WIRELESS COMMUNICATION USING HIGH FREQUENCY SIGNAL

TECHNICAL FIELD

[0001] The present invention relates to

communications using high frequency bands, for example 57 to 63 GHz frequency band or above.

BACKGROUND

[0002] WO2010/090785A1 and US2010/ 0285823A1 disclose communication systems using the millimeter wave band. The millimeter waves are typically a frequency band between 30GHz and 300GHz, and high capacity channel is available using such a high

frequency. Further, recently, communication using frequency band above 300GHz has been proposed to obtain more capacity. The frequency band above 300GHz is normally referred to as a terahertz frequency band.

[0003] Currently, Ultra-High Definition Television (UHTV) has been proposed. A 600Mbps channel is

required for transmitting a compressed UHTV signal, and a 2.4Gbps channel is required for transmitting an uncompressed UHTV signal. In case a UHTV camera sends a UHTV signal to a receiving device from outside the studio for a live telecast, a LTE (Long Term Evolution) mobile network specified by the 3 ^rd Generation

Partnership Project (3GPP) is not enough because a channel provided by the LTE mobile network is up to 75Mbps channel.

[0004] On the contrary, a communication system using the millimeter wave band or above frequency band can provide a 3Gbps channel, and is suitable for future television system, which requires high capacity

channels .

[0005] However, the characteristic of such a high frequency signal is similar to that of light, and line of sight between a sending device and a receiving device is required for proper communications. However, line of sight is not always available if one of the terminals in the communication is a mobile terminal.

SUMMARY

[0006] In accordance with a first aspect of the present invention, a server for establishing a

communication channel from a transmitting device to a receiving device by controlling reflecting systems including one or more reflecting members is provided. Here, each reflecting member of the one or more

reflecting members reflects a signal generated by the transmitting device. The server includes a database unit configured to store location information of reflecting members; a communication unit configured to receive a request message from the transmitting device including position information of the transmitting device; and a determination unit configured to

determine one or more reflecting members used for establishing the communication channel, a direction of each determined reflecting member, and a transmission direction of the transmitting device based on the position information of the transmitting device, the location information of the reflecting members and position information of the receiving device. The communication unit is further configured to transmit the determined direction to corresponding reflecting member and the transmission direction to the

transmitting device.

[0007] Further, the determination unit may be configured to determine a receive direction of the receiving device, and the communication unit may be configured to transmit the receiving direction to the receiving device. Further, the determination unit may be configured to determine a frequency of the signal generated by the transmitting device based on used frequencies for other communication channels.

[0008] The server may include a reservation unit configured to reserve one or more reflecting members and a frequency for the communication channel based on the position information of the receiving device, estimated position information of the transmitting device and a use period of the communication channel.

[0009] The position information of the receiving device may be received from the receiving device or the transmitting device, and the server may include a reservation unit configured to reserve one or more reflecting members and a frequency for the

communication channel based on estimated position information of the receiving device, estimated position information of the transmitting device and a use period of the communication channel.

[0010] Further, the communication unit may

transmit the determined direction to corresponding reflecting member when the server receives a selection input of the transmitting device from a user.

[0011] According to a second aspect of the present invention, a reflecting system including one or more reflecting members for establishing a communication channel from a transmitting device to a receiving device is provided. Here, each reflecting member of the one or more reflecting members reflects a signal generated by the transmitting device. The reflecting system includes a communication unit configured to receive an instruction message including direction information of a reflecting member; an actuation unit configured to set the reflecting member to the

direction included in the instruction message.

[0012] According to a third aspect of the present invention, a transmitting device communicating with a receiving device via a communication channel established by reflecting systems including one or more reflecting members is provided. Here, each reflecting member of the one or more reflecting members reflects a signal generated by the transmitting device. The transmitting device includes a positioning unit

configured to obtain position information of the

transmitting device; a first communication unit

configured to transmit a request message including the position information to a server, and receive a

response message including a transmission direction of the signal from the server; and a second communication unit configured to transmit the signal to the

transmission direction included in the response message.

[ 0013 ] According to a fourth aspect of the present invention, a method in a server for establishing a communication channel from a transmitting device to a receiving device by controlling reflecting systems including one or more reflecting members is provided. Here, each reflecting member of the one or more

reflecting members reflects a signal generated by the transmitting device. The method includes receiving a request message from the transmitting device including position information of the transmitting device;

determining one or more reflecting members used for establishing the communication channel, a direction of each determined reflecting member, and a transmission direction of the transmitting device based on the position information of the transmitting device, location information of the reflecting members and position information of the receiving device; and transmitting the determined direction to corresponding reflecting member and the transmission direction to the transmitting device.

[ 0014 ] According to a fifth aspect of the present invention, a computer readable storage medium storing one or more programs for establishing a communication channel from a transmitting device to a receiving device by controlling reflecting systems including one or more reflecting members is provided. Here, each reflecting member of the one or more members reflects a signal generated by the transmitting device. The one or more programs causes a computer to function as: a database unit for storing location information of reflecting members; a communication unit for receiving a request message from the transmitting device

including position information of the transmitting device; and a determination unit for determining one or more reflecting members used for establishing the communication channel, a direction of each determined reflecting member, and a transmission direction of the transmitting device based on the position information of the transmitting device, the location information of the reflecting members and position information of the receiving device. The communication unit further transmits the determined direction to corresponding reflecting member and the transmission direction to the transmitting device.

[0015] Further objects and advantages of the present invention will be apparent from the following description of the exemplary embodiments of the invention as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0016] Fig. 1 shows a system according to an embodiment of the present invention;

[0017] Fig. 2 is a sequence diagram for

establishing a communication channel according to an embodiment of the present invention;

[0018] Fig. 3 is a block diagram of a management server according to an embodiment of the present invention;

[0019] Fig. 4 is a block diagram of a transmitting device according to an embodiment of the present invention; and

[0020] Fig. 5 is a block diagram of a reflecting system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] Fig. 1 shows an exemplary system according to an embodiment of the present invention. In Fig. 1, only one reflecting system 4 is indicated for

simplicity; however, a plurality of reflecting systems 4 is deployed. According to Fig. 1, a management server 1, a receiving device 2, a transmitting or client device 3 and reflecting systems 4 can

communicate with each other via a network 5. The network 5 is, for example, the Internet. However, the network 5 may be any another kind of data network.

Both wireline and wireless systems may be used for accessing the network 5. In Fig. 1, the management server 1, the receiving device 2 and the reflecting systems 4 use wireline access systems, such as DSL (Digital Subscriber Line) or PON (Passive Optical

Network) . However, a wireless system, such as WLAN (Wireless Local Area Network) or mobile access system specified by 3GPP, can be used to access the network 5. Since the transmitting device 3 is a mobile or portable device, the transmitting device 3 uses a wireless system to access the network 5.

[ 0022 ] In one embodiment, the transmitting device

3 is a UHTV camera, and transmits a UHTV signal to a receiving device 2 from a street using the high

frequency band, such as millimeter wave band or above. For example, the transmitting device 3 uses 57 to 63 GHz band. The receiving device 2 may be a media server for broadcasting. Since the transmitting device 3 is a portable device, line of sight is not always available between the transmitting device 3 and the receiving device 2.

[0023] In the present embodiment, to set up a communication path between the transmitting device 3 and the receiving device 2, the reflecting systems 4 are used. As shown in Fig. 5, each reflecting system 4 has one or more reflecting members 44, which can deflect or reflect the signal from the transmitting device 3. Each reflecting member 44 is installed on a high place, such as a roof or wall of a building or a pole, and a direction of the reflecting member 44 can be adjusted by an actuation unit 42. Thus, by

adjusting the direction of the reflecting member 44 such that a transmission signal from the transmitting device 3 is reflected toward the receiving device 2, a communication channel between the transmitting device 3 and the receiving device 2 can be established, and the transmitting device 3 can send the UHTV signal to the receiving device 2 using the established high capacity channel .

[0024] Depending on a position of the transmitting device 3, two or more reflecting members 44 can be used to establish the communication channel. The number of reflecting members 44 used for the channel is limited by the signal level at the receiving device 2, if no amplification mechanism is included. By deploying a multitude of reflecting systems 4, a communication channel connecting the transmitting and receiving devices can be easily established. To increase

flexibility of the channel set-up, the reflecting system 4 may be installed on or attached to a vehicle or otherwise mobile mechanism. Further, the reflecting members 44 is configured to be attachable to a

supporting member such as a pole shaped member to place the reflecting member in the high place and detachable from the supporting member. In this configuration, the reflecting system 4 can be carried by the vehicle, and the reflecting members 44 can be easily set in the high place for setting up the high capacity channel. This also increases flexibility of the channel set-up.

[ 0025 ] In the present embodiment, the management server 1 controls the reflecting systems 4 via the network 5. Further, in the present embodiment, a user of the transmitting device 3 or the receiving device 2 reserves the high capacity channel in advance. To reserve the channel, the user inputs reservation information to the management server 1 in advance. The reservation information includes a use period including a start time and an end time, position information of the receiving device 2 and approximate or estimated position information of the transmitting device 3.

Based on the reservation information, the management server 1 may assign a frequency and one or more

reflecting members 44 for setting up the channel between the receiving device 2 and the transmitting device 3.

[0026] If close frequencies are used for two channels in close region, interference may occur in each channel. Thus, the management server 1 assigns the frequency to the transmitting device 3 for its transmissions based on reservation information such that the interference from other communication in nearby channels can be reduced. More specifically, the management server 1 assigns the frequency to the channel between the receiving device 2 and the

transmitting device 3 based on frequencies assigned for other channels used in the same time window as the channel. Further, one or more reflecting members 44 assigned for the transmitting device 3 are selected based on the approximate position of the transmitting device 3, the position of the receiving device 2 and location information of each reflecting member 44.

[0027] Fig. 2 shows a sequence diagram for

establishing the high capacity channel between the transmitting device 3 and the receiving device 2. In step SI, when the high capacity channel is used as reserved, the transmitting device 3 sends a request message to the management server 1 via the network 5. The transmitting device 3 has a function to obtain its position, such as a GPS (Global Positioning System) receiver, and sends the position information of the transmitting device 3 in the request message.

[0028] Since the management server 1 obtains an exact position of the transmitting device 3 in step SI, the management server 1 checks, in step S2, whether the reserved reflecting members 44 for the transmitting device 3 are enough for establishing the high capacity channel. If the transmitting device 3 is close to the estimated position, the reserved reflecting members 44 are normally enough. However, if the transmitting device 3 is not close to the estimated position, the reserved reflecting members 44 may not be enough to establish the high capacity channel. If the reserved reflecting members 44 are not enough, the management server 1 reassigns the reflecting members 44 for the transmitting device 3. However, reassignment of reflecting members is not always possible because the required reflecting members 44 may be used for other channels. In this case the management server 1 may instruct the transmitting device 3 to change the position to another or estimated position.

[0029] In case the reserved reflecting members 44 are enough to establish the high capacity channel between the transmitting device 3 and the receiving device 2, the management server 1 calculates a

direction of each reflecting members 44 to establish the channel in step S2. If the reflecting system 4 on the vehicle is used, the management server 1 also calculates the location of the reflecting members 44 including a latitude, longitude and altitude. Further, the management server 1 calculates a transmission direction of the signal by the transmitting device 3. Further, the management server 1 calculates a receiving direction of the signal by the receiving device 2.

[0030] In step S3, the management server 1 sends a response message to the transmitting device 3 including the transmission direction. In step S4, the management server 1 sends an instruction message to each of the reflecting systems 4 used for establishing the channel. The instruction message includes a direction of the reflecting members 44. For the reflecting system 4 on the vehicle, the instruction message also includes a latitude, longitude and altitude. In step S5, the management server 1 sends an instruction message to the receiving device 2 including the receiving direction.

[0031] In step S6, each reflecting system 4 used for the channel configures a reflecting member 44 to direct the direction informed by the instruction message in response to a reception of the instruction message in step S4. Further, reflecting system 4 on the vehicle set the reflecting member 44 to place the latitude, longitude and altitude informed by the instruction message.

[0032] In step S7, the transmitting device 3 transmits the data to the transmission direction indicated by the response message, for example, by adjusting a direction of an antenna. Further, the receiving device 2 receives the signal reflected by one or more reflecting members 44 by adjusting an antenna to the receiving direction informed by the management server 1. The transmitting device 3 and the receiving device 2 have a sensor to determine the direction such as a magnetic sensor and an accelerometer .

[0033] In the above sequence, the management server 1 determines the receive direction of the

receiving device 2, and the receiving device 2 adjusts the antenna. However, in case the receiving device 2 is a fixed device, the receiving device 2 may be

configured to receive signals from all directions. In this case, the management server 1 does not need to determine the receive direction of the receiving device 2, and the receiving device 2 does not need to have a communication function via the network 5.

[0034] Fig. 3 shows a block diagram of the

management server 1 according to the present embodiment. According to Fig. 3, the management server 1 includes a communication unit 11, a determination unit 12, a database unit 13, a control unit 14, and a reservation unit 15.

[0035] The communication unit 11 handles

communications with the receiving device 2, the

transmitting device 3 and the reflecting systems 4 via the network 5. The determination unit 12 determines one or more reflecting members 44 used for establishing the communication channel. The determination unit 12 also determines a direction of each reflecting members 44 used for establishing the communication channel.

Further determination unit 12 determines a transmission direction of the transmitting device 3 and a receiving direction of the receiving device 2 based on the position information obtained from the transmitting device 3, location information of reflecting members 44 used for establishing the communication channel, and position information of the receiving device 2.

Further, the determination unit 12 determines a

frequency of the signal generated by the transmitting device 3 based on used frequencies for other

communication channels.

[ 0036 ] The database unit 13 stores information regarding the reflecting systems 4. More specifically, location information of each reflecting member 44 of each reflecting system 4 is stored in the database unit 13. Further, the database unit 13 has information about a total amount of rotation for a motor associated with a reflecting member 44. Here, the motor

associated with the reflecting member 44 is used to adjust the direction of the reflecting member 44. If the same motor is driven for a long duration of time or for short periods but frequently, it may shorten the lifetime of the motor. Thus, the management server 1 may use the total amount of rotation of each motor for determining the reflecting member 44 used for the channel such that the total amount of rotation of each motor is kept at a similar level.

[0037] The control unit 14 controls overall function in the management server 1. The reservation unit 15 manages reservation information. If the user enter reservation information including a use period of the channel, an estimated position of the transmitting device 3 and a position of the receiving device 2, the reservation unit 15 reserves one or more reflecting members 44 and a frequency for the communication channel based on the position information of the receiving device 2, estimated position information of the transmitting device 3 and a use period of the communication channel. The reserved reflecting members 44 and frequency are stored in the database unit 13.

[0038] The management server 1 may be realized by a computer, which executes the appropriate programs.

[0039] Fig. 4 shows a block diagram of the

transmitting device 3 according to the present

embodiment. According to Fig. 4, the transmitting device 3 includes a first communication unit 31, a second communication unit 32, a positioning unit 33, a sensor unit 34 and a control unit 35.

[0040] The first communication unit 31 handles communication with the management server 1 via the network 5. The second communication unit 32 handles communications with the receiving device 2 using for instance the millimeter wave band. The second

communication unit 32 can control a transmission

direction of the signal, and send the signal to the direction indicated in the response signal form the management server 1.

[0041] The positioning unit 33 obtains position information of the transmitting device 3, for example, by receiving the radio signal from the positioning system such as GPS. The sensor unit 34 obtains the direction of the transmitting device 3. This direction can be used to determine the transmission direction by the second communication unit 32. The control unit 35 controls overall function of the transmitting device 3.

[0042] Fig. 5 shows a block diagram of the

reflecting system 4 according to the present embodiment. According to Fig. 5, the reflecting system 4 includes a communication unit 41, an actuation unit 42, a control unit 43 and one or more reflecting members 44.

[0043] The communication unit 41 handles

communications with the management server 1 via the network 5. The actuation unit 42 has one or more motors corresponding to reflecting members 44, and adjusts a direction of each reflecting member 44. The control unit 43 controls overall function of the reflecting system 4. The reflecting member 44 reflects the radio signal generated by the transmitting device 3.

[0044] In the above embodiment, the user reserves the channel in advance. However, the invention is not limited to reserve the channel in advance. The

transmitting device 3 may send a request message to the management server 1 without the reservation. Since the management server 1 needs to identify the receiving device 2, the transmitting device 3 includes the

information for identifying receiving device 2 or position information of the receiving device 2 in the request message. In this case, the determination unit 12 of the management server 1 checks whether or not the channel can be established. If the channel can be established, the management server 1 controls the reflecting systems 4 accordingly. If the cannel can not be established, the management server 1 informs the transmitting device 3 accordingly.

[0045] Further, in the above embodiment, the transmitting device 3 is a mobile device, and the receiving device 2 is not the mobile device. However, the receiving device 2 may be the mobile device. In this case, both the receiving device 2 and the

transmitting device 3 obtain the position information, and send the position information to the management server 1.

[0046] Further, in the present embodiment, only one transmitting device 3 sends the signal to the receiving device 2. For example, in case of live broadcast of the sports event such as a marathon, a plurality of transmitting devices 3 such as TV cameras are used. In this case, the TV signal taken by a transmitting device 3 in the plurality of transmitting devices 3 selected by a user is broadcasted. Thus, the control unit 14 of the management server 1 may control the reflecting systems 4 in response to a user

selection of one transmitting device 3. More

specifically, upon receiving the selection signal of one transmitting device 3, the management server 1 determines a direction of each reflecting member 44, a transmission direction of the selected transmitting device 3 and a receiving direction of the receiving device 2, and sends messages for informing determined directions .

[0047] The invention may be achieved by a program, which realizes the functions of the above embodiments. Programs defining functions on the invention can be delivered to the management server 1 using non- transitory computer-readable storage media or via a network. It should be understood the invention may be implemented by software, hardware or a combination of software and hardware.

[0048] Many modifications and variations will be apparent to those of ordinary skill in the art. The present embodiments were chosen and described in order to best explain the principles of the invention. It should be understood that the present invention is not limited to the specific embodiments described in the specification.