EP0748073A1 - Nachrichtenübertragungsprotokoll für Zugangskontrolle für RDS-Anwendung, bzw. Übertragungs- und Empfangsvorrichtung dafür - Google Patents

Nachrichtenübertragungsprotokoll für Zugangskontrolle für RDS-Anwendung, bzw. Übertragungs- und Empfangsvorrichtung dafür Download PDF

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Publication number
EP0748073A1
EP0748073A1 EP96401198A EP96401198A EP0748073A1 EP 0748073 A1 EP0748073 A1 EP 0748073A1 EP 96401198 A EP96401198 A EP 96401198A EP 96401198 A EP96401198 A EP 96401198A EP 0748073 A1 EP0748073 A1 EP 0748073A1
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Prior art keywords
rds
messages
message
access control
encrypted
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EP96401198A
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English (en)
French (fr)
Inventor
Jean-Pierre Delahaye
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Telediffusion de France ets Public de Diffusion
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Telediffusion de France ets Public de Diffusion
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04H—BROADCAST COMMUNICATION
    • H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
    • H04H20/28—Arrangements for simultaneous broadcast of plural pieces of information
    • H04H20/33—Arrangements for simultaneous broadcast of plural pieces of information by plural channels
    • H04H20/34—Arrangements for simultaneous broadcast of plural pieces of information by plural channels using an out-of-band subcarrier signal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04H—BROADCAST COMMUNICATION
    • H04H60/00—Arrangements for broadcast applications with a direct linking to broadcast information or broadcast space-time; Broadcast-related systems
    • H04H60/09—Arrangements for device control with a direct linkage to broadcast information or to broadcast space-time; Arrangements for control of broadcast-related services
    • H04H60/14—Arrangements for conditional access to broadcast information or to broadcast-related services
    • H04H60/23—Arrangements for conditional access to broadcast information or to broadcast-related services using cryptography, e.g. encryption, authentication, key distribution
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04H—BROADCAST COMMUNICATION
    • H04H2201/00—Aspects of broadcast communication
    • H04H2201/10—Aspects of broadcast communication characterised by the type of broadcast system
    • H04H2201/13—Aspects of broadcast communication characterised by the type of broadcast system radio data system/radio broadcast data system [RDS/RBDS]

Definitions

  • the invention relates to a protocol for sending access control messages to RDS applications, to a corresponding sending device and to a receiving device.
  • the RDS system (for Radio Data System) is the data broadcasting system, as defined by the EBU, intended mainly for motorists who wish to listen to audio programs broadcast in frequency modulation.
  • EBU Radio Data System
  • this system has become a fully-fledged service delivery medium, with many motorists now enjoying the benefits and services distributed on this medium. However, these services are not limited to the latter.
  • RDS system offers a wide range of application possibilities such as communication of road messages, radio messaging, remote display or others.
  • Basic services such as program identification (PI), program chain name (PS), list of other frequencies (AF) on which the same program is broadcast, identification of programs for motorists (TP) and road announcements or program genre code (PTY), are provided by the aforementioned receivers.
  • RDS groups a succession of RDS data groups designated by RDS groups.
  • Each RDS group necessarily comprises four successive blocks of bits or bits, block A, block B, block C and block D, each block comprising 26 bits, 16 bits of RDS data and 10 bits of error correction code.
  • the subject of the present invention is a system for controlling access to RDS applications implemented using a protocol for transmitting access control messages to these applications, a transmitting device and a receiving device. such corresponding messages satisfying in all respects the constraints previously mentioned in the description.
  • the protocol for transmitting access control messages to applications on an RDS medium, object of the invention, in which the access control is carried out on the basis of access control messages distributed over at least one RDS group of four consecutive blocks of binary elements, is remarkable in that it consists, on transmission, for the RDS group considered, of transmitting in clear text on the first block of this RDS group a program identification message, to transmit in clear on the second block of the RDS group a coded message representative of the type of RDS group, relating to this RDS group, and a specific RDS application channel message, to be transmitted in at least partially encrypted form on the third and the fourth RDS block a plurality of RDS application messages respectively of access control messages.
  • the device for controlling access to applications on an RDS medium, object of the present invention in which the access control is carried out on the basis of access control messages distributed over at least one RDS group considered of four consecutive blocks of binary elements, each block comprising a field information and a parity check field, is remarkable in that it comprises, at the level of an FM transmitter equipped with an RDS coder, a clear coding module on the first block of the RDS group considered of a program identification message, a clear coding module on the second block of the RDS group considered of a coded message representative of the type of RDS group relating to the RDS group considered and an application channel message representative of at least one specific RDS application, a coding module in at least partially encrypted form on the third block of the RDS group considered of a plurality of RDS application messages respectively in clear of control of ac ces, a clear coding module on the fourth block of the RDS group considered of a plurality of messages, access control message, parity message, redundancy message, and, in encrypted form, RDS application messages
  • the device for controlling access to RDS applications to a user device in which access control is carried out on the basis of access control messages transmitted on at least one RDS group considered of four consecutive blocks of elements binary, each block comprising an information field and a parity control field, object of the present invention, is remarkable in that it comprises, at the level of an FM receiver equipped with an RDS decoder, a module for discrimination of the RDS group considered, a discrimination module in the consecutive blocks of the RDS group considered discriminated, access control messages and application messages encrypted, a module for decrypting encrypted RDS application messages making it possible to generate information from decrypted RDS applications, a conditional access control module for RDS applications decrypted on the basis of identity criteria for access control information and reference access control information. All of the modules are interconnected at the cutoff between the RDS decoder and the user device.
  • the protocol for transmitting access control messages to RDS applications and the corresponding access control device find application in the management of all types of RDS applications.
  • access control to RDS applications is carried out from access control messages distributed over at least one RDS group of four blocks. consecutive bits.
  • This protocol consists, on transmission, for the RDS group considered, of transmitting in clear on the first block of the RDS group a PI program identification message and of transmitting in clear on the second block, block B of the RDS group, a TG coded message representative of the relative RDS group to the RDS group considered and a VA application channel message representative of at least one specific RDS application, that for which the access control is performed.
  • the transmission protocol consists in transmitting, in at least partially encrypted form on the third C and the fourth D RDS block, a plurality of RDS application messages, these messages d RDS applications being transmitted in the form of at least partially encrypted, respectively of access control messages.
  • the access control messages are transmitted in clear.
  • FIG. 1 the structure of the blocks A, B, C, D is represented constituting the RDS group considered.
  • Each block includes a data or information field coded in 16 bits and a parity check field coded in 10 bits, the RDS group considered comprising a total of 104 bits.
  • the usual RDS service data messages and that the access control message in accordance with the object of the present invention are transmitted on the third and fourth blocks, blocks C and D , as shown in Figure 1, a parity message and a redundancy message being transmitted on the fourth block, block D.
  • the application channel message VA is intended to indicate to a suitable receiver the type code of group of scrambled data while the message consisting of the RDS data field or applications of the information field of the third block C, ie 16 bits plus the 7 bits of the access control message of block D in total 23 bits, are used to provide the access control system proper to the RDS application in question.
  • the above parity message or parity bit makes it possible to detect the odd residual errors.
  • the step of transmission in at least partially encrypted form of the third block of an RDS application message consists in modulating the data into encrypted and unencrypted data in packets with a determined number of consecutive bits.
  • a scrambling mask of the field block C information element is then used as shown in FIG. 1.
  • This scrambling mask can consist in preserving from scrambling the first four bits of the 16-bit information field of the third block C, these first four bits then always being encoded in clear.
  • the next twelve bits of the information field in block C are then reserved for RDS application data and can then be encrypted or unencrypted by modules of four bits, at discretion, depending on the application considered. In any case, the last four-bit module is always encrypted so as of course to ensure access control to the RDS application considered.
  • the encryption of RDS application messages can be carried out without limitation on transmission, using a 32-bit encryption suite.
  • the ciphering sequence is generated by means of a pseudo-random sequence generator receiving a clock signal and a generator polynomial, denoted P (x), as well as an initial loading word, noted I (x).
  • the encryption process for RDS application messages is performed over several basic periods. Each basic period is assigned a specific encryption key.
  • Each basic period is broken down in turn into several diversification periods for which the allocated encryption key is unchanged during these diversification periods.
  • the diversification is obtained by means of diversification parameters VD, V, the diversification parameter V taking into account the value of the RDS group considered.
  • the transmission scrambling cycle can be composed of one or more basic periods with which a specific encryption key is associated.
  • the low resource in transmission capacity of the RDS system as previously mentioned in the description does not allow to assign or make coexist several operators or several service providers for the same transmission channel. To this end, two classes of services are provided for the same operator or for the same service provider.
  • the scrambling parameters are known on reception, on the one hand, thanks to the access control messages transmitted in the protocol for transmitting the access control messages according to the subject of the present invention.
  • encryption data which, according to a particular aspect of the protocol for transmitting access control messages to RDS applications which is the subject of the present invention, can be stored on a tamper-proof storage medium as will be described in more detail in connection with a corresponding device.
  • the above-mentioned RDS applications and the corresponding access control messages advantageously use a particular type of group of all RDS groups.
  • the type of group used can be group 5A.
  • the access control messages have a common structure, these messages, coded in clear, being distributed over the blocks B, C and D of the RDS group considered.
  • the message relating to the application channel VA of the information field of the second block B is coded on 5 bits. It is thus understood that for a given application channel among the 2 5 application channels, there is, per RDS group considered, group 5A, a transmission potential of 32 bits corresponding to the information field of the third and fourth blocks, C and D, thus constituting a route of application considered.
  • Key image messages and synchronization messages support the signaling and information necessary for the management and proper functioning of the access control system itself.
  • a channel number message corresponding to the current channel number used for the transmission of encrypted RDS application messages, this message being referenced NV, is provided and coded in five bits, bits C 7 to C 11 .
  • An IS service identification message is coded on one bit, the C 6 bit, which makes it possible to switch access to a first or a second application denoted Service 1 or Service 2 depending on the value of the C 6 bit.
  • C / S message is coded on one bit, bit C 5 of the block C shown in Figure 2c.
  • bit C 5 the block C shown in Figure 2c.
  • the message transmitted is an image message of the keys whereas, on the contrary, for the value 1 of this same bit C 5 , the message transmitted is a synchronization or end of encryption message as will be described later in the description.
  • bits C 0 to C 4 of the block C are used in particular as a function of the value of the C / S message image of the keys or of synchronization as will be described later in the description.
  • the information field represented by bits D 0 to D 15 comprises 7 bits, D 9 to D 15 normally reserved for the transmission of encrypted application messages, a parity bit, the bit De, and eight bits of correcting code of errors, CRC, corresponding to bits D 0 to D 7 .
  • the error correcting code is of the FIRE type (35,27) as described previously in the description.
  • the protocol for transmitting access control messages for RDS application makes it possible to provide three classes of cryptographic services and a pseudo-random creation process with image of the encryption keys.
  • the signature is sent on a single channel specified by the key image messages.
  • the encrypted keys used are then transmitted.
  • the transmission of encrypted keys used for decryption on reception then uses a single channel specified by the control messages. access and must be accompanied by a signature.
  • the value of bits C 4 and C 3 is then given by table 3 below.
  • the signature then uses the same and same channel as the cryptogram of the encrypted keys emitted.
  • the encryption key index allows you to find the key to use to decrypt the received cryptogram.
  • the issued and received decrypted key is only validated when the cryptogram of the corresponding issued signature is correct.
  • the index of keys and cryptogram of the signature is different.
  • blocks A and B are always coded in clear, that is to say in the absence of encryption.
  • Block C can be partially or completely encrypted according to a multiple of groups of 4 bits from the least significant as described previously in the description. As to RDS D block, it is always encrypted.
  • the scrambling mask of block C makes it possible to modulate the range of the binary elements of the encryption suite, that is to say at least 20 bits and at most 32 bits.
  • blocks A, B, C, D are always in clear.
  • a message of index of the encryption key used, message of index of key IC, is then transmitted on 7 bits on block D, bits D 9 to D 15 . This message indicates the active key to apply when the synchronization messages are received.
  • bit C 5 represents the C / S message, key image message, this key image message being transmitted for the value equal to 0 of the aforementioned bit C 5 .
  • the scrambling mask message ME corresponds to bits C 3 and C 4 of block C.
  • Bit C 2 is a diversification message or flag.
  • the access control message consists of a synchronization or end of scrambling message.
  • Service channel messages when the message TM has the value 0, 31 bits without error code or 22 bits protected by an error correcting detector code and a parity bit are then available. Service channel messages are never encrypted or scrambled.
  • the encrypted message constituted by the cryptogram due to the limited transmission resources of the RDS system, must not exceed 256 bytes, that is to say 2048 bits.
  • each 64-bit portion of the encrypted cryptograms is transmitted via three RDS groups, which are advantageously transmitted under the conditions below described in connection with FIG. 3.
  • Each 64-bit portion or cryptograms encrypted according to the DES or RSA standard is subdivided, as shown in FIG. 3, into a first 21-bit section, a second 22-bit section and a third 21-bit section.
  • the aforementioned 64 bits constitute by definition the cryptogram or a portion of the transmitted cryptogram.
  • the protocol for transmitting access control messages to applications on an RDS medium which is the subject of the present invention, it is indicated that it is implemented, both at transmission that upon reception, from a tamper-resistant memory medium of the memory card type, a motherboard used for transmission containing 128 secret keys identified by a pointer, index of the IC key, when the DES standard is used .
  • the motherboard contains 128 public keys.
  • the daughter card contains the 128 secret keys pointed by the same key index IC, when the DES standard is used, and, on the contrary, 128 secret keys for the same modulo n when the RSA standard is used.
  • each channel can then successively transmit the first 21-bit segment, the second 22-bit segment and the last 21-bit segment of a cryptogram on three RDS groups, as shown diagrammatically in FIG. 3.
  • Transmission for each 64-bit cryptogram is thus carried out on three successive RDS groups or not, a first RDS group called synchronizing group allowing the transmission of the first section of 21 bits, a second RDS group said intermediate group allowing the transmission of the section, cryptogram, of 22 bits, and, finally , a last RDS group allowing the transmission of the last section, or cryptogram, of 21 bits.
  • the Boolean variable is complemented.
  • the first RDS group ensuring the transmission of a cryptogram, that is to say of the 21-bit section, is recognized as a synchronizing group.
  • the intermediate RDS group is protected by the FIRE error code (32,24) and the third and last RDS group is protected individually by the same error code, a parity bit from the last RDS group, the P2 bit on the FIG. 3, making it possible to check the consistency of all the data bits of the three RDS groups, synchronizing group, intermediate group and last RDS group, considered.
  • each group of 8 bits of CRC error correction code makes it possible to ensure the correction of the 24 bits to which each of these 8 error correction bits is associated, while the second parity bit P2 makes it possible to check the consistency of the 71 data bits of the three groups, that is to say of the corresponding bits transmitted by the synchronizing group, the intermediate group and the last group R DS, except for each of the 8 bits of error correction code CRC and of course of the second bit P2.
  • the access control messages include a field relating to the type of encryption system used, the TSC field with extended functionality, this field allowing reception, depending on the value assigned to it. attributed, a different interpretation of scrambled or encrypted messages.
  • the different values of this field allow at least the transmission and recognition, on reception, of an encrypted decryption key and of a signature, the encrypted key and the signature being coded on a same number N of bits distributed over G RDS groups.
  • the encrypted decryption key is coded on 64 bits and is necessarily accompanied by a signature of the same size.
  • the value of the field relating to the type of encryption system used TSC is then in binary value equal to 11.
  • the key and signature pair requires the use of six RDS groups.
  • the protocol, object of the present invention allows either the transmission of unsigned encrypted messages or the transmission of signed encrypted messages.
  • the size of the encrypted messages is fixed. It is for example 2048 bits, or 32 elementary encrypted messages or cryptograms.
  • the application channel VA serves as a continuity index in order to ensure the transmission and recognition of the corresponding encrypted message elements.
  • the value of the field relating to the type of encryption system used TSC in the key image message is then 00 in binary and the parameters relating to the successive encrypted elementary messages have the values given in table 5 below:
  • transmission that is to say of the transmission and recognition on reception of encrypted signed messages
  • these can advantageously have a variable size between a minimum number m, m being able for example be taken equal to 2, and a maximum number M of elementary encrypted messages or successive cryptograms with which a signature is associated.
  • M can be taken equal to 32.
  • the transmission of the signature indicates to the receiver, on the one hand, the end of transmission of the elementary messages or cryptograms, and, on the other hand, the signature of the encrypted message transmitted.
  • the field relating to the application channel VA serves as a continuity index for the succession of the above-mentioned encrypted elementary messages. Relative field values the type of encryption system used TSC key image messages are then in binary 00 for the cryptograms, or elementary encrypted messages, and 10 for the signature, the values of the parameters being given in table 6 below:
  • each successive elementary message, or cryptogram is associated with a continuity tracking index, the discrimination between encrypted signed message and signature being obtained for the two distinct values 00 and 01 of the TSC field relating to the type of the encryption used.
  • the protocol which is the subject of the present invention also allows the transmission and recognition of encrypted messages with an encrypting suite configured by encryption keys varying in time, these encrypted messages corresponding to RDS application messages.
  • the binary value of the field relating to the type of encryption system used TSC is for example 01.
  • the 32-bit encryption suite is used to scramble an RDS application group, the scrambling process consisting of modulo 2 arithmetic between the bits of data conveyed by the RDS group, for the application under consideration, and the encryption suite.
  • a modular mask makes it possible to have a clear portion of the quads of block C.
  • image messages of encryption keys can also be signed.
  • a condensed signature is obtained from a secret key buried on an inviolable support as described previously in the description, the condensed signature being calculated on a number P of bits from a pseudo-random sequence and calendar date information for example.
  • the condensed signature is transmitted by means of a plurality of the synchronization messages previously mentioned in the description.
  • the condensed signature can be calculated on 64 bits.
  • the date code, modified Julian date, of the RDS 4A group is part of the data of the message to be signed.
  • Synchronization messages contain the condensed signature transmitted in a 12-bit format for example.
  • the synchronization messages include a time validation field VT of the encryption keys transmitted, immediate or deferred validation, depending on the value of this field, being carried out on reception.
  • the synchronization message contains the condensed signature.
  • the first elementary encrypted message then comprises a header and input parameters, and the second elementary encrypted message comprises a specific elementary encrypted message such as a tamper-evident medium identification code.
  • the access control messages are distributed over at least one RDS group considered of four consecutive blocks of binary elements.
  • the device comprises, at the level of an FM transmitter equipped with an RDS coder, the RDS coder bearing the reference B and being interconnected with a stereo coder C, which makes it possible to control the FM transmitter D for broadcasting the corresponding RDS service, and the RDS coder comprising a modem A, which is connected by a switched PSTN telephone link to a modem 10, a clear coding resource 1 1 on the first block of the RDS group considered of a program identification message, resource 1 2 of plain coding on the second block of the RDS group considered an encrypted message representative of the type of RDS group on the RDS group considered, and a channel message representative implementation of at least one RDS specific application, a resource 1 3 as encoding at least partly encrypted over the third block of the RDS group considered, a plurality of application messages RDS respectively clear access control, as well as a clear coding resource 1 4 on the fourth block of the RDS group considered of a plurality of messages, access control message, parity messages, redundancy message, and,
  • the aforementioned coding resources 1 1 , 1 2 , 1 3 , 1 4 , on the first, second, third and fourth blocks of the RDS group in question are interconnected, on the one hand, to the RDS B encoder by means of the modem 10, of the connection of the switched telephone network PSTN and modem A, and, on the other hand, to a GPS reference station, denoted G 1 , delivering reference GPS positioning data at the transmission level.
  • the coding resources 1 1 , 1 2 , 1 3 , 1 4 of the messages on the first, second, third and fourth blocks of the RDS group considered are advantageously constituted by a microcomputer provided with its peripheral organs, this microcomputer being able, of course, to include a working memory M t and a program memory M P in which are installed message coding program modules on the first, second, third and fourth blocks of the RDS group considered, as shown in FIG. 1.
  • the peripheral members comprise at least one microprocessor card reader device, bearing the reference 1 5 , the microprocessor card itself, designated by motherboard , bearing the reference 1 6 .
  • the whole of the microprocessor card reader and microprocessor card device makes it possible to ensure the coding in encrypted form of the messages coded on the third and the fourth block of the RDS group considered.
  • the card reader 1 5 can consist of a card reader of the TLP224 type for example, marketed by the company BULL CP8 78430 Louveciennes, France, this card reader can be integrated directly into the microcomputer, the microcomputer being connected to the RDS coder as mentioned previously.
  • the coding program modules of messages include, for example, an encryption module to generate a 32-bit encryption suite. This encryption sequence can then be transmitted via four consecutive RDS blocks or an RDS group, as described previously in the description.
  • the encryption module comprises a pseudo-random generator module of digits parameterized by a generator polynomial P (x) and by an initial loading word, noted I (x).
  • the encryption information stored on the microprocessor card, motherboard bearing the reference 1 6 in FIG. 4 includes at least information relating to the number of encryption keys to be used, to the reference of at least one specific encryption, the basic period of validity of each encryption key, the duration of an encryption diversification period for the encryption key considered, the number of diversification periods generated for the encryption key during the duration of validity base as well as a plurality of reference initial loading words I (x) and a plurality of reference generating polynomials P (x).
  • the aforementioned motherboard 1 6 actually contains all the dynamic and static parameters of the access control messages.
  • the dynamic parameters concern the scrambling cycle, the number of keys, the duration of the basic periods and of the diversification periods. Fixed parameters are long-lasting options linked to the life cycle of the corresponding current motherboard.
  • Table 9 below gives the organization of the transmission motherboard bearing the reference 1 6 in FIG. 4.
  • Period of validity of a DC key It is the time duration of a key or basic period Duration of SD diversification period It is the duration of the diversification period within a diversification period Number of MIC key image messages It is the number of key image messages within a diversification period Number of MS synchronization messages It is the number of synchronization messages within a diversification period
  • this device at an FM receiver equipped with an RDS decoder as shown in Figure 5 includes, in addition to the RDS decoder 2 0 receiving the radio reception of the transmitter D, a resource denoted 2 1 of discrimination of the RDS group considered, a resource noted 2 2 of discrimination in the consecutive blocks of the group considered discriminated from the access control messages and encrypted RDS application messages, a resource 2 3 for decrypting the encrypted RDS application messages used to generate decrypted RDS application information, as well as a resource denoted 2 4 for conditional access control to the decrypted RDS applications on identity criterion for access control information and reference access control information. All of the aforementioned resources 2 1 to 2 4 are interconnected in cutoff between the RDS decoder 2 0 and the user device, which is represented in FIG. 5 by a local GPS receiver bearing
  • encrypted RDS application and access messages, the decryption resource 2 3 and the conditional access control resource 2 4 to RDS applications are advantageously constituted by a microcomputer provided with its peripheral organs.
  • This microcomputer includes a working memory M ' t and a program memory M' P in which are installed modules of discrimination programs of the RDS group considered, discriminating in the consecutive blocks of the RDS group considered discriminating access control messages and encrypted RDS application messages, a program decryption module for encrypted RDS application messages making it possible to generate information of decrypted RDS applications and a conditional access control module to RDS applications on criteria of identity of the access control information and reference access control information.
  • peripheral members bear the reference 2 5 and 2 6 and may advantageously comprise a microprocessor card reader device, the card reader device bearing the reference 2 5 and the microprocessor card designated by daughter card bearing reference 2 6 .
  • peripheral members 2 5 and 2 6 are intended to provide decryption information stored in the daughter card 2 6 to ensure the decoding of access control messages and RDS application messages encrypted in the form of information, messages decrypted RDS application.
  • the microcomputer 2 1 , 2 2 , 2 3 , 2 4 is interconnected in a so-called cut-off mode between the decoder 2 0 RDS and the device for use or GPS receiver G 2 .
  • the cut-off connection mode makes it possible to ensure access or absence of access to the GPS G 2 receiver on the validation criterion respectively of non-validation of this access by the process and the access control system.
  • the decryption module 2 3 comprises, like the encryption module previously described in connection with FIG. 4 and with FIG. 2a, a pseudo-random generator generator of digits parameterized by a generator polynomial and by an initial loading word P (x) respectively I (x).
  • the decryption information stored on the daughter card 2 6 include at least subscriber class carrier code, allocated usage time credit, RDS service identification information of a plurality of reference IPL words, a plurality of reference generator polynomials and parameters associated with an authentication algorithm making it possible to generate a personalized authentication value.
  • the control resource at the receiving device searches for the new decryption parameters. If the validity of the subscriber's rights has expired or if the current date is outside the validity range, or if the term credit has been used up, the order resource proceeds to deactivate the daughter card and disarm the decryption indicator. The reception of a valid encryption key or the change of key declared as a new valid key makes it possible to arm or maintain the decryption indicator on receipt of validated synchronization messages.
  • the daughter card verification test can be performed in the background task activated periodically.
  • Table 10 represents the strategy used for synchronization and end scrambling messages, the aforementioned strategy being given as non-limiting example.
  • a 64-bit format is provided in the memory zone dedicated for this purpose in the daughter card 2 6 .
  • the reception access control device as shown in FIG. 5 verifies the period of validity of the rights subscribed by the subscriber correspondent, start date and end date, when the latter has subscribed for periods of validity.
  • the credit in duration is accompanied by a notion of allocated time, flexible according to a plurality of parameters such as type of service, added value of content.
  • the organization of the daughter card memory plane 2 6 is given below in Table 11.
  • an authentication operation of the card daughter June 2 may be provided, such an operation is obtained by the use of a cryptographic algorithm owner.
  • the aforementioned cryptographic algorithm can for example be the "Telepass" algorithm of the creator of corresponding microprocessor cards.
  • IPL word can be diversified otherwise.
  • the flag and type of diversification are in the keyframe messages and the synchronization messages contain the diversification value.
  • the daughter card authentication procedure which is costly in time, can preferably be carried out at the start, when the daughter card is inserted into the card reader 2 5 . Taking into account the change of keys and the entry into service of the corresponding keys are guaranteed as long as the daughter card is present and the validity of the subscription is in conformity.
  • the GPS differential corrective data application and the access control system share 60% of the RDS transmission resource, i.e. 7 to 8 RDS groups per second.
  • the DPS G 1 reference station supplies the abovementioned microcomputer PC encoder with the differential corrective data GPS, dGPS, the PC encoder microcomputer 1 1 , 1 2 , 1 3 , 1 4 enabling the RDS format to be these data in order to ensure their transmission via modem 10 and modem A to the RDS coder B and to the transmitter D for transmission.
  • the RDS decoder circuit 2 0 can be tuned to the transmission frequency in band 2 of the transmitter D.
  • the RDS groups 6A received are transmitted to the decoder microcomputer 2 1 , 2 2 , 2 3 , 2 4 , which allows the RTCM format to be reconstituted for the GPS receiver G 2 .
  • the accuracy of the position data is then improved thanks to the contributions of the corrective dGPS data received via the RDS support, that is to say the FM network.

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EP96401198A 1995-06-07 1996-06-05 Nachrichtenübertragungsprotokoll für Zugangskontrolle für RDS-Anwendung, bzw. Übertragungs- und Empfangsvorrichtung dafür Withdrawn EP0748073A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9506704 1995-06-07
FR9506704A FR2735311B1 (fr) 1995-06-07 1995-06-07 Protocole d'emission de messages de controle d'acces a des applications rds, dispositifs d'emission et de reception correspondants.

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EP0748073A1 true EP0748073A1 (de) 1996-12-11

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EP96401198A Withdrawn EP0748073A1 (de) 1995-06-07 1996-06-05 Nachrichtenübertragungsprotokoll für Zugangskontrolle für RDS-Anwendung, bzw. Übertragungs- und Empfangsvorrichtung dafür

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EP (1) EP0748073A1 (de)
FR (1) FR2735311B1 (de)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2738434A1 (fr) * 1995-08-28 1997-03-07 Sanyo Electric Co Recepteur de signaux numeriques capable de recevoir des donnees d'emission chiffrees en traitement en ligne
EP0808041A2 (de) * 1996-05-13 1997-11-19 SANYO ELECTRIC Co., Ltd. Datenverarbeitungsschaltung für die Verschlüsselung oder Entschlüsselung von Zusatzdaten eines Rundfunkprogramms
WO1998054855A1 (en) * 1997-05-30 1998-12-03 Scientific-Atlanta, Inc. Encoding/decoding scheme for communication of low latency data for the subcarrier traffic information channel
WO1999011042A1 (en) * 1997-08-23 1999-03-04 Koninklijke Philips Electronics N.V. Wireless network
GB2415860A (en) * 2004-06-30 2006-01-04 Nokia Corp A method of providing a broadcast radio service to a remote terminal
WO2009067567A2 (en) * 2007-11-21 2009-05-28 Qualcomm Incorporated Method and system for transmitting radio data system (rds) data
US8478216B2 (en) 2007-11-21 2013-07-02 Qualcomm Incorporated Method and apparatus for searching for or tuning to one or more radio stations with minimum interaction with host processor
US8503957B2 (en) 2007-11-21 2013-08-06 Qualcomm Incorporated Radio data system (RDS) data processing methods and apparatus
US8666304B2 (en) 2007-11-21 2014-03-04 Qualcomm Incorporated Methods and apparatus for downloading one or more radio data system (RDS) group type processing routines for RDS data

Citations (4)

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GB2208457A (en) * 1987-08-01 1989-03-30 Pioneer Electronic Corp Radio data system protocol discrimination
EP0461436A1 (de) * 1990-06-13 1991-12-18 Robert Bosch Gmbh Verfahren zur selektiven Rufübertragung und Rufempfänger zur Durchführung des Verfahrens
DE4024132A1 (de) * 1990-07-30 1992-02-13 Blaupunkt Werke Gmbh Empfaenger fuer im radiodatensystem uebertragene daten
EP0495136A2 (de) * 1991-01-15 1992-07-22 Pioneer Electronic Corporation Datenübertragungsverfahren bei RDS-Rundfunk

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2208457A (en) * 1987-08-01 1989-03-30 Pioneer Electronic Corp Radio data system protocol discrimination
EP0461436A1 (de) * 1990-06-13 1991-12-18 Robert Bosch Gmbh Verfahren zur selektiven Rufübertragung und Rufempfänger zur Durchführung des Verfahrens
DE4024132A1 (de) * 1990-07-30 1992-02-13 Blaupunkt Werke Gmbh Empfaenger fuer im radiodatensystem uebertragene daten
EP0495136A2 (de) * 1991-01-15 1992-07-22 Pioneer Electronic Corporation Datenübertragungsverfahren bei RDS-Rundfunk

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2738434A1 (fr) * 1995-08-28 1997-03-07 Sanyo Electric Co Recepteur de signaux numeriques capable de recevoir des donnees d'emission chiffrees en traitement en ligne
EP0808041A2 (de) * 1996-05-13 1997-11-19 SANYO ELECTRIC Co., Ltd. Datenverarbeitungsschaltung für die Verschlüsselung oder Entschlüsselung von Zusatzdaten eines Rundfunkprogramms
EP0808041A3 (de) * 1996-05-13 1999-04-21 SANYO ELECTRIC Co., Ltd. Datenverarbeitungsschaltung für die Verschlüsselung oder Entschlüsselung von Zusatzdaten eines Rundfunkprogramms
US6128390A (en) * 1996-05-13 2000-10-03 Sanyo Electric Co., Ltd. Data processor for FM multiplex broadcast
WO1998054855A1 (en) * 1997-05-30 1998-12-03 Scientific-Atlanta, Inc. Encoding/decoding scheme for communication of low latency data for the subcarrier traffic information channel
WO1999011042A1 (en) * 1997-08-23 1999-03-04 Koninklijke Philips Electronics N.V. Wireless network
US6178512B1 (en) 1997-08-23 2001-01-23 U.S. Philips Corporation Wireless network
GB2415860B (en) * 2004-06-30 2007-04-18 Nokia Corp A method of providing a radio service at a remote terminal
GB2415860A (en) * 2004-06-30 2006-01-04 Nokia Corp A method of providing a broadcast radio service to a remote terminal
WO2009067567A2 (en) * 2007-11-21 2009-05-28 Qualcomm Incorporated Method and system for transmitting radio data system (rds) data
WO2009067567A3 (en) * 2007-11-21 2009-10-22 Qualcomm Incorporated Method and system for transmitting radio data system (rds) data
US8326216B2 (en) 2007-11-21 2012-12-04 Qualcomm Incorporated Method and system for transmitting radio data system (RDS) data
CN101868930B (zh) * 2007-11-21 2013-06-12 高通股份有限公司 用于发射无线电数据系统(rds)数据的方法及系统
US8478216B2 (en) 2007-11-21 2013-07-02 Qualcomm Incorporated Method and apparatus for searching for or tuning to one or more radio stations with minimum interaction with host processor
US8503957B2 (en) 2007-11-21 2013-08-06 Qualcomm Incorporated Radio data system (RDS) data processing methods and apparatus
US8666304B2 (en) 2007-11-21 2014-03-04 Qualcomm Incorporated Methods and apparatus for downloading one or more radio data system (RDS) group type processing routines for RDS data

Also Published As

Publication number Publication date
FR2735311B1 (fr) 1997-08-14
FR2735311A1 (fr) 1996-12-13

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