JP3865105B2 - Content distribution system and distribution method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technology for transmitting content to a desired base station using a satellite, transmitting the content from this base station to a device installed on a mobile body via radio, and recording / reproducing the data with a reception / reproduction device.
[0002]
[Prior art]
In the field of broadcasting systems, satellite broadcasting systems capable of serving a wide range of areas have been developed, and diversification of broadcasting services is being promoted. In such a satellite broadcasting system, it is possible to provide broadcast signals including video and audio to a wide range of service areas without deploying large-scale broadcasting facilities on the ground as compared with conventional broadcasting systems.
[0003]
[Problems to be solved by the invention]
However, conventional satellite broadcasting systems have a problem that they cannot be received unless they have a relatively large receiving system. That is, the radio wave of satellite broadcasting is weak, and a relatively large receiving antenna is required.
[0004]
A radio wave from a satellite is received by a base station or the like and redistributed via a CATV network. However, a CATV receiving terminal (set top box) or the like is required. Also, it cannot be handled in a mobile environment.
[0005]
The present invention has been made in view of the above circumstances, and an object of the present invention is to enable digital content to be distributed to a mobile body with a small-scale facility.
[0006]
[Means for Solving the Problems]
  In order to achieve the above object, a content distribution system according to the first aspect of the present invention includes:
  A transmission means for transmitting content via a satellite;
  Receive content from the satellite,Encrypt,A base station that transmits via radio (radio wave, light),
  Communicating with the base station via radio, receiving content transmitted from the base station,DecryptAnd reproducing means for reproducing,
  The transmission means includes
  Means for storing the ID of each of said reproduction means;
  Means for transmitting the ID to the base station in a route different from the content in response to an instruction from the outside,
  The base station
  Means for receiving content transmitted from the transmitting means via a satellite;
  Means for accumulating received content;
  Means for detecting reproduction means that has entered the communication area of its own LAN configured wirelessly;
  Means for receiving an ID transmitted by a route different from the content from the transmission means;
  An encryption unit that selects content to be transmitted to the detected reproduction unit from the stored content, and encrypts the selected content using the ID of the reproduction unit received from the transmission unit;
  Means for transmitting the content encrypted using the ID to the detected reproduction means via the LAN,
  It is characterized by that.
[0007]
  The transmission means further includes means for transmitting the content in an encrypted state and transmitting a decryption key for decrypting the encrypted content to the base station together with the ID. Well,
  The base station may comprise means for receiving the decryption key together with the ID,
  The encryption means decrypts the content selected for transmission to the reproduction means using the received decryption key, and then encrypts the content using the ID of the reproduction means received from the transmission means. May be.
[0008]
  A content distribution system according to the second aspect of the present invention includes:
  A transmission means for transmitting content via a satellite;
  Receive content from the satellite,Encrypt,A base station transmitting via radio,
  Communicating with the base station via radio, receiving content transmitted from the base station,DecryptAnd reproducing means for reproducing,
  The transmission means includes means for transmitting the ID of the reproduction means to the base station via a route different from the content,
  The base station
  A designation means for designating a reproduction means of a transmission destination;
  Means for receiving the content and ID from the transmission means;
  Encryption means for encrypting the received content using the ID of the reproduction means designated by the designation means;
  Means for transmitting the content encrypted using the ID to the reproduction means designated by the designation means.
  It is characterized by that.
[0009]
  As a method for specifying the transmission destination, for example, there are a method of directly inputting the address of the transmission destination, a method of recording the address on an ID card and the like, a method of reading the address, and a method of specifying by performing mutual authentication by communication .
  The transmission means further includes means for transmitting the content in an encrypted state and transmitting a decryption key for decrypting the encrypted content to the base station together with the ID. Well,
  The base station may comprise means for receiving the decryption key,
  The encryption means may decrypt the received content using the received decryption key and then encrypt the content using the reproduction means ID designated by the designation means.
[0010]
  The content distribution system according to the third aspect of the present invention is:
  A transmission means for transmitting content via a satellite;
  Receive content from the satellite,Encrypt,A base station transmitting via radio,
  Communicating with the base station via radio, receiving content transmitted from the base station,DecryptAnd reproducing means for reproducing,
  The transmission means transmits the content in an encrypted state, and transmits a decryption key for decrypting the encrypted content to the base station through a route different from the content. Further comprising
  The base station comprises means for receiving the decryption key through a route different from the content, and means for receiving an encryption key for re-encrypting the content from the reproduction means, and the content received from the satellite Is decrypted using the received decryption key, re-encrypted using the received encryption key, and then transmitted to the playback means.
  It is characterized by that.
[0011]
For example, the base station includes a unit connected to the transmission unit and requesting the transmission unit to transmit desired content. In this case, the transmission means transmits the requested content via the satellite according to the request from the base station.
[0012]
There may be further provided charging means for recording charging information of each of the reproducing means. In this case, for example, the base station inquires of the charging unit, and when the charging unit is notified that the charging process has been completed, transmits the content to the playback unit. In response to the inquiry from the base station, a notification indicating whether or not the accounting process has been completed is transmitted.
[0013]
Further, the transmitting means and the base station are connected by a terrestrial network different from the communication using the satellite, the base station inquires to the charging means via the terrestrial network, and the charging means In response to the inquiry from the base station, a notification indicating whether or not the billing process is completed may be transmitted via the terrestrial network.
[0014]
For example, the base station stores the content together with the encryption key in an encrypted state. When transmitting the content, the playback unit is authenticated, the playback unit is authenticated, the content encryption is decompressed, and the decompressed content is encrypted and transmitted by the playback unit. . The reproduction means preferably stores the received content without decrypting it. In this case, reproduction is performed while decoding at the time of reproduction.
[0015]
The base station packetizes and transmits data, and the in-vehicle device receives the data transmitted from the base station, confirms the received data, and resends the corresponding data if there is a defect. Means for requesting the base station may be provided.
[0016]
  The reproducing means may include means for transmitting radio waves,
  The base station
  Arranged at regular intervals,Said reproduction meansA pair of antennas each receiving radio waves transmitted by
  Demodulating means for demodulating each signal represented by radio waves respectively received by the pair of antennas;
  Obtain the phase difference of each demodulated signal, based on the obtained phase difference,Reproduction meansWhether or not the position is within a predetermined rangeAnd may further comprise means for,
  The base station has the playback meansWhen it is determined that the content is within the predetermined range, the content isReproduction meansSend toYou may do.
[0017]
  In addition, the first of the present invention4The reception / redistribution system related to
  Means for receiving encrypted content transmitted from a satellite;
  Storage means for storing received content;
  A decryption key for decrypting the content, and the contentTo deliver to the mobile station that is the delivery destinationMeans for receiving an encryption key for re-encryption through a communication route different from the content transmission;
  Means for decrypting the content stored in the storage means using the decryption key, further encrypting the content using the encryption key, and then transmitting to the mobile station via radio;
  It is characterized by providing.
[0018]
  The reception / redistribution system includes means for requesting content by designating content to a content transmission source, and means for receiving a content decryption key from the content transmission source in response to the request.
[0020]
  In order to achieve the above object, the present invention5The content distribution method related to
  Send the encrypted content from the transmitting station via the satellite to the receiving station,
  From the transmitting station, a decryption key for decrypting the content, and the contentThe receiving stationEncrypt againAnd distribute it to the terminal to which the content is distributedTo doShould be used by the receiving stationSending the encryption key to the receiving station through a communication route different from the content transmission,
  Receiving the content, the decryption key and the encryption key at the receiving station, decrypting the content using the decryption key, further encrypting the content using the encryption key, and transmitting the wireless network via the wireless network;
  In the terminal near the receiving station, the content transmitted via the wireless network is received and recorded on a recording medium.
It is characterized by that.
  The terminal may transmit radio waves,
  The receiving station receives the radio waves by a pair of antennas arranged at regular intervals, demodulates each signal represented by the received radio wave, and obtains a phase difference between these signals. Based on the phase difference, it is determined whether or not the position of the terminal is within a predetermined range. When it is determined that the terminal is within the predetermined range, the content may be transmitted.
[0021]
  The receiving station receives and accumulates content transmitted from the transmitting station via a satellite,
  Receive the content at the stored receiving station, send it over the wireless network,
  Terminals near the receiving stationButReceive content transmitted over a wireless network.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a digital content distribution system of the present invention will be described in detail with reference to the drawings, taking as an example the case of distributing music data.
[0023]
This digital content distribution system transmits music data in advance to a plurality of ground base stations by satellite broadcasting, transmits music data from the base station to an in-vehicle acoustic device by wireless LAN, and the acoustic device receives the music. It is a system that records in memory and plays back.
[0024]
FIG. 1 shows the configuration of a satellite broadcasting system according to a first embodiment of the present invention. As shown in the figure, this satellite broadcasting system includes a content provider 10, a transmission station 20, a satellite 30, a plurality of base stations 40, and an in-vehicle device 50.
[0025]
The content provider 10 supplies digital content (in this embodiment, digital music) to the transmission station 20 in accordance with a preset program.
[0026]
FIG. 2 shows the configuration of the content provider 10. As illustrated, the content provider 10 includes a content DB (database) 101 that stores a large number of digital contents, a registered member DB 102 that records information about registered users, and a content server 103.
[0027]
The content DB 101 stores a song identification code (ID), a song name, encrypted music data, and an encryption key.
[0028]
The registered member DB 102 stores member identification numbers (IDs), information such as names and addresses, device IDs of devices owned by members, and billing information.
[0029]
The content server 103 is connected to the content DB 101 and the registered member DB 102 via a LAN, and further connected to the transmitting station 20 via a dedicated line, and further, a terrestrial line such as the Internet, public line (wired / wireless), etc. Is connected to the base station 40 via The content server 103 reads the music data from the content DB 101 according to the program (program guide) set by itself, transmits the encrypted music content to the transmitting station 20, and transmits the encryption key to the base station via the terrestrial line. Transmit to station 40. Further, the content server 103 notifies the base station 40 of data indicating whether or not the user is a registered member in response to an inquiry specifying the user from the base station 40.
[0030]
The transmitting station 20 transmits the music data supplied from the content server 103 toward the satellite 30 at a predetermined frequency.
The satellite 30 is a stationary satellite called a BS satellite, a CS satellite, or the like that orbits the equator orbit, and is a channel such as a Ku-band broadcast signal transmitted from the transmission station 20 via an upstream transmission path. A signal is received, frequency-converted to S band, and transmitted to the service area on the ground via a downlink transmission path.
[0031]
The base station 40 is a system installed at a gas station (GS) in the service area of the satellite 30, and as shown in FIG. 3, a receiving antenna 401, a demodulator 402 that demodulates a received signal, and a demodulator It comprises a large-capacity memory 403 such as a hard disk for storing data, a GS server 404, an operation panel 405, and a wireless LAN device 406.
[0032]
The receiving antenna 401 receives radio waves transmitted from the satellite 30.
The demodulator 402 demodulates the signal received by the receiving antenna 401.
The large-capacity memory 403 is composed of a hard disk device or the like, and stores music data (encrypted) and an encryption key in association with each other.
[0033]
The GS server 404 is for controlling the operation of the entire base station 40 installed at each gas station, and is connected to the demodulator 402 and a terrestrial line such as the Internet. The GS server 404 stores the encrypted music data decrypted by the demodulator 402 and the encryption key in the large capacity memory 403 in association with each other. In response to an instruction from the operation panel 405, the GS server 404 inquires the content provider 10 for charging information via the terrestrial line. Download to the in-vehicle device 50 via the wireless LAN device 406.
[0034]
The operation panel 405 includes a plurality of operation keys and the like, and instructs the GS server 404 for various instructions.
The wireless LAN device 406 includes a LAN cable connected to the GS server 404 and a wireless LAN adapter connected to the LAN cable via a hub or the like, and configures a LAN wirelessly with the in-vehicle device 50. Note that the wireless medium is arbitrary, and normal radio waves, light (for example, IrDa), Bluetooth, and the like can be used.
[0035]
The in-vehicle device 50 is configured by so-called car audio or the like, is placed on a vehicle or the like, receives music data from the base station 40 via a wireless LAN, and stores it in a detachable semiconductor memory. Furthermore, it is an apparatus for playing back music stored in the semiconductor memory as appropriate.
[0036]
As shown in FIG. 4, the in-vehicle device 50 includes a memory I / O 501, an internal memory 502, a security circuit 503, a CODEC 504, a D / A 505, an A / D 506, a first microprocessor 507, a display A panel 508, a key panel 509, an external communication unit 510, a second microprocessor 511, a CD driver 512, a radio circuit 513, a D / A 514, an amplifier 515, and a speaker 516 are provided.
[0037]
An external memory 520 composed of a rewritable nonvolatile memory (flash memory or the like) is detachably attached to the memory I / O 501, and data is written to or read from the external memory 520. The memory I / O 501 is also connected to an internal memory (flash memory) 502, and writes data to the internal memory 502 or reads stored data.
[0038]
The internal memory 502 is fixedly arranged inside the in-vehicle device 50, and stores a unique device ID of this device in part.
The security circuit 503 encrypts data to be written to the external memory 520 and the internal memory 502, and decrypts the read data.
The CODEC 504 is a compression / decompression circuit that decodes output data and encodes input data.
[0039]
The D / A 505 converts the output digital data into an analog signal.
The A / D 506 converts an input analog signal into digital data.
The first microprocessor 507 is for controlling the operation of the entire vehicle-mounted device 50, and is composed of a CPU having a built-in ROM storing a program.
[0040]
The display panel 508 includes a liquid crystal display panel, a fluorescent display panel, and the like, and displays various data.
The key panel 509 is operated by a user and inputs various instructions to the in-vehicle device 50.
The external communication unit 510 performs wireless communication with the base station under the control of the first microprocessor 507.
[0041]
The second microprocessor 511 is a processor for sound control, and controls the CD driver 512 and the radio circuit 513 and outputs the reproduced sound through the speaker 516 under the control of the first microprocessor 507. .
The D / A 514 converts the reproduction digital data output from the second microprocessor 511 into an analog signal.
The amplifier 515 amplifies the analog signal output from the D / A 514 and emits the sound via the speaker 516.
[0042]
Next, the operation of the content distribution system configured as described above will be described.
(Distribution of music data)
First, processing until music data is stored in the large-capacity memory 403 of the base station 40 will be described.
The content DB 101 stores encrypted music data together with its encryption key.
The content server 103 reads the encrypted content according to the program table created in advance and transmits it to the transmitting station 20.
[0043]
The transmitting station 20 modulates the music data supplied from the content server 103, assigns it to an empty slot, and transmits it to the satellite 30 at a predetermined frequency.
[0044]
The satellite 30 converts the frequency of the transmission signal from the transmission station 20 and transmits it to the ground.
The base station 40 installed in the gas station located in the area of the satellite 30 receives this by the receiving antenna 401 and demodulates the received signal by the demodulator 402. The GS server 404 stores the demodulated music data in the large capacity memory 403.
[0045]
On the other hand, the content server 103 transmits the decryption key of the transmitted music data to each base station 40 via the terrestrial line. Each base station registers the received decryption key in the large capacity memory 403 in association with the music data.
[0046]
For example, the music data is stored in the large-capacity memory 403 of each base station 40 by repeating the above process at midnight when the communication traffic is small.
[0047]
(Download music data to in-vehicle device)
1) The base station 40 installed at the gas station periodically transmits a signal for inquiring whether there is a new in-vehicle device (communication terminal) 50 from the wireless LAN device 406 into the communication area. The presence or absence is always determined.
[0048]
Suppose a vehicle stops at this gas station under such circumstances.
When the vehicle approaches the premises of the gas station, the external communication unit 510 of the in-vehicle device 50 detects a wireless signal from the wireless LAN device 406 and notifies the first microprocessor 507. The first microprocessor 507 transmits a response to the base station 40 via the external communication unit 510.
As a result, the new in-vehicle device 50 is recognized by the base station 40, and thereafter, data communication between the in-vehicle device 50 and the base station 40 becomes possible.
[0049]
2) When a user of a vehicle entering a gas station wants to download music data to his in-vehicle device 50, the user accesses his home page provided by the content provider 10 using his mobile terminal (for example, a mobile phone). Then, specify the gas station ID and the song number (or station code).
[0050]
The content server 103 determines whether or not the caller is a registered member based on the telephone number of the caller. If the content server 103 determines that the caller is a registered member, the content server 103 updates the charging data of the registered member. For example, if you charge 300 yen each time you download one song, 300 yen is added to the accounting data. Subsequently, the content server 103 transmits an encryption key for decrypting the designated song and the device ID of the user to the instructed GS server 404 via the ground system line. When the above process ends, the content server 103 transmits a message such as “Download is possible” to the mobile terminal.
[0051]
In response to this message, the user designates the song name to the person in charge at the gas station and requests download. The person in charge designates a song from the operation panel 405 and instructs download.
Then, the GS server 404 first determines whether or not a decryption key for the designated song has been received. If not received, an error is notified.
On the other hand, if it has been received, it enters a standby state.
[0052]
The user operates the key panel 509 to specify a download destination memory (internal memory 502 or external memory 520) and operates a “download” button. In response to the operation of the “download button”, the first microprocessor 507 reads the device ID from the internal memory 502 via the security circuit 503 and the memory I / O 501, and download request command via the external communication unit 510. At the same time, it transmits to base station 40.
[0053]
The GS server 404 of the base station 40 receives the download request command and the device ID via the wireless LAN device 406, and decrypts the specified music data using the decryption key. Subsequently, the decrypted music data is encrypted using the device ID that has received it. Further, the encrypted music data is transmitted in packet units to the in-vehicle device 50 via the wireless LAN device 406.
[0054]
The first processor 507 of the in-vehicle device 50 sequentially receives packets via the external communication unit 510, performs CRC check, etc., and then reconstructs data. The reconstructed data is stored in a designated memory (internal memory 502 or external memory 520).
[0055]
3) The music data requested by the user may not be stored in the large-capacity memory 403 of the base station 40. In such a case, the person in charge at the gas station designates the song name and transmits a request to the content server 103. In response to this request, the content server 103 sends the music data with the address of the base station 40 that issued the request as the destination. The transmitting station 20 broadcasts this music data, and the data reaches all the base stations 40 in the jurisdiction area of the satellite 30. Since a specific address is set as the destination, the other base stations 40 use this data. Do not receive.
[0056]
On the other hand, the content server 103 transmits the decryption key of the music data to the GS server 404 via the terrestrial line. The GS server 404 stores the music data received by the receiving antenna 401 and demodulated by the demodulator 402 in association with the encryption key received via the terrestrial system in the large capacity memory 403.
The subsequent operation is the same as described above.
[0057]
(Leave from LAN)
When the download is completed and the vehicle leaves the gas station, the in-vehicle device 50 cannot communicate with the wireless LAN device 406. The GS server 404 deletes the in-vehicle device 50 that has not responded to polling for a certain period or more from the component table, assuming that it has left the wireless LAN device 406.
[0058]
(Playing back downloaded music data)
When the user wants to play the downloaded music, the user instructs to display a list of music data stored in the internal memory 502 or the external memory 520 by operating the key panel 509.
In response to this instruction, the first microprocessor 507 accesses the internal memory 502 or the external memory 520 via the memory I / O 501 and the security circuit 503, and the music corresponding to the table of contents from the TOC (Table Of Contents) area. The list is read out and displayed on the display panel 508.
The user selects an arbitrary song by key operation and designates playback.
[0059]
In response to this instruction, the first microprocessor 507 reads out the designated music piece data from the internal memory 502 or the external memory 520 via the memory I / O 501, decrypts it with the security circuit 503, and further, the CODEC 504 To decode (decompress) and output. This data is converted into an analog signal by the D / A 505 and output to the earphone plug. Therefore, it is possible to listen to music reproduced using the earphone. It is also possible to extract the digital data output from the CODEC 504 directly from the DigitalOut terminal.
[0060]
Further, the reproduced digital data is supplied to the second microprocessor 511 via the first microprocessor 507, is appropriately D / A converted, amplified, and emitted from the vehicle-mounted speaker.
[0061]
As described above, according to this embodiment, when a vehicle stops at a gas station, music data is downloaded from a base station to an in-vehicle device via a wireless LAN, and recorded and reproduced on a recording medium. be able to. Therefore, the in-vehicle device does not require a large-scale device that receives radio waves from a satellite, and music data can be stored with a small and light device.
[0062]
In addition, since the data is transmitted from the satellite 30 to the plurality of base stations 40 in a broadcast format, the communication cost can be reduced. In addition, since the decryption key is transmitted to each GS server 404 via a terrestrial line of a route different from the broadcast, it is possible to prevent a situation where the encryption key leaks and the music data is illegally decrypted.
[0063]
In addition, music data can be transmitted to each GS server 404 in a batch format mainly during a low traffic period such as midnight.
[0064]
The present invention is not limited to the above embodiment, and various modifications and applications are possible.
For example, in the above embodiment, the charging process is performed one by one at the time of downloading. However, the prepaid method is used, a predetermined fee is paid in advance, an appropriate frequency is purchased, and this frequency is reduced to 0 for each download. Until then, it may be withdrawn.
[0065]
In this case, for example, a prepaid card is purchased at a gas station. In this prepaid card, a card ID and a password derived from the card ID by a special arithmetic expression are recorded. This ID, password, and frequency are registered in advance in the charging database of the content provider. The user inputs this ID and password on the input form on the home page provided by the content DB. When the content provider verifies the input ID and password and determines that the content is correct, the content provider accepts a download request. Each time one song is downloaded, the predetermined frequency is withdrawn and the download is permitted until the frequency becomes zero.
[0066]
In addition, the number of downloads may be unlimited by paying a certain amount every month or year. In this case, it is only necessary to determine whether or not a fee is paid when determining whether or not to permit downloading.
[0067]
In addition, the said base station is not limited to a gas station, It can be installed in various places. For example, it is desirable that the vehicle is installed in an area where a vehicle stops relatively, such as a convenience store, a family restaurant, a car shop, and a service area in the service area of the satellite 30.
[0068]
In the above embodiment, when a base station is arranged at an adjacent gas station, it becomes a problem as to which base station the in-vehicle device communicates with.
In this case, for example, when each vehicle is in its own site, it is reasonable to communicate with the vehicle. Therefore, for example, a position detection device having the configuration shown in FIG. 5 is arranged, the position of the vehicle is determined, and if the determined position is within its own site, communication is performed.
[0069]
The configuration shown in FIG. 5 includes a pair of antennas 451 and 452, a pair of high frequency circuits 461 and 462, a pair of CDMA demodulators 471 and 472, a phase comparator 481 and 482, and a pair of antennas 451 and 452. The time difference measuring circuit 491 is provided.
[0070]
The radio waves emitted from the in-vehicle device 50 are received by the pair of antennas 451 and 452 and converted into intermediate frequencies by the pair of high frequency circuits 461 and 462, respectively. Subsequently, the CDMA demodulators 471 and 472 demodulate the phase modulation signal.
[0071]
Phase comparators 481 and 482 obtain the phase difference between the reference clock and the demodulated signal, respectively. Finally, the time difference measurement circuit 491 obtains the time difference between the signals output from both systems, and the position of the vehicle (on-vehicle device) can be specified from this time difference. And the situation where the adjacent several base station 40 communicates with one vehicle can be prevented because the specified position communicates only with the vehicle-mounted apparatus 50 in an own site.
Note that a signal designating one of the adjacent base stations 40 may be transmitted from the in-vehicle device 50 so that only the designated base station 40 communicates with the in-vehicle device 50.
[0072]
In mobile communication, some communication information may be lost. In normal conversations, missing data is not a problem. However, in the case of distribution of digital content such as music data based on billing, even a part of the content is a big problem. Therefore, the operation when data loss occurs will be described below with reference to FIG.
[0073]
First, a request for downloading music data is issued from the in-vehicle device 5 (S1). In response to this request, the GS server 404 adds a checksum to the transmission target data, generates data for one packet, for example, 1 MB data, and transmits it (S2). The first microprocessor 507 of the in-vehicle device 50 performs a sum check on the received data (S3). Here, when an error is detected, the error bit is corrected normally. However, in this embodiment, a retransmission is requested to the GS server 404 (S4). In response to this request, the GS server 404 retransmits the data (S5).
[0074]
On the other hand, if it is determined that the data is normal as a result of the sum check, the GS server 404 is requested to transmit data for the next one packet (S6).
Thereafter, the same operation is repeated.
[0075]
(Second Embodiment)
Next explained is the second embodiment of the invention.
FIG. 7 shows the configuration of a content distribution system according to the second embodiment of the present invention.
[0076]
As illustrated, this distribution system includes a content server 1010, a transmission station 1020, a satellite 1030, a plurality of receiving devices (base stations) 1040, a charging server 1050, and an in-vehicle device 1060.
[0077]
The content server 1010 compresses the content that has already been transmitted or will be transmitted, and further stores the encrypted content. The content server 1010 transmits (broadcasts) the content to be transmitted to each receiving device 1040 through the transmitting station 1020 and the satellite 1030 in an available time zone such as from midnight / early morning (for example, from 1 am to 4 am). .
[0078]
Each receiving device 1040 includes a local server 1140. The local server 1140 includes a large-capacity recording medium such as a hard disk HDD that stores received content (compressed and encrypted).
[0079]
A wired LAN 1141 is connected to the local server 1140, and a wireless LAN access point 1142 is connected to the wired LAN 1141. Furthermore, readers / writers 1143 and 1144 for reading data recorded on the ID card or writing data on the ID card are connected to the local server 1140. Furthermore, the local server 1140 is connected to the billing server 1050 via a public telephone line.
[0080]
Next, a method for distributing content using the distribution system having the configuration shown in FIG. 7 will be described.
[0081]
  The content server 1010 compresses the content that has already been transmitted or will be transmitted, and further stores the encrypted content. The content server 1010 transmits the content to be transmitted to each receiving device 10 through the satellite 1030 in a vacant time zone such as midnight.4Transmit (broadcast) to 0.
[0082]
Each receiving device 1040 stores content (compressed and encrypted) transmitted via the satellite 1030 in the hard disk HDD in the local server 1140.
[0083]
When downloading music data from the local server 1140 to its own playback device, the user performs membership registration in advance and receives an ID card. In this ID card, a unique ID number, personal information and billing information are registered. The same information is also registered in billing server 1050. Furthermore, information (address information) for specifying the in-vehicle device 1060 is set in the ID card.
[0084]
In the scene of downloading music data, the user designates a song to be downloaded and gives his / her ID card to the person in charge at the gas station. The person in charge attaches the ID card to the reader / writer 1143 and inputs the designated music piece to the local server 1140.
[0085]
The local server 1140 reads the ID card recording information via the reader / writer 1143, and transmits the ID information, balance information, and song name (or song code) of the read information to the billing server 1050 via the telephone line. To do.
[0086]
The billing server 1050 checks whether or not the received ID information is valid by comparing the received information with the information registered in itself, and if it is valid, the billing server 1050 releases the encryption of the designated song. Send the decryption key to the local server.
The local server 1140 decrypts the music data using the received descrambling key, and further encrypts it using the ID of the in-vehicle device 1060. Then, based on the information read from the ID card, the destination address of the LAN is designated and transmitted to the in-vehicle device 1060. The in-vehicle device 1060 can store the received music data in a recording medium and reproduce it as in the first embodiment.
[0087]
The user charges (deposits) a fixed amount on the ID card at an arbitrary gas station. The local server 1140 notifies the charging server of the ID information and the deposit amount (which may be a fixed amount or an arbitrary amount). The billing server 1050 performs processing for adding the notified amount to the balance.
According to this method, it is possible to easily identify the person and specify the music data transmission destination.
[0088]
The ID card may have charging information, or the charging server may have charging information. For example, only ID information may be recorded on the ID card, and the billing information on the billing server may be updated each time a download is made. Alternatively, the charging information may be provided on the ID card, and the download may be permitted only when there is a remaining amount from which this information can be downloaded. From the viewpoint of fraud prevention, it is desirable to register some billing information in the billing server 1050.
[0089]
The first and second embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments.
For example, in the above-described embodiment, an example in which a semiconductor storage device (flash memory) is used as the recording medium has been described, but the recording medium is arbitrary. For example, MD, MO, CD-R, etc. may be used.
[0090]
In the first embodiment, music data that is not stored in the large-capacity memory 403 of the base station 40 is transmitted from the content provider 10 by the broadcast method, but may be transmitted by a terrestrial line.
[0091]
In the above-described embodiment, an example of music data is shown as downloadable content. However, the present invention can be applied to various digital content data distribution such as downloading car navigation map data.
[0092]
  Further, the above-described system configuration and circuit configuration are examples, and are not limited to these. For example, the configuration of the in-vehicle device shown in FIG. 4 is based on a conventional car audio, but for example, as shown in FIG. 8, a semiconductor memory and a magnetic disk are used as main recording media. Also good.
  In addition, a method for specifying content, a method for encrypting content, and a method for decrypting can be arbitrarily selected.is there. For example, as a method for designating content to be downloaded, a method has been described that considers a vehicle-mounted device with a limited display area and number of keys. For example, a relatively large screen display panel 508 and a key panel having a large number of keys If 509 can be secured, it is naturally possible to directly specify the download desired music or perform billing processing by performing wireless communication between the in-vehicle device 50 and the base station 40.
[0093]
【The invention's effect】
As described above, according to the present invention, music data is distributed to a base station using satellite broadcasting, and is further transmitted wirelessly to a mobile station that stops near the base station and recorded on a recording medium. can do.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a content distribution system according to an embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a content provider.
FIG. 3 is a diagram showing a configuration of a base station installed at a gas station or the like.
FIG. 4 is a diagram illustrating a configuration of an in-vehicle device.
FIG. 5 is a diagram illustrating an example of a configuration for detecting the position of an in-vehicle device.
FIG. 6 is a diagram illustrating an example of a packet transmission procedure.
FIG. 7 is a diagram showing an overall configuration of a content distribution system according to a second embodiment of the present invention.
FIG. 8 is a diagram illustrating another example of the configuration of the in-vehicle device.
[Explanation of symbols]
10 Content provider
20 Transmitting station
30 satellites
40 base stations
50 In-vehicle device

Claims (16)

A transmission means for transmitting content via a satellite;
A base station that receives content from the satellite, encrypts it, and transmits it via radio;
A communication unit configured to perform communication with the base station via wireless, receive content transmitted from the base station, decode and reproduce the content, and
The transmission means includes
Means for storing the ID of each of said reproduction means;
Means for transmitting the ID to the base station in a route different from the content in response to an instruction from the outside,
The base station
Means for receiving content transmitted from the transmitting means via a satellite;
Means for accumulating received content;
Means for detecting reproduction means that has entered the communication area of its own LAN configured wirelessly;
Means for receiving an ID transmitted by a route different from the content from the transmission means;
An encryption unit that selects content to be transmitted to the detected reproduction unit from the stored content, and encrypts the selected content using the ID of the reproduction unit received from the transmission unit;
Means for transmitting the content encrypted using the ID to the detected reproduction means via the LAN,
A content distribution system characterized by the above. The transmission means further transmits the content in an encrypted state, and further includes means for transmitting a decryption key for decrypting the encrypted content to the base station together with the ID.
The base station comprises means for receiving the decryption key together with the ID;
The encryption means decrypts the content selected for transmission to the reproduction means using the received decryption key, and then encrypts the content using the ID of the reproduction means received from the transmission means.
The content distribution system according to claim 1. A transmission means for transmitting content via a satellite;
A base station that receives content from the satellite, encrypts it, and transmits it via radio;
A communication unit configured to perform communication with the base station via wireless, receive content transmitted from the base station, decode and reproduce the content, and
The transmission means includes means for transmitting the ID of the reproduction means to the base station via a route different from the content,
The base station
A designation means for designating a reproduction means of a transmission destination;
Means for receiving the content and ID from the transmission means;
Encryption means for encrypting the received content using the ID of the reproduction means designated by the designation means;
Means for transmitting the content encrypted using the ID to the reproduction means designated by the designation means. A content distribution system comprising: The transmission means further transmits the content in an encrypted state, and further includes means for transmitting a decryption key for decrypting the encrypted content to the base station together with the ID.
The base station comprises means for receiving the decryption key;
The encryption means decrypts the received content using the received decryption key, and then encrypts the content using the reproduction means ID designated by the designation means.
The content distribution system according to claim 3. A transmission means for transmitting content via a satellite;
A base station that receives content from the satellite, encrypts it, and transmits it via radio;
A communication unit configured to perform communication with the base station via wireless, receive content transmitted from the base station, decode and reproduce the content, and
The transmission means transmits the content in an encrypted state, and transmits a decryption key for decrypting the encrypted content to the base station through a route different from the content. Further comprising
The base station comprises means for receiving the decryption key through a route different from the content, and means for receiving an encryption key for re-encrypting the content from the reproduction means, and the content received from the satellite Is decrypted using the received decryption key, re-encrypted using the received encryption key, and then transmitted to the playback means.
A content distribution system characterized by that. The base station is connected to the transmission means, and comprises means for requesting the transmission means to transmit desired content;
6. The content distribution system according to claim 1, wherein the transmission unit transmits the requested content via the satellite according to a request from the base station. Charging means for recording charging information of each of the playback means;
The base station inquires to the billing unit, and when the billing unit is notified that the billing process is completed, transmits the content to the playback unit,
The billing means transmits a notification indicating whether or not the billing process is completed in response to the inquiry from the base station.
The content distribution system according to claim 1, wherein the content distribution system is a content distribution system. The transmission means and the base station are connected by a terrestrial network different from the communication using the satellite,
The base station inquires to the charging means via the terrestrial network,
The billing means transmits a notification indicating whether or not the billing process is completed in response to the inquiry from the base station via the terrestrial network.
The content distribution system according to claim 7. The base station stores the content in an encrypted state together with an encryption key,
After authenticating the playback means, authenticating the playback means, decompressing the content encryption, encrypting and transmitting the decompressed content in a manner that can be played back by the playback means,
The reproduction means stores the received content;
The content distribution system according to any one of claims 2, 4, and 5. The base station transmits data in packets,
The reproducing means includes means for receiving data transmitted from the base station, confirming the received data, and requesting the base station to retransmit the corresponding data if a part is defective,
The content distribution system according to any one of claims 1 to 9, wherein The reproducing means includes means for transmitting radio waves,
The base station
A pair of antennas arranged at regular intervals, each receiving radio waves transmitted by the reproduction means ;
Demodulating means for demodulating each signal represented by radio waves respectively received by the pair of antennas;
Each obtains a phase difference of the demodulated signal based on the phase difference obtained, and means the position of the reproducing means determines whether or not within a predetermined range, further comprising a
The base station, when said reproducing means is determined to be within a predetermined range, that sends the content to the reproduction unit via the radio,
The content distribution system according to claim 1, wherein the content distribution system is a content distribution system . Means for receiving encrypted content transmitted from a satellite;
Storage means for storing received content;
Means for receiving a decryption key for decrypting the content and an encryption key for re-encrypting the content for distribution to the mobile station that is the distribution destination through a communication route different from the content transmission When,
Means for decrypting the content stored in the storage means using the decryption key, further encrypting the content using the encryption key, and then transmitting to the mobile station via radio. Receiving / redistribution system. The reception / redistribution system includes means for requesting content by designating content to a content transmission source,
13. The reception / redistribution system according to claim 12, further comprising means for receiving a content decryption key from a content transmission source in response to a request. Send the encrypted content from the transmitting station via the satellite to the receiving station,
A decryption key for decrypting the content from the transmitting station, and a cipher to be used by the receiving station in order for the receiving station to re-encrypt the content and distribute it to the terminal to which the content is distributed A key is transmitted to the receiving station via a communication route different from the content transmission;
The receiving station receives the content, the decryption key, and the encryption key, decrypts the content using the decryption key, further encrypts the content using the encryption key, and then transmits the content via the wireless network.
In the terminal near the receiving station, the content transmitted via the wireless network is received and recorded on a recording medium.
The content delivery method characterized by the above-mentioned. The terminal transmits radio waves,
The receiving station receives the radio waves by a pair of antennas arranged at regular intervals, demodulates each signal represented by the received radio wave, and obtains a phase difference between these signals. Based on the phase difference, it is determined whether or not the position of the terminal is within a predetermined range, and when it is determined that the terminal is within the predetermined range, the content is transmitted.
The content distribution method according to claim 14, wherein: In the receiving station,
Receive and store content transmitted from the transmitting station via satellite,
Receive the stored content, send it over the wireless network,
A terminal in the vicinity of the receiving station receives content transmitted via a wireless network;
The content distribution method according to claim 14 , wherein:

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