Title of Invention

A SYSTEM FOR TRANSMITTING THE SCRAMBLED BROADCAST- SIGNALS IN SINGLE FREQUENCY NETWORK AND A METHOD THEREOF

Abstract Disclosed is a system for transmitting encrypted broadcast signals to different transmitters on a single frequency network (SFN) in a digital broadcasting system. The system for transmitting encrypted broadcast signals on the SFN includes: a main broadcasting system for transmitting encrypted broadcast signals including data streams and transmitter identification information (TII) through a main broadcasting network; a repeating system for amplifying encrypted broadcast signals of the main broadcasting network and transmitting the amplified broadcast signals, or modulating and amplifying streams input by the main broadcasting system through a private line and repeating broadcast signals of the main broadcasting system through a repeating network; and a decrypting key provider for receiving a decrypting key value from the main broadcasting or repeating system and transmitting a user authentication and decrypting key to a charged subscriber terminal through a mobile communication network.
Full Text FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)
"A SYSTEM FOR TRANSMITTING THE
SCRAMBLED BROADCAST-SIGNALS IN
SINGLE FREQUENCY NETWORK AND A
METHOD THEREOF"
(1) KTFREETEL CO., LTD, a Korean company, of7-18,sincheon-dong,songpa-gu,Seoul 138, Korea, and
(2) ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE, a Korean Institute, of 161, Gajeong-dong, Yuseong-gu, Daejeon 305-350, Korea
The following specification particularly describes the invention and the
manner in which it is to be performed.

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[DESCRIPTION]
[Invention Title]
A SYSTEM FOR TRANSMITTING THE SCRAMBLED BROADCAST-
SIGNALS IN SINGLE FREQUENCY NETWORK, AND A METHOD
THEREOF
[Technical Field]
The present invention relates to a system and method for transmitting encrypted broadcast signals on a single frequency network. More specifically, the present invention relates to a system and method for transmitting encrypted broadcast signals to respective transmission units in a digital broadcast system when the transmission units are different on the single frequency network.
[Background Art]
Digital broadcasting has the characteristics of multiple channels, high quality, and multiple functions. In particular, digital broadcasting allows concurrent transmission of combined images, voice, and data irrespective of their contents and size because of the development of multiplexing capabilities, and also allows interactive services by using a return channel
based on a modem. Accordingly, digital data broadcasting overcomes the
limits of existing analog broadcasting and provides multimedia services with higher added values to viewers.
In general terrestrial and satellite digital broadcasting, a transmitter

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for forming a main broadcasting network is provided in a single frequency network (SFN), a shade region in which no service is available is generated in the SFN, and a gap filler for servicing the shade region is provided to eliminate the shade region of the main broadcasting network. For example,
in a satellite digital multimedia broadcasting (DMB) system, most regions
are available for receiving signals from a satellite, and the gap filler is used to acquire a receiving region in the shade regions in which no direct signal receiving is allowed, such as regions given in a subway, a tunnel, and a building.
In detail, when it is not easy to directly receive satellite signals on
the ground side, that is, within the tunnel, underground, and building, the gap filler receives the satellite signals through a satellite signal receive antenna and starts broadcasting.
Main broadcasting stations represent broadcasting stations that
function as a main center of the broadcasting network system, and they plan, produce, and transmit broadcasting programs. In Korea, radio broadcasting stations include KBS, MBC, CBS, BBS, PBS, SBS, and Keukdong Broadcasting, and television broadcasting includes KBS, MBC, and SBS. The broadcasting stations located in Seoul are established to be
their transmitters. Commercial broadcasting in the USA or Japan form the
broadcasting networks through contracts, but Korean broadcasting systems have a single organization such as KBS or have the same capital system such as MBC and CBS, and hence the transmitters perform a strong role in the system and management in addition to broadcasting, substantially as
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headquarters.
Also, a repeater station is an auxiliary station with less power, and
is also called a satellite station. Conventionally, a broadcasting station has a service region, that is, a designated broadcasting region, but since boundary regions have weak radio wave arrival and blanket areas, the satellite station is installed for the boundary regions. It is installed at mountaintops for receiving radio waves from the transmitters, and it receives the waves through high-sensitivity receivers, electrically amplifies them, and broadcasts them as radio waves of different frequencies.
However, when a main broadcasting network service provider is
different from a repeater service provider, the repeater service provider generates the cost of installing and maintaining a broadcasting network in the shade region, and the repeater service provider charges for the usage of the repeating network. That is, the repeater service must be a charged
service for the purpose of activating the repeating network, but no
appropriate treatment for the charged service has been provided up to now.
[Disclosure]
[Technical Problem]
It is an advantage of the present invention to provide a system and
method for transmitting encrypted broadcast signals on a single frequency
network for activating a repeating network through a charged repeater
service and allowing the main broadcasting network service provider to
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extend the broadcasting network by providing a charged repeater service from a repeater service provider in a terrestrial and satellite digital broadcasting system.
It is another advantage of the present invention to provide a system
and method for transmitting encrypted broadcast signals on a single
frequency network for controlling charged subscribers and uncharged subscribers to receive a service within a coverage of the main broadcasting network, controlling the uncharged subscribers to receive the service within a superimposed region of the main broadcasting network and the repeating
network, and controlling the charged subscribers to receive the service
within the coverage region of the repeating network in the broadcasting network with a single frequency network.
[Technical Solution]
In one aspect of the present invention, in a system for transmitting
broadcast signals on a single frequency network (SFN) for terrestrial and satellite digital broadcasting, a system for transmitting encrypted broadcast signals on the SFN includes: a main broadcasting system for transmitting encrypted broadcast signals including data streams and transmitter
identification information (Tll) through a main broadcasting network; a
repeating system for amplifying encrypted broadcast signals of the main broadcasting network and transmitting the amplified broadcast signals, or modulating and amplifying streams input by the main broadcasting system
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through a private line and repeating broadcast signals of the main
broadcasting system through a repeating network; and a decrypting key
provider for receiving a decrypting key value from the main broadcasting or
repeating system and transmitting a user authentication and decrypting key
to a charged subscriber terminal through a mobile communication network.
In another aspect of the present invention, in a method for transmitting broadcast signals on a single frequency network (SFN) for terrestrial and satellite digital broadcasting, a method for transmitting encrypted broadcast signals on the SFN includes: a) a system multiplexer
of a main broadcasting station multiplexing service multiplexing data into
broadcast signals; b)encrypting the broadcast signals and generating a encrypting key; c) inserting transmitter identification information (Tll) to the encrypted broadcast signals so that a subscriber terminal may determine whether the encrypted broadcast signals are transmitted through a main
broadcasting network or a repeating network; d) transmitting the encrypted
broadcast signals to an uncharged or charged subscriber through the main broadcasting network; and e) providing a decrypting key of the encrypted broadcast signals to a mobile communication system through a mobile communication network or a private line.

[Description of Drawings]
FIG. 1 shows a schematic diagram of a system for transmitting encrypted broadcast signals in a single frequency network according to an
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embodiment of the present invention.
FIG. 2 shows a schematic diagram for a service for transmitting encrypted broadcast signals in a single frequency network according to an embodiment of the present invention.
FIG. 3 shows conditional access service availability for subscriber
types and receiving locations according to an embodiment of the present invention.
FIG. 4 shows a block diagram for encrypted transmission and receiving in a system for transmitting encrypted broadcast signals on a single frequency network according to an embodiment of the present invention.
FIG. 5 shows an operational flowchart of a method for transmitting encrypted broadcast signals on a single frequency network according to an embodiment of the present invention.

[BEST MODE]
In the following detailed description, only the preferred embodiment
of the invention has been shown and described, simply by way of illustration
of the best mode contemplated by the inventor(s) of carrying out the
invention. As will be realized, the invention is capable of modification in
various obvious respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not restrictive. To clarify the present invention, parts that are
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not described in the specification are omitted, and parts for which similar descriptions are provided have the same reference numerals.
In the embodiment of the present invention, data streams to be
transmitted to a subscriber are encrypted so that a transmitter identifier may
be used as a value for finding a key of the transmitted data streams and a
receiving process may be controlled for the respective transmitters. In other words, a system and method for controlling a receiver to restrict access to each transmitter according to transmission units when the transmission units are different on a single frequency network in a terrestrial and satellite
digital broadcasting system will be disclosed in the embodiment of the
present invention.
In detail, charged subscribers and uncharged subscribers can receive a service within a coverage area of the main broadcasting network, and the charged subscribers can receive the service within the coverage
area of the repeating network. Also, the uncharged subscribers and
charged subscribers can concurrently receive the service within a superimposed coverage area of the main broadcasting network and the repeating network in the broadcasting network with a single frequency network. In this instance, it is needed as prerequisites that the service of
the main broadcasting networks for uncharged subscribers may not be
influenced by an addition of repeating networks, the service coverage of the main broadcasting networks may not be reduced, and service consecution is to be acquired when a handoff occurs between the main broadcasting network and the repeating network.
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In the embodiment of the present invention, the network identification and the terminals' charged/uncharged subscription states are distinguished. The network identification function (NIF) uses the transmitter identification information (Tll) of the terrestrial DMB standard (ETS 300.401
of Eureka-147 Rule) to assign identifiers to the broadcasting network and
the repeating network, and efficiently manages the networks according to distinguished signals. Therefore, fundamental access interception and security are achieved on the data level by encrypting part of transmission data by using a Tll-based key.
In this instance, the encrypting process is performed so as to
prevent the terminal that has no NIF from being used on all the networks without network identification in advance, and in this instance, the encrypting process is not only applied to the repeating network because the signals work as interference in the signal-superimposed area differing from
the signals of the main broadcasting network when the encrypting process
is applied to the repeating network.
FIG. 1 shows a schematic diagram of a system for transmitting encrypted broadcast signals in a single frequency network according to an embodiment of the present invention.
Referring to FIG. 1, the system for transmitting encrypted broadcast
signals in a single frequency network includes a main broadcasting system 110 for transmitting the transmitter identification information (Tll), a mobile communication system 130 for authenticating a user and transmitting a key value for allowing a conditional access through a mobile communication
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network, a repeater system 120 for repeating streams of the main
broadcasting station, and a subscriber terminal 140 for processing the
repeated streams. Hereinafter, the main broadcasting system 110 will be
correspondingly used as a main broadcasting station and the repeater
system 120 will be correspondingly used as a repeater station.
First, the system for transmitting encrypted broadcast signals in a single frequency network adds an encryptor and an encrypting key generator to the main broadcasting station so that multimedia contents are encrypted by using Tll and conditional access, and the main broadcasting
station 110 adds an encryptor 115 to the existing broadcasting system to
thus scramble multimedia programs or contents, generate an encrypting key, and apply Tll so that a subscriber terminal may identify that the encrypted broadcasting signals are transmitted through the main broadcasting network.
Also, in the embodiment of the present invention, in the case of the
single frequency network (SFN), data for the main broadcasting network and the repeating network are configured to have the same streams and guarantee signal synchronization so that the broadcasting networks are formed without interference between the main broadcasting network and
the repeating network.
In this instance, the Tll is used as information for identifying the transmitter, and is used for transmitter identification and a decrypting key, and the Tll substantially controls the subscriber terminal to determine whether the broadcasting signals are transmitted through the main
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broadcasting network or the repeating network. In this instance, in the case
of the above-noted Tll, no interference of the SFN occurs when pieces of
the Tll are different. The Tll does not provided in the data area and is
established by the combinations of subcarriers of an OFDM sync channel,
the combinations are arranged to be not repeated, and hence the IDs of the
received transmitters can be distinguished when at least two signals are received in the SFN.
The main broadcasting station 110 establishes Tll of the main broadcasting station and applies the Tll so as to protect a corresponding
encrypting key, and periodically modifies the Tll of the main broadcasting
station 110 and applies the modified Tll when performing corresponding encrypting.
Further, the main broadcasting station generates an encrypting key for encrypting an encrypting algorithm and data to which an encrypting key
generation algorithm is applied and which are then transmitted, and
scrambles transmission data according to the corresponding encrypting key, and the subscriber terminal 140 finds a decrypting key corresponding to the received Tll and decrypts the data.
Also, the repeater station 120 amplifies frequency network signals
corresponding to the SFN and transmits the amplified signals, or modulates
streams input by the main broadcasting station 110 through private lines, amplifies the modulated signals, and transmits the amplified signals. Also, when repeating the streams input by the main broadcasting station 110, the repeater station 120 re-allocates a repeater station Tll value to be different
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from the main broadcasting station Tll value according to an encrypted
function, and transmits it.
For example, a repeating network server (not illustrated) of the
repeater station 120 gathers transmission signals of six service providers to
generate Tll, modulates it based on the TDM scheme, and outputs
modulated results to a satellite terrestrial station for the purpose of
repeating broadcast programs.
Also, the repeater station 120 generates a key used for encrypting,
and transmits the key to the main broadcasting station or the repeater
station or transmits the same through a mobile communication network, and
in this instance, distinguishes charged subscribers and manages
subscribers. That is, the repeater station 120 generates repeater station Tll
and a decrypting key (CDMA_Key) so as to manage and control the
repeating network center, manages three keys (main broadcasting station
Tll, repeater Tll, and a decrypting key) in an integrated manner, and
periodically updates the keys.
Further, the mobile communication system 130 transmits the
decrypting key value to the terminal 140 of a charged subscriber through
the mobile communication network.
In addition, the subscriber terminal 140 decrypts the encrypted
signals of the main broadcasting network included in the broadcasting
signals received through the main broadcasting network or the repeating
network, the Tll, and the encrypting key according to a predefined
decrypting scheme.
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In further detail, referring again to FIG. 1, the main broadcasting
station 110 includes a media encoder 111, a plurality of data servers 112a
to 112n, a service multiplexer 113, a system multiplexer 114, a encryptor
115, a encrypting key generator 116, a main broadcasting station Tll
inserter 117, a modulator 118, and an HPA/transmitter 119. In this instance,
the Tll is a proper identifier assigned to the transmitter, the Tll signal is transmitted through a synchronous channel, and the Tll can be used together with frequency information (Fl) in the SFN.
The service multiplexer 113 multiplexes pieces of additional
information related to audio, data, and video data respectively provided by
the contents provider's media encoder 111 or the data servers 112a to 112n. The audio service is transmitted through an independent channel so as to provide a CD-quality audio service. The data service can be used to transmit text data such as lyrics of the audio service. Since the video
service must include moving pictures, audio, and multiplexing/synchronizing
information, the video service is transmitted after it is multiplexed into a stream through a video multiplexer. In this instance, the audio, the data, and the video service are multiplexed into a service channel by a service multiplexer, it is combined with transmission data to be a frame by a system
multiplexer, and it is then transmitted through a physical channel, in this
Instance, the conditional access function is not performed by the video multiplexer, encrypting is performed by the encryptor, and decrypting is performed through a main broadcasting station Tll.
The system multiplexer 114 multiplexes the data that is
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multiplexed by the service multiplexer 113 into broadcast signals in a transmission frame format.
The encryptor 115 scrambles the broadcast signals transmitted
by the system multiplexer 114, and in this instance, the main broadcasting
station Tll inserter 117 inserts Tll into the broadcast signals. That is, the
main broadcasting station scrambles multimedia programs or contents, transmits a decrypting key for decrypting the broadcast signals according to a predetermined encrypting scheme, and inserts Tll for determining whether the network having transmitted the broadcast signals is a main broadcasting
station or a repeater station, That is, the main broadcasting station and the
repeater station transmit Tll for determining by the subscriber station whether the transmitted broadcast signals are main broadcasting station signals or repeater station signals.
The modulator 118 modulates the encrypted broadcast signals
and the inserted main broadcasting station Tll, and the HPA/transmitter 119
transmits the modulated broadcast signals to the subscriber through the main broadcasting network. In this instance, the high power amplifier (HPA) represents a high power amplifier with good linearity from among power amplifiers (PAs), and it receives signals from a frequency upconverter and
amplifies the signals so as to generate defined radio frequency outputs to
the transmitter's final output terminal.
Further, the repeater station 120 may include an on-channel repeater 121 and a repeater station Tll inserter 122, and in this instance, the repeater station 120 amplifies and transmits signals of the main
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broadcasting network corresponding to the SFN, or modulates, amplifies,
and repeats the stream input by the main broadcasting station through the
private line. In the case of repeating the stream, the Tll value of the
repeater station is re-allocated to be different from the value of the main
broadcasting station so that it is disallowed for the uncharged subscribers to
receive signals within the coverage of the repeating network.
Also, the repeater station 120 receives an ensemble transport interface (ETI) signal of the main broadcasting station 110, transmits the ETI signal to an energy distribution encryptor, a convolutional encoder, and
a time interleaver to multiplex the signal into a TDM signal, and transmits
the result signal for the purpose of satellite transmission. In this instance, a Tll value to be used on the repeating network by using a specific field of the TDM signal is inserted into the repeater station 120.
That is, the repeater station 120 receives the TDM signal from the
satellite and demodulates it into an OFDM signal, and in this instance, it
extracts the Tll value included in the TDM signal and inserts the Tll value into the on channel of the OFDM signal. In this instance, since the Tll value to be used for the repeating network is different from the Tll value used by the main broadcasting network, the Tll value of the repeating network is
selected and inserted into the TDM field so that the keys to be decrypted by
the receiver may have the same value.
Further, the mobile communication system 130 includes a user authentication server 131, and functions as a decrypting key provider for transmitting a decrypting key for decrypting the encrypted broadcast signals
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to a charged subscriber's terminal. Also, the mobile communication system
130 periodically transmits the decrypting key through the mobile
communication network or the Internet so that the subscriber terminal may
decrypt the received key and may extract the corresponding encrypting key.
Also, the charged subscriber terminal receives the decrypting key
from an encrypting server through the mobile communication system to decrypt the conditionally accessed broadcast signals, and thereby receives a charged service from the repeating network.
FIG. 2 shows a schematic diagram of a conditional access
service depending on a transmitter on the single frequency network (SFN)
according to an embodiment of the present invention.
Referring to FIG. 2, the conditional access service area
depending on a transmitter on the SFN includes a main broadcasting
network 210, a repeating network 220, and a superimposed area 230 of the
main broadcasting network coverage and the repeating network coverage.
The main broadcasting network 210 has a main broadcasting
network transmission station 211, and a charged subscriber 212 (A1) and
an uncharged subscriber 213 (B1) receive the main broadcasting station Tll
transmitted by the main broadcasting network transmission station 211 as a
key value.
The repeating network 220 has a repeater station 221, and a charged subscriber 222 (A3) and an uncharged subscriber 223 (B3) receive the repeater station Tll transmitted by the repeater station 221 as a key value. In this instance, since a decrypting key value is transmitted from the
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user authentication server 131 to the charged subscriber 222 on the
repeating network 220 through the mobile communication network, the
charged subscriber 222 on the repeating network 220 can receive a
broadcasting service, but the uncharged subscriber 223 can receive no
broadcasting service because he has no decrypting key.
Also, in the superimposed area 230 of the main broadcasting network coverage and the repeating network coverage, the charged subscriber 231 (A2) and the uncharged subscriber 232 (B2) receive the main broadcasting station Tll from the main broadcasting network
transmission station 211 or repeater station Tll from the repeater station 221.
In other words, the embodiment of the present invention has a configuration allowing conditional access of the broadcasting network according to encryption and decryption, and the charged subscribers A1, A2,
and A3 can receive the main broadcasting station Tll, repeater station Tll,
and mobile communication decrypting key, and the uncharged subscribers B1, B2, and B3 can receive the main broadcasting station Tll and repeater station Tll, and as a result, as to the combination of received keys, the main broadcasting station Tll transmitted by the main broadcasting station or the
decrypting key received from the mobile communication network is
determined to be key combination to be decrypted.
FIG. 3 shows conditional access service availability for subscriber types and receiving locations according to an embodiment of the present invention.
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FIG. 3 shows combinations that are received according to the
subscriber receiver's locations and subscription types shown in FIG. 2. The
charged subscribers can receive services from both the main broadcasting
network and the repeating network, and the uncharged subscribers can
receive them from the main broadcasting network, thereby allowing the
conditional access to the respective transmitters.
FIG. 4 shows a block diagram for encrypted transmission and
receiving in a system for transmitting encrypted broadcast signals on a
single frequency network according to an embodiment of the present
invention.
Referring to FIG. 4, the data stream 410 on the transmission side is
through a scrambling process by the scrambler 430, and in this
instance, by the main broadcasting station's Tll value or the mobile
communication decrypting key 420. Here, the encrypting represents the
process of encrypting the multimedia data to be transmitted according to a
predetermined rule and modifying the signals so that the receiver who has no access rights may not view the encrypted data.
Also, regarding the key for decrypting the signals on the receiving
side, the descrambler 450 descrambles the encrypting according to the
main broadcasting station's Tll value or the mobile communication
decrypting key 440 to decrypt the signals into the original data stream 460.
In this instance, the uncharged subscriber can receive the main broadcasting station's Tll value, and the charged subscriber can receive
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both the main broadcasting station's Tll value and the mobile communication decrypting key.
Therefore, the uncharged subscriber can receive the main broadcasting station's Tll value from the main broadcasting network and
can receive no Tll value from the repeating network since the repeating
network transmits the repeater station Tll value that is different from the main broadcasting station Tll value to the uncharged subscriber. The charged subscriber can receive the Tll value from the main broadcasting network and can receive the same by using the decrypting key received
from the mobile communication network on the repeating network.
The problem on the transmission side is that the uncharged subscriber can receive the Tll value from the repeating network when the uncharged subscriber stores the Tll value received from the main broadcasting network and moves to the repeating network. In order to solve
the problem, an encrypting server in the main broadcasting station
periodically modifies the main broadcasting station Tll value and applies the modified Tll value to the encrypting of the corresponding data stream.
FIG. 5 shows an operational flowchart of a method for transmitting encrypted broadcast signals on a single frequency network according to an
embodiment of the present invention.
Referring to FIG. 5, in the method for transmitting encrypted broadcast signals on the SFN, service multiplexing is performed on the audio/video data to be transmitted by the service multiplexer of the main broadcasting station in step S501.
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The system multiplexer of the main broadcasting station multiplexes the service multiplexed data into broadcast signals in step S502.
The broadcast signals are encrypted and an encrypting key is
generated in step S503. In this instance, general encrypting methods are
applicable to the method for encrypting broadcast signals and generating an
encrypting key, which is obvious to a person skilled in the art and which will
not be described.
Tll is inserted into the encrypted broadcast signals in step S504 so
that the subscriber terminal may determine whether the encrypted
broadcast signals are transmitted through the main broadcasting network or
the repeating network. The encrypted broadcast signals and the main broadcasting station Tll are modulated into transmission signals in step S505.
The encrypted broadcast signals are transmitted to the uncharged
or charged subscriber through the main broadcasting network in step S506.
The decrypting key of the encrypted broadcast signals is provided
to the mobile communication system through a mobile communication
network or a private line in step S507. In this instance, when the encrypted
broadcast signals are conditionally accessible, the mobile communication
system transmits the decrypting key for decrypting the conditionally
accessible broadcast signals to the charged subscriber terminal according to a request by the charged subscriber terminal.
The main broadcasting station checks a predetermined period in step S508, modifies the main broadcasting station Tll for each
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predetermined period in step S509, and applies the modified main
broadcasting station Tll to scramble the broadcast signals in step S510.
Substantially, the modified Tll is inserted into the encrypted broadcast
signals and they are then transmitted.
In this instance, when the subscriber terminal is in the repeating
network, the mobile communication system transmits a decrypting key for decrypting the encrypted broadcast signals according to the request by the charged subscriber terminal. That is, as described above, when the uncharged subscriber terminal is in the repeating network, the access is
conditional because of the encrypted broadcast signals, it is needed to
change the uncharged subscriber terminal to a charged subscriber terminal so as to cancel the conditional access, and the encrypted broadcast signals can be decrypted after a decrypting key is provided from the mobile communication system.
While this invention has been described in connection with what is
presently, considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and
scope of the appended claims.
[INDUSTRIAL APPLICABILITY]
According to the present invention, the repeater service provider
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can activate repeater business when the repeater service provider provides charged repeater services according to the encrypted signal transmitting method on the SFN, and the main broadcasting network service provider can increase broadcasting networks.


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[CLAIMS]
1. In a system for transmitting broadcast signals on a single frequency network (SFN) for terrestrial and satellite digital broadcasting, a
system for transmitting encrypted broadcast signals on the SFN,
comprising:
a main broadcasting system for transmitting encrypted broadcast signals including data streams and transmitter identification information (Tll) through a main broadcasting network;
a repeating system for amplifying encrypted broadcast signals of
the main broadcasting network and transmitting the amplified broadcast signals, or modulating and amplifying streams input by the main broadcasting system through a private line and repeating broadcast signals of the main broadcasting system through a repeating network; and
a decrypting key provider for receiving a decrypting key value from
the main broadcasting or repeating system and transmitting a user authentication and decrypting key to a charged subscriber terminal through a mobile communication network.
2. The system of claim 1, wherein the main broadcasting system
comprises:
a service multiplexer for multiplexing audio, data, and video data respectively provided by a contents provider with related additional
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information;
a system multiplexer for multiplexing the data multiplexed by the service multiplexer into broadcast signals in a transmission frame format;
an encryptor for encrypting the broadcast signals transmitted by the
system multiplexer;
an encrypting key generator for generating an encrypting key from the system multiplexer;
a main broadcasting station Tll inserter for inserting transmitter identification information (Tll) to the encrypted broadcast signals;
a modulator for modulating the encrypted broadcast signals and
the inserted main broadcasting station Tll; and
a transmitter for transmitting the modulated broadcast signals to a subscriber through a main broadcasting network.
3. The system of claim 1, wherein the main broadcasting system
scrambles multimedia programs or contents and transmits a decrypting key for decrypting the broadcast signals according to a predetermined encrypting method.
4. The system of claim 1, wherein the main broadcasting system
and the repeating system respectively transmit transmitter identification information (Tll) for determining by the subscriber terminal whether the transmitted broadcast signals are main broadcasting network signals or repeating network signals.
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5. The system of claim 1, wherein the main broadcasting system
periodically modifies transmitter identification information (Tll) of the main
broadcasting system, and applies the modified Tll when corresponding
encrypting is performed.

6. The system of claim 1, wherein the main broadcasting system
applies transmitter identification information (Tll) as a key value of
transmission streams and enables conditional access to the respective
transmitters, the Tll being used for receiving different values from
transmitters on a single frequency network (SFN).
7. The system of claim 1, wherein the repeating system reallocates
a Tll value of the repeating system which is different from the Tll value of
the main broadcasting system and transmits the Tll value of the repeating
system when repeating the data stream of the main broadcasting system.
8. The system of claim 1, wherein the decrypting key provider
periodically transmits the decrypting key to a charged subscriber terminal
through a mobile communication network or the Internet.

9. In a method for transmitting broadcast signals on a single
frequency network (SFN) for terrestrial and satellite digital broadcasting, a
method for transmitting encrypted broadcast signals on the SFN
comprising:
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a) a system multiplexer of a main broadcasting station multiplexing service multiplexed data into broadcast signals;
b) encrypting the broadcast signals and generating an encrypting key;
c) inserting transmitter identification information (Tll) to the
encrypted broadcast signals so that a subscriber terminal may determine whether the encrypted broadcast signals are transmitted through a main broadcasting network or a repeating network;
d) transmitting the encrypted broadcast signals to an uncharged or
charged subscriber through the main broadcasting network; and
e) providing a decrypting key of the encrypted broadcast signals to
a mobile communication system through a mobile communication network
or a private line.
10. The method of claim 9, further comprising the main
broadcasting station periodically modifying the main broadcasting station Tll, applying the modified main broadcasting station Tll to scramble broadcast signals, and transmitting the encrypted broadcast signals.
11. The method of claim 9, further comprising the mobile
communication system transmitting a decrypting key for decrypting the encrypted broadcast signals according to a request by the charged subscriber terminal.
Dated this 20th day of September, 2007



26

ABSTRACT
"A SYSTEM FOR TRANSMITTING THE SCRAMBLED BROADCAST-SIGNALS IN SINGLE FREQUENCY NETWORK AND A METHOD
THEREOF"
Disclosed is a system for transmitting encrypted broadcast signals to different transmitters on a single frequency network (SFN) in a digital broadcasting system. The system for transmitting encrypted broadcast signals on the SFN includes: a main broadcasting system for transmitting encrypted broadcast signals including data streams and transmitter identification information (Tll) through a main broadcasting network; a repeating system for amplifying encrypted broadcast signals of the main broadcasting network and transmitting the amplified broadcast signals, or modulating and amplifying streams input by the main broadcasting system through a private line and repeating broadcast signals of the main broadcasting system through a repeating network; and a decrypting key provider for receiving a decrypting key value from the main broadcasting or repeating system and transmitting a user authentication and decrypting key to a charged subscriber terminal through a mobile communication network.
27

Documents:

1505-MUMNP-2007-ABSTRACT(17-6-2011).pdf

1505-MUMNP-2007-ABSTRACT(22-9-2011).pdf

1505-MUMNP-2007-ABSTRACT(GRANTED)-(23-9-2011).pdf

1505-mumnp-2007-abstract.doc

1505-mumnp-2007-abstract.pdf

1505-MUMNP-2007-CANCELLED PAGES(22-9-2011).pdf

1505-MUMNP-2007-CLAIMS(AMENDED)-(17-6-2011).pdf

1505-MUMNP-2007-CLAIMS(AMENDED)-(2-9-2011).pdf

1505-MUMNP-2007-CLAIMS(AMENDED)-(22-9-2011).pdf

1505-MUMNP-2007-CLAIMS(GRANTED)-(23-9-2011).pdf

1505-MUMNP-2007-CLAIMS(MARKED COPY)-(17-6-2011).pdf

1505-MUMNP-2007-CLAIMS(MARKED COPY)-(2-9-2011).pdf

1505-mumnp-2007-claims.doc

1505-mumnp-2007-claims.pdf

1505-MUMNP-2007-CORRESPONDENCE(11-7-2011).pdf

1505-mumnp-2007-correspondence(16-1-2008).pdf

1505-MUMNP-2007-CORRESPONDENCE(22-9-2011).pdf

1505-MUMNP-2007-CORRESPONDENCE(30-6-2011).pdf

1505-MUMNP-2007-CORRESPONDENCE(6-9-2011).pdf

1505-MUMNP-2007-CORRESPONDENCE(IPO)-(18-11-2011).pdf

1505-mumnp-2007-correspondence-others.pdf

1505-mumnp-2007-correspondence-received.pdf

1505-mumnp-2007-description (complete).pdf

1505-MUMNP-2007-DESCRIPTION(GRANTED)-(23-9-2011).pdf

1505-MUMNP-2007-DRAWING(17-6-2011).pdf

1505-MUMNP-2007-DRAWING(GRANTED)-(23-9-2011).pdf

1505-mumnp-2007-drawings.pdf

1505-MUMNP-2007-ENGLISH TRANSLATION(30-6-2011).pdf

1505-mumnp-2007-form 1(16-1-2008).pdf

1505-MUMNP-2007-FORM 1(17-6-2011).pdf

1505-MUMNP-2007-FORM 1(22-9-2011).pdf

1505-MUMNP-2007-FORM 1(6-9-2011).pdf

1505-mumnp-2007-form 13(24-9-2007).pdf

1505-mumnp-2007-form 13(6-9-2011).pdf

1505-MUMNP-2007-FORM 16(27-10-2011).pdf

1505-MUMNP-2007-FORM 2(GRANTED)-(23-9-2011).pdf

1505-MUMNP-2007-FORM 2(TITLE PAGE)-(17-6-2011).pdf

1505-MUMNP-2007-FORM 2(TITLE PAGE)-(22-9-2011).pdf

1505-MUMNP-2007-FORM 2(TITLE PAGE)-(24-9-2007).pdf

1505-MUMNP-2007-FORM 2(TITLE PAGE)-(GRANTED)-(23-9-2011).pdf

1505-mumnp-2007-form 26(16-1-2008).pdf

1505-MUMNP-2007-FORM 26(6-9-2011).pdf

1505-mumnp-2007-form 3(16-1-2008).pdf

1505-MUMNP-2007-FORM 3(17-6-2011).pdf

1505-MUMNP-2007-FORM 5(17-6-2011).pdf

1505-mumnp-2007-form-1.pdf

1505-mumnp-2007-form-13.pdf

1505-mumnp-2007-form-18.pdf

1505-mumnp-2007-form-2.doc

1505-mumnp-2007-form-2.pdf

1505-mumnp-2007-form-3.pdf

1505-mumnp-2007-form-5.pdf

1505-mumnp-2007-form-pct-ib-311.pdf

1505-mumnp-2007-form-pct-ipea-409.pdf

1505-mumnp-2007-form-pct-ipea-416.pdf

1505-mumnp-2007-form-pct-isa-237.pdf

1505-MUMNP-2007-NOTARIAL CERTIFICATE(6-9-2011).pdf

1505-mumnp-2007-pct-search report.pdf

1505-MUMNP-2007-PETITION UNDER RULE 137(17-6-2011).pdf

1505-MUMNP-2007-REPLY TO EXAMINATION REPORT(17-6-2011).pdf

1505-MUMNP-2007-REPLY TO HEARING(2-9-2011).pdf

1505-MUMNP-2007-US OFFICE ACTION & PRIORITY DOCUMENT(17-6-2011).pdf

1505-mumnp-2007-wo international publication report(16-1-2008).pdf

abstract1.jpg


Patent Number 249029
Indian Patent Application Number 1505/MUMNP/2007
PG Journal Number 39/2011
Publication Date 30-Sep-2011
Grant Date 23-Sep-2011
Date of Filing 24-Sep-2007
Name of Patentee KTFREETEL CO. LTD.
Applicant Address A KOREAN COMPANY, 7-18,SINCHEON DONG, SONGPA-GU, SEOUL 138 240, KOREA
Inventors:
# Inventor's Name Inventor's Address
1 HONG CHUNG - PYO BYEOKSAN APT. 518-1201, SIHEUNG 2-DONG, GEUMCHEON-GU, SEOUL 153-766
2 LEE HYUN SAEMMEORI APT. 108-602, DOONSAN-DONG, SEO-GU, DAEJEON-CITY 302-120
3 LEE GWANG - SOON YEOLMAE MAEUL 3-DANJI 407-302, JIJOK-DONG, YUSEONG-GU, DAEJEON-CITY 305-770
4 PARK WON - JIN WOOSEONG APT. 227-1502, 96, SEOHYEON-DONG,BUNDANG-GU, SEONGNAM-CITY, GYEONGGI-DO 463-773
5 LEE BONG - HO SONGGANG CHEONGSOL APT. 512-1108, SONGGANG-DONG, YUSEONG-GU,DAEJEON-CITY 305-752
6 CHAE TAE - JUNE JANGMI APT. 8-603, ZAMSHIL 6-DONG, SONGPA-GU, SEOUL 135-796
7 LEE SOO - IN CLOVER APT. 106-606, DOONSAN-DONG, SEO-GU, DAEJEON-CITY 302-120
8 LIM JONG - SOO EXPO APT. 301-201, JEONMIN-DONG, YUSEONG-GU, DAEJEON-CITY 305-761
PCT International Classification Number H04N7/16
PCT International Application Number PCT/KR2005/003716
PCT International Filing date 2005-11-04
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10-2005-0024433 2005-03-24 Republic of Korea