JP5003842B2 - Channel setting pattern presentation program and channel setting pattern presentation apparatus - Google Patents

Description

  The present invention relates to a technique for presenting a broadcast channel setting pattern.

  2. Description of the Related Art Conventionally, a technique for recognizing a channel capable of receiving broadcast radio waves in a wireless communication system is known. On the other hand, a technique for recognizing a channel (that is, a free channel) that is not currently used and can be used by being assigned to a new communication request is also known. By detecting an empty channel, the empty channel can be reused efficiently.

  For example, a channel list distribution server is disclosed that enables a viewer to quickly present a broadcast program that a viewer wants to view using a channel list even when the broadcast reception areas are different.

  The channel list distribution server includes list group storage means for storing a channel list for each predetermined area. The channel list distribution server also includes list request receiving means for receiving position information and terminal reception channel information indicating at least one receivable channel from the broadcast receiving terminal as a list request. The channel list distribution server further includes correspondence list search means for searching for a channel list corresponding to the position information in the list group storage means. Then, when the terminal reception channel information is not included in the channel list corresponding to the position information, the nearest list search means for searching the channel list that includes the terminal reception channel information and is closest to the position indicated by the position information, The channel list distribution server is provided.

  In addition, the following techniques for improving the utilization efficiency of call channel resources in a mobile communication system having a plurality of base stations adjacent to each other in a manner that their coverage areas overlap each other are also disclosed. .

  The mobile communication system includes empty channel information sharing means for sharing use information of empty call channels of each base station between a plurality of adjacent base stations. Then, when any one of a plurality of adjacent base stations receives a channel assignment request signal for requesting assignment of a call channel from a mobile station existing at a position where the cover area overlaps, A base station is selected as follows. That is, a base station that assigns a call channel to the mobile station from a plurality of adjacent base stations based on use information of a free call channel shared by the free channel information sharing means. Selected.

There is also disclosed a base station control device that can provide information on an area where transmission is possible to a user and promote effective use of a line.
Specifically, the channel management means aggregates and manages the channels of each PHS (Personal Handy-phone System) base station based on control results such as call control and switching connection control of the call control means. Based on the management result, the display data control means counts the number of empty channels of a plurality of PHS base stations having a common display in the radio zone. Moreover, based on this total result, a display control part controls said common display, and alert | reports the radio | wireless zone which has an empty channel with respect to a user. Further, the terminal report control unit controls the PHS base station detected by the channel fluctuation base station detecting means and having a fluctuation in the number of empty channels, and information on the number of empty channels for the PHS terminals in each radio zone. Send.

Further, the following transmitter for performing stable unidirectional wireless communication is also disclosed.
The transmitter includes a receiving unit that sequentially scans a plurality of channels to identify an empty channel, a channel control unit that sets a channel of the transmitting unit to the identified empty channel, and data using the set channel. And a transmission unit for transmitting. The transmitter temporarily suspends data transmission during data transmission and monitors the free state of the channel used for the data transmission. If the channel is not empty, the transmitter sequentially scans the plurality of channels of the reception unit to identify other empty channels, and sets the channel of the transmission unit to the identified other empty channels, Data is transmitted using the other free channel. Therefore, the transmitter for unidirectional wireless communication can automatically identify an empty channel and transmit data, and automatically continue communication even when interference occurs during communication. Can do.

In addition to the processing using the detected free channel, there are various methods for detecting the free channel itself.
For example, the following techniques in a wireless communication system are known.

  The wireless communication system includes a plurality of wireless base stations that can use a plurality of wireless channels, and wireless terminals that are located in a wireless zone that is an area where the wireless base stations can communicate. The wireless communication system selects a wireless channel used for communication from a plurality of wireless channels between the wireless base station and the wireless terminal. Specifically, the wireless communication system measures a determination parameter of an empty channel, and selects a wireless channel to be used for communication from wireless channels in which the measurement result is less than or equal to a threshold value. To do. Here, the threshold value is determined by an empty channel determination function calculated based on the history of interference and the channel usage status. Therefore, the inefficiency that occurs when the idle channel determination level is fixed is removed in an autonomous and distributed manner.

Further, the following technique for searching for a free channel at high speed without increasing the amount of calculation or the circuit scale even when the number of channels in the system band is large is also disclosed.
That is, at the time of searching for an empty channel, a received signal from the antenna is sampled by a sampler at a sampling frequency that is less than twice the cutoff frequency of the band limiting filter. Then, from the output signal of the sampler, first empty channel information indicating empty channels in the return band is obtained by the detector. Also, the first free channel information is developed into second free channel information indicating a free channel in the system band by a free channel expander. Then, according to the second vacant channel information, the communication channel setting unit sets a communication channel for the transceiver.
JP 2007-67771 A JP 2002-271830 A JP-A-10-210529 JP 2000-196490 A JP-A-8-237732 JP 2007-19978 A

  With the widespread use of mobile terminals, it is considered that demand for services for distributing content to mobile terminals of users on the vehicle by wireless communication from a transmitter mounted on the vehicle is expected to increase in the future. However, in the content distribution service in such a vehicle, the following problems that are not assumed in the past are predicted.

  Although the situation regarding an empty channel, which is a channel that can be used for new communication, is affected by various factors, one of the main factors is where the receiver exists. Therefore, in the content distribution service in the vehicle, the situation regarding the empty channel may change as the vehicle moves.

  If the situation regarding the vacant channel changes, for example, a problem may occur that “it is difficult to continue the content distribution service while maintaining the quality using the same channel”. However, switching the distribution channel every time the situation regarding the free channel changes and requesting the service user to change the reception channel of the mobile terminal is inconvenient for the user and is preferable. is not. Therefore, it is desirable to reduce inconvenience to the user even if channel switching occurs during the service.

Accordingly, an object of the present invention is to present a channel setting pattern suitable for content distribution by radio in a vehicle in order to reduce the problem predicted as described above.
According to the first aspect of the disclosed technique, a channel setting pattern presentation program that causes a computer to execute a reference step, a narrowing step, and a presentation step is provided.

  The reference step is a step of referring to the storage means. The storage means associates each of the plurality of channels at each of the plurality of points with a point identifier for identifying a plurality of points on a route along which the vehicle moves and a channel identifier for identifying a plurality of channels of the broadcast radio wave. Remember the availability level.

  The narrowing-down step is a step of narrowing down a plurality of potentially possible channel setting patterns. Each of the plurality of channel setting patterns is a combination pattern in which the channel identifier is associated with each of the plurality of point identifiers representing the plurality of points. In the narrowing-down step, one or more channels in a channel identifier tuple in which the channel identifiers respectively associated with at least some of the plurality of point identifiers are arranged according to the order in the path of each point represented by each point identifier Narrowing is performed based on the distribution of identifiers and the availability level read by the reference step.

The presenting step is a step of presenting one or more channel setting patterns obtained as a result of the narrowing step.
According to the second aspect of the disclosed technique, there is provided a channel setting pattern presenting apparatus including the same storage means, narrowing-down means, and presenting means as in the first aspect.

  The narrowing-down means narrows down a plurality of potentially possible channel setting patterns by executing narrowing similar to the narrowing-down step of the first aspect. The presenting means presents one or more channel setting patterns obtained as a result of narrowing by the narrowing means.

  According to the disclosed technology, in any aspect, an appropriate channel setting pattern is presented based on the distribution of channel identifiers and the availability level. Therefore, a transmitter that performs content distribution operates according to the presented channel setting pattern, so that it is possible to provide a content distribution service in a vehicle without imposing a heavy burden on the user.

It is a block diagram of the broadcast system in 1st Embodiment. It is a block diagram which shows the structure of a local TV transmitter. It is a hardware block diagram of a local TV transmitter. It is a block diagram of the computer which implement | achieves a channel setting pattern presentation apparatus and a memory | storage device. It is a figure which shows the example of the empty channel measurement information table which memorize | stores empty channel measurement information. It is a figure which shows the example of the point information table which memorize | stores point information. It is a figure which shows the example of the operation information table which memorize | stores operation information. It is a figure which shows the example of the influence range information table which memorize | stores influence range information. It is a flowchart of the empty channel search process in 1st Embodiment. It is a flowchart of the empty channel search process in the modification of 1st Embodiment. It is a flowchart of the pattern presentation process in 1st Embodiment. It is a figure which shows the example of the expand | deployed path | route information table. It is a figure which shows the 1st example of the expand | deployed empty channel information table. It is a figure which shows the 2nd example of the expand | deployed empty channel information table. It is a figure which shows the example of a channel setting pattern table. It is a figure which shows the 1st example of a display. It is a figure which shows the 2nd example of a display. It is a figure which shows the 3rd example of a display. It is a figure which shows the 4th example of a display. It is a flowchart of the pattern determination process in 2nd Embodiment. It is a figure explaining the "deemed continuous empty area" defined in 2nd Embodiment.

Hereinafter, the first embodiment and a modification of the first embodiment will be described with reference to FIGS. 1 to 15D, and the second embodiment will be described with reference to FIGS. 16 to 17.
FIG. 1 is a configuration diagram of a broadcasting system in the first embodiment. 1, a broadcasting system 100 includes a local TV (television) transmitter 110, a TV-equipped mobile terminal 140, and a channel setting pattern presentation device 150.

  The local TV transmitter 110 is loaded on a vehicle that moves along a specific route such as a bus, a train, or a regular route ship, and performs local TV broadcasting in the vehicle. The local TV transmitter 110 includes a plurality of antennas (only antennas 111 and 112 are representatively shown in FIG. 1), a TV transmission device 113, a TV reception device 114, and a content storage unit 115.

  The plurality of antennas include antennas for transmitting and receiving TV broadcasts. There may also be an antenna for wireless communication with the channel setting pattern presentation device 150. The TV transmission device 113 transmits radio waves for TV broadcasting. The TV receiver 114 performs an empty channel search process which will be described later with reference to FIG. The content storage unit 115 stores content data distributed by TV broadcasting.

  The TV-equipped mobile terminal 140 is a terminal such as a mobile phone held by a passenger of a vehicle on which the local TV transmitter 110 is loaded, and has a function of receiving TV broadcasts. Although only one mobile terminal 140 with TV is shown in FIG. 1, there may be a plurality of mobile terminals 140 with TV. The TV-equipped mobile terminal 140 includes a plurality of antennas (only antennas 141 and 142 are shown as representative in FIG. 1), a TV receiver 143, a display 144, and a speaker 145.

  The plurality of antennas include antennas for receiving TV radio waves. In addition, for example, if the TV-equipped mobile terminal 140 is a mobile phone, the plurality of antennas include a call antenna. The TV receiver 143 is an apparatus that receives TV broadcast radio waves via an antenna. The display 144 displays an image of the content received by the TV receiving device 143, and the speaker 145 outputs the sound of the content received by the TV receiving device 143.

  The channel setting pattern presentation device 150 presents a channel setting pattern that is a combination pattern of where and which channel the local TV transmitter 110 uses to broadcast. The channel setting pattern presentation device 150 may be loaded in the same vehicle as the local TV transmitter 110 or the mobile terminal 140 with TV, as long as data communication with the local TV transmitter 110 is possible. It may be located away from the vehicle.

  The channel setting pattern presentation device 150 is connected to a storage device 151 that stores various information used for determining a channel setting pattern to be presented. As will be described later, the storage device 151 stores data collected from various devices.

  Although the specific vehicle type and the standard of TV broadcasting adopted in the broadcasting system 100 are arbitrary, the first embodiment will be described on the assumption that one seg broadcasting is performed in the bus. Further, it is assumed that channel setting pattern presentation device 150 is loaded in the same bus as local TV transmitter 110.

  One-segment broadcasting is terrestrial digital broadcasting and is mainly performed for mobiles such as mobile phones. In ISDB-T (Integrated Services Digital Broadcasting for Terrestrial), which is a standard used in terrestrial digital broadcasting, 50 physical channels of channel 13 to channel 62 are provided. The frequency band of each physical channel is divided into 13 segments. One-segment broadcasting is performed using one central segment among the 13 segments.

  In Japan, broadcasting stations licensed under the Radio Law generally perform one-segment broadcasting. However, if weak radio waves that do not require a license under the Radio Law are used, one-segment broadcasting from transmitters other than broadcast stations is legal. Although the range in which weak radio waves can be received is limited, there are advantages to using weak radio waves. For example, if weak radio waves are used, it is possible to provide a content distribution service in which merchandise information is freely broadcast in the store according to the convenience of the store without obtaining a license.

  Hereinafter, one-segment broadcasting using weak radio waves is referred to as “local broadcasting” for convenience. The TV transmitter 113 provided in the local TV transmitter 110 of FIG. 1 is a local broadcast transmitter. Although the radio wave transmitted from the TV transmission device 113 via the antenna is weak, the weak radio wave is sufficient for broadcasting intended for passengers on the bus on which the local TV transmitter 110 is loaded. For example, the local TV transmitter 110 may broadcast content such as store advertisements along the bus route for passengers. The content to be broadcast is stored in the content storage unit 115.

  Here, in a certain area, it is assumed that, for example, channel 13 out of 50 physical channels (hereinafter simply referred to as “channels”) of ISDB-T is used by a licensed broadcasting station. Then, in order to perform local broadcasting with weak radio waves in the area, it is necessary to use an empty channel other than the channel 13.

  In another adjacent area, the channel 13 is not used by the broadcasting station, and the channel 14 may be used instead. That is, the same channel 13 may be an empty channel or not an empty channel depending on the region. Therefore, when the bus moves across a plurality of regions, it is desirable that the TV transmission device 113 performs broadcasting using an appropriate channel according to the location where the bus is traveling.

  In the following, “empty channel” refers to a channel that provides sufficient reception quality in local broadcasting. In other words, an empty channel at a certain location refers to a channel at which the reception level of radio waves from other broadcast stations or other noise sources is so low that it can be ignored.

  Since local broadcast radio waves are weak, they are also susceptible to noise from electromagnetic waves generated by surrounding electrical equipment. Of course, which channel is susceptible to noise from the surrounding environment also changes as the bus moves. Therefore, it is desirable that the TV transmission device 113 performs broadcasting using a channel corresponding to the current location of the bus, not only from the viewpoint of the channel used by the broadcasting station but also from the viewpoint of the surrounding environment.

  However, in a local broadcast on the bus, if the channel used for the broadcast is changed many times as the bus travels, a passenger who is a user of the content distribution service is burdened with a change operation of the reception channel. Therefore, from the viewpoint of passenger convenience, it is desirable that the number of channel changes be small. Further, in order to avoid frequently requesting the passenger to change the reception channel, it is desirable that the channel change interval is longer.

  Therefore, the first embodiment makes it possible to select an appropriate channel so as to reduce the burden on passengers and to increase the time during which sufficient reception quality can be obtained while traveling on a bus. For the purpose.

  In order to achieve the object, in the first embodiment, the channel setting pattern presentation device 150 narrows down a number of potentially possible channel setting patterns and presents one or more appropriate channel setting patterns obtained as a result of the narrowing down. To do. Then, the local TV transmitter 110 performs local broadcasting according to the presented channel setting pattern. As will be described in detail later, each “channel setting pattern” is a combination pattern representing how to switch channels used for local broadcasting as the bus travels.

  In the following, first, the configuration of the local TV transmitter 110 and the channel setting pattern presentation device 150 will be described with reference to FIGS. 2 to 4, and the creation of an empty channel measurement information table will be described with reference to FIGS. To do. Thereafter, processing for presenting an appropriate channel setting pattern will be described with reference to FIGS. 11 to 15D.

FIG. 2 is a block diagram showing the configuration of the local TV transmitter 110.
The local TV transmitter 110 includes a GPS (Global Positioning System) / WLAN (Wireless Local Area Network) / BT (Bluetooth) processing unit 116 (Bluetooth is a registered trademark). The local TV transmitter 110 includes a TV transmission / reception unit 117 and a communication RF (Radio Frequency) processing unit 118. The local TV transmitter 110 further includes a CPU (Central Processing Unit) / DSP (Digital Signal Processor) 119 and an RTC (Real Time Clock) 120. The CPU / DSP 119 includes a general-purpose CPU and a DSP for performing specific processing such as wireless communication including broadcasting.

  Furthermore, the local TV transmitter 110 includes an AIU (Audio Interface Unit) 121, a speaker 122, a microphone 123, a numeric keypad 124, a display 125, and a memory area 126.

  Each of the GPS / WLAN / BT processing unit 116, the TV transmission / reception unit 117, and the communication RF processing unit 118 includes an antenna, is connected to the CPU / DSP 119, and operates according to control by the CPU / DSP 119.

  The GPS / WLAN / BT processing unit 116 implements a GPS function for specifying the position of the local TV transmitter 110, and communicates with other devices (for example, the channel setting pattern presentation device 150) using the WLAN or BT. To realize.

  The TV transmission / reception unit 117 corresponds to the TV transmission device 113 and the TV reception device 114 of FIG. The TV transmission / reception unit 117 realizes a function of transmitting a radio wave for local broadcasting and a function of receiving a radio wave for an empty channel search process described later.

The communication RF processing unit 118 realizes a function of performing wireless communication with other devices such as the channel setting pattern presentation device 150 according to an appropriate wireless communication standard.
The CPU / DSP 119 generates a CPU clock based on the time of the RTC 120 and operates according to the CPU clock. Data used by the CPU / DSP 119 for various processes is stored in the memory area 126. The memory area 126 includes, for example, both a nonvolatile storage device and a volatile storage device for a work area. The nonvolatile storage device also functions as the content storage unit 115 in FIG.

  The CPU / DSP 119 is connected to the numeric keypad 124, receives an input from the numeric keypad 124, and operates according to the input. The local TV transmitter 110 may include other input devices such as a keyboard and a pointing device instead of or together with the numeric keypad 124. The display 125 is also connected to the CPU / DSP 119, and the CPU / DSP 119 controls the display 125 so as to display processing results and messages to the operator.

  The speaker 122 and the microphone 123 are connected to the CPU / DSP 119 via the AIU 121. The CPU / DSP 119 can receive an input from the microphone 123 via the AIU 121. The CPU / DSP 119 may operate according to an input from the microphone 123. Further, the CPU / DSP 119 may control the speaker 122 so as to audibly output a processing result or a message to the operator via the AIU 121.

FIG. 3 is a hardware configuration diagram of the local TV transmitter 110.
As shown in FIG. 3, the local TV transmitter 110 includes a CPU / DSP 119, an RTC 120, a TV receiver 114, and a TV transmitter 113. The local TV transmitter 110 further includes a ROM (Read Only Memory) 127, a RAM (Random Access Memory) 128, a nonvolatile storage device 129, and an external interface 130. 3 are connected to each other via a bus 131.

  The CPU / DSP 119 controls the entire local TV transmitter 110 by operating in accordance with a program stored in the ROM 127 or the nonvolatile storage device 129 while using the RAM 128 as a work area.

  Note that the program may be provided by being stored in various types of storage media (not shown) such as an optical disc such as a CD (Compact Disc) and a DVD (Digital Versatile Disk), a magneto-optical disc, a magnetic disc, and a nonvolatile semiconductor memory. Good. Then, the program may be read from the storage medium by a storage medium driving device (not shown) and copied to the nonvolatile storage device 129. Alternatively, the program may be downloaded from the network to the nonvolatile storage device 129.

  The relationship between FIG. 1 and FIG. 3 is as follows. The TV transmitter 113 and TV receiver 114 of FIG. 1 are also shown in FIG. Further, the content storage unit 115 in FIG. 1 is specifically realized by the ROM 127 or the nonvolatile storage device 129 in FIG. The nonvolatile storage device 129 may be a nonvolatile RAM such as a flash memory or a magnetic storage device such as a hard disk device.

  The relationship between FIG. 2 and FIG. 3 is as follows. The CPU / DSP 119 and RTC 120 of FIG. 2 are also shown in FIG. The AIU 121 in FIG. 2 is an example of the external interface 130 in FIG. 3 includes an interface not shown in FIG. 2 for connecting the numeric keypad 124 and the display 125 of FIG. 2 to the CPU / DSP 119.

  Specifically, the memory area 126 in FIG. 2 is realized by the ROM 127, the RAM 128, and the nonvolatile storage device 129 in FIG. 2 is realized by the TV transmission device 113 and the TV reception device 114 of FIG. In FIG. 3, portions corresponding to the GPS / WLAN / BT processing unit 116 and the communication RF processing unit 118 of FIG. 2 are omitted.

FIG. 4 is a configuration diagram of a computer that implements the channel setting pattern presentation device 150 and the storage device 151.
The channel setting pattern presentation device 150 and the storage device 151 in FIG. 1 can be realized by a general-purpose computer 160 as shown in FIG. The computer 160 includes a CPU 161, a ROM 162, a RAM 163, a communication interface 164, an input device 165, an output device 166, a storage device 167, and a drive device 168 for the portable storage medium 170. These units included in the computer 160 are connected to each other via a bus 169.

  The computer 160 is connected to the network 171 via the communication interface 164. The network 171 is an arbitrary network such as a LAN (Local Area Network) or the Internet. A local TV transmitter 110 may be connected to the network 171. The local TV transmitter 110 can communicate with the computer 160 that implements the channel setting pattern presentation device 150 via the network 171. A part of the network 171 may be a WLAN, for example. A part of the network 171 may include a wired network.

  The CPU 161 loads the program into the RAM 163 and executes the program while using the RAM 163 as a work area, thereby causing the computer 160 to function as the channel setting pattern presentation device 150 in FIG. That is, the computer 160 functions as the channel setting pattern presentation device 150 by the CPU 161 executing the processing of FIG. 11 according to the program.

  Specifically, the CPU 161 functions as a narrowing-down unit that narrows down a plurality of potentially possible channel setting patterns. Further, the CPU 161 functions as a presentation unit that presents one or more channel setting patterns obtained as a result of narrowing down in cooperation with the output device 166 or the communication interface 164.

  A program that causes the computer 160 to function as the channel setting pattern presentation device 150 may be stored in advance in the ROM 162 or the storage device 167. Alternatively, the program may be provided from the program provider 172 via the network 171 and stored in the storage device 167.

  Alternatively, the program may be stored in the portable storage medium 170, loaded from the portable storage medium 170 set in the driving device 168 into the RAM 163, and executed by the CPU 161. As the portable storage medium 170, various types of storage media such as an optical disk such as a CD and a DVD, a magneto-optical disk, a magnetic disk, and a nonvolatile semiconductor memory can be used.

  The input device 165 is a pointing device such as a mouse or a keyboard. The output device 166 is a display device such as a liquid crystal display, but may include a speaker or a printer. The storage device 167 may be a magnetic disk device such as a hard disk device or another type of storage device. The storage device 167 can implement the storage device 151 of FIG.

  In some embodiments, the local TV transmitter 110 may also serve as the channel setting pattern presentation device 150. For example, the CPU / DSP 119 of the local TV transmitter 110 in FIG. 3 functions as the channel setting pattern presentation device 150 in FIG. 1 by loading the program stored in the ROM 127 or the nonvolatile storage device 129 into the RAM 128 and executing it. May be.

  When the local TV transmitter 110 also serves as the channel setting pattern presentation device 150, for example, the nonvolatile storage device 129 in FIG. 3 functions as the storage device 151 in FIG. In this case, the local TV transmitter 110 and the channel setting pattern presentation device 150 do not need to communicate via a network. Therefore, in FIG. 2, the communication RF processing unit 118 may be omitted, and the communication function by WLAN or BT may be omitted among the functions of the GPS / WLAN / BT processing unit 116.

  When the local TV transmitter 110 also serves as the channel setting pattern presentation device 150, the CPU / DSP 119 functions as a narrowing means for narrowing down a plurality of potentially possible channel setting patterns. Further, the CPU / DSP 119 functions as a presentation unit that presents one or more channel setting patterns obtained as a result of narrowing down in cooperation with the display 125 or the speaker 122.

  The configuration of the broadcast system 100 has been described above with reference to FIGS. The mobile terminal 140 with TV in FIG. 1 is, for example, a known mobile phone with a one-segment function, and a detailed description thereof will be omitted.

  Next, the empty channel search process will be described. The empty channel search process is a process for acquiring empty channel measurement information used by the channel setting pattern presentation device 150 to present an appropriate channel setting pattern. In the following, various information related to the empty channel search process will be described first, and then the contents of the process will be described.

  FIG. 5 is a diagram illustrating an example of an empty channel measurement information table 201 that stores empty channel measurement information. The free channel measurement information table 201 is stored in the storage device 151 of FIG.

  The free channel measurement information is added to and stored in the free channel measurement information table 201 by the process shown in FIG. The free channel measurement information is information that associates a “clearness level” with a point ID and a channel ID.

  Here, the point ID is a specific example of a point identifier for identifying a plurality of points on the route on which the bus travels. The channel ID is a specific example of a channel identifier that identifies a plurality of channels of broadcast radio waves that may be used for local broadcasting.

  In the following description, the “clear level” of the channel X at a certain point is a level representing the availability at the point of the channel X, in other words, at the point of local broadcasting using the channel X. This is a level representing reception quality. If a licensed broadcasting station is performing one-segment broadcasting using channel X, or if channel X is greatly affected by the surrounding environment, and the local broadcasting is performed using channel X, the reception quality is Expected to be low. Therefore, in this case, the clear level of channel X is low. Conversely, when channel X is not used for one-segment broadcasting by a broadcasting station and there are no nearby noise sources that have a large influence on channel X, the clear level of channel X is high.

  In other words, if the reception strength of the channel X (more precisely, the reception strength of the central segment used for local broadcasting, which is one-segment broadcasting by the weak radio wave among the 13 segments of the channel X) is strong, The clear level of X is low. Conversely, if the reception intensity of channel X is weak, the clear level of channel X is high.

In the first embodiment, the clear level corresponding to good reception quality is represented as “3”, the clear level corresponding to normal reception quality is represented as “2”, and the clear level corresponding to poor reception quality is represented as “1”. ". The above “good”, “normal”, and “poor” are defined in advance by a predetermined standard according to the embodiment. For example, the clear level can be defined as follows using _two threshold values T ₁ and T ₂ (T ₁ <T ₂ ).

• When the reception intensity of the channel X is less than T _1, the clear level is 3.
• When the reception intensity of the channel X is less than above T ₁ T _2, clear level is 2.
• When the reception intensity of the channel X is T ₂ or more, clear level is 1.

  In the first embodiment, the clear level is represented by discrete values of 1 to 3, but, of course, the specific definition of the clear level varies depending on the embodiment. For example, the clear level may be represented by a discrete value of two stages, a discrete value of four or more stages, or a continuous value. For example, the continuous reception intensity itself can be used instead of the clear level.

  The free channel measurement information stored in the free channel measurement information table 201 in FIG. 5 is information that associates the clear level of each channel at each point with the point ID and the channel ID. In order to be able to present an appropriate channel setting pattern even when the clear level fluctuates depending not only on the location but also on the time zone, the empty channel measurement information of the first embodiment uses the clear level as well as the time. Corresponds.

  Specifically, a unique measurement number (hereinafter referred to as “measurement No”) is assigned to each row of the free channel measurement information table 201 of FIG. Each row represents empty channel measurement information corresponding to measurement performed collectively at one point.

  Each row includes a “point ID” indicating a point where the measurement is performed, and also includes a “measurement time” when the measurement is performed. Each row includes a set of channel ID and clear level for each of a plurality of channels. In the first embodiment, the clear level of each channel at each point is associated with the point ID and the channel ID, and also associated with the measurement time in the above-described format.

  As described above, in ISDB-T, there are 50 channels 13 to 62, but depending on the embodiment, each row of the empty channel measurement information table 201 includes 50 sets of channel IDs and clear levels. It does not have to be included. For example, in any area where a bus is operating, if one-segment broadcasting from a broadcasting station can be received with sufficient reception quality on at least five channels, the measurement target is 45 (= 50-5) at any point. It may be less than the set. In this case, assuming that M = 45 in FIG. 5, the empty channel measurement information table 201 may have a format in which each row can include a maximum of 45 pairs of channel IDs and clear levels.

  In the example of FIG. 5, the row where the measurement number is “1” represents the result of the measurement performed at 9 o'clock at the point where the point ID is “P1” (hereinafter referred to as “point P1”). Yes. This row includes a set of channel ID “13” and clear level “3”, a set of channel ID “14” and clear level “2”, and the like. The number of sets of channel ID and clear level included in this row depends on the number of one-seg broadcasting channels that can be satisfactorily received at the point P1.

  For example, suppose that it is known in advance that a one-segment broadcast from a broadcasting station can be received with good reception quality at a specific seven channels at the point P1. In other words, it is assumed that the reception strengths of the specific seven channels are known in advance. In this case, the specific seven channels are obviously unsuitable for use in local broadcasting, without measuring the clear level. Therefore, in this case, the row whose measurement number is “1” may include only 43 (= 50−7) pairs of channel IDs and clear levels. Of course, measurement may be performed for all 50 channels including the specific seven channels.

Similarly, the other rows in FIG. 5 include a unique measurement number, a point ID, and a measurement time, and further include a plurality of sets of channel IDs and clear levels.
For example, in order to be able to present an appropriate channel setting pattern even when the clear level varies depending on the day of the week, the free channel measurement information table 201 further includes a column for measurement day of the week. It may be. Similarly, when the clear level fluctuates according to the weather, the free channel measurement information table 201 may have a column for recording the weather. On the other hand, when the clear level fluctuation caused by the time zone is small enough to be ignored, the empty channel measurement information table 201 may not include the measurement time column.

Next, various types of information related to the above point ID will be described with reference to FIGS.
FIG. 6 is a diagram illustrating an example of the spot information table 202 that stores spot information. The point information table 202 is created in advance and stored in the storage device 151 of FIG.

  The point represented by the point ID is a point representing a two-dimensionally expanding area. The point information is information that associates each point ID with an area. In the first embodiment, each area is a rectangle, and the area is defined by two points on a diagonal line of the rectangle. Hereinafter, for convenience, two points on the diagonal of the rectangle are referred to as “start point” and “end point”.

  For example, in the example of FIG. 6, the point represented by the point ID of “P1” is representative of the starting point of north latitude 35.531328 degrees and east longitude 139.669689 degrees and north latitude 35.5561522 degrees and east longitude 139.716182 degrees. This is a rectangular area defined by the end point of. As described above, in the point information table 202 in FIG. 6, an area is defined by point information that associates two pairs of latitude and longitude with a point ID, and the correspondence between the area and the point is managed.

  In the first embodiment, it is assumed that the point represented by the point ID, that is, the point representing the area is specifically the center point of the rectangular area. In some embodiments, points other than the center point may represent the area. In the first embodiment, the areas are defined so as not to overlap with each other. However, the areas may overlap in some embodiments.

  Furthermore, in some embodiments, the shape of the area may be a circle, an ellipse, a triangle, another polygon, or the like. For example, in an embodiment where a circular area is employed, the point information may include the latitude and longitude of the center point represented by the point ID and the radius of the circle.

  Each area is desirably a range in which the situation of the free channels can be considered to be the same or a smaller range. The reason is that the size of each area corresponding to each point ID defines the granularity of the channel setting pattern. If the situation regarding an empty channel greatly differs between two points in the area corresponding to one point ID, the possibility that an appropriate channel setting pattern is not presented increases. Therefore, it is preferable to determine an appropriate size of the area from a preliminary experiment, for example.

  The sizes of the plurality of areas may be different from each other or the same. For example, in an area where there are many artifacts that can be a source of noise, there is a possibility that various artifacts may be affected by a large number of artifacts. is there. Therefore, a relatively small area may be defined in an area where there are many artifacts. On the other hand, on a road with few artifacts, the situation of an empty channel rarely changes rapidly as the bus travels, so a relatively large area may be defined.

Hereinafter, in the description of the first embodiment, it is assumed that an area having an appropriate size is defined.
FIG. 7 is a diagram illustrating an example of an operation information table 203 that stores operation information. The operation information table 203 is also created in advance and stored in the storage device 151 of FIG. In the first embodiment, since it is assumed that the bus operates according to the same timetable every day, the operation information table 203 includes a “route ID” column, a “passing point ID” column, and a “point passing scheduled time” column. Including.

  The route ID in the first embodiment is an identifier for identifying a bus operation route (that is, a route; hereinafter, also simply referred to as “route”) and also identifying a plurality of flights running on the same route.

  For example, the operation information table 203 in FIG. 7 includes four rows with a route ID “1”. These four lines indicate that the route identified by the route ID “1” is “a route that departs from the point P1 and arrives at the point P8 via the points P2 and P7”. These four lines indicate that the flight identified by the route ID “1” “departs from point P1 at 9:00, passes through point P2 at 9:00:50, and passes through point P7 at 9:00 It also indicates that the flight is scheduled to pass at 20 minutes and 20 seconds and arrive at the point P8 at 9: 3: 20.

  As described above, in the first embodiment, the route ID is a set of a point ID of a passing point (including a starting point and an ending point of the operating route) on the bus operating route and a scheduled time when the bus passes the passing point. Each flight is defined by a plurality of lines that correspond to. In the example of FIG. 7, a part of two operation routes identified by route IDs “1” and “2” (that is, between the points P1 and P2) is common. Thus, some of the plurality of operation routes may overlap.

  Note that the format of the operation information table 203 may be changed as appropriate in accordance with the way of bus operation. For example, when the bus operates according to different timetables on weekdays (Monday to Friday) and holidays (Saturday and Sunday), the operation information table 203 may further include a flag column for distinguishing between weekdays and holidays. .

FIG. 8 is a diagram illustrating an example of the influence range information table 204 that stores the influence range information. The influence range information table 204 is also created in advance and stored in the storage device 151 of FIG.
The influence range information is information that associates time and distance with the point ID. Specifically, the influence range information table 204 includes a “passage point ID” column, a “reception influence time” column, and a “reception influence distance” column.

  As described with reference to FIG. 6, the point represented by each point ID is a point representing an area having a two-dimensional extent. The influence range information is information representing the area size by time and distance.

  From the above assumption that the area is defined to an appropriate size, the environment that affects the reception of local broadcasts while the bus travels in one area (for example, one-seg broadcast radio waves from broadcast stations, other It can be considered that the reception intensity of radio waves radiated from an artificial object is almost constant. Therefore, the travel time and travel distance of each area are also the travel time or travel distance in which the environment where the influence on the reception of the local broadcast is almost constant continues.

Therefore, in the first embodiment, as shown in FIG. 8, the width of each area is represented by time and distance by the “reception influence time” column and the “reception influence distance” column.
For example, in FIG. 8, the reception influence time and the reception influence distance of the row having the passage point ID “P1” are 25 seconds and 250 m, respectively. This line takes 25 seconds for the bus to travel in the area defined by the line whose point ID is “P1” in the point information table 202 of FIG. 6, and in that 25 seconds the bus follows the route within the area. It shows that the vehicle travels a distance of 250 m (that is, a journey). In other words, the same situation regarding the empty channel continues for 25 seconds while the bus is traveling in the area represented by the point P1, during which the bus travels 250 meters in the area. Run.

  In the example of FIG. 8, the ratio between the reception influence time and the reception influence distance is constant by chance. However, the ratio of the reception influence time and the reception influence distance may be different for each point ID depending on road conditions such as traffic jams.

  Further, both the influence range information table 204 in FIG. 8 and the point information table 202 in FIG. 6 are tables that store information that associates other information with the point ID. It may be grouped into two tables.

The various information related to the empty channel search process has been described above with reference to FIGS. 5 to 8. Next, the empty channel search process will be specifically described.
FIG. 9 is a flowchart of empty channel search processing in the first embodiment. The vacant channel search process includes a process of measuring a clear level by receiving broadcast radio waves on a plurality of channels at each of a plurality of points on the route.

  In the first embodiment, when the bus operates normally, the local TV transmitter 110 loaded on the bus executes the process of FIG. Specifically, the process of FIG. 9 is started immediately before the bus departs from the start point of a certain operation route.

  In step S101, the CPU / DSP 119 (see FIGS. 2 to 3) of the local TV transmitter 110 (see FIGS. 1 to 3) determines the point ID of each measurement point on the route on which the bus is to travel from now on. Area information is acquired and stored in the memory area 126 of FIG. The “measurement point” is a point at which measurement is performed to check the status of an empty channel, and specifically, is a point represented by the point ID described with reference to FIGS.

  For example, before the bus departs, a route ID for identifying a route on which the bus is scheduled to travel and a flight are input from the bus driver via the numeric keypad 124 of FIG. The CPU / DSP 119 receives the input route ID from the numeric keypad 124.

  Then, the CPU / DSP 119 displays a plurality of point IDs associated with the input route IDs in the operation information table 203 in the storage device 151 via the channel setting pattern presentation device 150 in FIG. 1 (see FIG. 7). Read from.

  As indicated by thick arrows in FIG. 1, the local TV transmitter 110 and the channel setting pattern presentation device 150 are connected by WLAN, BT, or other wireless communication network, and can exchange data with each other. it can. Therefore, the CPU / DSP 119 can acquire data from the storage device 151 by communicating with the channel setting pattern presentation device 150 via the GPS / WLAN / BT processing unit 116 or the communication RF processing unit 118 of FIG. it can. Similarly, the CPU / DSP 119 can write data in the storage device 151 by communicating with the channel setting pattern presentation device 150 via the GPS / WLAN / BT processing unit 116 or the communication RF processing unit 118.

  For example, when the route ID “1” is input, in step S101, the CPU / DSP 119 causes “P1” and “P2” associated with the route ID “1” from the operation information table 203 of FIG. , “P7” and “P8” are acquired. The CPU / DSP 119 stores the acquired four spot IDs in the memory area 126.

  In the first embodiment, the CPU / DSP 119 also acquires a scheduled point passage time corresponding to each point ID from the operation information table 203 for the convenience of processing in step S103 described later. Then, the CPU / DSP 119 stores the acquired spot IDs in the memory area 126 in order according to the scheduled spot passing time. According to the example of FIG. 7, “P1” is the first, “P2” is the second, “P7” is the third, and “P8” is the fourth.

  Then, the CPU / DSP 119 stores the area information of the four areas represented by the acquired four point IDs “P1”, “P2”, “P7”, and “P8” in the storage device 151 in FIG. Is acquired from the point information table 202. The area information is also acquired through communication with the channel setting pattern presentation device 150 via the GPS / WLAN / BT processing unit 116 or the communication RF processing unit 118. The CPU / DSP 119 stores the acquired area information in the memory area 126.

  In step S102, the CPU / DSP 119 activates the tuner. That is, the CPU / DSP 119 activates the reception function (that is, the function realized by the TV reception device 114) of the TV transmission / reception unit 117 in FIG. 2 by activating the TV reception device 114 shown in FIGS.

  Subsequent steps S103 to S106 are repeatedly executed. Further, the CPU / DSP 119 continues to monitor the current location of the bus on which the local TV transmitter 110 is loaded by the GPS function of the GPS / WLAN / BT processing unit 116 of FIG. 2 while repeating the processing of steps S103 to S106. For example, the CPU / DSP 119 controls the GPS / WLAN / BT processing unit 116 to perform positioning at a predetermined interval (for example, every 1 second) that is sufficiently shorter than the reception influence time (see FIG. 8) of any area. May be.

  In step S103, the CPU / DSP 119 determines whether the bus has arrived at the next measurement point based on the current position of the bus. Step S103 is repeated until the CPU / DSP 119 determines that the bus has arrived at the next measurement point. If the CPU / DSP 119 determines that the bus has arrived at the next measurement point, the process proceeds to step S104.

  For example, when four point IDs “P1”, “P2”, “P7”, and “P8” are acquired in step S101 corresponding to the route ID “1” as described above, step S103 is executed for the first time. Specifically, the following processing is performed.

  As described above, the four spot IDs “P1”, “P2”, “P7”, and “P8” are ordered and stored in the memory area 126, and the first spot ID is “P1”. Therefore, the “next measurement point” when step S103 is executed for the first time is the point P1. In step S101, since the area information represented by the point P1 is obtained, the CPU / DSP 119 calculates the latitude and longitude of the point P1, which is the center point of the rectangle defined by the area information, based on the area information. can do.

  9 is started immediately before the bus departs, so when step S103 is executed for the first time, the bus is located at the starting point P1. Therefore, by comparing the calculated latitude and longitude of the point P1 with the latitude and longitude of the current position recognized as a result of monitoring by the GPS / WLAN / BT processing unit 116, the CPU / DSP 119 indicates that the current bus is “next”. It is recognized that it is located at the point P1, which is a “measurement point”. Therefore, the process proceeds to step S104.

A specific example in which step S103 is executed again after steps S104 to S106 are executed will be described later.
In step S104, the TV receiver 114 measures the clear level for each channel to be searched according to the control by the CPU / DSP 119. Here, the search target channel is predetermined according to each measurement point.

  For example, as illustrated with reference to FIG. 5, it is assumed that the one-segment broadcasting from the broadcasting station can be received with good reception quality at the point P1 through the specific seven channels. In this case, the search target at the point P1 may be 43 channels other than the specific seven channels among the 50 channels. Of course, depending on the embodiment, all 50 channels may be searched.

In step S104, the TV receiver 114 measures the radio wave reception intensity of each channel. Then, CPU / DSP119 is measured numerical, and using the threshold _{T 1} and _{T 2} was illustrated with respect to FIG. 5, to determine the clearing level for each channel.

  Further, during the bus traveling, not only the processing of FIG. 9 is performed, but also local broadcasting from the local TV transmitter 110 to the TV-equipped mobile terminal 140 may be performed in parallel. In order to measure the clear level while broadcasting in this way, the method disclosed in the international application PCT / JP2008 / 053873 filed by the present applicant can be used.

  That is, using the fact that OFDM (Orthogonal Frequency-Division Multiplexing) using a plurality of carriers is adopted in the ISDB-T standard, the CPU / DSP 119 allows the TV transmission device 113 and the TV reception device 114 as follows. Can be controlled.

  It is assumed that the TV transmission device 113 currently performs local broadcasting using channel A. Also assume that channel B is the channel to be searched. The CPU / DSP 119 performs different control in the following cases (1) and (2).

(1) When channel A and channel B are different (2) When channel A and channel B are equal In the case of (1) above, the CPU / DSP 119 causes the TV transmission apparatus to perform one-segment broadcasting on channel A using weak radio waves. 113, and the TV receiver 114 is controlled to receive the radio wave of channel B. The control method of the TV receiver 114 in the case of (1) may be a known method. Further, the TV receiver 114 reports the reception intensity (specifically, the amplitude level) of the radio wave on channel B to the CPU / DSP 119. For example, the CPU / DSP 119 determines the clear level of the channel B based on the reported reception strength of the channel B and a predetermined threshold value.

  On the other hand, in the case of (2) above, if the CPU / DSP 119 performs the same control as in the case of (1) above, the radio wave itself broadcast by the TV transmission device 113 is also received by the TV reception device 114. The level cannot be measured accurately. Therefore, the CPU / DSP 119 performs the following control in order to accurately measure the clear level by distinguishing between the radio wave broadcast from the TV transmitter 113 and the radio wave from other broadcast stations and noise sources.

  That is, in the case of (2) above, the CPU / DSP 119 causes the TV transmission device 113 to perform local broadcasting by erasing a specific part of the 432 carriers used for channel A one-segment broadcasting. Control. In order to measure the clear level more accurately, it is preferable that the specific part of the carrier is located near the center of the frequency band of the channel A.

  In the case of (2) above, the CPU / DSP 119 receives the radio wave of channel B (that is, channel A) and reports the reception intensity (specifically, amplitude level) of the specific carrier. The TV receiver 114 is controlled. The reception intensity reported from the TV receiver 114 in this way is the reception intensity of the carrier that the TV transmitter 113 does not use for broadcasting, so it is not affected by the broadcast of the TV transmitter 113, and other broadcast stations or It accurately represents only the influence of interference from noise sources. Therefore, the CPU / DSP 119 can accurately determine the clear level of the channel B based on, for example, the reception intensity reported from the TV receiver 114 and a predetermined threshold value.

  As described above, when the clear level is measured in step S104 for all channels to be searched, step S105 is subsequently executed. In step S105, the CPU / DSP 119 transmits measurement data in which the point ID, the channel ID, the clear level, and the measurement time are associated to the channel setting pattern presentation device 150 via the network.

  The point ID in the measurement data is the point ID of the point determined as “arrived” in step S103. The measurement data includes a set of channel ID and clear level for each of a plurality of channels to be searched in step S104. The measurement time is acquired from the CPU clock when the process of step S104 is completed, for example.

  Although not shown in FIG. 9, the channel setting pattern presentation device 150 that has received the measurement data operates as follows. That is, the channel setting pattern presentation device 150 generates a new unique measurement number, and adds the received measurement data to the free channel measurement information table 201 in the storage device 151 as free channel measurement information together with the generated measurement number. To do.

  Subsequently, in step S106, the CPU / DSP 119 determines whether or not the clear level has been measured at all measurement points on the currently traveling route. If the clear level has already been measured corresponding to all the point IDs stored in the memory area 126 in step S101, the CPU / DSP 119 determines that “measurement has been completed at all measurement points”, and the process is step. The process proceeds to S107. Conversely, if there remains a measurement point where the clear level has not been measured, the process returns to step S103.

  In step S107, the CPU / DSP 119 stops the tuner. That is, the CPU / DSP 119 stops the reception function (that is, the function realized by the TV reception device 114) of the TV transmission / reception unit 117 of FIG. 2 by stopping the TV reception device 114 shown in FIGS. Then, the process of FIG. 9 ends.

  In step S101, when four spot IDs “P1”, “P2”, “P7”, and “P8” are acquired corresponding to the route ID “1” as described above, the processes in steps S103 to S106 are performed. A specific example of the repetition will be described as follows.

  The case where step S103 is executed for the first time is as described above. Thereafter, the clear level is measured at the point P1 in step S104, the measurement data is transmitted in step S105, and the process returns from step S106 to step S103.

  Then, step S103 is executed again. At this time, the “next measurement point” is the point P2. Therefore, the CPU / DSP 119 determines in step S103 whether the bus has arrived at the point P2.

According to the above assumption, the area is defined to have an appropriate size, and the situation regarding the empty channel is almost the same in one area. Therefore, CPU / DSP119, for example a step S103, if GPS / WLAN / BT processor within the threshold _{T d} where the straight line distance is predetermined between the current position and the point P2 of the bus obtained by 116, the "next It may be determined that the user has arrived at the point P2 that is the measurement point of "."

Subsequently, a clear level is measured at point P2 (or a nearby point whose linear distance from the point P2 is within the threshold value _Td ) at step S104, measurement data is transmitted at step S105, and the process from step S106 to step S106. Return to S103.

Similarly, when the bus arrives at the point P7 (or a nearby point whose straight line distance from the point P7 is within the threshold _Td ), steps S103 to S106 are executed again, and the process returns to step S103.

Then, when the bus arrives at the point P8 (or a nearby point whose linear distance from the point P8 is within the threshold value _Td ), steps S103 to S106 are executed again. Here, since the point P8 is the end point of the route with the route ID “1”, the process proceeds from step S106 to step S107, and the entire process of FIG. 9 is completed.

  Through the processing of FIG. 9 described above, the vacant channel measurement information is accumulated in the vacant channel measurement information table 201 of FIG. Also, as shown in FIG. 7, when a part of a plurality of routes overlaps, the result of the processing of FIG. 9 performed separately on each route is stored in the free channel measurement information table 201, respectively. It may be accumulated.

  The empty channel measurement information may further include information on the date on which the clear level measurement was performed. Then, the channel setting pattern presentation device 150 periodically checks the old entry (entry) from the empty channel measurement information table 201 (for example, the date when the measurement was performed is one month or more based on the date information). The previous entry) may be deleted.

  Moreover, the process of FIG. 9 may be performed whenever a bus | bath operates. Alternatively, for example, the process of FIG. 9 may be performed at intervals based on a rule such as “perform the process of FIG. 9 only on a bus that operates in the second week of each month”. The process of FIG. 9 may be executed at irregular intervals.

  Further, when the bus is forwarded, the local TV transmitter 110 can perform only the processing of FIG. 9 without performing local broadcasting. In this case, the clear level may be measured using a known method for detecting the reception intensity.

  By the way, the empty channel search process does not necessarily have to be performed as shown in FIG. In the modification of the first embodiment, the process of FIG. 10 may be performed instead of the process of FIG. 9, or the process of FIG. 9 and the process of FIG. 10 may be used in combination.

FIG. 10 is a flowchart of empty channel search processing in a modification of the first embodiment.
In the modified example of FIG. 10, the local TV transmitter 110 similar to that loaded on the bus is also installed at a point represented by a certain point ID. For example, the local TV transmitter 110 may be installed at a bus stop whose position is represented by a certain point ID. The local TV transmitter 110 installed at the bus stop may perform local broadcasting for passengers waiting for the bus at the bus stop. It is assumed that the location ID of the location where the local TV transmitter 110 is installed is stored in the memory area 126 in advance.

  After the local TV transmitter 110 is installed at a point represented by a certain point ID, the processing of FIG. Then, in step S201, the CPU / DSP 119 of the local TV transmitter 110 activates the tuner. Since step S201 is the same as step S102 of FIG. 9, detailed description thereof is omitted.

  In step S202, the TV receiver 114 measures the clear level for each channel to be searched according to control by the CPU / DSP 119. Step S202 is the same as step S104 in FIG.

  In step S203, the CPU / DSP 119 transmits measurement data in which the point ID, the channel ID, the clear level, and the measurement time are associated to the channel setting pattern presentation device 150 via the network. Step S203 is the same as step S105 in FIG.

  Thereafter, in step S204, the CPU / DSP 119 controls the TV receiver 114 to wait until a predetermined time elapses, and when the predetermined time elapses, the process returns to step S202. As described above, the clear level is periodically measured. The “predetermined time” may be appropriately determined based on a result of a preliminary experiment or the like according to a cycle in which the clear level varies, or may be a fixedly predetermined value.

In the local TV transmitter 110 fixed at a known position, the GPS function of the GPS / WLAN / BT processing unit 116 may be omitted.
In addition, a measurement device (not shown) that does not perform broadcasting (for example, a device in which the TV transmission device 113 is deleted from the local TV transmitter 110 in FIG. 3) can perform the processing in FIG. 10 instead of the local TV transmitter 110. . The measuring instrument may measure the clear level using a known method for detecting the reception intensity.

  FIG. 10 shows a process of periodically measuring the clear level. For example, the clear level is measured irregularly according to an irregular instruction from the channel setting pattern presentation device 150 connected via the network. It may be broken.

  Here, returning to the description of the first embodiment, the channel setting pattern presentation device 150 uses the free channel measurement information stored in the free channel measurement information table 201 in FIG. To select and present the channel setting pattern.

  FIG. 11 is a flowchart of pattern presentation processing in the first embodiment. With the pattern presentation process of FIG. 11, the channel setting pattern presentation device 150 refers to a storage device such as a RAM as a storage unit that stores the clear level in association with the spot ID and the channel ID, and a plurality of potential configurations are possible. Narrow down the channel setting pattern. Then, the channel setting pattern presentation device 150 presents one or more channel setting patterns obtained as a result of narrowing down.

  In step S301, the route ID is input to the channel setting pattern presentation device 150. For example, when the channel setting pattern presentation device 150 is realized by the computer 160 in FIG. 4, the route ID may be input via the input device 165 in FIG. 4. Alternatively, when the local TV transmitter 110 also serves as the channel setting pattern presentation device 150, the route ID may be input via the numeric keypad 124 of FIG.

  In step S302, the channel setting pattern presentation device 150 extracts the passage point ID, the reception influence time, the reception influence distance, and the point passage scheduled time based on the route ID input in step S301, and develops it as a route information table. .

  Specifically, the channel setting pattern presentation device 150 extracts the passage point ID and the scheduled passage time corresponding to the input route ID from the operation information table 203 of FIG. Moreover, the channel setting pattern presentation apparatus 150 extracts the reception influence time and the reception influence distance respectively corresponding to the plurality of passage point IDs extracted from the operation information table 203 from the influence range information table 204 of FIG. Then, the channel setting pattern presentation device 150 associates the extracted passage point ID with the reception influence time, the reception influence distance, and the point passage scheduled time, and develops them in a format as shown in FIG. To do.

FIG. 12 is a diagram illustrating an example of the developed route information table 205. FIG. 12 is an example when the route ID “1” is input in step S301 of FIG.
As shown in FIG. 7, the route ID “1” corresponds to four passage point IDs “P1”, “P2”, “P7”, and “P8”. Therefore, in step S302 of FIG. 11, these four passage point IDs and respective point passage scheduled times are extracted from the operation information table 203. Further, the reception influence time and the reception influence distance corresponding to these four passage point IDs are extracted from the influence range information table 204 of FIG.

  Therefore, in step S302 of FIG. 11, the channel setting pattern presentation device 150 receives the spot ID “P1”, the reception influence time “25 seconds”, the reception influence distance “250 m”, and “9: 00: 00: 00”. Is associated with the scheduled passage time. Further, the channel setting pattern presentation device 150 performs similar association for the other three point IDs “P2”, “P7”, and “P8”. Then, the channel setting pattern presentation device 150 expands the associated information in a format such as the route information table 205 in FIG. 12, for example, and stores it in a RAM such as the RAM 163 in FIG.

The route information table 205 in FIG. 12 implies the following bus schedule.
・ The bus departs from P1 at 9:00.
・ The bus travels 250 m in the first area represented by the point P1 over 25 seconds, and at 9:00:25, the boundary between the second area represented by the point P2 and the first area Pass through.

The bus passes through point P2 at 9:00:50, 25 seconds after passing the boundary.
・ The bus will travel in the second area for another 15 (= 40-25) seconds, and will pass the boundary between the third area and the second area represented by the point P7 at 9:01:05. . That is, the bus travels 400 m in the second area for 40 seconds from 9:00:25 to 9:01:05.

The bus passes through point P7 at 9:01:20, 15 seconds after passing the boundary.
・ The bus will travel in the third area for another 60 (= 75-15) seconds, and will pass the boundary between the fourth area and the third area represented by the point P8 at 9:02:20. . That is, for 75 seconds from 9:01:05 to 9:02:20, the bus travels 750 m in the third area.

The bus arrives at the end point P8 at 9:03:20 60 seconds after passing the boundary. That is, for 60 seconds from 9:02:20 to 9:03:20, the bus travels 600 m in the fourth area.

In FIG. 12, for convenience of explanation, 200 seconds (200 = 25 + 40 + 75 + 60), which is the total value of the reception influence times corresponding to the four spot IDs, are also displayed. FIG. 12 also displays 2000 m (2000 = 250 + 400 + 750 + 600), which is the total value of the reception influence distances corresponding to the four point IDs.

  Further, as described above, it is a coincidence that the extracted reception influence time and the reception influence distance are proportional. The reception influence time and the reception influence distance are not proportional to each other due to differences in road conditions at various points on the route.

Returning to the description of FIG. In the next step S303, the channel setting pattern presentation device 150 sets the clear level at each passing point based on the operation information table 203 in FIG. 7 and the empty channel measurement information table 201 in FIG. Expands as a channel information table 206a. The free channel information table 206a is developed on a RAM such as the RAM 163 in FIG.

That is, since the free channel information tables 206a and 206b are created based on the free channel measurement information table 201 of FIG. 5, it can be said that they are indirectly created by the processing of FIG. 9 or FIG. For example, in step S105 of FIG. 9, the channel setting pattern presentation device 150 associates the measured clear level with the spot ID of the measurement target point and the channel ID of the measurement target channel in the free channel information tables 206a and 206b . It can be said that it is preparation for writing.

  FIG. 13A is a diagram showing a first example of the developed empty channel information table. In FIG. 13A, the route information table 205 of FIG. 12 is also displayed for convenience of reference.

  Hereinafter, for the convenience of explanation, in areas where there are areas represented by point P1, point P2, point P7, and point P8, it is determined in advance that channels other than channels 13 to 16 are not free channels among the 50 physical channels. It shall be. In other words, it is assumed that the search target is the channels 13 to 16 at any of the points P1, P2, P7, and P8. Note that, for example, a channel used by a broadcasting station is an example of a channel that has been previously determined not to be a free channel.

  In the free channel information table 206a in FIG. 13A, each row corresponds to each channel to be searched, and each column corresponds to each point ID. Each cell in the free channel information table 206a represents a clear level. For example, in FIG. 13A, a clear level of “3” corresponds to a set of “13” and “P1”.

  In step S303 in FIG. 11, the channel setting pattern presentation device 150 performs the following processing in order to obtain such an empty channel information table 206a and store it in the memory area 126.

  The four passing point IDs “P1”, “P2”, “P7”, and “P8” corresponding to the route ID input in step S301 and the respective scheduled passage times are already displayed in step S302 in FIG. Extracted from the table 203. The channel setting pattern presentation device 150 searches the empty channel measurement information table 201 of FIG. 5 using the extracted passing point ID and the estimated passing time as search keys.

For example, in FIG. 7, the passage point ID “P1” corresponds to the point passage scheduled time “9: 00: 00: 00”. Therefore, the channel setting pattern presentation device 150 searches the empty channel measurement information table 201 for an entry having the point ID “P1” and the measurement time close to “9:00:00”. If the processing of FIG. 9 has already been appropriately performed for each flight of each route so that a sufficient amount of free channel measurement information is accumulated in the free channel measurement information table 201 of FIG. One entry is obtained. Incidentally, if the absolute value of the difference between the two is the threshold T _n less than or equal to a predetermined, two times are close to each other, shall be defined as.

For example, in FIG. 5, an entry whose measurement number is “1” has a point ID “P1” and a measurement time “9:00”. Therefore, as a result of the search corresponding to the set of the passing point ID “P1” and the scheduled passing time of “9: 00: 00: 00”, at least an entry whose measurement number is “1” is obtained. Value and the threshold value T _n, depending on the content of the idle channel measurement information stored in the idle channel measurement information table 201, sometimes still another entry obtained as a result of the search.

In addition, in FIG. 5, the entry whose measurement number is “2” has the point ID “P2” and the measurement time “9:10:00”. Therefore, if the value of, for example, the threshold T _n is 15 minutes, as a passing point ID and the result of the search corresponding to the combination of spot passage estimated time of "9:00:50" as "P2", the measurement No "2 Is obtained. Conversely, if the value of, for example, the threshold _{T n} is 5 minutes, it is determined that "9:00:50" and two times of "9:10:00" is "not close", a result of the search, An entry whose measurement number is “2” cannot be obtained.

  When only one entry is obtained as a result of the search of the free channel measurement information table 201, the channel setting pattern presentation device 150 reads a set of channel ID and clear level from the obtained entry. Then, the channel setting pattern presentation device 150 writes the read clear level value in the free channel information table 206a of FIG. 13A.

  For example, it is assumed that only the entry whose measurement number is “1” in FIG. This entry includes a pair of a channel ID “13” and a clear level “3”. Therefore, the channel setting pattern presentation device 150 writes the clear level “3” in the cell where the column “P1” and the row “13” intersect in the free channel information table 206a.

  When a plurality of entries are obtained as a result of the search, the channel setting pattern presentation device 150 reads, for each channel ID, the clear level corresponding to the channel ID from each entry obtained as a result of the search. Then, the channel setting pattern presentation device 150 determines the clear level to be written in the empty channel information table 206a based on the read multiple clear levels.

  For example, it is assumed that three entries are obtained as a result of the search corresponding to the set of the point ID “P2” and the point passing scheduled time “9:00:50”. Then, the channel setting pattern presentation device 150 reads the clear level corresponding to the channel ID “13” in each of the three entries.

  For example, assume that the clear levels read from the three entries are “1”, “2”, and “2”, respectively. Then, the channel setting pattern presentation device 150 performs a predetermined process based on the three values “1”, “2”, and “2”, and sets a clear level to be written in the empty channel information table 206a, for example, “ 2 ”.

  The “predetermined process” may be, for example, a process of obtaining a mode value or other statistical processes such as obtaining a median value, a maximum value, a minimum value, or an average value. Then, the channel setting pattern presentation device 150 writes the determined value (“2” in the above example) in the cell where the column “P2” and the row “13” intersect in the empty channel information table 206a.

  As described above, the channel setting pattern presentation device 150 searches the free channel measurement information table 201 for each point ID, and each row of the free channel information table 206a is based on one or more entries obtained as a result of the search. Write a value to the cell. As a result, an empty channel information table 206a as shown in FIG. 13A, for example, is generated and expanded in the memory area 126 or the like.

  FIG. 13B is a diagram showing a second example of the developed empty channel information table. The empty channel information table 206b in FIG. 13B is the same as the empty channel information table 206a in FIG. In addition, the route information table 205 is also displayed in FIG. 13B for convenience of reference.

  Returning to the description of FIG. 11, in the next step S304, the channel setting pattern presentation device 150 determines whether there are continuous free channels over all points on the route specified by the route ID.

  For example, when the route ID “1” is input in step S301, as shown in FIG. 7, “all points” are four points, that is, point P1, point P2, point P7, and point P8. In the first embodiment, the clear level is represented by three levels of discrete values. “2” represents “normal” and “3” represents “good”. Therefore, a channel that can obtain a clear level of “normal” or higher is regarded as an empty channel. Further, it is assumed that the free channel information table 206a is expanded as shown in FIG. 13A as a result of step S303.

  Then, in step S304, the channel setting pattern presentation device 150 determines the channel that remains an empty channel over the four columns “P1”, “P2”, “P7”, and “P8” in the empty channel information table 206a of FIG. 13A. Judgment of existence.

  In the example of FIG. 13A, the row where the clear level of “2” or higher is written in all four columns is only the row of the channel ID “14”. Therefore, the channel setting pattern presentation device 150 determines that the channel 14 is an empty channel that is continuous over all points.

  Alternatively, when a route ID “1” is input in step S301, depending on the contents of the empty channel measurement information table 201 in FIG. 5, the empty channel information table 206b is expanded as shown in FIG. 13B as a result of step S303. It may be. Then, in step S304, channel setting pattern presentation apparatus 150 determines that there are no free channels that are continuous over all points. This is because, in FIG. 13B, there is no row in which the clear level of “2” or higher continues over four columns.

  As described above, in step S304, whether or not a plurality of (four in the above example) channel setting patterns that associate the N channel IDs with the same channel ID continues with a clear level of “2” or higher over all points. It is evaluated from the viewpoint. If there are continuous free channels over all points, the process proceeds to step S305, and if there are no continuous free channels over all points, the process proceeds to step S309.

  In step S305, the channel setting pattern presentation device 150 determines whether there are a plurality of channels determined in step S304 as being free channels that are continuous over all points.

  Here, it is assumed that a certain channel X is an empty channel continuous over all points. Then, the channel setting pattern PAT that associates the channel X with all points on the designated route can continue local broadcasting with good reception quality without changing the channel from the start point to the end point of the route. This is a channel setting pattern that is expected to be possible. Therefore, the channel setting pattern PAT is suitable for performing local broadcasting without imposing a burden on passengers on the bus.

  That is, in step S305, the channel setting pattern presentation device 150 determines whether there are a plurality of channel setting patterns expected to be able to continue local broadcasting while maintaining good reception quality without changing the channel. Judgment. If it is determined that there is only one channel setting pattern as described above, the process proceeds to step S306. If there are a plurality of channel setting patterns as described above, the process proceeds to step S307.

  In step S306, the channel setting pattern presentation device 150 selects the one channel setting pattern found in step S305 as a channel setting pattern to be presented. Then, the process proceeds to step S308.

  In step S307, the channel setting pattern presentation device 150 calculates a score for each of the plurality of channel setting patterns found in step S305. Then, the channel setting pattern presentation device 150 selects the channel setting pattern with the highest score as the channel setting pattern to be presented, and the process proceeds to step S308.

  The score calculated in step S307 is an evaluation value based on the clear level, and a specific calculation formula is arbitrary depending on the embodiment. In the first embodiment, as the score of the channel setting pattern, the sum of the clear levels corresponding to the set of the spot ID and the channel ID associated with the channel setting pattern is used. That is, it is as follows if formally defined.

The route R is represented by an N-tuple including N point IDs as in Expression (1). In equation (1), each p _j (1 ≦ j ≦ N) is a point ID, and the N point IDs are ordered in the N tuple according to the order on the route.

R = (p ₁ , p ₂ ,..., P _N ) (1)
The channel setting pattern PAT related to the path R can be represented by an N tuple including N channel IDs as in Expression (2). The j-th channel ID · c _{i (j} ) in equation (2) is associated with the j-th point ID · p _j in equation (1) by being the j-th element of the N tuple. That is, the channel setting pattern PAT is a combination pattern that associates channel IDs with N point IDs.

PAT = (c _{i (1)} , c _{i (2)} ,..., C _{i (N)} ) (2)
Hereinafter, in the empty channel information table developed in step S303 (for example, the empty channel information table 206b in FIG. 13B), the clear level corresponding to the pair of the channel ID · c _{i (j)} and the point ID · p _j is set to “a _{i (j), j} ". Then, the score of the channel setting pattern PAT in the first embodiment is defined by Expression (3).

例えば、「１」という経路ＩＤで識別される経路（以下「Ｒ１」と表記する）は、図７と式（１）より、（Ｐ１，Ｐ２，Ｐ７，Ｐ８）という４タプルで表される。また、図１３Ａの空きチャネル情報テーブル２０６ａにおいて全地点にわたり連続する空きチャネルであるチャネル１４を各地点ＩＤに対応付けるチャネル設定パターン（以下「ＰＡＴａ」と表記する）は、式（２）より（１４，１４，１４，１４）という４タプルで表される。また、図１３Ａと式（３）より、チャネル設定パターンＰＡＴａのスコアは、具体的には空きチャネル情報テーブル２０６ａにおけるチャネルＩＤ「１４」の行の４つの値の総和であるから、式（４）のように計算される。

For example, a route identified by a route ID “1” (hereinafter referred to as “R1”) is represented by a 4-tuple (P1, P2, P7, P8) from FIG. 7 and Expression (1). In addition, a channel setting pattern (hereinafter referred to as “PATa”) that associates the channel 14 that is an empty channel continuous over all points in the empty channel information table 206a of FIG. 13A with each point ID is expressed by (14, 14, 14, 14). Further, from FIG. 13A and Expression (3), the score of the channel setting pattern PATa is specifically the sum of the four values in the row of the channel ID “14” in the empty channel information table 206a. It is calculated as follows.

s (PATa) = 2 + 2 + 3 + 3 = 10 (4)
Of course, the definition of the score is arbitrary depending on the embodiment. For example, since the clear level of “1” corresponds to poor reception quality, Equation (5) is substituted for Equation (3) so that the clear level of a _{i (j), j} = 1 does not affect the score. It may be used.

以上説明したように、ステップＳ３０７では、ステップＳ３０４で見つかった複数の空きチャネルに対応する複数のチャネル設定パターンのそれぞれについて、チャネル設定パターン提示装置１５０がクリアレベルに基づくスコアを算出する。そして、チャネル設定パターン提示装置１５０は、スコアが最高のチャネル設定パターンを、提示対象として選択する。

As described above, in step S307, the channel setting pattern presentation device 150 calculates a score based on the clear level for each of the plurality of channel setting patterns corresponding to the plurality of empty channels found in step S304. And the channel setting pattern presentation apparatus 150 selects the channel setting pattern with the highest score as a presentation target.

  When there are two or more channel setting patterns with the highest score, the channel setting pattern presentation device 150 may select only one of them based on criteria other than the score, or two or more channels with the highest score. All setting patterns may be selected. In addition, depending on the embodiment, the channel setting pattern presentation device 150 may select all the plurality of channel setting patterns corresponding to the plurality of empty channels found in step S304 without calculating the score in step S307. . When channel setting pattern presentation device 150 selects one or more channel setting patterns, the process proceeds to step S308.

  In step S <b> 308, the channel setting pattern presentation device 150 transfers information on the channel setting pattern selected as the presentation target to the local TV transmitter 110. Transfer to the local TV transmitter 110 is an example of a specific method for presenting a channel setting pattern.

  For example, when the channel setting pattern presentation device 150 is realized by the computer 160 of FIG. 4, the CPU 161 transmits information on the channel setting pattern selected as a presentation target to the local TV transmitter via the communication interface 164 and the network 171. 110. That is, the communication interface 164 as a data transmission device may be used for presenting a channel setting pattern.

  When the channel setting pattern presentation device 150 is realized by the computer 160 in FIG. 4, the CPU 161 further outputs the channel setting pattern to the output device 166 so that the selected channel setting pattern is visually or audibly heard. May be presented. Specifically, the output device 166 is a display, a printer, a speaker, or the like.

  Alternatively, as described above, the local TV transmitter 110 may also serve as the channel setting pattern presentation device 150. In that case, the CPU / DSP 119 of the local TV transmitter 110 shown in FIG. 2 may visually or audibly present the selected channel setting pattern on the display 125 or the speaker 122.

When the channel setting pattern is presented in step S308, the processing in FIG. 11 ends.
The presented channel setting pattern may be automatically set in the local TV transmitter 110. Alternatively, the channel setting pattern presented by the channel setting pattern presentation device 150 may be output to the display 125 or the speaker 122 of the local TV transmitter 110. Then, an operator such as a bus driver or a conductor confirms the output channel setting pattern, and the channel setting presented by the channel setting pattern presentation device 150 via an input device such as the numeric keypad 124 of FIG. You may perform input which approves a pattern. Then, the CPU / DSP 119 may set the approved channel setting pattern as a channel setting pattern for controlling the TV transmission device 113.

  The local TV transmitter 110 can perform local broadcasting by the TV transmitter 113 of FIGS. 1 and 3 according to the channel setting pattern set as described above. According to the set channel setting pattern, for example, the conductor may notify the passenger verbally about the channel switching. Therefore, according to the first embodiment, it is possible to provide a content distribution service based on local broadcasting in a moving bus without placing a heavy burden on the passengers of the bus.

  Here, the description returns to the branch in step S304. If an empty channel continuous over all points is not found in step S304, the process proceeds to step S309. The processing after step S309 includes processing for generating all combinable channel setting patterns, evaluating each of the generated channel setting patterns based on the clear level, and selecting a channel setting pattern with high evaluation.

  Specifically, in step S309, the channel setting pattern presentation device 150 creates a channel setting pattern table based on the empty channel information table developed in step S303. Hereinafter, the case where the empty channel information table 206b of FIG. 13B is obtained in step S303 will be described as an example.

  FIG. 14 is a diagram illustrating an example of a channel setting pattern table. In the channel setting pattern table 207 of FIG. 14, each row corresponds to one channel setting pattern. The channel setting pattern table 207 is created on a RAM such as the RAM 163 in FIG.

  Here, the empty channel information table 206b in FIG. 13B is a table related to the route R1 = (P1, P2, P7, P8). Therefore, the channel setting pattern table 207 of FIG. 14 generated based on the free channel information table 206b of FIG. 13B is also a table related to the route R1.

  Similarly to FIG. 13A, FIG. 13B shows an example of “the search target is four channels 13 to 16 at any of the points P1, P2, P7, and P8”. Therefore, if the number of point IDs on the route R1 is N and the number of channels to be searched is M, N = 4 and M = 4. Therefore, the total number of channel setting patterns that can be combined is expressed as shown in Equation (6).

t = M ^N = 4 ⁴ = 256 (6)
More generally, the number of search target channels is not always the same at N points represented by N point IDs in the route R of the formula (1). Therefore, if the number of channels to be searched at the j-th point represented by the point ID · p _j (1 ≦ j ≦ N) is m _j , the total number of channel setting patterns that can be combined is as shown in Equation (7). expressed. Expression (6) is an expression showing a case where m _j = M for all j satisfying 1 ≦ j ≦ N in Expression (7).

式（６）に示されるように、図１３Ｂの空きチャネル情報テーブル２０６ｂに基づいて図１１のステップＳ３０９では、２５６個のチャネル設定パターンがチャネル設定パターン提示装置１５０により生成され、チャネル設定パターンテーブル２０７に記憶される。図１４では紙面の都合上、一部の行を省略している。

As shown in Expression (6), based on the empty channel information table 206b in FIG. 13B, in step S309 in FIG. 11, 256 channel setting patterns are generated by the channel setting pattern presentation device 150, and the channel setting pattern table 207 is displayed. Is remembered. In FIG. 14, some lines are omitted for the sake of space.

  Further, as shown in FIG. 14, the channel setting pattern table 207 includes columns of channel IDs and clear levels respectively corresponding to the four point IDs that define the route R1. Further, the channel setting pattern table 207 includes a score column calculated in step S310 described later, and a channel change count, the same channel continuous time, and the same channel total time calculated in step S311 described later.

  In step S309 in FIG. 11, the channel setting pattern presentation device 150 generates a channel setting pattern table 207 by writing values in the four sets of channel IDs and clear levels for each of the 256 channel setting patterns.

For example, the channel setting pattern PAT01 shown in FIG. 14 can be expressed as Equation (8) by the notation of Equation (2).
PAT01 = (13, 13, 14, 13) (8)
Referring to FIG. 13B, the clear level corresponding to the set of the first point ID “P1” on the route R1 and the channel ID “13” which is the first element of the 4-tuple of Expression (8) is “3”. It is. The clear level corresponding to the set of the second point ID “P2” on the route R1 and the channel ID “13” that is the second element of the 4-tuple of Expression (8) is “3”. The clear level corresponding to the set of the third point ID “P7” on the route R1 and the channel ID “14” that is the third element of the 4-tuple of Expression (8) is “3”. Further, the clear level corresponding to the set of the fourth point ID “P8” on the route R1 and the channel ID “ 13 ” that is the fourth element of the 4-tuple of Expression (8) is “3”.

  The channel setting pattern presentation device 150 generates a channel setting pattern PAT01, and values “13”, “13”, “14”, and “13” are respectively displayed in the cells of the four channel ID columns in the row of the channel setting pattern PAT01. Write. Further, the channel setting pattern presentation device 150 writes the four values read from the empty channel information table 206b (all values “3”) into the cells in the four clear level columns of the row of the channel setting pattern PAT01.

  Similarly for the other 255 channel setting patterns, the channel setting pattern presenting apparatus 150 refers to the empty channel information table 206b to set values in the first to eighth columns of the channel setting pattern table 207. Write. The ninth column to the twelfth column will be described later.

  Returning to the description of FIG. Subsequent to step S309, in step S310, the channel setting pattern presentation device 150 calculates a score based on the clear level for each channel setting pattern generated in step S309. Then, the channel setting pattern presentation device 150 writes the calculated score in the ninth column (that is, the “score” column) of the channel setting pattern table 207 of FIG.

  In the first embodiment, in step S310, the score defined by equation (3) is calculated as in step S307. For example, as described above, in the channel setting pattern PAT01, the four clear levels corresponding to each set of point ID and channel ID are all “3”. Therefore, the score of the channel setting pattern PAT01 is calculated by the following equation (9).

s (PAT01) = 3 + 3 + 3 + 3 = 12 (9)
In other words, the channel setting pattern presentation device 150 calculates the score by the equation (9) using the four clear level values written in the row of the channel setting pattern PAT01 of the channel setting pattern table 207 in step S309, and calculates “score In the column. Similarly, the channel setting pattern presentation apparatus 150 calculates a score based on Expression (3) for the other 255 channel setting patterns and writes it in the “score” column.

Subsequently, in step S <b> 311, the channel setting pattern presentation device 150 calculates the following (a) to (c) for each channel setting pattern generated in step S <b> 309, and the cells in the tenth to twelfth columns of the channel setting pattern table 207. Write the calculation results in each. In the following, although attention is paid to “continuous” and “adjacent” of channel IDs, continuous in a broad sense that non-continuous parts corresponding to a predetermined condition are regarded as continuous and continuous with no other channel ID interposed therebetween. Which means is clear from the context of each part. Therefore, in the following, continuity in the broad sense is also simply referred to as continuity.

(A) Channel change count (b) Same channel continuous time (c) Same channel total time The channel setting pattern presentation device 150 counts the number of channel changes in (a). Attention is paid to a pair of two adjacent channel IDs under the condition that the clear level corresponding to the ID is equal to or greater than a threshold value. Then, the channel setting pattern presentation device 150 counts the number of locations where the two channel IDs of interest are different. The counted result is the number of channel changes. In the first embodiment, “2” is used as the threshold value.

  For example, regarding PAT01 = (13, 13, 14, 13), as shown in FIG. 14, the clear levels corresponding to the four channel IDs are all “2” or more. Therefore, there are the following three sets of two channel IDs adjacent to each other under the condition that “the clear level corresponding to the channel ID is equal to or greater than the threshold”.

(1) The first channelization Le ID "13" and the second set of channel ID "13" (2) The second channelization Le set of ID "13" and the third channel ID "14" (3 ) of the pairs the three sets of the third channelization Le ID "14" and the fourth channel ID "13", the set of (2) and (3), two channel ID is different. Accordingly, the channel setting pattern PAT01 has a channel change count of “2”, and the channel setting pattern presentation device 150 writes “2” in the “channel change count ” column in the row of the channel setting pattern PAT01.

  FIG. 14 also shows a channel setting pattern of PAT09 = (13, 13, 15, 13). Regarding the channel setting pattern PAT09, as shown in FIG. 14, the clear levels corresponding to the four channel IDs are “3”, “3”, “1” and “3”, respectively. Therefore, the first, second and fourth channel IDs in the four tuples (13, 13, 15, 13) apply to the condition that “the clear level corresponding to the channel ID is equal to or greater than the threshold”. Therefore, the two sets of adjacent channel IDs under the above conditions are the following two sets.

(1) Set of first channel ID “13” and second channel ID “13” (2) Set of second channel ID “13” and fourth channel ID “13” Any of the above two sets Also, the two channel IDs are equal. Therefore, the channel change count of the channel setting pattern PAT07 is “0”.

  As described above, the channel setting pattern presentation device 150 counts the number of times the channel is changed after setting the condition that “the clear level corresponding to the channel ID is equal to or greater than the threshold” as follows.

  Here, for convenience of explanation, a tuple in which values written in the four “clear level” columns of the channel setting pattern table 207 are arranged according to the order of the corresponding points on the route is referred to as a “clear level tuple”. It is represented by 4 tuples (generally N tuples).

  Assuming that the channel setting pattern PAT09 is adopted, in the first and second areas (that is, the areas represented by the points P1 and P2 respectively), the TV transmitter 113 of the local TV transmitter 110 on the channel 13 Broadcast locally. Since the clear level tuple of the channel setting pattern PAT09 is (3, 3, 1, 3), good reception quality is predicted in the first and second areas.

  On the other hand, according to the channel setting pattern PAT09, in the third area (that is, the area represented by the point P7), the TV transmission device 113 performs local broadcasting on the channel 15, but the reception quality is predicted to be poor. This is because the third element of the clear level tuple is “1”.

  Therefore, in the first embodiment, it is assumed that the local TV transmitter 110 suspends the local broadcast in an area where only a clear level less than “2” that is the threshold is obtained based on the adopted channel setting pattern. . This is because even if broadcasting, if the reception quality is poor, the meaning of broadcasting is weak.

  Then, when the passenger enters the third area, there is no point in changing the reception channel from the currently set reception channel (that is, channel 13) to channel 15 for the passenger. Therefore, as described above, when the channel setting pattern presentation device 150 counts the number of channel changes, the condition that “the clear level corresponding to the channel ID is equal to or greater than the threshold” is set.

In some embodiments, the local TV transmitter 110 can perform local broadcasting even if the clear level is “1” according to the adopted channel setting pattern. In that case, the definition of the number of channel changes may be different from the above. For example, the channel setting pattern presentation apparatus 150 may count the number of locations where different channel IDs are adjacent to each other without providing the above-described conditions in the N tuple of channel IDs representing the channel setting pattern.

  Next, the same channel continuous time (b) calculated in step S311 will be described. The channel setting pattern presentation device 150 calculates the length of the same channel ID that satisfies the same condition as above, “the clear level corresponding to the channel ID is equal to or greater than the threshold”, using the reception influence time. As will be described below, one or more calculation results are obtained for each channel setting pattern, and the maximum value of the obtained calculation results is the same channel continuous time.

  As shown in FIG. 14, for example, the clear level tuple of the channel setting pattern PAT07 = (13, 13, 13, 13) is (3, 3, 1, 3). Therefore, there are the following two sections in which the same channel ID is continued under the condition that the clear level is “2” or more.

(1) Sections corresponding to the first to second channel IDs (that is, sections corresponding to the first and second areas represented by the points P1 and P2, respectively)
(2) Section corresponding to the fourth channel ID (that is, section corresponding to the fourth area represented by the point P8)
The channel setting pattern presentation device 150 reads the reception influence time corresponding to each point from the route information table 205 of FIG. 12 that has been expanded in step S302 of FIG. And the channel setting pattern presentation apparatus 150 performs each addition as needed, and acquires each length of (1) and (2).

  As a result, 65 (= 25 + 40) seconds is obtained as the length of (1), and 60 seconds is obtained as the length of (2). Therefore, the maximum 65 seconds of these two results is obtained as the same channel continuous time of the channel setting pattern PAT07, and is written in the 11th column of the channel setting pattern table 207 of FIG. .

  Next, the total time of the same channel (c) calculated in step S311 will be further described. The channel setting pattern presentation device 150 aggregates the corresponding reception influence times for each channel ID under the same condition as described above that “the clear level corresponding to the channel ID is equal to or greater than the threshold”. The maximum value of the total results is the same channel total time.

  As shown in FIG. 14, for example, the clear level tuple of the channel setting pattern PAT02 = (13, 13, 14, 16) is (3, 3, 3, 3). Therefore, when the points on the route R1 are classified for each channel ID under the condition that the clear level is “2” or more, the points are classified into the following three.

(1) Point P1 and point P2 corresponding to channel 13
(2) Point P7 corresponding to channel 14
(3) Point P8 corresponding to channel 16
The channel setting pattern presentation device 150 reads the reception influence time corresponding to each point from the route information table 205 of FIG. 12 that has been expanded in step S302 of FIG. And the channel setting pattern presentation apparatus 150 performs the addition as needed, and obtains the sum of the reception influence time corresponding to each of (1)-(3).

  As a result, 65 (= 25 + 40) seconds are obtained corresponding to (1), 75 seconds are obtained corresponding to (2), and 60 seconds are obtained corresponding to (3). Therefore, the maximum of 75 seconds among these three results is obtained as the same channel total time of the channel setting pattern PAT02, and is written in the 12th column of the channel setting pattern table 207 by the channel setting pattern presentation device 150.

  As described above, in step S311, the channel setting pattern presentation device 150 calculates (a) to (c) for all of the t (= 256) channel setting patterns and writes them in the channel setting pattern table 207. In some embodiments, the same channel continuous distance may be calculated instead of (b) using the reception affected distance instead of the reception affected time, and the same channel total distance may be calculated instead of (c). It may be calculated.

  Subsequently, in step S312, the channel setting pattern presentation device 150 determines a reference that is given priority as a reference for selecting a channel setting pattern. The priority reference may be set in the channel setting pattern presentation device 150 in advance, or may be designated via an input device (such as the input device 165 in FIG. 4) in step S312. The channel setting pattern presentation device 150 can determine a priority reference by reading preset content or input content. In the first embodiment, there are (a) the number of times of channel change, (b) the same channel continuous time, and (c) the same channel total time as options for the priority reference.

  When the priority criterion is the number of channel changes, the process proceeds to step S313. When the priority reference is the same channel continuous time, the process proceeds to step S314. When the priority reference is the same channel total time, the process proceeds to step S315.

  In step S313, the channel setting pattern presentation device 150 extracts the channel setting pattern having the highest score from t (= 256) channel setting patterns included in the channel setting pattern table 207. Further, the channel setting pattern presentation device 150 extracts the channel setting pattern with the highest score from the channel setting patterns with the smallest number of channel changes and selects it as a presentation target. Then, the process proceeds to step S308 described above.

  In step S314, channel setting pattern presentation apparatus 150 extracts a channel setting pattern having the highest score from t channel setting patterns included in channel setting pattern table 207. Furthermore, the channel setting pattern presentation device 150 extracts the channel setting pattern with the highest score from the channel having the longest same channel continuous time and selects it as a presentation target. Then, the process proceeds to step S308.

  In step S315, the channel setting pattern presentation device 150 extracts the channel setting pattern having the highest score from the t channel setting patterns included in the channel setting pattern table 207. Furthermore, the channel setting pattern presentation device 150 extracts the channel setting pattern with the highest score from the longest same channel total time and selects it as a presentation target. Then, the process proceeds to step S308.

  It should be noted that the criteria that can be selected in step S312 may be arbitrary depending on the embodiment, and can be appropriately determined according to the preference of the business operator or passenger who performs the content distribution service by the local TV transmitter 110. For example, the channel setting pattern presentation device 150 may select the channel setting pattern to be presented based on a combination of two or more of the channel change count, the same channel continuous time, and the same channel total time.

  Further, instead of selecting all the references (a) to (c) in step S311, and then selecting the reference in step S312, as described above, the reference is selected first, and only the calculation related to the selected reference is performed. May be performed by the channel setting pattern presentation device 150.

Further, the extraction in steps S313 to S315 may vary depending on the embodiment.
For example, in steps S313 to S315, the channel setting pattern presentation device 150 may extract a channel setting pattern having a score equal to or higher than the threshold value T _s instead of first extracting the channel setting pattern having the highest score as described above. Good. The threshold value T _s may be determined in advance according to the length of the route selected in step S301 (that is, the number N of point IDs that define the route). For example, clear level representing the "normal" because _"2", may be the T s = _2N, may be determined as such as T s = 2.5N.

Alternatively, in steps S313 to S315, channel setting pattern presentation apparatus 150 may first extract a channel setting pattern whose score falls within the upper T _u % based on the distribution of scores in the generated t channel setting patterns. . The value of the T _u may be be predetermined, may be designated by an input such as from the operator.

Further, for example, in step S313, the channel setting pattern presentation device 150 may extract a channel setting pattern that falls in T _f % from the channel setting pattern with the highest score from the one with the smallest number of channel changes. The value of _Tf may be determined in advance or may be designated by input from an operator or the like.

  Similarly, in steps S314 and S315, it is not always necessary to perform extraction limited to only the channel setting pattern having the longest same channel continuous time or the same total channel time. The channel setting pattern presentation device 150 may extract a plurality of channel setting patterns having relatively long identical channel continuous time or identical channel total time.

  As described above, steps S312 to S315 can be variously modified. However, each channel setting pattern is evaluated based on a clear level corresponding to each set of spot ID and channel ID associated with each other in each generated channel setting pattern and a threshold value “2” indicating an allowable level. Both are common.

That is, the point that the channel setting pattern is evaluated by an index representing the distribution of the clear level equal to or higher than the threshold value “2” in the clear level tuple is common to the various modifications exemplified above. The distribution of the clear level can be represented by, for example, the number of channel changes, the same channel continuous time, the same channel total time, the same channel continuous distance, or the same channel total distance. Note that the number of channel changes, the same channel continuous time, and the same channel continuous distance are the degree to which the same channel ID corresponding to the clear level of “2” or higher in the N tuple of the equation (2) indicating the channel setting pattern is continuous (ie, An index indicating the distribution from the viewpoint of the degree of continuity in the sense of continuity in a broad sense that the non-continuous part corresponding to the predetermined condition is also considered to be continuous, or the degree of continuity without interposing another channel ID) It is.

Subsequently, a display example of the channel setting pattern presented by the processing of FIG. 11 will be described.
For example, the channel setting pattern presentation device 150 not only transfers the selected one or more channel setting patterns to the local TV transmitter 110 in step S308 of FIG. 11, but also displays a display (for example, the output device of FIG. 4). 166). Alternatively, the local TV transmitter 110 that has received the channel setting pattern information from the channel setting pattern presentation device 150 may display the channel setting pattern on the display 125 of FIG. When the local TV transmitter 110 also serves as the channel setting pattern presentation device 150, the display 125 of FIG. 2 may display one or more selected channel setting patterns in step S308 of FIG.

FIG. 15A is a diagram illustrating a first display example. FIG. 15A is a display example when the free channel information table 206a of FIG. 13A is obtained in step S303 of FIG.
As shown in FIG. 13A, there is only one free channel that is continuous over all points in the free channel information table 206a. Therefore, a channel setting pattern in which the channel ID “14” is associated with each of the spot IDs “P1”, “P2”, “P7”, and “P8” is selected in step S306 in FIG. The selected channel setting pattern is displayed as a display example 208a in FIG. 15A, for example. That is, four clear levels “2”, “2”, “3”, and “3” respectively associated with the four spot IDs are displayed next to the channel ID “14”. That is, the display example 208a is an excerpt of the line of the channel ID “14” in the empty channel information table 206a of FIG. 13A.

  FIG. 15B is a diagram illustrating a second display example. FIG. 15B shows a case where the free channel information table 206b of FIG. 13B is obtained in step S303 of FIG. 11, the channel setting pattern table 207 of FIG. 14 is obtained in steps S309 to S311, and the number of channel changes is selected in step S312. Is a display example.

  In this case, the route R1 = (P1, P2, P7, P8) selected in step S301 includes four point IDs, and the maximum value of the clear level is 3, so the score is theoretically at most 12 (= 3 × 4). The score is actually 12 in the following six channel setting patterns from FIG. 13B.

PAT01 = (13, 13, 14, 13)
PAT02 = (13, 13, 14, 16)
PAT03 = (13, 14, 14, 13)
PAT04 = (13, 14, 14, 16)
PAT05 = (13, 16, 14, 13)
PAT06 = (13, 16, 14, 16)
Further, in all channel setting patterns PAT01 to PAT04, the number of channel changes is two. On the other hand, the channel setting patterns PAT05 to PAT06 all have three channel change times. Accordingly, channel setting patterns PAT01 to PAT04 are selected in step S313.

  The display example 208b in FIG. 15B is a table format, and each row corresponds to one channel setting pattern. Corresponding to the selected channel setting patterns PAT01 to PAT04, four lines are displayed in the display example 208b.

The pattern ID for identifying the channel setting pattern is displayed in the first column of the display example 208b, and the four spot IDs “P1,” “P2,” “P7,” and “P8” are displayed in the second to fifth columns. The channel ID associated with each is displayed . On the right side outside the table frame, the number of channel changes in the channel setting pattern represented by each row is displayed as “2 times”.

  FIG. 15C is a diagram illustrating a third display example. 15C, the free channel information table 206b of FIG. 13B is obtained in step S303 of FIG. 11, the channel setting pattern table 207 of FIG. 14 is obtained in steps S309 to S311, and the same channel continuous time is selected in step S312. This is a display example.

  As described with reference to FIG. 15B, the channel setting patterns PAT01 to PAT06 have the highest scores among the 256 channel setting patterns in FIG. Further, from the definition of the same channel continuous time, the same channel continuous time of the channel setting patterns PAT01, PAT02, PAT05, and PAT06 is 75 seconds. On the other hand, the same channel continuous time of the channel setting patterns PAT03 and PAT04 is 115 (= 40 + 75) seconds.

  Therefore, in step S314 of FIG. 11, two channel setting patterns PAT03 and PAT04 having the longest continuous channel time are selected from the six channel setting patterns having the highest score.

The display example 208c in FIG. 15C is also in a table format, and each row corresponds to one channel setting pattern. In the display example 208c, two lines corresponding to the selected channel setting patterns PAT03 and PAT04 are displayed. The pattern ID for identifying the channel setting pattern is displayed in the first column of the display example 208c, and the four spot IDs “P1,” “P2,” “P7,” and “P8” are displayed in the second to fifth columns. The channel ID associated with each is displayed . The same channel continuous time in the channel setting pattern represented by each row is displayed on the right side outside the table frame.

  FIG. 15D is a diagram illustrating a fourth display example. 15D, the free channel information table 206b of FIG. 13B is obtained in step S303 of FIG. 11, the channel setting pattern table 207 of FIG. 14 is obtained in steps S309 to S311, and the same total channel time is selected in step S312. This is a display example. FIG. 15D is also a display example when the subsequent processing of step S315 is different from the above example.

  Specifically, the channel setting pattern presentation device 150 may perform the following process instead of the process of step S315. That is, channel setting pattern presentation apparatus 150 may extract a channel setting pattern having a score equal to or higher than a threshold value (for example, 2N = 8) from 256 channel setting patterns. Then, the channel setting pattern presentation device 150 may select an extracted channel setting pattern that has the same total channel time as a threshold (for example, 110 seconds) or more as a presentation target. Here, assuming that “*” represents don't care, the following two types of channel setting patterns are selected.

A channel setting pattern in which the total time for the same channel is 125 (= 25 + 40 + 60) seconds (13, 13, *, 13) The total time for the same channel is 115 (= 40 + 75) seconds (*, 14, 14, *) The channel setting pattern 208d in FIG. 15D also has a table format, and each row corresponds to one channel setting pattern. In the display example 208d, rows are arranged in the sorted order using the same channel total time as a sort key. For the sake of space, only one of the 16 channel setting patterns (*, 14, 14, *) with a score of 8 or more is shown, and the rest are omitted.

Also in FIG. 15D, the pattern ID for identifying the channel setting pattern is displayed in the first column, and the four point IDs “P1”, “P2”, “P7”, and “P8” are displayed in the second to fifth columns. Each associated channel ID is displayed . Further, on the right side outside the frame of the table, the same channel total time in the channel setting pattern represented by each row is displayed.

  By the way, 1st Embodiment demonstrated as mentioned above with reference to FIGS. 1-15D has the side of the combination optimization problem which combines point ID and channel ID. Considering from the viewpoint of the combinatorial optimization problem, the algorithm of FIG. 11 determines whether there is a trivial preferable solution in step S304, and if no trivial preferable solution is found, the brute-force search is performed in step S309 and thereafter. It is an algorithm to do.

  Forced search is also called exhaustive search, and an optimal solution is always obtained when a solution exists. That is, according to the processing of FIG. 11, it is guaranteed that one or more optimum channel setting patterns are presented among all possible channel setting patterns. However, in the brute force search, a combined explosion occurs depending on the size of the problem. That is, depending on the case, the total number t of channel setting patterns represented by Expression (7) becomes enormous, and the process of FIG. 11 may not be completed in a practical time.

  Therefore, when there is a possibility that the total number t of channel setting patterns becomes enormous, an appropriate channel setting pattern may be obtained by heuristic search. The channel setting pattern presentation device 150 can present an appropriate channel setting pattern to some extent in a practical time even when the total number t of possible channel setting patterns becomes enormous by performing a heuristic search.

  There are various types of heuristic search. In the following, a second embodiment using a greedy algorithm will be described as an example with reference to FIGS. Regarding the configuration of the broadcasting system 100 and the empty channel search process, the second embodiment is common to the first embodiment, and thus the description thereof is omitted.

  FIG. 16 is a flowchart of the pattern determination process in the second embodiment. In the second embodiment, the channel setting pattern presentation device 150 generates a channel setting pattern suitable for local broadcasting in the bus by executing the process of FIG. 16 instead of the process of FIG. 11 in the first embodiment. To do. Then, the channel setting pattern presentation device 150 presents the generated channel setting pattern. The specific method of presentation is various as in the first embodiment.

  As shown in FIG. 16, the channel setting pattern presentation device 150 receives the input of the route ID in step S401, and expands the route information table and the free channel information table based on the route ID in step S402. Details of steps S401 and S402 are the same as steps S301 to S303 in FIG.

Subsequently, in step S403, the channel setting pattern presentation apparatus 150 sets the start point of the route designated in step S401 as “attention point”.
For example, it is assumed that the route ID “1” is input in step S401, and the route information table 205 in FIG. 12 and the free channel information table 206b in FIG. 13B are expanded in step S402. In this case, the starting point of the route R1 = (P1, P2, P7, P8) identified by the route ID “1” is the point P1. Therefore, in step S403, the channel setting pattern presentation device 150 sets the point P1 as a point of interest.

  In step S404, the channel setting pattern presentation device 150 checks the length of the “deemed continuous free section” from the point of interest for each channel in the developed free channel information table 206b. The deemed continuous vacant section may be a section defined by time or a section defined by distance according to the embodiment. In the second embodiment, it is assumed that the deemed continuous vacant section is defined by time.

  FIG. 17 is a diagram for explaining a “deemed continuous empty section” defined in the second embodiment. In FIG. 17, the vertical axis represents the clear level, and the horizontal axis represents time. Similarly to the first embodiment, in the second embodiment, a channel having a clear level of “2” or higher is regarded as an empty channel. That is, the clear level is a level indicating the availability that can be used for local broadcasting, and the value “2” is a threshold that indicates an allowable level for using for local broadcasting.

In FIG. 17, the clear level is less than 2 between times AB, 2 or more between times BC, less than 2 between times CD, 2 or more between times DE, and between times EF Less than 2, 2 or more between times FG, and less than 2 between times GH. Each of the times A to H includes two adjacent point IDs _pj and _{pj + 1 in} the N tuple (p ₁ , p ₂ ,..., P _N ) of the expression (1) representing the designated route. This corresponds to the time when the bus is scheduled to pass through the boundary between the representative areas. In FIG. 17, the boundary between areas is represented by a vertical dotted line.

  For example, in FIG. 17, the length between time AB is that the bus passes through two areas that are adjacent on the route and that are represented by two point IDs corresponding to the clear level of “1”. This corresponds to the length of time it takes. That is, the length between the times A and B is the sum of the reception influence times corresponding to the two point IDs.

  Further, the length between the times BC corresponds to the length of time it takes for the bus to pass through five areas each represented by five consecutive point IDs on the route. The clear levels corresponding to the five point IDs are “2”, “3”, “2”, “3”, and “2” in order, as shown in FIG. The length between time BC is the sum of the reception influence time corresponding to each of the five point IDs.

  The length between the time points CD corresponds to the length of time it takes for the bus to pass through the area represented by one point ID corresponding to the clear level “1”. This corresponds to the length of the reception influence time corresponding to the point ID.

  Similarly, the lengths between times DE, times EF, and FG correspond to the length of reception influence time corresponding to one point ID. Moreover, as shown in FIG. 17, the length between time GH is the sum of the reception influence time each corresponding to three point ID.

The “deemed continuous free section” is a section in which a certain channel can be considered as a continuous free channel. That is, the assumed continuous empty section is based on the assumption that when the clear level falls below “2” for a short time equal to or less than the threshold value T _t , the clear level of “2” or higher is considered to be continuous. This is a section in which clear levels of “2” or higher continue.

The value of the threshold value _Tt represents, for example, the length of time that does not make passengers uncomfortable even if the reception quality temporarily decreases. It is assumed that the value of the threshold value T _t is appropriately determined based on a preliminary experiment or the like.

In the example of FIG. 17, the length between time AB and the length between time GH is longer than the threshold _Tt , and the length between time CD and the length between time EF are less than or equal to the threshold _Tt. It is. Therefore, when the point representing the first area among the five areas corresponding to the time BC is the point of interest, the deemed continuous free section is the section between the times BG.

  From the above definition, for example, when the point representing the earlier area of the two areas corresponding to the time period AB is the point of interest, the length of the deemed continuous free section is 0. . In addition, when the point representing the area corresponding to the time period DE is an attention point, the length of the assumed continuous empty section is the length between the time periods DG.

  Returning to the description of FIG. 16, in step S404, the channel setting pattern presentation device 150 checks the length of the continuous free section only from the point of interest for each channel in the free channel information table 206b as described above. That is, the channel setting pattern presentation device 150 checks the length of the assumed continuous free section that starts corresponding to the area represented by the point of interest for each channel.

Subsequently, in step S405, the channel setting pattern presentation device 150 selects the channel having the longest continuous continuous section examined in step S404.
In step S406, the channel setting pattern presentation device 150 grows the channel setting pattern by associating the selected channel with the point ID of each point in the deemed continuous empty section (including both ends).

  As shown in Expression (2), the channel setting pattern PAT related to the route R defined by the N point IDs is represented by an N tuple of channel IDs. The process of FIG. 16 is a process of sequentially determining N channel IDs from the front.

It is assumed that the jth element (0 ≦ j ≦ N−1) has been determined in the N tuple representing the channel setting pattern PAT. When step S406 is executed for the first time, j = 0. Further, it is assumed that the length of the assumed continuous empty section determined as “longest” in step S405 is the sum of reception influence times corresponding to k (1 ≦ k ≦ N) point IDs. Then, the channel ID selected in step S405 is set as c _sel .

At this time, the processing in step S406 is processing for determining c _sel from the (j + 1) th element to the (j + k) th element of the N tuple representing the channel setting pattern PAT. As a result, the channel setting pattern PAT grows from a state where only the jth element is determined to a state where the (j + k) th element is determined.

  In step S407, the channel setting pattern presentation device 150 determines whether the growth in step S406 has reached a range that can be regarded as arrival at the end point. That is, the channel setting pattern presentation device 150 determines whether or not a channel used for local broadcast has been determined in the range from the start point of the route to the end point of the route or a point that can be regarded as the vicinity of the end point.

For example, the channel setting pattern presentation device 150 uses the threshold value T _e1 (1 <T _e1 ≦ N), and if “T _e1 ≦ (j + k), the growth in step S406 can be regarded as arrival at the end point. It may be determined that the range has been reached. For example, T _e1 = N−1 may be determined.

Alternatively, the channel setting pattern presentation device 150 uses the threshold value _Te2 to indicate “the first point ID · p on the route R = (p ₁ , p ₂ ,..., P _N ) designated in step S401. if the ₁ (j + k) th point ID · p j + sum of the received impact time corresponding to up to _k is T _e2 or more, the growth in step S406 reaches the range that can be regarded as the arrival of the end point It may be judged. For example, the threshold T _e2 may be a value obtained by multiplying the sum of reception influence times corresponding to each of the N point IDs by 0.9 (here, the value “0.9” is merely an example).

If it is determined that “the growth in step S406 has reached a range that can be regarded as arrival at the end point”, the processing in FIG. 16 ends. In this case, the channel setting pattern presentation device 150 associates an arbitrary channel ID (for example, c _sel ) with each of the (j + k + 1) th element to the Nth element of the channel setting pattern PAT, and displays the channel setting pattern PAT. Can be completed.

Conversely, if it is determined that “the growth in step S406 has not reached the range that can be regarded as arrival at the end point”, the process proceeds to step S408.
In step S408, the channel setting pattern presentation device 150 sets a point next to the point where the continuous empty section ends in the channel selected in step S405 as a new attention point. That is, the channel setting pattern presentation device 150 determines the point represented by the (j + k + 1) th point ID · p _{j + k + 1} on the route R = (p ₁ , p ₂ ,..., P _N ) designated in step S401. , Set as a new attention point. Then, the process returns to step S404.

According to the processing of FIG. 16 described above, if the empty channel information table 206b of FIG. 13B is obtained in step S402, for example, the point P1 is first set as the attention point in step S403. If the threshold value _Tt is, for example, 15 seconds, the longest continuous free section only in channel 13 and channel 15 is the longest (that is, 25 + 40 = 65 seconds). Therefore, the channel setting pattern presentation device 150 selects, for example, the channel 13 with the higher clear level in step S405. As a result, in step S406, the first element and the second element of the channel setting pattern are determined to be the channel ID “13”.

  In step S408, the third point P7 is set as a new attention point, and in step S405, the channel 14 is selected. As a result, in step S406, the third element of the channel setting pattern is determined to be the channel ID “14”.

  In step S408, the fourth point P8 is set as a new attention point. In step S405, the continuous free sections of only channel 13 and channel 16 are the longest (60 seconds), and the clear levels of channel 13 and channel 16 are also equal. Therefore, the channel setting pattern presentation device 150 selects, for example, a channel ID “13” that increases the total time of the same channel.

  As a result, in step S406, the fourth element of the channel setting pattern is determined to be the channel ID “13”. That is, the channel setting pattern grows to (13, 13, 14, 13), and the channel setting pattern PAT01 shown in FIG. Then, in step S407, it is determined that “the growth in step S406 has reached a range that can be regarded as arrival at the end point”, and the processing in FIG. 16 ends.

As described above, according to the second embodiment, there is no guarantee that an optimum channel setting pattern can be obtained, but the channel setting pattern presentation device 150 presents a relatively appropriate channel setting pattern without causing a combination explosion. can do. Therefore, in the second embodiment, when the number N of the point IDs that define the route is large because the granularity of the area is fine or the route is long, or the number m _j (1 ≦ 1) of the search target channels at each point. This is suitable when j ≦ N) is large.

  In the example of FIG. 16, the channel setting pattern presentation device 150 grows the channel setting pattern incrementally from the start point to the end point of the path. However, in some embodiments, the channel setting pattern presentation device 150 may grow the channel setting pattern incrementally from the end point of the path to the starting point.

  Alternatively, the channel setting pattern presentation device 150 may select a point near the center of the route as the first point of interest. Then, the channel setting pattern presentation device 150 may grow the channel setting pattern toward the start point and grow the channel setting pattern toward the end point.

  For example, in the example of FIG. 13B, the point P7 near the center of the route may be first selected as the attention point. Then, by the process of growing the channel setting pattern toward the start point, the channel ID “14” is associated with the point P7 and the point P2, and the channel ID “13” is associated with the point P1. Further, for example, a channel ID of “13” is associated with the point P8 by the process of growing the channel setting pattern toward the end point. As a result, the channel setting pattern PAT03 = (13, 14, 14, 13) shown in FIG. 15C or the like is obtained and presented.

  As described above, in the second embodiment, a part of the N points that are continuous on the route (for example, a part starting from the start point, a part starting from the end point, or a part near the center) passes. A channel ID is associated with one or more point IDs corresponding to the partial route. And the channel setting pattern presentation apparatus 150 produces | generates the channel setting pattern which is the final presentation object by growing the pattern which matches channel ID with each one or more point ID corresponding to a partial path | route incrementally.

  Further, according to the second embodiment, as shown in step S403 and step S408, a point adjacent to a partial route that has already been associated with a point ID and a channel ID is set as a point of interest. Then, as in step S <b> 404, the lengths of sections in which the clear level of the same one channel at each of one or more points starting from the attention point satisfies a predetermined criterion are compared between the plurality of channels. Specifically, the “predetermined standard” is a standard that defines, for example, a deemed continuous empty section.

  In the second embodiment, the greedy method is used as an example of the heuristic search. However, the channel setting pattern presentation device 150 generates one or a plurality of channel setting patterns using another heuristic search algorithm. May be. The channel setting pattern presentation device 150 can present the generated one or more channel setting patterns.

  For example, the channel setting pattern presentation apparatus 150 may select the upper U (U> 1) channels from among the channels whose assumed continuous free intervals are not zero in step S405 according to the predetermined upper limit value U. Good. That is, a maximum of U channels with relatively long assumed continuous idle intervals may be selected.

  Then, in step S406, the channel setting pattern presentation device 150 may cause a maximum of U ways of growth for each of the one or more channel setting patterns that are being grown. Further, the channel setting pattern presentation device 150 may narrow down the plurality of channel setting patterns grown in step S406 based on the clear level, the distribution of channel IDs, and the like.

In addition, it is as follows when the common point of said 1st Embodiment and 2nd Embodiment is demonstrated.
In either embodiment, the channel setting pattern presentation device 150 refers to the free channel measurement information table 201 of the storage device 151, narrows down a plurality of potentially possible channel setting patterns, and presents the narrowing down result. Yes.

  That is, in the first embodiment, a process (step S309 in FIG. 11) for generating all potentially possible channel setting patterns, and each of the generated channel setting patterns are evaluated and selected based on the evaluation result. Processing (steps S310 to S315) is included. On the other hand, step S405 of FIG. 16 in the second embodiment is pruning in search, and is a process of narrowing down a plurality of potentially possible channel setting patterns. Therefore, in the second embodiment, only one channel setting pattern may be actually generated by incremental growth, but in the sense of narrowing down a plurality of potentially possible channel setting patterns, the two embodiments are It is common.

  In addition, the channel ID distribution in the tuple of channel IDs in which the channel IDs associated with at least a part of the N point IDs according to the order on the route of each point represented by each point ID are The common point is that it is based on the clear level.

  In other words, in the first embodiment, the distribution of channel IDs in the N tuple of Expression (2) is represented by an index such as the number of channel changes, the same channel continuous time, or the same channel total time. Each channel setting pattern is evaluated by these indices and a score that is a sum of clear levels.

  Further, the deemed continuous vacant section in the second embodiment associates one or more consecutive spot IDs (that is, at least a part of N spot IDs) starting from a point of interest with one identical channel ID. It is also an index to evaluate. In other words, the evaluation of a specific type of distribution, ie, the continuation of the same channel ID, is performed according to the length of the deemed continuous empty section. Further, the deemed continuous empty section is defined by the clear level. Therefore, also in the second embodiment, narrowing down is performed based on the distribution of channel IDs associated with at least some of the N point IDs and the clear level.

The present invention is not limited to the above-described embodiment, and can be implemented with various modifications.
For example, in the above embodiment, for convenience of explanation, various types of information are expressed in a table format, but a data format other than the table format may be employed. Moreover, although the above-described embodiment is an embodiment related to one-segment broadcasting using weak radio waves, the channel setting pattern presenting apparatus 150 may present a channel setting pattern in the same manner for other broadcasting systems that can use a plurality of channels. it can.

Further, as a value indicating the availability as an empty channel, for example, received radio wave intensity may be used instead of the clear level exemplified above.
Further, the channel setting pattern may be evaluated based on the score, the number of channel changes, the same channel continuous time, and the same channel total time as described above, or other criteria may be used. . The method of combining various evaluation criteria is arbitrary depending on the embodiment.

  For example, the channel ID in the above embodiment is an identifier for identifying a physical channel. However, the user of the mobile terminal with TV 140 generally selects a channel using another identifier called “remote control number” instead of the channel ID of the physical channel.

  Therefore, for example, the storage device 151 may store a correspondence table of channel IDs and remote control numbers. Then, channel setting pattern presentation apparatus 150 may calculate the sum of the absolute values of the differences between the remote control numbers at each location where the channel is switched in the channel setting pattern, and use the calculated sum for the evaluation of the channel setting pattern. .

Further, the same channel continuous time in the first embodiment may be replaced with a continuous continuous free space as in the second embodiment. Conversely, in the second embodiment, the same channel continuous time may be used instead of the deemed continuous empty section (that is, the threshold value T _t = 0 may be used).

Of course, the deemed continuous vacant section may be defined and calculated based on the reception influence time as in the second embodiment, or may be defined and calculated based on the reception influence distance. The channel setting pattern presentation device 150, not only the length of a section of clear level falls temporarily below the acceptable level, also based on the frequency with which clearing level falls below the acceptable level temporarily, considered continuous free interval You may judge the length of.

  By the way, in said embodiment, the channel setting pattern for the broadcast in the vehicle which drive | works according to a predetermined timetable, such as a bus and a train, is shown. However, an embodiment relating to a vehicle that may travel on an arbitrary route at an arbitrary time such as a taxi or a private car is also possible.

  For example, it is assumed that a local TV transmitter 110 that also serves as the channel setting pattern presentation device 150 and a car navigation system are loaded on a taxi. For example, the car navigation system can receive a destination input from a driver and set a route. For example, the route may be defined as a tuple of point IDs indicating the positions of intersections.

  While the taxi travels along the set route, the local TV transmitter 110 performs a process similar to that shown in FIG. 9 for a plurality of points on the route (for example, each intersection on the route), so In the measurement information table 201, empty channel measurement information is accumulated.

  If the above processing is carried out in a large number of taxis, it is expected that free channel measurement information will be accumulated at various measurement times at a sufficient number of points so that the data sparseness problem can be ignored. Is done. For example, the car navigation system may set a route based on a destination input from a driver, and may instruct the set route to the channel setting pattern presentation device 150. The channel setting pattern presentation device 150 may present a channel setting pattern based on the instructed route, and the local TV transmitter 110 may perform local broadcasting according to the presented channel setting pattern.

  It is also clear that any vehicle that enters the highway travels along a specific route called a highway. When the vehicle carrying the local TV transmitter 110 runs on the highway, the local TV transmitter 110 loaded on the vehicle performs the processing of FIG. Channel measurement information is accumulated in the free channel measurement information table 201.

  Then, the channel setting pattern presentation device 150 can present a channel setting pattern suitable for local broadcasting in a vehicle traveling on the expressway by referring to the accumulated empty channel measurement information. Therefore, on the highway, the local TV transmitter 110 mounted on an arbitrary vehicle can perform local broadcasting while maintaining good reception quality according to the presented channel setting pattern.

Claims (10)

On the computer,
The availability level of each of the plurality of channels at each of the plurality of points is associated with a point identifier for identifying a plurality of points on the route along which the vehicle moves and a channel identifier for identifying a plurality of channels of the broadcast radio wave. A reference step for referring to storage means for storing;
Narrowing down a plurality of combinable channel setting patterns, each of which is a combination pattern in which the channel identifiers are associated with the plurality of point identifiers representing the plurality of points, respectively, and at least a part of the plurality of point identifiers Distribution of one or more of the channel identifiers in a channel identifier tuple in which the channel identifiers respectively associated with the channel identifiers are arranged in accordance with the order in the path of each point represented by each point identifier, and the availability read by the reference step A refinement step for performing refinement based on gender level;
A presenting step of presenting one or more channel setting patterns obtained as a result of the narrowing step;
Channel setting pattern presentation program for causing the execution. The narrowing-down step includes
A first channel setting pattern in which the same first channel identifier is associated with the point identifier of each of the plurality of points, and a second channel setting pattern in which the same second channel identifier is associated with the point identifier of each of the plurality of points. a first evaluation step of evaluating the bets,
Narrowing down by selecting the first channel setting pattern and the second channel setting pattern which have higher evaluation in the first evaluation step
Including
The first channel identifier and the second channel identifier are each one of a plurality of channel identifiers that respectively identify the plurality of channels . Channel setting pattern presentation program. The narrowing-down step includes
A first generation step of generating the plurality of channel setting patterns;
Each of the plurality of channel setting patterns generated by the first generation step is stored in the storage unit in association with each set of the point identifier and the channel identifier associated with each other in the channel setting pattern. A second evaluation step that evaluates based on each available availability level and a first threshold that indicates an acceptable level;
A selection step of selecting a part of the generated plurality of channel setting patterns based on a result of the second evaluation step;
The channel setting pattern presentation program according to claim 1 , comprising: In the second evaluation step, each channel setting pattern to be evaluated is stored in the storage means corresponding to each set of the spot identifier and the channel identifier that are associated with each other in the channel setting pattern. The availability level is evaluated based on a distribution of availability levels equal to or higher than the first threshold in an availability level tuple arranged according to the order of the corresponding points on the route. The channel setting pattern presentation program according to claim 3. In the second evaluation step, the channel setting pattern to be evaluated,
In a broad sense , the same channel identifier corresponding to the availability level equal to or higher than the first threshold is regarded as continuous even in the channel identifier tuple corresponding to the channel setting pattern. degree, or be continuous in the sense that the continuous
The degree to which the same channel identifier corresponding to the availability level equal to or higher than the first threshold continues in the channel identifier tuple corresponding to the channel setting pattern without interposing another channel identifier therebetween. The higher the continuity of the same channel is, the higher the rating is.
The channel setting pattern presentation program according to claim 3 or 4, characterized in that The same channel continuity is :
The number of times the broad continuity breaks in the channel identifier tuple, with the corresponding non-continuous portion due to one or more channel identifiers having an availability level less than the first threshold being sandwiched in the middle , or,
In the channel identifier tuple, the length of a section in which the same channel identifier corresponding to the availability level equal to or higher than the first threshold is continuous without interposing another channel identifier in between.
Is defined on the basis of,
The channel setting pattern presentation program according to claim 5, wherein: In addition to the length of the section, the same channel continuity is further determined between the two same channel identifiers corresponding to the availability level equal to or higher than the first threshold in the channel identifier tuple. Defined on the basis of the length of the sub-interval between which the same channel identifier or another channel identifier corresponding to the availability level below a threshold of 1 is sandwiched,
The channel setting pattern presentation program according to claim 6. In the second evaluation step, the channel setting pattern to be evaluated is
One or more points identified by one or more of the point identifiers associated with the same channel identifier in the channel setting pattern and corresponding to the availability level equal to or higher than the first threshold , Each of one or more representative areas, the higher the total time it takes for the vehicle to pass, or the longer the total distance traveled by the vehicle in the one or more areas,
The channel setting pattern presentation program according to any one of claims 3 to 7, characterized in that When the computer is loaded on the vehicle and moves on the route, the computer further includes:
A measuring step of measuring the availability level by receiving the broadcast radio wave at each of the plurality of channels at each of the plurality of points;
A writing step for writing the measured availability level in the storage means in association with the point identifier of the point to be measured and the channel identifier of the channel to be measured;
The channel setting pattern presentation program according to any one of claims 1 to 8, wherein the program is executed. The availability level of each of the plurality of channels at each of the plurality of points is associated with a point identifier for identifying a plurality of points on the route along which the vehicle moves and a channel identifier for identifying a plurality of channels of the broadcast radio wave. Storage means for storing;
A narrowing-down means for narrowing down a plurality of combinable channel setting patterns, each of which is a combination pattern in which the channel identifiers are associated with the plurality of point identifiers representing the plurality of points, respectively.
Presenting means for presenting one or more channel setting patterns obtained as a result of narrowing by the narrowing means;
The narrowing-down means includes one or more channels in a channel identifier tuple in which the channel identifiers respectively associated with at least a part of the plurality of point identifiers are arranged according to the order in the path of each point represented by each point identifier. Narrowing down based on the distribution of identifiers and the availability level stored in the storage means;
A channel setting pattern presentation device characterized by the above.

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