercom installed in a lobby of a building. 2(a)-(c) show the structure of the entrance device 200, the home information screen 400, and the auxiliary device 600. FIG. 2(a) shows the structure of the entrance device 200. The entrance device 200 includes a processing unit 210, an operation unit 230, a control unit 240, and a communication unit 250. The processing unit 210 includes a camera unit 212, a microphone 214, a speaker 216, a monitor 218, and an IF unit 220.

The operation unit 230 of the entrance device 200 is a user interface for accepting operations from visitors, such as a call button. When the operation unit 230 accepts the number of the facility 110 scheduled to be visited from the visitor, the operation unit 230 outputs the call request to the control unit 240 . In addition, when the visitor operates the operation unit 230, the processing unit 210 operates.

The imaging unit 212 is equipped with solid-state imaging elements such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor and a CCD (Charge Coupled Device) image sensor to photograph visitors. The solid-state imaging element outputs an image signal obtained by photoelectric conversion to the IF unit 220 . The IF unit 220 performs various signal processing on the image signal from the imaging unit 212 . As long as the various signal processing uses well-known techniques, descriptions thereof are omitted here. The IF unit 220 outputs an image signal (hereinafter, also referred to as an “image signal”) obtained by performing signal processing to the control unit 240 .

The microphone 214 and the speaker 216 are user interfaces for visitors to communicate with residents. The microphone 214 collects the visitor's voice, converts it into an electrical signal, and outputs it to the IF unit 220 . The IF unit 220 receives the electrical signal from the microphone 214 and converts it into a signal in a form for transmission (hereinafter referred to as "sound signal"). The IF unit 220 outputs the sound signal to the control unit 240 . On the other hand, the IF unit 220 inputs an audio signal from the control unit 240 and converts the audio signal into an electrical signal. IF section 220 outputs an electrical signal to speaker 216 . The speaker 216 regenerates the electrical signal from the IF unit 220 and outputs sound.

The monitor 218 displays messages and the like. The IF unit 220 inputs a message signal from the control unit 240 and outputs the message signal to the monitor 218 . The message signal can also be generated in the entrance device 200. The control unit 240 controls the operation of the entrance device 200. The control unit 240 is connected to the communication unit 250 . The communication unit 250 is connected to the control device 300 via the common unit trunk line 310, and communicates with the home information panel 400 via the control device 300. To explain specifically, the communication unit 250 sends a call request and video signals to the home information panel 400, and transmits and receives audio signals and message signals to and from the home information panel 400. However, the signals are not limited to these. Figures 2(b)-(c) will be described below and return to Figure 7(a).

The control device 300 is installed in a shared space such as a mechanical room or a manager's room, and relays signals between the entrance device 200 and the home information screen 400 . At this time, the control device 300 extracts the transmission destination information included in the signal from the entrance device 200, and transmits the signal to the home information panel 400 of the transmission destination indicated in the extracted information. The shared trunk line 310 and the occupied trunk line 320 are transmission paths used to transmit call requests from the entrance device 200, response signals from the home information panel 400, etc., and are, for example, dedicated lines. The above-mentioned call request, video signal, voice signal, and message signal are transmitted on the shared trunk line 310 and the occupied trunk line 320.

The home information screen 400 is installed in the facility 110 and is also called a resident unit, a resident terminal, a living room base unit, and a home base unit. FIG. 2(b) shows the structure of the home information screen 400. The home information panel 400 includes a processing unit 410, an operation unit 430, a control unit 440, a first communication unit 450, and a second communication unit 460. The processing unit 410 includes a microphone 414, a speaker 416, a monitor 418, and an IF unit 420.

The first communication unit 450 is connected to the control device 300 via the possession trunk line 320, and communicates with the entrance device 200 via the control device 300. The control unit 440 is connected to the first communication unit 450, and the control unit 440 controls the operation of the home information panel 400. The control unit 440 is connected to the IF unit 420 and the operation unit 430 , and the IF unit 420 is connected to the microphone 414 , the speaker 416 , and the monitor 418 . Here, the microphone 414, the speaker 416, the IF unit 420, and the operation unit 430 are configured similarly to the microphone 214, the speaker 216, the IF unit 220, and the operation unit 230. The monitor 418 displays the image captured by the camera unit 212 of the entrance device 200 .

The control unit 440 receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450 . When the control unit 440 accepts the call request, the control unit 440 causes the call sound to be output from the speaker 416 via the IF unit 420 . Then, the control unit 440 displays the image obtained by reproducing the video signal on the monitor 418 via the IF unit 420 , and outputs the sound obtained by reproducing the audio signal from the speaker 416 via the IF unit 420 . When the resident who hears the call tone responds to the call by operating the operation unit 430, the control unit 440 causes the first communication unit 450 to communicate with the entrance device 200. As a result, an image signal is transmitted from the communication unit 250 to the first communication unit 450, and an audio signal is transmitted between the communication unit 250 and the first communication unit 450. Thereby, the visitor who operates the entrance device 200 and the visitor who operates the home information screen can communicate with each other. Calls between 400 residents can be carried out. Figure 2(c) will be described below and return to Figure 7(a).

(2) Incoming call processing including secondary device 600 The relay device 500 has a communication function corresponding to a wireless communication system such as a wireless LAN (Local Area Network), and relays signals between the home information panel 400 and the auxiliary device 600 included in the extension system. The relay device 500 is, for example, an AP (Access Point) mode router. In AP mode router, the wireless communication function is enabled but the router function is disabled. The auxiliary device 600 is also called an auxiliary master machine or a auxiliary master machine with a monitor, and can handle incoming calls with the entrance device 200 through the home information screen 400 .

FIG. 2(c) shows the structure of the secondary device 600. The secondary device 600 includes a processing unit 610, an operation unit 630, a control unit 640, and a communication unit 650. The processing unit 610 includes a microphone 614, a speaker 616, a monitor 618, and an IF unit 620. The microphone 614, the speaker 616, the monitor 618, the IF unit 620, and the operation unit 630 are configured similarly to the microphone 414, the speaker 416, the monitor 418, the IF unit 420, and the operation unit 430. The communication unit 650 has the same communication function corresponding to the wireless communication system as the relay device 500 . The communication unit 650 performs communication with the entrance device 200 via the relay device 500, the home information panel 400, and the control device 300 during incoming call processing. The control unit 640 is connected to the communication unit 650, and the control unit 640 controls the operation of the secondary device 600.

As described above, the control unit 440 of the home information panel 400 in FIG. 2(b) receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450. The control unit 440 sends the call request, video signal, and audio signal from the second communication unit 460 . The call request, video signal, and audio signal transmitted from the second communication unit 460 are received by the first secondary device 600a and the second secondary device 600b via the relay device 500 in FIG. 7(a) .

The communication unit 650 of the secondary device 600 in FIG. 2(c) receives a call request, an image signal, and an audio signal. When the communication unit 650 receives the call request, the control unit 640 causes the call sound to be output from the speaker 616 via the IF unit 620 . When the communication unit 650 receives the video signal and the audio signal, the control unit 640 displays the image obtained by reproducing the video signal on the monitor 618 via the IF unit 620 , and outputs the sound obtained by reproducing the audio signal from the speaker 616 via the IF unit 620 . When the resident who hears the call tone responds to the call by operating the operation unit 630, the control unit 640 notifies the home information panel 400 of the response via the communication unit 650, thereby causing the communication unit 650 to execute the communication with the entrance device 200. communication between. As a result, the video signal is transmitted from the communication unit 250 to the communication unit 650 via the home information panel 400 and the relay device 500 . Furthermore, the voice signal is transmitted between the communication unit 250 and the communication unit 650 via the home information panel 400 and the relay device 500 . By this, communication between the visitor who operates the entrance device 200 and the resident who operates the sub-device 600 is performed. Return to Figure 7(a).

(3) Incoming call processing including terminal device 800 The router 700 is a device for connecting the network in the first facility 110a to the external network 710 of the first facility 110a. The network 710 includes the Internet, and the server 720 is a device that performs specific processing on the Internet. The first terminal device 800a and the second terminal device 800b are communication devices such as smartphones, tablets, and PCs. The first terminal device 800a and the second terminal device 800b communicate with the server 720 via the network 710 by being connected to the router 700 or the relay device 500 in the first facility 110a. Furthermore, the first terminal device 800a and the second terminal device 800b communicate with the server 720 by being connected to the network 710 outside the first facility 110a. Furthermore, the first terminal device 800a and the second terminal device 800b are connected to the home information panel 400 via the router 700 or the relay device 500, so that the guest call processing with the entrance device 200 can be executed through the home information panel 400.

As described above, the control unit 440 of the home information panel 400 in FIG. 2(b) receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450. The control unit 440 sends the call request, video signal, and audio signal from the second communication unit 460 . The call request, video signal, and audio signal transmitted from the second communication unit 460 are received by the first terminal device 800a and the second terminal device 800b via the relay device 500 and the router 700 in FIG. 7(a) .

The terminal devices 800 such as the first terminal device 800a and the second terminal device 800b have the same configuration as in FIG. 2(c) and output a call tone when receiving a call request. When the terminal device 800 receives a video signal and an audio signal, it displays an image obtained by reproducing the video signal, and outputs a sound obtained by reproducing the audio signal. When the resident who hears the call tone responds to the call by operating the terminal device 800, the terminal device 800 communicates with the entrance device 200 by notifying the response to the home information panel 400. As a result, the communication unit 250 transmits a video signal to the terminal device 800 via the home information panel 400, the relay device 500, and the router 700. Furthermore, the voice signal is transmitted between the communication unit 250 and the terminal device 800 via the home information panel 400, the relay device 500, and the router 700. By this, communication between the visitor operating the entrance device 200 and the resident operating the terminal device 800 is performed.

In this way, the communication devices that can communicate with the second communication unit 460 of the home information panel 400 include the terminal device 800 that communicates via the router 700 and the secondary device 600 that does not communicate via the router 700 . Here, when the terminal device 800 is called a first type communication device, the secondary device 600 is called a second type communication device.

(4) Group control The following description will focus on the transmission of video signals before the incoming call starts. The image signal is a signal sent together with the call request. Particular attention is paid to the image signals sent from the home information screen 400 to a plurality of communication devices via the relay device 500. As mentioned above, the plurality of communication devices are collectively referred to as the plurality of secondary devices 600 and the plurality of terminal devices 800 . Before an incoming call starts, all communication devices must display an image including the visitor by receiving image signals. In order to improve the reliability of sending the video signal, it is ideal that the video signal is sent to each of the plurality of communication devices through unicast. However, the transmission of image signals requires a wider transmission band than the transmission of sound signals. Therefore, if the number of communication devices increases, the required transmission band will increase excessively.

In order to reliably transmit the video signal before the start of the incoming call and suppress the increase in the transmission band, the control unit 440 of the home information panel 400 in FIG. Communication device classification 2 groups. Group 2 is Group 1 and Group 2. Group 1 is the group that should send video signals, etc. with priority over Group 2. Therefore, it is the group with a higher priority than Group 2. As an example, a plurality of slave devices 600 are included in the first group, and a plurality of terminal devices 800 are included in the second group.

As described above, the first communication unit 450 receives the image signal from the entrance device 200 . Then, the control unit 440 controls the second communication unit 460 to transmit the video signal to the communication device included in the first group, such as the secondary device 600, prior to the communication device included in the second group, such as the terminal device 800. Here, when the image signal received from the entrance device 200 is called first information, the image signal sent from the second communication unit 460 is called second information.

In order to perform priority transmission, the control unit 440 uses the table of FIG. 8 . FIG. 8 shows the data structure of the table used in the control unit 440. This indicates the treatment of each group. As shown in the figure, the control unit 440 transmits the video signal in a unicast manner to the secondary device 600 included in the first group, and transmits the video signal in a multicast manner to the terminal device 800 included in the second group.

Here, unicast refers to a method in which the second communication unit 460 communicates with a communication device on a one-to-one basis, and selects a communication speed suitable for each communication device from a plurality of communication speeds specified in the wireless communication system. Furthermore, since the communication speed suitable for each communication device is selected, the communication speed of each communication device can be set to high speed. Furthermore, unicast is also combined with retransmission control. Therefore, through unicast, the reliability of sending video signals is improved. In this type of unicast, the speed of the image signal, that is, the quality of the image, can be changed for each communication device by applying the measurement results of the communication status of the wireless communication to each communication device. On the other hand, since the image signal is transmitted to each communication device, if the number of communication devices increases, the transmission frequency band used to transmit the image signal increases.

Multicast refers to a method in which the second communication unit 460 performs one-to-many communication with a plurality of communication devices, and selects the lowest communication speed among a plurality of communication speeds. Therefore, the communication speed of each communication device in multicast is lower than the communication speed of each communication device in unicast. On the other hand, since the image signal system is sent to a plurality of communication devices, even if the number of communication devices increases, the transmission frequency band used to send the image signal does not change. Therefore, through multicast, the increase in transmission bandwidth is suppressed.

Taking into consideration the difference between the communication speed of unicast and the communication speed of multicast, the control unit 440 adjusts the data quality when transmitting the video signal to the secondary device 600 included in the first group to the data quality when transmitting the video signal to the terminal device 800 included in the second group. The data quality of the video signal changes. For example, the image signal of the first group is set to a high bit rate/high frame rate compared to the image signal of the second group. Specifically, the bit rate/frame rate of the video signal of the first group is set to a value that can be transmitted at the communication speed of each communication device in unicast. Furthermore, the bit rate/frame rate of the video signal of the second group is set to a value that can be transmitted at the communication speed of each communication device in multicast. The bit rate/frame rate values are maintained in the control unit 440 .

Hereinafter, modification examples related to group control will be described. (Variation 1) Up to this point, the control unit 440 multicasts the video signal to the communication devices included in the second group. However, the control unit 440 may also switch between unicast and multicast for the communication devices included in the second group according to the communication status. An example of a communication situation is the traffic of a wireless communication system used by communication devices included in Group 2. For example, the control unit 440 measures the traffic volume of the second communication unit 460 . The measurement only needs to use publicly known techniques, and therefore the description is omitted here. The control unit 440 selects multicast when the traffic volume is above the threshold, and selects unicast when the traffic volume is less than the threshold. The second communication unit 460 transmits the video signal through multicast or unicast selected by the control unit 440 .

Furthermore, an example of the communication status may be the number of communication devices included in the second group. For example, the control unit 440 selects multicast when the number of stations is equal to or greater than the threshold, and selects unicast when the number of stations is less than the threshold. The second communication unit 460 transmits the video signal through multicast or unicast selected by the control unit 440 . On the other hand, the communication devices included in the first group transmit video signals by unicast in the same manner as before.

(Variation 2) The control unit 440 transmits the video signal in a unicast manner to the communication devices included in the first group. At this time, the control unit 440 may also variably set the data quality when transmitting image signals to the communication devices included in the first group according to the communication status. An example of a communication situation is the traffic of a wireless communication system used by communication devices included in Group 1. The control unit 440 measures the traffic volume of the second communication unit 460 . The measurement only needs to use publicly known techniques, and therefore the description is omitted here. The control unit 440 sets the quality of the image signal in such a manner that the lower the traffic volume, the higher the bit rate/frame rate.

Another example of communication conditions is the amount of interference in wireless communication systems used by communication devices included in Group 1. The control unit 440 measures the amount of interference for the second communication unit 460 . The measurement only needs to use publicly known techniques, and therefore the description is omitted here. The control unit 440 sets the quality of the image signal in such a manner that the lower the amount of interference, the higher the bit rate/frame rate. This kind of control can also be applied to the situation of transmitting image signals in a unicast manner to the communication devices included in the second group as in Variation 1.

(Variation 3) So far, the communication devices included in the first group and the communication devices included in the second group are fixed. For example, it is assumed that the slave device 600 is included in the first group and the terminal device 800 is included in the second group. However, the control unit 440 may also control the communication devices included in the first group and the communication devices included in the second group by changing the manner. At this time, priorities are given to each of the plurality of communication devices in advance, and the correspondence between each priority and the communication devices is registered in the control unit 440 . In addition, the control unit 440 predetermines the allowable number of communication devices included in the first group. The control unit 440 selects the communication devices included in the first group in descending order of priority of the communication devices connected to the second communication unit 460 until the allowed number is reached.

Here, for example, it is assumed that the priority order is set to the first secondary device 600a, the second secondary device 600b, the first terminal device 800a, and the second terminal device 800b in descending order, and the allowable number is set to "2 units". If both the first secondary device 600a and the second secondary device 600b are connected to the second communication unit 460, the control unit 440 includes the first secondary device 600a and the second secondary device 600b in the first group. On the other hand, if the first secondary device 600a is connected to the second communication unit 460 and the second secondary device 600b is not connected to the second communication unit 460, the control unit 440 switches the first secondary device 600a and the first terminal device 800a Included in Group 1.

Furthermore, the control unit 440 may also variably control the priority of each communication device. The second communication unit 460 measures the communication error rate or communication required time for each communication device. The measurement only needs to use publicly known techniques, and therefore the description is omitted here. The control unit 440 assigns priority to each of the plurality of communication devices based on the past communication error rate or the past communication required time. For example, the control unit 440 gives a higher priority to a communication device with a lower past communication error rate, or gives a higher priority to a communication device with a longer past communication time.

(Variation 4) So far, the number of groups has been set to 2, but the number of groups can also be 3 or more. For example, the control unit 440 further divides the second group into a plurality of groups and two groups. Here, when the group on the upper side of the divided second group is called the second group, the group on the lower side of the divided second group is called the third group. The control unit 440 transmits video signals in a multicast manner to the terminal devices 800 included in the third group, and transmits video signals in a unicast manner to the terminal devices 800 included in the second group. On the other hand, the quality of the image signal for the terminal device 800 included in the second group is lower than the quality of the image signal for the secondary device 600 included in the first group.

FIG. 7(b) is a configuration in which the relay device 500 is omitted from the configuration in FIG. 7(a). Therefore, the home information panel 400, the first auxiliary device 600a, and the second auxiliary device 600b are connected to the router 700 in the same manner as the terminal device 800. The processing of the intercom system 1000 in FIG. 7(b) is the same as the processing of the intercom system 1000 in FIG. 7(a), so the description is omitted here.

The main body of the device, system or method in the present invention includes a computer. By executing the program on the computer, the functions of the main body of the device, system or method in the present invention are realized. A computer has a processor as its main hardware component that operates according to a program. There is no limit to the type of processor as long as it can implement functions by executing programs. The processor includes one or a plurality of electronic circuits including a semiconductor integrated circuit (IC) or LSI (Large Scale Integration). A plurality of electronic circuits can be integrated into one chip, or can be provided on a plurality of chips. Multiple chips can be integrated into one device or installed in multiple devices. Programs are recorded on non-transitory recording media such as computer-readable ROM, optical disks, and hard disks. The program can be stored in the recording medium in advance, or can be provided to the recording medium via a wide area communication network including the Internet.

The operation of the intercom system 1000 constructed as above will be described. 9(a)-(b) are sequence diagrams showing communication steps performed by the intercom system 1000. Figure 9(a) shows the processing when multicast is used. The home information panel 400 receives the call request (S1010). A SIP (Session Initiation Protocol) call is established between the home information panel 400 and the first terminal device 800a (S1012). A SIP call is established between the home information panel 400 and the second terminal device 800b (S1014). The home information screen 400 multicasts the video signal to the first terminal device 800a and the second terminal device 800b (S1016, S1018). At this point, not only the video signal but also the audio signal can be sent in a multicast manner. The sound signal is the sound from the entrance device 200, such as the sound of a visitor calling (one-way only). The first terminal device 800a displays an image (S1020), and the second terminal device 800b displays an image (S1022). The first terminal device 800a responds to the call (S1024). A SIP call is established between the home information panel 400 and the first terminal device 800a (S1026), and the audio signal is unicast between the home information screen 400 and the first terminal device 800a (S1028). Thereafter, the home information panel 400 may also perform processing for ending the call processing to the second secondary device 600b.

Figure 9(b) shows the processing when unicast is used. The home information screen 400 receives the call request (S1050). A SIP call is established between the home information panel 400 and the first secondary device 600a (S1052). The home information screen 400 transmits the video signal to the first secondary device 600a in a unicast manner (S1054). A SIP call is established between the home information panel 400 and the second secondary device 600b (S1056). The home information screen 400 transmits the video signal to the second secondary device 600b in a unicast manner (S1058). It is also possible to send not only video signals but also audio signals in a unicast manner at the time points of steps 54 and 58. The sound signal is the sound from the entrance device 200, such as the sound of a visitor calling (one-way only). The first secondary device 600a displays an image (S1060), and the second secondary device 600b displays an image (S1062). The first secondary device 600a responds to the call (S1064). A SIP call is established between the home information screen 400 and the first secondary device 600a (S1066), and the audio signal is unicast between the home information screen 400 and the first secondary device 600a (S1068).

FIG. 10 is a sequence diagram showing the communication steps performed by the intercom system 1000. This represents the processing when using multicast and unicast. The home information screen 400 receives the call request (S1100). A SIP call is established between the home information panel 400 and the secondary device 600 (S1102). A SIP call is established between the home information screen 400 and the terminal device 800 (S1104). The home information screen 400 sends the video signal to the secondary device 600 in a unicast manner (S1106). The secondary device 600 displays the image (S1108). The home information screen 400 sends the video signal to the terminal device 800 in a multicast manner (S1110). The terminal device 800 displays the image (S1112). The secondary device 600 responds to the call (S1114). A SIP call is established between the home information screen 400 and the secondary device 600 (S1116), and the audio signal is unicast between the home information screen 400 and the secondary device 600 (S1118).

According to this embodiment, image signals are sent to the communication devices included in the first group among the plurality of communication devices prior to the communication devices included in the second group among the plurality of communication devices. Therefore, the reliability of sending the image signal can be improved. characteristics and can suppress the increase of transmission frequency band. Furthermore, since unicast is used for the first group and multicast is used for the second group, the reliability of transmitting the video signal to the first group can be improved. Furthermore, since unicast is used for the first group and multicast is used for the second group, the increase in the transmission band can be suppressed for the second group. Furthermore, since unicast is used for the first group and multicast is used for the second group, it is possible to reliably communicate with the communication device to which communication is to be given priority.

In addition, unicast and multicast for the communication devices included in the second group are switched according to the communication status, so the communication medium can be used efficiently. Furthermore, the data quality for the first group and the data quality for the second group are changed. Therefore, the image quality is set separately for a communication device that wants to display a high image quality and a communication device that does not have that level of high image quality. , therefore, communication media can be used efficiently. Furthermore, at least one of the data quality when transmitting the second information to the communication device included in the first group and the data quality when transmitting the second information to the communication device included in the second group is set, so that it can be effectively used. communication media.

In addition, the allowable number of communication devices included in the first group is stipulated, and the communication devices included in the first group are selected in descending order of the priority of the connected communication devices until the allowable number is reached. Therefore, flexibility can be achieved Set the communication device included in Group 1. Furthermore, since priority is given to each of the plurality of communication devices based on the past communication error rate or the time required for communication, the communication devices included in the first group can be flexibly set. Furthermore, since the second group is further divided into a plurality of groups, the degree of freedom of the structure can be increased.

An outline of one aspect of the present invention is as follows. A certain form of the home information screen (400) of the present invention is a home information screen (400) that can be installed in a facility (110), and is provided with: a first communication unit (450) that communicates with the entrance device (200); 2 communication units (460) that communicate with a plurality of communication devices; and a control unit (440) that controls the second communication unit (460). The first communication unit (450) receives the first information from the entrance device (200), and the second communication unit (460), when transmitting the second information based on the first information, gives priority to the communication devices included in the plurality of communication devices. The communication device in the second group sends the second information to the communication device included in the first group among the plurality of communication devices.

The second communication unit (460) may also transmit the second information in a unicast manner to the communication devices included in the first group, and may transmit the second information in a multicast manner to the communication devices included in the second group.

The second communication unit (460) may also switch between unicast and multicast for the communication devices included in the second group according to the communication status.

The second communication unit (460) may also change the data quality when transmitting the second information to the communication devices included in the first group and the data quality when transmitting the second information to the communication devices included in the second group.

The second communication unit (460) may also set the data quality when sending the second information to the communication devices included in the first group and the data quality when sending the second information to the communication devices included in the second group according to the communication status. At least 1.

The control unit (440) may also assign a priority to each of the plurality of communication devices and determine the allowable number of communication devices included in the first group in accordance with the priority of the communication devices connected to the second communication unit (460). Select the communication devices included in Group 1 in descending order until the allowed number is reached.

The control unit (440) may also assign priority to each of the plurality of communication devices based on past communication error rates or communication required time.

The control unit (440) may further divide the second group into a plurality of groups.

It may also include a residential information screen (400) and a plurality of communication devices.

It can also be equipped with a residential information screen (400) and an entrance device (200).

(Example 3) Next, Example 3 will be described. Embodiment 3, like Embodiment 2, relates to an intercom system installed in a collective facility. In Embodiment 2, wireless communication is performed between the home information panel and the auxiliary device, but in Embodiment 3, wired communication is performed between the home information panel and the auxiliary device. The entrance device 200, the home information screen 400, and the auxiliary device 600 of Embodiment 3 are of the same type as in Figures 2(a)-(c). Here, the explanation will focus on the differences from so far.

FIG. 11 shows the structure of the intercom system 1000. In the intercom system 1000, compared with FIG. 7(b), the home information panel 400 and the plurality of auxiliary devices 600 are connected by a wired cable 900 and an alarm wiring 910. The home information panel 400 and the plurality of auxiliary devices 600 communicate via a wired communication system such as Ethernet (registered trademark) via a wired cable 900 . That is, a wired communication system is used instead of the wireless communication system of Embodiment 2. In addition, the alarm wiring 910 connects the home information panel 400 and the plurality of sub-devices 600, and is also connected to sensors and the like. The control unit 440 of the home information panel 400 in FIG. 2(b) selects the communication device included in the first group based on the communication medium between each of the plurality of communication devices and the second communication unit 460. For example, the control unit 440 includes communication devices whose communication medium is wired in the first group, and includes communication devices whose communication medium is wireless in the second group. The processing of the intercom system 1000 is the same as that of Embodiment 2, so the description is omitted here.

According to this embodiment, communication devices included in the first group are selected based on communication media. Therefore, communication devices using communication media with less variation in communication conditions can be included in the first group. In addition, since communication devices using communication media with less variation in communication conditions are included in the first group, the communication success rate can be improved. In addition, the communication device included in the first group is selected according to the communication medium, so the degree of freedom of the configuration can be increased.

An outline of one aspect of the present invention is as follows. The control unit (440) may also select a communication device included in the first group based on the communication medium between each of the plurality of communication devices and the second communication unit (460).

(Example 4) Before describing the present invention in detail, an outline will be described. When the intercom system is installed in a collective facility such as a building, the entrance device is installed at the entrance of the collective facility, and a residential information screen is installed in a facility in the collective facility, such as a house, to implement the interaction between the entrance device and the residential information screen. call between guests. Furthermore, by connecting the auxiliary device installed in the facility to the home information panel, the auxiliary device can perform incoming calls between the home information panel and the entrance device. Furthermore, by connecting a terminal device such as a smartphone to the home information screen, the terminal device can also perform an incoming call between the home information screen and the entrance device. Before executing the guest call, the call request that triggers the start of the guest call is sent to the home information screen, secondary device, and terminal device together with the image signal of the visitor captured in the entrance device. However, there is a risk that a secondary device or terminal device may be unable to reproduce images.

The present invention was made in view of this situation, and an object thereof is to provide a technology that improves the reliability of receiving information when transmitting information to a plurality of communication devices.

This embodiment relates to an intercom system installed in collective facilities such as buildings and public residences. Collective facilities contain multiple housing and other facilities, and have at least one public entrance for people to enter and exit. Visitors operate the entrance devices such as the lobby intercom installed at the public entrance to call the residential information screen installed at the visited facility. Residents of the facility respond to calls and operate the home information screens to identify visitors. If the resident responds to the call by operating the home information panel, the guest call between the entrance device and the home information panel is performed.

Furthermore, in a facility, a sub-device may be installed in a room different from the room where the home information screen is installed. The auxiliary device communicates with the home information panel, and performs a guest call with the entrance device via the home information panel. Furthermore, facilities may sometimes be equipped with routers for accessing the Internet. Terminal devices such as smartphones, tablets, and PCs are connected to the Internet through routers. When the home information panel is connected to the router, communication can be performed between the home information panel and the terminal device via the router. Therefore, the terminal device performs a guest call with the entrance device via the home information screen.

In order to perform an incoming call on any one of the home information panel, the sub-device, and the terminal device, the call request from the entrance device must be sent not only to the home information panel but also from the home information panel to the sub-device and the terminal device. In addition, the sound signal and image signal obtained in the entrance device are also sent to the home information screen, auxiliary device, and terminal device together with the call request. Furthermore, when there are a plurality of slave devices or terminal devices, the call request, audio signal, and video signal are sent to all of the plurality of slave devices or terminal devices. When the resident responds to such a call request using any one of the home information panel, the auxiliary device, and the terminal device, for example, a auxiliary device, an incoming call is made between the auxiliary device and the entrance device. Hereinafter, a plurality of slave devices and a plurality of terminal devices are collectively referred to as "a plurality of communication devices". The plurality of communication devices may include only a plurality of slave devices, a plurality of terminal devices, or may include one or more slave devices and one or more terminal devices.

Before the incoming call starts, video signals are sent to multiple communication devices. However, after the incoming call starts, the video signal is sent to, for example, one secondary device. Therefore, compared with after the incoming call starts, a wider period of time is required before the incoming call starts. transmission band. In addition, there is a risk that the communication status of the network connected to the home information screen and multiple communication devices will cause adverse effects such as confusion of the visitor's image or sound, and the inability of the image signal to reach the communication device. This makes it impossible to confirm the visitor, so there is a need to improve the reliability of receiving video signals, etc.

When the communication device in the intercom system of this embodiment cannot receive the image signal that should be received together with the call signal, it requests the home information screen to send the image signal not as a dynamic image but as a static image. The home information screen that receives the request sends the image information converted into a static image to the communication device. Therefore, the communication device receives the image signal of the still image instead of the image signal of the dynamic image.

1(a)-(b) show the structure of the intercom system 1000. In FIG. 1(a) , the collective facility 100 includes a first facility 110a, a second facility 110b, and a third facility 110c collectively referred to as facilities 110. The intercom system 1000 includes an entrance device 200, a control device 300, a common trunk line 310, an occupied trunk line 320, a home information panel 400, a relay device 500, and a first auxiliary device 600a, a second auxiliary device 600b, which are collectively referred to as the auxiliary devices 600. Router 700, network 710, server 720, terminal device 800 and entrance slave 850. The number of facilities 110 in the collective facility 100 is not limited to "3", the number of auxiliary devices 600 is not limited to "2", and the number of terminal devices 800 is not limited to "1". The home information panel 400, the relay device 500, the secondary device 600, the router 700, and the terminal device 800 are shown only in the first facility 110a, but are also included in the second facility 110b and the third facility 110c. When the home information panel 400 is called an information terminal, the secondary device 600 and the terminal device 800 are called communication devices.

The intercom system 1000 includes: a main line system, which includes the entrance device 200, a control device 300, and a home information screen 400; and an extension system, which includes a home information screen 400, a secondary device 600, and a terminal device 800. The intercom system 1000 can perform incoming call processing, which is a call using sound and image between any one of the home information panel 400, the secondary device 600, the terminal device 800, and the entrance device 200. In the following, description will be given in the order of (1) incoming call processing in the trunk system, (2) incoming call processing including the secondary device 600, (3) incoming call processing including the terminal device 800, and (4) quality control of the video signal. .

(1) Incoming call processing in trunk system In the collective facility 100, a plurality of facilities 110 are concentrated. One example of the collective facilities 100 is a building, and one example of the facilities 110 is a house. The entrance device 200 is installed at the public entrance of the collective facility 100 . The entrance device 200 is, for example, a lobby intercom installed in a lobby of a building. 2(a)-(c) show the structure of the entrance device 200, the home information screen 400, and the auxiliary device 600. FIG. 2(a) shows the structure of the entrance device 200. The entrance device 200 includes a processing unit 210, an operation unit 230, a control unit 240, and a communication unit 250. The processing unit 210 includes a camera unit 212, a microphone 214, a speaker 216, a monitor 218, and an IF unit 220.

The operation unit 230 of the entrance device 200 is a user interface for accepting operations from visitors, such as a call button. When the operation unit 230 accepts the number of the facility 110 scheduled to be visited from the visitor, the operation unit 230 outputs the call request to the control unit 240 . In addition, when the visitor operates the operation unit 230, the processing unit 210 operates.

The imaging unit 212 is equipped with solid-state imaging elements such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor and a CCD (Charge Coupled Device) image sensor to photograph visitors. The solid-state imaging element outputs an image signal obtained by photoelectric conversion to the IF unit 220 . The IF unit 220 performs various signal processing on the image signal from the imaging unit 212 . As long as the various signal processing uses well-known techniques, descriptions thereof are omitted here. The IF unit 220 outputs an image signal (hereinafter, also referred to as an “image signal”) obtained by performing signal processing to the control unit 240 .

The microphone 214 and the speaker 216 are user interfaces for visitors to communicate with residents. The microphone 214 collects the visitor's voice, converts it into an electrical signal, and outputs it to the IF unit 220 . The IF unit 220 receives the electrical signal from the microphone 214 and converts it into a signal in a form for transmission (hereinafter referred to as "sound signal"). The IF unit 220 outputs the sound signal to the control unit 240 . On the other hand, the IF unit 220 inputs an audio signal from the control unit 240 and converts the audio signal into an electrical signal. IF section 220 outputs an electrical signal to speaker 216 . The speaker 216 regenerates the electrical signal from the IF unit 220 and outputs sound.

The monitor 218 displays messages and the like. The IF unit 220 inputs a message signal from the control unit 240 and outputs the message signal to the monitor 218 . The message signal can also be generated in the entrance device 200. The control unit 240 controls the operation of the entrance device 200. The control unit 240 is connected to the communication unit 250 . The communication unit 250 is connected to the control device 300 via the common unit trunk line 310, and communicates with the home information panel 400 via the control device 300. To explain specifically, the communication unit 250 sends a call request and video signals to the home information panel 400, and transmits and receives audio signals and message signals to and from the home information panel 400. However, the signals are not limited to these. Figures 2(b)-(c) will be described below and return to Figure 1(a).

The control device 300 is installed in a shared space such as a mechanical room or a manager's room, and relays signals between the entrance device 200 and the home information screen 400 . At this time, the control device 300 extracts the transmission destination information included in the signal from the entrance device 200, and transmits the signal to the home information panel 400 of the transmission destination indicated in the extracted information. The shared trunk line 310 and the occupied trunk line 320 are transmission paths used to transmit call requests from the entrance device 200, response signals from the home information panel 400, etc., and are, for example, dedicated lines. The above-mentioned call request, video signal, voice signal, and message signal are transmitted on the shared trunk line 310 and the occupied trunk line 320.

The home information screen 400 is installed in the facility 110 and is also called a resident unit, a resident terminal, a living room base unit, and a home base unit. FIG. 2(b) shows the structure of the home information screen 400. The home information panel 400 includes a processing unit 410, an operation unit 430, a control unit 440, a first communication unit 450, and a second communication unit 460. The processing unit 410 includes a microphone 414, a speaker 416, a monitor 418, and an IF unit 420.

The first communication unit 450 is connected to the control device 300 via the possession trunk line 320, and communicates with the entrance device 200 via the control device 300. The control unit 440 is connected to the first communication unit 450, and the control unit 440 controls the operation of the home information panel 400. The control unit 440 is connected to the IF unit 420 and the operation unit 430 , and the IF unit 420 is connected to the microphone 414 , the speaker 416 , and the monitor 418 . Here, the microphone 414, the speaker 416, the IF unit 420, and the operation unit 430 are configured similarly to the microphone 214, the speaker 216, the IF unit 220, and the operation unit 230. The monitor 418 displays the image captured by the camera unit 212 of the entrance device 200 .

The control unit 440 receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450 . When the control unit 440 accepts the call request, the control unit 440 causes the call sound to be output from the speaker 416 via the IF unit 420 . Then, the control unit 440 displays the image obtained by reproducing the video signal on the monitor 418 via the IF unit 420 , and outputs the sound obtained by reproducing the audio signal from the speaker 416 via the IF unit 420 . When the resident who hears the call tone responds to the call by operating the operation unit 430, the control unit 440 causes the first communication unit 450 to communicate with the entrance device 200. As a result, an image signal is sent from the communication unit 250 to the first communication unit 450, and an audio signal is transmitted between the communication unit 250 and the first communication unit 450. Thereby, the visitor who operates the entrance device 200 and the visitor who operates the home information screen can communicate with each other. Calls between 400 residents can be carried out. Figure 2(c) will be described below, returning to Figure 1(a).

(2) Incoming call processing including secondary device 600 The relay device 500 has a communication function corresponding to a wireless communication system such as a wireless LAN (Local Area Network), and relays signals between the home information panel 400 and the auxiliary device 600 included in the extension system. The relay device 500 is, for example, an AP (Access Point) mode router. In AP mode router, the wireless communication function is enabled but the router function is disabled. The auxiliary device 600 is also called an auxiliary master machine or a auxiliary master machine with a monitor, and can handle incoming calls with the entrance device 200 through the home information screen 400 .

FIG. 2(c) shows the structure of the secondary device 600. The secondary device 600 includes a processing unit 610, an operation unit 630, a control unit 640, and a communication unit 650. The processing unit 610 includes a microphone 614, a speaker 616, a monitor 618, and an IF unit 620. The microphone 614, the speaker 616, the monitor 618, the IF unit 620, and the operation unit 630 are configured similarly to the microphone 414, the speaker 416, the monitor 418, the IF unit 420, and the operation unit 430. The communication unit 650 has the same communication function corresponding to the wireless communication system as the relay device 500 . The communication unit 650 performs communication with the entrance device 200 via the relay device 500, the home information panel 400, and the control device 300 during incoming call processing. The control unit 640 is connected to the communication unit 650, and the control unit 640 controls the operation of the secondary device 600.

As described above, the control unit 440 of the home information panel 400 in FIG. 2(b) receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450. The control unit 440 sends the call request, video signal, and audio signal from the second communication unit 460 . The call request, video signal, and audio signal transmitted from the second communication unit 460 are received by the first secondary device 600a and the second secondary device 600b via the relay device 500 in FIG. 1(a).

The communication unit 650 of the secondary device 600 in FIG. 2(c) receives a call request, an image signal, and an audio signal. When the communication unit 650 receives the call request, the control unit 640 causes the call sound to be output from the speaker 616 via the IF unit 620 . When the communication unit 650 receives the video signal and the audio signal, the control unit 640 displays the image obtained by reproducing the video signal on the monitor 618 via the IF unit 620 , and outputs the sound obtained by reproducing the audio signal from the speaker 616 via the IF unit 620 . When the resident who hears the call tone responds to the call by operating the operation unit 630, the control unit 640 notifies the home information panel 400 of the response via the communication unit 650, thereby causing the communication unit 650 to execute the communication with the entrance device 200. communication between. As a result, the video signal is transmitted from the communication unit 250 to the communication unit 650 via the home information panel 400 and the relay device 500 . Furthermore, the voice signal is transmitted between the communication unit 250 and the communication unit 650 via the home information panel 400 and the relay device 500 . By this, communication between the visitor who operates the entrance device 200 and the resident who operates the sub-device 600 is performed. Return to Figure 1(a).

(3) Incoming call processing including terminal device 800 The router 700 is a device for connecting the network in the first facility 110a to the external network 710 of the first facility 110a. The network 710 includes the Internet, and the server 720 is a device that performs specific processing on the Internet. The terminal device 800 is a communication device such as a smartphone, tablet, or PC. The terminal device 800 communicates with the server 720 via the network 710 by being connected to the router 700 or the relay device 500 in the first facility 110a. Furthermore, the terminal device 800 communicates with the server 720 by connecting to the network 710 outside the first facility 110a. Furthermore, by connecting to the home information panel 400 via the router 700 or the relay device 500, the terminal device 800 can execute the guest call processing with the entrance device 200 via the home information panel 400.

As described above, the control unit 440 of the home information panel 400 in FIG. 2(b) receives the call request, video signal, and audio signal from the entrance device 200 via the first communication unit 450. The control unit 440 sends the call request, video signal, and audio signal from the second communication unit 460 . The call request, video signal, and audio signal transmitted from the second communication unit 460 are received by the terminal device 800 via the relay device 500 and the router 700 in FIG. 1(a) .

The terminal device 800 has the same configuration as in FIG. 2(c) and outputs a call tone when receiving a call request. When the terminal device 800 receives a video signal and an audio signal, it displays an image obtained by reproducing the video signal, and outputs a sound obtained by reproducing the audio signal. When the resident who hears the call tone responds to the call by operating the terminal device 800, the terminal device 800 communicates with the entrance device 200 by notifying the response to the home information panel 400. As a result, the communication unit 250 transmits a video signal to the terminal device 800 via the home information panel 400, the relay device 500, and the router 700. Furthermore, the voice signal is transmitted between the communication unit 250 and the terminal device 800 via the home information panel 400, the relay device 500, and the router 700. By this, communication between the visitor operating the entrance device 200 and the resident operating the terminal device 800 is performed.

In this way, the communication devices that can communicate with the second communication unit 460 of the home information panel 400 include the terminal device 800 that communicates via the router 700 and the secondary device 600 that does not communicate via the router 700 . Here, when the terminal device 800 is called a first type communication device, the secondary device 600 is called a second type communication device.

(4) Quality control of image signals The following description will focus on the transmission of video signals before the incoming call starts. The image signal is a signal sent together with the call request. Particular attention is paid to the image signals sent from the home information screen 400 to a plurality of communication devices via the relay device 500. As mentioned above, the plurality of communication devices are collectively referred to as the plurality of secondary devices 600 and the plurality of terminal devices 800 . Before an incoming call starts, all communication devices must display an image including the visitor by receiving image signals. To transmit video signals to a plurality of communication devices, unicast or multicast is used.

Here, unicast refers to a method in which the second communication unit 460 communicates with a communication device on a one-to-one basis, and selects a communication speed suitable for each communication device from a plurality of communication speeds specified in the wireless communication system. Furthermore, since the communication speed suitable for each communication device is selected, the communication speed of each communication device can be set to high speed. Furthermore, unicast is also combined with retransmission control. Therefore, through unicast, the reliability of sending video signals is improved. In this type of unicast, the speed of the image signal, that is, the quality of the image, can be changed for each communication device by applying the measurement results of the communication status of the wireless communication to each communication device. On the other hand, since the image signal is transmitted to each communication device, if the number of communication devices increases, the transmission frequency band used to transmit the image signal increases.

Multicast refers to a method in which the second communication unit 460 performs one-to-many communication with a plurality of communication devices, and selects the lowest communication speed among a plurality of communication speeds. Therefore, the communication speed of each communication device in multicast is lower than the communication speed of each communication device in unicast. On the other hand, since the image signal system is sent to a plurality of communication devices, even if the number of communication devices increases, the transmission frequency band used to send the image signal does not change. Therefore, through multicast, the increase in transmission bandwidth is suppressed.

Regarding the selection of unicast or multicast, as long as the reliability of the transmitted image signal and the transmission frequency band are taken into consideration, it can be made in the control unit 440 of the residential information screen 400, for example. In this embodiment, the following situation is assumed: no matter which one of unicast and multicast is selected, it is difficult for the communication device to receive the image signal. Here, the slave device 600 will be described as an example of the communication device, and the same process may be performed in the terminal device 800 as well.

As described above, the communication unit 650 of the auxiliary device 600 in FIG. 2(c) receives the image signal transmitted from the home information screen 400 through the communication between the entrance device 200 and the home information screen 400. At this time, the control unit 640 sets the quality of the image signal when the communication unit 650 receives the image signal. As the quality of the video signal, for example, two levels of quality are defined. The first quality is a moving image, and the second quality is a still image. In addition, the first quality may be a high bit rate, that is, a high quality moving image, and the second quality may be a low bit rate, that is, a low quality moving image. Therefore, the second quality can be considered to be a lower quality than the first quality.

The control unit 640 periodically measures the communication status of the wireless communication between the communication unit 650 and the first communication unit 450 of the home information panel 400 via the relay device 500 when incoming calls are not being executed. As the communication status of the wireless communication, for example, communication speed and throughput are measured, and known techniques can be used for these measurements, so descriptions thereof are omitted here. 12(a)-(b) show the data structure of the table used in the control unit 640. Figure 12(a) shows the relationship between the measured communication speed and the quality of the image signal. The control unit 640 selects a moving image as the quality of the video signal when the communication speed is above the threshold, and selects a still image as the quality of the video signal when the communication speed is lower than the threshold. Here, the threshold is set based on the boundary between whether the communication unit 650 can receive the video signal of the moving image. The threshold value may be obtained by simulation calculation, for example. When the communication status of wireless communication is throughput, the control unit 640 performs the same process as the above-mentioned process on the throughput instead of the communication speed. Figure 12(b) will be described below and return to Figure 2(c).

In this way, the control unit 640 sets the quality of the moving image as the image signal when the communication unit 650 can receive the image signal of the moving image, and sets the quality of the static image when the communication unit 650 cannot receive the image signal of the moving image. The quality of an image as an image signal. When the control unit 640 has set the moving image as the quality of the video signal, the communication unit 650 receives the video signal in the same manner as described so far. On the other hand, when the control unit 640 has set a still image as the quality of the image signal, the communication unit 650 sends a signal for requesting transmission of the image signal of the still image (hereinafter referred to as "still image request signal"). ") is sent to the home information panel 400 via the relay device 500. The still image request signal includes identification information for identifying the communication device that is the sender.

The second communication unit 460 of the home information panel 400 in FIG. 2(b) receives the still image request signal. Then, the control unit 440 converts the image signal of the moving image received by the first communication unit 450 into an image signal of the still image. The control unit 440 causes the image signal of the still image to be sent from the communication unit 650 to the secondary device 600 that has sent the still image request signal. The communication unit 650 of the secondary device 600 in FIG. 2(c) receives the image signal of the still image. The control unit 640 reproduces the still image, and the monitor 618 displays the still image.

Hereinafter, modification examples related to quality control of image signals will be described. (Variation 1) The communication unit 650 of the secondary device 600 in FIG. 2(c) measures the communication success rate in a specific period under the condition that the image signal of the moving image is received. This measurement only needs to use publicly known techniques, so the description is omitted here. Figure 12(b) shows the relationship between the measured communication success rate and the quality of the image signal. The control unit 640 selects a dynamic image as the quality of the image signal when the communication success rate is higher than the threshold, and selects a still image as the quality of the image signal when the communication success rate is lower than the threshold. Here, the threshold is also set based on the boundary of whether the communication unit 650 can receive the image signal of the moving image. The threshold value may be obtained by simulation calculation, for example. Return to Figure 2(c). In this way, the control unit 640 sets the quality of the still image as the image signal when the communication success rate in the specific period does not reach the threshold when the communication unit 650 has received the image signal of the moving image. Furthermore, the communication unit 650 transmits the still image request signal to the home information panel 400 via the relay device 500 . In this situation, when sending the next call request, the home information panel 400 sends the image signal of the still image to the secondary device 600 that has sent the still image request signal.

(Variation 2) When the communication device is the terminal device 800, the terminal device 800 can also execute applications other than applications for incoming calls. When the terminal device 800 is executing an application using the same port as the port used to receive the call request and the image signal, even if it receives the image signal, it cannot use the port used to receive the image signal. At this time, the control unit (not shown) of the terminal device 800 sets the quality of the still image as the video signal. That is, the control unit sets the quality of the image signal based on the communication status in the communication unit (not shown) of the terminal device 800 . Then, the terminal device 800 transmits the still image request signal to the home information panel 400 via the relay device 500 . Furthermore, two or more types of control in the Example, Modification 1, and Modification 2 may be arbitrarily combined.

(Variation 3) So far, the quality of the image signal has been set in the communication device. However, the quality of the image signal can also be set in the control unit 440 of the home information screen 400 in FIG. 2(b). At this time, priorities are given to each of the plurality of communication devices in advance, and the correspondence between each priority and the communication devices is registered in the control unit 440 . In addition, the control unit 440 predetermines the allowable number of communication devices that should transmit video signals of moving images. The control unit 440 selects the communication device to which the image signal of the moving image should be transmitted in descending order of priority of the communication device connected to the second communication unit 460 until the allowable number is reached. The second communication unit 460 sends an image signal of the moving image to the communication device selected by the control unit 440 . On the other hand, the second communication unit 460 transmits the image signal of the still image to the communication device not selected by the control unit 440 .

(Variation 4) So far, it is assumed that the quality of the video signal is the control object, the first quality is the moving image, and the second quality is the moving image. However, the quality of the sound signal can also be set as a control object. At this time, the first quality is real-time data, and the second quality is any one of non-real-time data, fixed data, and text data.

FIG. 1(b) is a configuration in which the relay device 500 is omitted from the configuration in FIG. 1(a). Therefore, the home information panel 400, the first auxiliary device 600a, and the second auxiliary device 600b are connected to the router 700 in the same manner as the terminal device 800. The processing of the intercom system 1000 in FIG. 1(b) is the same as the processing of the intercom system 1000 in FIG. 1(a), so the description is omitted here.

The main body of the device, system or method in the present invention includes a computer. By executing the program on the computer, the functions of the main body of the device, system or method in the present invention are realized. A computer has a processor as its main hardware component that operates according to a program. There is no limit to the type of processor as long as it can implement functions by executing programs. The processor includes one or a plurality of electronic circuits including a semiconductor integrated circuit (IC) or LSI (Large Scale Integration). A plurality of electronic circuits can be integrated into one chip, or can be provided on a plurality of chips. Multiple chips can be integrated into one device or installed in multiple devices. Programs are recorded on non-transitory recording media such as computer-readable ROM, optical disks, and hard disks. The program can be stored in the recording medium in advance, or can be provided to the recording medium via a wide area communication network including the Internet.

The operation of the intercom system 1000 constructed as above will be described. 4(a)-(b) are sequence diagrams showing communication steps performed by the intercom system 1000. Figure 4(a) shows the processing when multicast is used. The home information panel 400 receives the call request (S10). A SIP (Session Initiation Protocol) call is established between the home information panel 400 and the first secondary device 600a (S12). A SIP call is established between the home information panel 400 and the second secondary device 600b (S14). The home information screen 400 multicasts the video signal to the first secondary device 600a and the second secondary device 600b (S16, S18). At this point, not only the video signal but also the audio signal can be sent in a multicast manner. The sound signal is the sound from the entrance device 200, such as the sound of a visitor calling (one-way only). The first secondary device 600a displays an image (S20), and the second secondary device 600b displays an image (S22). The first secondary device 600a responds to the call (S24). A SIP call is established between the home information screen 400 and the first secondary device 600a (S26), and the audio signal is unicast between the home information screen 400 and the first secondary device 600a (S28). Thereafter, the home information panel 400 may also perform processing for ending the call processing to the second secondary device 600b.

Figure 4(b) shows the processing when unicast is used. The home information panel 400 receives the call request (S50). A SIP call is established between the home information panel 400 and the first secondary device 600a (S52). The home information screen 400 transmits the video signal to the first secondary device 600a in a unicast manner (S54). A SIP call is established between the home information panel 400 and the second secondary device 600b (S56). The home information screen 400 sends the video signal to the second secondary device 600b in a unicast manner (S58). It is also possible to send not only video signals but also audio signals in a unicast manner at the time points of steps 54 and 58. The sound signal is the sound from the entrance device 200, such as the sound of a visitor calling (one-way only). The first secondary device 600a displays an image (S60), and the second secondary device 600b displays an image (S62). The first secondary device 600a responds to the call (S64). A SIP call is established between the home information screen 400 and the first secondary device 600a (S66), and the audio signal is unicast between the home information screen 400 and the first secondary device 600a (S68).

FIG. 13 is a sequence diagram showing the communication steps performed by the intercom system 1000. Here, as an example, multicast is used. The home information panel 400 receives the call request (S2100). A SIP call is established between the home information panel 400 and the first secondary device 600a (S2102). A SIP call is established between the home information panel 400 and the second secondary device 600b (S2104). The home information screen 400 multicasts the video signal to the first secondary device 600a and the second secondary device 600b (S2106, S2108). The first secondary device 600a displays the image (S2110), but the second secondary device 600b cannot display the image (S2112). The second secondary device 600b sends an error response to the home information panel 400 (S2114). A SIP call is established between the home information panel 400 and the second secondary device 600b (S2116). The second secondary device 600b transmits the still image request signal to the home information panel 400 (S2118). The home information panel 400 sends the still image to the second sub-device 600b (S2120). The second secondary device 600b displays a still image (S2122).

According to this embodiment, the quality of the image signal when receiving the image signal is set. Therefore, the reliability of receiving the image signal can be improved when the image signal is sent to a plurality of communication devices. In addition, the quality of the video signal when receiving the video signal is set, so the amount of data communication consuming the transmission band can be reduced. Furthermore, since the amount of data communication consuming the transmission band is reduced, the communication band can be used efficiently. In addition, since the amount of data communication consuming the transmission band is reduced, the image signal can be reliably received in the communication device that wants to display the image.

In addition, the quality of the image signal is set according to the communication situation, so the reliability of receiving the image signal can be improved. In addition, even if the moving image receiving port is used, the image signal of the still image is received, so the still image can be displayed. Furthermore, when the image signal of the moving image cannot be received, the image signal of the still image is requested to be sent, so that the image signal of the still image can be received. In addition, since the image signal of the still image is received, the transmission band can be used efficiently. Furthermore, when the image signal of the moving image has been received and the communication success rate in a specific period does not reach the threshold, the still image is set as the image signal, so that the image signal of the still image can be received.

In addition, the first quality may be real-time data, and the second quality may be any one of non-real-time data, fixed data, and text data. Therefore, this embodiment or modifications 1 to 3 may also be applied to audio signals. Furthermore, by setting the priority order for the communication devices, the communication device to which the video signal of the moving image should be transmitted can be automatically selected according to the situation.

An outline of one aspect of the present invention is as follows. A communication device of a certain form of the present invention includes: a communication unit that communicates with a home information panel (400) in a facility (110) that communicates with an entrance device (200); and a control unit that controls the communication unit. The communication unit receives information transmitted from the home information panel (400) through communication between the entrance device (200) and the home information panel (400), and the control unit sets the quality of the information when the communication unit receives the information.

The control unit can also set the quality of information according to the communication status in the communication unit.

The control unit may set the second quality lower than the first quality when the communication unit cannot receive the information of the first quality, and the communication unit may set the second quality to the communication unit when the control unit has set the second quality. The housing information screen (400) requests second quality information.

Alternatively, when the communication unit has received information of the first quality and the communication success rate in a specific period does not reach the threshold, the control unit sets the second quality lower than the first quality and communicates When the control unit has set the second quality, the unit requests the second quality information from the home information panel (400).

The first quality may be a moving image, and the second quality may be a still image.

The first quality may be real-time data, and the second quality may be any one of non-real-time data, fixed data, and text data.

It may also be equipped with a communication device and a residential information screen (400).

It may also be provided with communication devices, residential information screens (400) and entrance devices (200).

As above, the present invention has been described based on the embodiments. This embodiment is an example, and those in the industry should understand that various variations may exist in the combination of each component or each processing procedure, and such variations are also within the scope of the present invention.

In Embodiments 1 and 4, the home information panel 400 and the plurality of secondary devices 600 are connected by a wireless communication system via the relay device 500 . However, it is not limited to this. For example, the home information screen 400 and the plurality of secondary devices 600 may also be connected through a wired communication system such as Ethernet (registered trademark). At this time, the home information panel 400 and the plurality of auxiliary devices 600 are also connected through alarm wiring connected to sensors and the like. According to this variation, the degree of freedom of the structure can be increased.

The processing performed in the entrance device 200 of Embodiments 1 to 4 can also be executed by the entrance slave machine 850 instead of the entrance device 200 . The entrance sub-machine 850 is a device installed at the entrance of the facility 110 . According to this variation, the degree of freedom of the structure can be increased.

This embodiment can also be specified by the following items. [Item 1-1] An information terminal that can be installed in a facility and has: The first communication unit communicates with the entrance device; a second communication unit that communicates with a plurality of communication devices; and A control unit that controls the above-mentioned second communication unit; The above-mentioned first communication unit receives the first information from the above-mentioned entrance device, and When transmitting the second information based on the first information, the second communication unit gives priority to the communication devices included in the second group among the plurality of communication devices. The communication device of group 1 sends the above-mentioned second information. [Item 1-2] Such as the information terminal of item 1-1, wherein the above-mentioned second communication unit sends the above-mentioned second information in a unicast manner to the communication devices included in the above-mentioned group 1, and in a multicast manner to the communication devices included in the above-mentioned group 2. method to send the above-mentioned second information. [Item 1-3] Such as the information terminal of item 1-2, wherein the above-mentioned second communication unit switches the above-mentioned unicast and the above-mentioned multicast for the communication devices included in the above-mentioned second group according to the communication status. [Item 1-4] Such as the information terminal in any one of items 1-1 to 1-3, wherein the above-mentioned second communication unit ensures that the data quality when sending the above-mentioned second information to the communication devices included in the above-mentioned group 1 is consistent with the data quality when sending the above-mentioned second information to the communication devices included in the above-mentioned group 2. The data quality changes when the included communication device sends the above-mentioned second information. [Items 1-5] Such as the information terminal of Item 1-4, wherein the above-mentioned second communication unit sets the data quality when sending the above-mentioned second information to the communication devices included in the above-mentioned group 1 and the communication device included in the above-mentioned group 2 according to the communication status. At least 1 of the data quality when sending the second information above. [Items 1-6] The information terminal of any one of items 1-1 to 1-5, wherein the control unit selects the communication medium included in the first group based on the communication media between each of the plurality of communication devices and the second communication unit. Communication device. [Items 1-7] The information terminal of any one of items 1-1 to 1-5, wherein the control unit assigns priority to each of the plurality of communication devices and stipulates the allowable number of communication devices included in the first group, The communication devices included in the first group are selected in descending order of priority of the communication devices connected to the second communication unit until the allowed number is reached. [Items 1-8] Such as the information terminal of items 1-7, wherein the control unit assigns priority to each of the plurality of communication devices based on past communication error rates or communication required times. [Items 1-9] Such as the information terminal of any one of items 1-1 to 1-8, wherein the control unit further divides the second group into a plurality of groups. [Items 1-10] A communication system, which includes an information terminal as in any one of items 1-1 to 1-9, and a plurality of communication devices as described above. [Items 1-11] An intercom system, which is provided with an information terminal as in any one of items 1-1 to 1-9, and the above-mentioned entrance device.

[Item 2-1] A communication device having: The communications department, which communicates with the information terminals in the facility that communicate with the entrance device; and A control unit, which controls the above-mentioned communication unit; The communication unit receives information transmitted from the information terminal through communication between the entrance device and the information terminal, and The control unit sets the quality of information when the communication unit receives information. [Item 2-2] The communication device of item 2-1, wherein the control unit sets the quality of the information based on the communication status in the communication unit. [Item 2-3] Such as the communication device of item 2-1 or 2-2, wherein the above-mentioned control unit sets a second quality lower than the above-mentioned first quality when the above-mentioned communication unit cannot receive information of the first quality, and The communication unit requests the information of the second quality from the information terminal when the control unit has set the second quality. [Item 2-4] For example, the communication device of Item 2-1 or 2-2, wherein the above-mentioned control unit is set to be higher than the above-mentioned first-quality information when the communication success rate in a specific period does not reach the threshold under the condition that the above-mentioned communication unit has received the first-quality information. 1 quality is lower than the 2nd quality, and The communication unit requests the information of the second quality from the information terminal when the control unit has set the second quality. [Item 2-5] Such as the communication device of item 2-3 or 2-4, wherein the above-mentioned first quality is a dynamic image, and the above-mentioned second quality is a still image. [Item 2-6] For example, the communication device of item 2-3 or 2-4, wherein the above-mentioned first quality is real-time data, and the above-mentioned second quality is any one of non-real-time data, fixed data, and text data. [Item 2-7] A communication system provided with the communication device according to any one of items 2-1 to 2-6, and the above-mentioned information terminal. [Item 2-8] An intercom system, which is provided with the communication device according to any one of items 2-1 to 2-6, the above-mentioned information terminal and the above-mentioned entrance device.

100:Group facilities 110: Facilities 110a: Facility 1 110b: 2nd facility 110c: 3rd facility 200: Entrance device 210:Processing Department 212:Camera Department 214:Microphone 216:Speaker 218:Monitor 220:IF Department 230:Operation Department 240:Control Department 250: Ministry of Communications 300:Control device 310: Common trunk line 320:Occupy trunk line 400: Residential information screen (information terminal) 410:Processing Department 414:Microphone 416: Speaker 418:Monitor 420:IF department 430:Operation Department 440:Control Department 450: 1st Communications Department 460: 2nd Communications Department 500:Relay device 600: Secondary device (communication device) 600a: 1st auxiliary device 600b: 2nd auxiliary device 610:Processing Department 614:Microphone 616: Speaker 618:Monitor 620:IF Department 630:Operation Department 640:Control Department 650: Ministry of Communications 700:Router 710:Internet 720:Server 800: Terminal device (communication device) 800a: First terminal device 800b: Second terminal device 850: Porch sub-machine (porch device) 900: Wired cable 910:Alarm wiring 1000:Intercom system

1(a)-(b) are diagrams showing the structure of the intercom system of Embodiment 1. Figures 2(a)-(c) are diagrams showing the composition of the entrance device, home information screen, and auxiliary devices of Figure 1(a)-(b). 3(a)-(b) are diagrams showing the data structure of the table used in the control part of FIG. 2(b). Figures 4(a)-(b) are sequence diagrams showing the communication steps performed by the intercom system of Figures 1(a)-(b). 5(a)-(c) are flowcharts showing the selection steps performed by the control unit in FIG. 2(b). FIG. 6 is a flowchart showing the transmission procedure performed by the second communication unit in FIG. 2(b). 7(a)-(b) are diagrams showing the structure of the intercom system of Embodiment 2. FIG. 8 is a diagram showing the data structure of a table used in the control unit of the second embodiment. Figures 9(a)-(b) are sequence diagrams showing communication steps performed by the intercom system of Figures 7(a)-(b). FIG. 10 is a sequence diagram showing the communication steps performed by the intercom system of FIGS. 7(a)-(b). Fig. 11 is a diagram showing the structure of the intercom system according to Embodiment 3. 12(a)-(b) are diagrams showing the data structure of a table used in the control unit of Embodiment 4. Fig. 13 is a sequence diagram showing the communication procedures performed by the intercom system of Embodiment 4.

200: Entrance device

210:Processing Department

212:Camera Department

214:Microphone

216:Speaker

218:Monitor

220:IF Department

230:Operation Department

240:Control Department

250: Ministry of Communications

310: Common trunk line

320:Occupy trunk line

400: Residential information screen (information terminal)

410:Processing Department

414:Microphone

416: Speaker

418:Monitor

420:IF Department

430:Operation Department

440:Control Department

450: 1st Communications Department

460: 2nd Communications Department

600: Secondary device (communication device)

610:Processing Department

614:Microphone

616: Speaker

618:Monitor

620:IF Department

630:Operation Department

640:Control Department

650: Ministry of Communications

Claims (9)

An information terminal that can be installed in a facility and is provided with: a first communication unit that communicates with the entrance device; a second communication unit that communicates with the communication device; and a control unit that controls the second communication unit; and a speaker, which can output sound based on communication with the above-mentioned first communication unit; and the above-mentioned control unit selects multicast or unicast to cause the above-mentioned second communication unit to send information before the above-mentioned communication device responds, and the above-mentioned After the communication device responds, the above-mentioned second communication unit transmits the information through unicast. Such as the information terminal of claim 1, wherein the communication speed of each communication device in the multicast is lower than the communication speed of each communication device in the unicast. If the information terminal of claim 1 or 2 is requested, when the above-mentioned second communication unit has acquired specific information from the above-mentioned first communication unit, if the above-mentioned control unit selects unicast, the communication speed of each of the above-mentioned communication devices shall be at the first communication speed. The communication speed transmits information corresponding to the above-mentioned specific information. If the above-mentioned control unit selects multicast, the communication speed of each above-mentioned communication device is a second communication speed lower than the above-mentioned first communication speed and transmits the above-mentioned specific information corresponding to it. information. The information terminal of claim 1, wherein when the above-mentioned second communication unit has acquired the moving image information from the above-mentioned first communication unit, if the above-mentioned control unit selects unicast, it sends the moving image information; if the above-mentioned control unit selects multicast Then send static image information or continuous static image information. Such as the information terminal of claim 1, wherein the control unit selects multicast or unicast based on input from the outside. Such as the information terminal of claim 1, wherein the control unit selects multicast or unicast according to the communication environment. The information terminal of claim 1, wherein the control unit selects multicast or unicast according to the number of the communication devices connected to the second communication unit. The information terminal of claim 1, wherein the communication device capable of communicating with the second communication unit includes a first communication device that communicates via a router, and a second communication device that communicates without the router. An intercom system, which is provided with the information terminal of claim 1 and the above-mentioned entrance device that communicates with the above-mentioned information terminal.