WO2016095999A1

WO2016095999A1 - Indoor distribution of a broadband signal

Info

Publication number: WO2016095999A1
Application number: PCT/EP2014/078311
Authority: WO
Inventors: Pietro Obino; Ferruccio ANTONELLI; Alessandro TOSTI; Renzo LATTANZI; Sebastiano CIOTTI; Marco CARLUCCI
Original assignee: Telecom Italia S.P.A.
Priority date: 2014-12-17
Filing date: 2014-12-17
Publication date: 2016-06-23

Abstract

It is disclosed a system for distribution of a broadband signal of a mobile radio communication network to at least one subscriber device located in an indoor environment, the broadband signal comprising a data stream. The system includes: an outdoor module configured to receive the broadband signal, extract from it the data stream, encapsulate the data stream into Ethernet data frames and use the Ethernet data frames for modulating at least one carrier signal adapted for being transmitted over a link of the indoor environment together with a further signal; and an indoor module connected to the outdoor module via the link, the indoor module being configured to separate the at least one received modulated carrier signal and the received further signal, extract from the at least one received modulated carrier signal the Ethernet data frames and make them available to the at least one subscriber device.

Description

INDOOR DISTRIBUTION OF A BROADBAND SIGNAL

Technical field

The present invention relates to the field of mobile radio communication networks. In particular, the present invention relates to a system and method for indoor distribution of a broadband signal, in particular a broadband signal of a third or fourth generation mobile radio communication network. Background art

As known, third and fourth generation mobile radio communication networks allow high-speed internet access to mobile phones and data terminals.

In this scenario, a problematic issue is the distribution of the broadband signals generated by said networks in indoor environments (e.g. buildings) where the signals can experience significant attenuations mainly due to wall reflection and wall penetration. For example, in case of LTE signals, they achieve their maximum strength outdoor, especially on the rooftops of buildings, while indoor the LTE signals may be lower than -100 dBm.

A way to improve the indoor coverage of a mobile radio communication network is to introduce inside buildings repeaters such as picocells, which are available for most technologies including LTE. Solutions are also known which allow distributing a wireless signal to a location over a coaxial cable. In particular, coaxial cables are typically used for the distribution of a digital television signal (DTV signal), such as the Digital Video Broadcasting - Terrestrial (DVB-T) signal.

For example, US2013/0070772 A1 discloses a system and method for distributing signals from a first communications network and a second communications network to a location, including a base transceiver station configured to receive a signal from the first communications network and convert the signal into an RF signal for transmission to a mobile terminal, the RF signal having an RF frequency above a threshold frequency, and a coupling module configured to: receive the RF signal from the base transceiver station and receive a data signal from the second communications network, the data signal having an RF frequency below the threshold frequency; combine the RF signal and the data signal into a combined signal with the RF signal and data signal each retaining their respective frequencies; and provide the combined signal over a coaxial cable link to the location.

Moreover, US20070223429 discloses a wireless local area network access point having a data communication network input to provide, for example, broadband access via a digital subscriber line modem, a cable modem, or the like. The access point also has a wireless local area network output to provide wireless access to this broadband resource and a hard-wired local area network output to provide wired access. In a preferred approach the latter couples to a cable television coaxial cable that carries a plurality of cable television service provider channels within a predetermined frequency band. Access to the broadband resource comprises use of a carrier that is out of band with respect to that predetermined frequency band.

Summary of the invention

The Applicant has tackled the problem of improving the provision of broadband services in indoor environments. In the following description and in the claims, the expression "indoor environment" will indicate the interior of a construction such as a building (e.g. an apartment block, an office building, an industrial plant, a store, or the like) or an underground location. In particular the Applicant has tackled the problem of making a broadband connection readily available in indoor environments not reached by a physical network infrastructure and where broadband coverage is already present but broadband signal power is very low (e.g. lower than -l OOdBm).

The Applicant has solved this problem by providing a system and method for indoor distribution of a broadband signal, that exploits a link that is natively existing or at least already existing in the indoor environment at the time of the deployment of the system of the present invention, this pre-existing link being adapted for distributing inside the indoor environment a further signal, such as for example a television signal.

Specifically, the system according to the present invention comprises an outdoor module and one or more indoor modules. In a preferred embodiment, the outdoor module is placed outside the indoor environment, for example outside a building and in particular on the rooftop of the building in a position that maximizes the reception of the broadband signals coming from a mobile radio communication network. According to other embodiments, the outdoor module may also be placed inside the indoor environment, provided that its location is such that a cellular antenna included in the outdoor module may receive the broadband signals coming from the mobile radio communication network and the pre-existing link is accessible. The indoor modules are located inside the indoor environment. Preferably, the outdoor module and the indoor modules are connected by means of a link, this link being pre-existing in the indoor environment with respect to the deployment of the system. Preferably each indoor module is configured to be connected, on one side, to the outdoor module by means of the pre-existing link and, on the other side, to a number of subscriber devices either through a wired connection (e.g. an Ethernet connection) or through a wireless connection (e.g. a Wi-Fi connection).

In the downlink direction, the system of the present invention advantageously allows transmitting a data stream (for instance an IP data stream) coming from the mobile radio communication network inside the indoor environment though the pre-existing link. Specifically, at the outdoor module the broadband signal coming from the mobile radio communication network is processed so as to extract from it the data stream that is then encapsulated into Ethernet data frames. The Ethernet data frames are then modulated according to an OFDM (Orthogonal Frequency Division Multiplexing) technique for being transported over the pre-existing link, together with the coexisting signal (e.g. the television signal), to the indoor modules and, through either the wired connection or the wireless connection, to the users of the mobile communication network.

The system of the present invention can also operate in the uplink direction.

In the following description and in the claims, the expression "broadband signal" will indicate a signal of a broadband mobile radio communication network, e.g., a signal of a third or fourth generation mobile radio communication network where by "third generation mobile radio communication network" it is meant a telecommunication network compliant with the UMTS standard and evolutions thereof and by "fourth-generation mobile radio communication network" it is meant a telecommunication network compliant with the LTE / LTE-A standard and evolutions thereof.

The expression "service provider" will indicate a provider (e.g. a telecommunication company) of telecommunication services such as broadband services.

The expression "pre-existing link" or "pre-existing cable" will indicate a link or cable that is natively existing or at least already existing in the indoor environment at the time of the deployment of the system of the present invention, the pre-existing link or cable being adapted for distributing inside the indoor environment a given signal such as for example a television signal.

The term "data" will indicate digital data, if not otherwise specified.

According to a first aspect, the present invention provides a system for distribution of a broadband signal of a mobile radio communication network to at least one subscriber device located in an indoor environment, the broadband signal comprising a data stream and the system including:

- an outdoor module configured to receive the broadband signal, extract from it the data stream, encapsulate the data stream into Ethernet data frames and use the Ethernet data frames for modulating at least one carrier signal adapted for being transmitted over a link of the indoor environment together with a further signal; and

- an indoor module connected to the outdoor module via the link, the indoor module being configured to separate the at least one received modulated carrier signal and the received further signal, extract from the at least one received modulated carrier signal the Ethernet data frames and make them available to the at least one subscriber device.

Preferably, the link is a pre-existing link, more preferably a coaxial cable link or alternatively, a power line or a copper pair link.

Preferably, the outdoor module is connected to a television antenna and the further signal is a digital television signal.

Preferably, the outdoor module comprises a subscriber identity module for identifying and authenticating the at least one subscriber or at least one subscriber device to the mobile radio communication network, the outdoor module being further configured to establish a connection with the mobile radio communication network by means of the subscriber identity module.

Preferably, the outdoor module is further configured to associate with each Ethernet data frame an indoor module identifier indicative of the indoor module to which the Ethernet data frame are addressed.

Preferably, the outdoor module is further configured to apply an OFDM modulation technique for modulating the at least one carrier signal.

Preferably, the outdoor module comprises a band pass filter configured to filter the at least one modulated carrier signal and a high pass filter configured to filter the further signal.

According to embodiments of the present inventions, a frequency of the carrier signal is comprised between about 5 MHz and about 95 MHz and the band pass filter has a bandwidth comprised between about 5 MHz and about 95 MHz.

According to embodiments of the present invention, the high pass filter has a cutoff frequency equal to about 130 MHz.

Preferably, the outdoor module is further configured to multiplex the at least one filtered modulated carrier signal and the filtered further signal and send a resulting multiplexed signal on the pre-existing link towards the indoor module.

Preferably, the indoor module comprises a first filter configured to filter the resulting multiplexed signal so as to recover the at least one modulated carrier signal, and a second filter configured to filter the resulting multiplexed signal so as to recover the further signal.

Preferably, the indoor module is further configured to forward the Ethernet data frames to the subscriber device through a wired connection or a wireless connection.

Preferably, the mobile radio communication network is a third or fourth generation mobile radio communication network. According to a second aspect, the present invention provides a method for distribution of a broadband signal of a mobile radio communication network to at least one subscriber device located in an indoor environment, the broadband signal carrying a data stream, the method comprising:

- extracting from the broadband signal the data stream;

- encapsulating the data stream into Ethernet data frames;

- using the Ethernet data frames for modulating at least one carrier signal adapted for being transmitted over a link of the indoor environment together with a further signal;

- separating the at least one modulated carrier signal and the further signal;

- extracting from the at least one modulated carrier signal the Ethernet data frames; and

- making the Ethernet data frames available to the subscriber device.

Brief description of the drawings

The present invention will become clearer from the following detailed description, given by way of example and not of limitation, to be read with reference to the accompanying drawings, wherein:

- Figure 1 shows a generic scenario in which a system for the indoor distribution of a broadband signal according to the present invention is used;

- Figure 2 is a block scheme of the system of Figure 1 ;

- Figure 3 shows an electrical circuit diagram of a diplexer for an outdoor module of the system of Figure 2;

- Figure 4 is a block scheme of an indoor module of the system of Figure 2; and

- Figures 5a and 5b show electrical circuit diagrams of filters for the indoor module of Figure 4. Detailed description of preferred embodiments of the invention

Figure 1 shows a generic scenario in which a system 1 for indoor distribution of broadband signals of a mobile radio communication network 2 is used. According to the present invention, the mobile radio communication network 2 is a third generation (3G) or fourth generation (4G) mobile radio communication network, where by "third generation mobile radio communication network" it is meant a telecommunications network compliant with the UMTS standard and evolution thereof and by "fourth-generation mobile radio communication network" it is meant a telecommunications network compliant with the LTE / LTE-A standard and evolutions thereof.

The system 1 according to the present invention is configured to provide indoor distribution of the broadband signals of the mobile radio communication network 2 to a number of subscriber locations 3a_j, j=1 , M, wherein M is an integer number equal to or greater than 1 , placed inside a building 3, which may be an apartment block, an industrial plant, a store, or the like.

The system 1 preferably comprises an outdoor module 4 and one or more indoor modules 5,, i=1 , N, wherein N is an integer number equal to or greater than 1 . According to embodiments of the present invention, the outdoor module 4 is configured to be located outside the building 3. In particular, the outdoor module 4 is configured to be located on the rooftop of the building 3 in a position that maximizes the reception of the broadband signals coming from the mobile radio communication network 2 or in another position that provides a good reception of the broadband signals coming from the mobile radio communication network 2, while allowing a convenient access and connection to the distribution link 8 that will be described in the following. The indoor modules 5,, i=1 , N are configured to be located inside the subscriber locations 3a_j, j=1 , M. For instance, if the building 3 is an apartment block, the indoor modules 5,, i=1 , N may be located inside the apartments, and/or inside different rooms of an apartment, and/or in correspondence of the ground floor of the apartment block. In an office building, the indoor modules 5,, i=1 , N may be located inside different offices placed at different floors or at the same floor, or they may be located each in correspondence of a respective floor. In an industrial plant or a store, the indoor modules 5,, i=1 , N may be located inside different areas or rooms.

Figure 1 schematically shows an exemplary scenario in which the building 3 comprises four subscriber locations 3a-i, 3a₂, 3a₃, 3a₄ and the system 1 comprises one outdoor module 4 located on the rooftop of the building 3 and four indoor modules 5- , 5₂, 5₃, 5₄, each placed inside a respective subscriber location 3a-i, 3a₂, 3a₃, 3a₄.

Preferably, the outdoor module 4 and the indoor modules 5,, i=1 , 4 are connected by means of a link, this link being typicaly, although not exclusively, pre-existing in the building 3 with respect to the deployment of the system 1 according to the present invention. The indoor modules 5i, i=1 , 4 are physically connected to this link by means of plugs (not shown in the Figure) typically already present inside the building 3.

Preferably, the link connecting the outdoor module 4 and the indoor modules 5i, 5₂, 5₃, 5 is a coaxial cable link. According to alternative embodiments, the link connecting the outdoor module 4 and the indoor modules 5<_\, 5₂, 5₃, 5₄ can be a power line. A link comprising a copper pair can be used as well.

According to the exemplary scenario depicted in Figure 1 , the outdoor module 4 is connected to a television antenna 6 configured to receive a television signal, typically a digital television (DTV) signal, for instance a DVB-T signal, from a television network 7, and to the indoor modules 5i, 5₂, 5₃, 5₄. The link connecting the outdoor module 4 and the indoor modules 5- , 5₂, 5₃, 5₄ is a coaxial cable link carrying out the television signal to each subscriber locations 3a_j. In Figure 1 this link is generically indicated by reference "8".

Again with reference to Figure 1 , at each subscriber locations 3a_j, a respective indoor module 5, is preferably configured to be connected on one side to the outdoor module 4 by means of the link 8 and on the other side to a number of subscriber devices 3b either through a wired connection 9a or through a wireless connection 9b. For the purpose of the present invention, a subscriber device may be any of the following: a television equipment, a personal computer, a mobile telephone, a smartphone, a tablet, or the like. A wired connection 9a between an indoor module 5, and a subscriber device 3b may be implemented by means of, for example, a twisted pair cable or a coaxial cable. A wireless connection 9b may be implemented, e.g., as a wireless local area network (WLAN) connection according to the IEEE 802.1 1 - 2012 standard. Within the exemplary scenario of Figure 1 , the first indoor module 5i inside the first subscriber location 3ai is connected to a smartphone through a wireless connection, the second indoor module 5₂ inside the second subscriber location 3a₂ is connected to a personal computer through a twisted pair cable and to a television equipment through a coaxial cable, the third indoor module 53 inside the third subscriber location 3a₃ is connected to a smartphone through a wireless connection and to a television equipment through a coaxial cable and the fourth indoor module 5₄ inside the fourth subscriber location 3a₄ is connected to a personal computer through a twisted pair cable.

The system 1 of the present invention is preferably configured to operate in the downlink as well as the uplink direction of communication to support exchanging data between the mobile radio communication network 2 and the subscriber devices 3b. Data may be related to different broadband services provided to the subscribers of the mobile radio communication network 2 such as for example a connection to the Internet.

Figure 2 shows a block scheme of the outdoor module 4 according to a preferred embodiment of the present invention.

The outdoor module 4 is preferably arranged inside a waterproof box (not shown in the Figures) and is configured to be an always-on device. The outdoor module 4 preferably comprises a cellular antenna 41 , a first outdoor modem 42, a control sub-module 43, an administration interface 44, a second outdoor modem 45, an outdoor diplexer 46 and a power supply unit PS.

The power supply unit PS is preferably connected on one side to an electrical distribution grid (e.g. providing an AC voltage of 230 V at a frequency equal to 50 Hz), and on the other side to the other components of the outdoor module 4.

According to an alternative embodiment, the power supply unit may be an external low power unit (e.g. 12 V DC voltage unit) for outdoor applications. According to an even alternative embodiment, the outdoor module may be powered by a remote power feeding through the coaxial cable connecting the outdoor module and the indoor modules. Such an arrangement may be advantageous in case no voltage source is available at the outdoor module. According to this embodiment, a power supply unit is also located inside one or more of the indoor modules 5,, i=1 , 4. It may be also located outside the indoor modules 5, as a separate unit cooperating with the indoor modules 5,.

Again with reference to Figure 2, the cellular antenna 41 is preferably connected to a first port of the first outdoor modem 42 that has a second port connected to a first port of the control sub-module 43. The connection between the first outdoor modem 42 and the control sub- module 43 is preferably implemented by means of a serial bus in connection with, for instance, a Universal Serial Bus (USB) interface or a Peripheral Component Interconnect Express (PCIe) interface. The control sub-module 43 preferably cooperates with the administration interface 44. Moreover, the control sub-module 43 has a second port connected to a first port of the second outdoor modem 45. The connection between the control sub-module 43 and the second outdoor modem 45 is preferably implemented by an Ethernet cable. The second outdoor modem 45 has a second port connected to a first port of the outdoor diplexer 46 having a second port connected to the television antenna 6 and a third port connected, by means of the link 8, to the indoor modules 5,.

According to an exemplary arrangement, the cellular antenna 41 comprises two antenna elements arranged at a given geometry and placed at a relative given distance (e.g. in the range 5-10 cm) in order to implement a Multiple Input-Multiple Output (MIMO) 2x2 system. Such a cellular antenna is known for use with 2G, 3G and 4G cellular devices and hence will not be described in greater detail hereinafter.

Preferably, the cellular antenna 41 is embedded within the outdoor module 4. More preferably, the cellular antenna 41 is placed inside the waterproof box. According to an alternative arrangement, the cellular antenna 41 may be placed outside the waterproof box. According to advantageous embodiments of the present invention, the position and orientation of the cellular antenna 41 is adjustable in order to optimize reception of the signals generated by the mobile radio communication network 2.

Preferably, the first outdoor modem 42 comprises a subscriber identity module SIM that includes the information required for identifying and authenticating to the mobile radio communication network 2 the subscriber, or one or more of the subscriber devices 3b located inside the subscribers location 3a_j. These information may typically comprise the IMSI (International Mobile Subscriber Identity) and a related key. The SIM is, typically although not exclusively, in the form of an integrated circuit embedded into a removable plastic card.

According to the present invention, the outdoor module 4 is configured to host different kinds of modem operating as the first outdoor modem 42. For this purpose, a modem dedicated standard universal expansion slot is preferably reserved in the outdoor module electronic board. In this way, since the wide majority of commercial modems share the same physical interfaces (USB interface and/or PCIe interface), replacement products may be installed inside the outdoor module from several modem vendors.

Preferably, the control sub-module 43 is a microcomputer which is configured to run an operating system such as, for instance, a Linux operating system. The control sub-module 43 may be implemented as an ARM (Advanced Rise Machine) based processor or a x86 based processor or a PowerPC based processor or according to other known architectures.

The administration interface 44 is preferably in the form of a web page stored on an web server (not shown in the Figures). The web server may be a remote web server or a web server internal to the outdoor module 4.

The administration interface 44 can be accessed by a remote client, which may be for example an administration personnel of a remote operator or a remote system, able to manage and configure broadband services offered through the mobile radio telecommunication network 2. In particular, the administration interface 44 may be accessed through a secure and authenticated login, for instance by using username and password over a secure connection established through a secure protocol such as HTTPS or SSL.

Figure 3 shows an outdoor diplexer 46 according to an embodiment of the present invention. The outdoor diplexer 46 preferably comprises a first branch 46a connected between the first port and the third port of the outdoor diplexer 46 and a second branch 46b connected between the second port and the third port of the outdoor diplexer 46. The first branch 46a comprises a band pass filter 47 and the second branch 46b comprises a high pass filter 48. According to an embodiment of the present invention, the band pass filter 47 comprises a first capacitance C1 1 , a second capacitance C12, a third capacitance C13 and an inductance L1 arranged as shown in Figure 3. In particular, the first capacitance C1 1 is connected, on one side, to the first port of the outdoor diplexer 46 and on the other side to the ground G. The second capacitance C12 and the inductance L1 are connected in a parallel configuration between the first capacitance C1 1 and the third capacitance C13, which is also connected to the third port of the outdoor diplexer 46.

Again with reference to Figure 3, the high pass filter 48 comprises a first capacitance C21 , an inductance L2 and a second capacitance C22 arranged according to a "T" configuration. In particular, the first capacitance C21 is connected, on one side, to the second port of the outdoor diplexer 46 and, on the other side, to the inductance L2. The second capacitance C22 is connected, on one side, to the inductance L2 and, on the other side, to the third port of the outdoor module 46. The inductance L2 is also connected to the ground G.

The bandwidth of the band pass filter 47 is preferably comprised between about 5MHz and about 95 MHz while the high pass filter 48 has preferably a cut-off frequency equal to about 130 MHz.

Figure 4 schematically shows an indoor module 5, according to the present invention.

The indoor module 5, is connected to the outdoor module 4 by means of the link 8 and to subscriber devices 3b by means of wired and wireless connections 9a, 9b. The indoor module 5, preferably comprises an indoor diplexer 51 and an indoor modem 52. In turn, the indoor diplexer 51 can comprise a first filter 51 a and a second filter 51 b.

In the exemplary arrangement of Figure 4, the first filter 51 a of the indoor diplexer 51 has a first port connected to the link 8 and a second port connected to a first port of the indoor modem 52. The indoor modem 52 has a second port connected to a subscriber device 3b, such as a personal computer or a television equipment, by means of a wired connection 9a.

Optionally, the indoor modem 52 may be connected in cascade to an access point 53 providing a wireless connection 9b with a subscriber device 3b such as a smartphone or a tablet. The access point 53 may be a Wi-Fi access point.

Again with reference to the exemplary arrangement of Figure 4, the second filter 51 b of the indoor diplexer 51 has a first port connected to the link 8 and a second port connected to a subscriber device 3b, such as a personal computer or a television equipment, by means of a wired connections 9a.

The first filter 51 a and the second filter 51 b are schematically represented in Figures 5a and 5b, respectively. Preferably, the first filter 51 a is a band pass filter while the second filter 51 b is a high pass filter. According to an embodiment of the present invention, the electronic circuit of the first filter 51 a comprises a first capacitance C1 V, a second capacitance C12', a third capacitance C13', a fourth capacitance C14, an inductance L1 ' and a resistance R1 , arranged as shown in Figure 5a. In particular, the first capacitance C1 V is connected, on one side, to the first port of the first filter 51 a and on the other side to a parallel circuit comprising the second capacitance C12' and the inductance L1 . The parallel circuit comprising the second capacitance C12' and the inductance L1 is also connected in series to the third capacitance C13' that, in turn, is connected to the first port of the indoor modem 52 and the ground G through the series between the resistance R1 and the fourth capacitance C14.

According to an embodiment of the present invention the electronic circuit of the second filter 51 b comprises a first capacitance C21 ', a second capacitance C22', a third capacitance C23 and an inductance L2' arranged in a "T" configuration as shown in Figure 5b. In particular, the first capacitance C21 ' is connected, on one side, to the first port of the second filter 51 b and on the other side to the second capacitance C22', which is also connected to the second port of the filter 51 b. The first capacitance C21 ' is also connected to the ground G through the series between the inductance L2' and the third capacitance C23.

Preferably, the first filter 51 a has a bandwidth comprised between about 5 MHz and about 95 MHz. Preferably, the second filter 51 b has a cutoff frequency equal to about 130 MHz.

The structure of the indoor module 5i shown in Figure 4 and described above is merely exemplary. In general, according to the present invention, the indoor module 5i may offer to the subscriber devices 3b different connection capabilities (such as, for instance, coaxial cable, twisted pair cable, wireless connection, power line).

Herein after, a description of the operation of the system 1 in the downlink direction will be provided.

In the downlink direction, the outdoor module 4 is configured to receive a first signal from the mobile radio communication network 2 via the cellular antenna 41 and a second signal from the television network 7 via the television antenna 6 and to distribute said first and second signals to the indoor modules 5,, i=1 , 4 over the coaxial cable link 8, as it will be described herein after. As already mentioned, in a preferred embodiment, the first signal is a mobile radio broadband signal, typically generated by a third or fourth generation mobile radio communication network and the second signal is a television signal. Each indoor module 5, is configured to receive said first and second signals from the outdoor module 4 and to transmit them to a number of subscriber devices 3b connected thereto.

More in detail, in the downlink direction, the first signal carries first data, said first data preferably comprising a first digital data stream, in particular an IP data stream and, more in particular, an Internet Protocol payload transmitted by a service provider to subscriber devices 3b located inside the building 3.

Once the first signal is acquired by the cellular antenna 41 , the first outdoor modem 42, by exploiting the information contained in the embedded SIM (such as the IMSI and the related key), preferably establishes a connection between the mobile radio communication network 2 and the control sub-module 43. Thanks to the fact that the connection between the first outdoor modem 42 and the control sub- module 43 is implemented by means of a serial bus in connection with, for instance, a Universal Serial Bus (USB) interface or a Peripheral Component Interconnect Express (PCIe) interface, a fast network connection between the mobile radio communication network 2 and the control sub-module 43 can be established (e.g., up to 100Mbit/s over 4G).

Then, the first outdoor modem 42 preferably decodes the first signal in order to extract from it the first digital data stream. This is a standard operation for a modem of a mobile radio communication network, such as, for instance, a LTE network, and hence it will not be described in further detail herein after.

Successively, the first outdoor modem 42 preferably sends the extracted first digital data stream to the control sub-module 43.

The control sub-module 43 is preferably configured to act as a configurable router for the data traffic exchanged between the mobile communication network 2 and the subscriber devices 3b. In particular, in the downlink direction, the control sub-module 43 is preferably configured to receive the first digital data stream from the first outdoor modem 42, to encapsulate the first digital data stream into Ethernet data frames and to send the Ethernet data frames so generated to the second outdoor modem 45. The control sub-module 43 is further configured to associate with each Ethernet data frame an indoor module identifier (for example, a MAC address) representative of the indoor module 5, to which the Ethernet data frame is addressed.

The control sub-module 43 can also be configured to provide different type of services to each one of the indoor modules 5i/subscriber devices 3b. For example the control sub-module 43 can be configured to set the maximum bandwidth available for each indoor module 5i. Preferably, setting the maximum bandwidth available for an indoor module 5i comprises assigning, via the administration interface 44, a maximum data bitrate to the data traffic pertaining to that indoor module, for example on the basis of the type of data traffic generated by the indoor module or on the basis of commercial parameters.

Moreover, the control sub-module 43 can be configured to monitor and log the data traffic generated by each indoor module 5i. Preferably, monitoring the data traffic generated by an indoor module 5i comprises accessing, via a specific software application running on the administration interface 44, the data traffic pertaining to that indoor module and then storing information on said data traffic on a file system comprised within the control sub-module 43.

Further, the control sub-module 43 can be configured to monitor and store all the information required by law regulations. More in particular, the control sub-module 43 can be configured to store and keep in encrypted form information concerning the data traffic generated by the subscriber devices 3b that can be requested from legal authorities when needed. The monitoring of this data traffic may be performed by a monitoring storage software module comprised within the control sub- module 43 and implementing an IT infrastructure management system, such as the known Nagios® management system (www.naqios.org) while the storing of this information may be performed by a storage software module which may be based on an encryption tool such as the known OpenSSL implementation.

The control sub-module 43 can also be configured to handle and monitor all the processes needed for the operation of the system 1 . This monitoring can comprise monitoring process parameters, such as: transmission bands associated to each indoor module 5,, time of use of each indoor module 5,, quality of the received radio signal, condition of the cellular antenna 41 .

Further, the control sub-module 43 can be configured to cooperate with the administration interface 44, as it will be described herein after. As already stated above, the administration interface 44 can be in the form of a web page stored on a web server (not shown in the Figures) and the control sub-module 43 is preferably configured to update this web page by executing and displaying a set of software interfaces that read data such as: number of active subscriber devices 3b/indoor modules 5i; status of each indoor module 5i (e.g. operation mode/idle mode), network traffic generated by each indoor module 5i. The control sub-module 43 can be further preferably configured to communicate these data to a central system of a service provider via the mobile radio communication 2.

The administration interface 44 provides an interface to the remote client for the following functionalities/services provided by the control sub-module 43:

access to information, stored in the file system of the control sub- module 43, on current and previous data traffic generated by each indoor module 5, and used bandwidth;

- review and edit of the network profiles of the users connected to the mobile radio communication network 2 via the system 1 , these profiles being stored in the file system of the control sub-module 43 and used for statistics, customer support, accounting and possibly, in combination with the subscriber identity module, for authentication of the individual indoor modules 5i/subscriber devices 3b;

check of the status of the connection between the system 1 and the mobile radio communication network 2;

selective allocation of the radio resources among the indoor modules 5,;

activation/deactivation of indoor modules 5,;

set of the maximum bandwidth available for each indoor module 5,; access to system logs.

The second outdoor modem 45 is configured to receive the Ethernet data frames generated by the control sub-module 43 and to encode them on at least one carrier signal for the transmission over the coaxial cable link 8 connecting the outdoor module 4 and the indoor module 5, to which the Ethernet data frames are addressed. Preferably, the Ethernet data frames are used for modulating the at least one carrier signal. Preferably, the Ethernet data frames are encoded over a number of carrier signals according for example to an OFDM modulation, as provided by the ITU-T G.hn standard (see, for instance, Ben-Tovim, Erez "ITU G.hn - Broadband Home Networking". In Berger, Lars T.; Schwager, Andreas; Pagani, Pascal et al. MIMO Power Line Communications: Narrow and Broadband Standards, EMC, and Advanced Processing. Devices, Circuits, and Systems. CRC Press. ISBN 9781466557529. February 2014). For instance, a known M-QAM (Quadrature Amplitude Modulation) modulation format may be used, with M being an integer number equal to 4, 16, 64, 256 or 1024. In particular, the Ethernet data frames are encoded over a number of carrier signals with frequencies comprised between a first frequency and a second frequency. Preferably, the first frequency is equal to about 5 MHz and the second frequency is equal to about 95 MHz.

The second outdoor modem 45 is then configured to send the resulting modulated signal to the outdoor diplexer 46.

The outdoor diplexer 46 is preferably configured to receive the modulated signal from the second outdoor modem 45 and the second signal from the television antenna 6. For the purpose of the present invention, the second signal is a television signal, typically a digital television signal, such as a DVB-T signal. More specifically, said second signal is an OFDM modulated signal which is transmitted over a frequency band between about 174 MHz and 870 MHz. Such second signal may be amplified by a standard amplifier (not shown in the Figures) placed along the link 8 connecting the television antenna 6 to the outdoor diplexer 46.

The outdoor diplexer 46 is also configured to filter the modulated signal received from the second outdoor modem 45 by means of the band pass filter 47 and to filter the television signal received from the television antenna 6 by means of the high pass filter 48.

The outdoor diplexer 46 is also configured to multiplex the filtered signals onto its third port and then to send the resulting multiplexed signal over the link 8 towards the designated indoor module 5,.

The operation of a diplexer is known and hence it will not further described hereinafter.

It should be noted that using the OFDM technique for modulating the first signal in connection with the filtering operations described above advantageously guarantees that, over the link 8, the first and second signals do not interfere with each other because their bandwidths are separated in frequency so as to avoid overlap.

In the downlink direction, each indoor module 5i is configured to receive the multiplexed signal coming from the outdoor module 4 over the link 8 and to demultiplex the received signal by means of the respective indoor diplexer 51 .

More in detail, the indoor diplexer 51 is configured to demultiplex the received signal into a first demultiplexed signal and a second demultiplexed signal corresponding, respectively, to the modulated signal generated at the second outdoor modem 45 and to the television signal coming from the television antenna 6.

The demultiplexing of the received signal is performed by the first filter 51 a and the second filter 51 b of the indoor diplexer 51 .

In particular, the first filter 51 a filters out from the received signal the modulated signal generated at the second outdoor modem 45, while the second filter 51 b filters out from the received signal the television signal coming from the television antenna 6.

The first filter 51 a is further configured to provide the first demultiplexed signal to the indoor modem 52.

In turn, the indoor modem 52 is configured to decode the first demultiplexed signal in order to extract from it the Ethernet data frames (comprising possible errors due to transmission over the link 8) addressed to the subscriber devices 3b that are connected to the considered indoor module 5i.

More in detail, the indoor modem 52 is configured to forward the recovered Ethernet data frames to wired subscriber devices 3b, such as personal computers or television equipment by means of wired connections 9a, and/or to the optional access point 53 providing a wireless connection 9b to wireless subscriber devices 3b such as smartphones or tablets (see for instance the first and third indoor modules 5i, 5₃ in Figure 1 ).

The second filter 51 b is preferably configured to provide the second demultiplexed signal to wired subscriber devices 3b, such as personal computers or to a television equipment by means of wired connections 9a (see, for instance, the second and fourth indoor modules 52, 53 in Figure 1 ).

In the uplink direction, each indoor module 5, is preferably configured to receive broadband signals carrying out data addressed to the mobile radio communication network 2 from a number of subscriber devices 3b connected thereto either through a wired connection 9a and/or a wireless connection 9b. Each indoor module 5, is further preferably configured to generate a corresponding data stream and to send it to the outdoor module 4 over the link 8, e.g., through OFDM modulation of a carrier signal, similar to operation in the downlink direction. The outdoor module 4 is in turn configured to send said data stream to the mobile radio communication network 2 using the data protocol supported by the mobile radio communication network 2.

As a skilled person may appreciate, the system of the present invention may operate in different scenarios. In particular, as already mentioned above, according to other embodiments not shown in the Figures, the link used for connecting the outdoor module to the indoor modules may be a power line or a copper pair, which is pre-existing in the considered indoor environment.

Advantageously, the system of the present invention is also capable of supporting different levels of service for the different users/subscriber devices 3b and remote management features required by a service provider/operator. In fact, the presence of the control sub-module 43 allows the deployment of Value-Added Services (VAS) exploiting the computing resources, such as bandwidth/SLA (Service Level Agreement) management, remote control, remote diagnostic, emergency alarm generation and so on.

The system of the present invention also allows to provide an applicative framework capable of supporting the security needs of a service provider, in terms of segregation and encryption of communications coming from different users, and in terms of log and accounting of the relevant information. In particular, the outdoor module can enable independently encrypted virtual networks for each connection between the users and itself, in such a way that the users can share the same physical connectivity (i.e. the coaxial cable) without reading the other users' signals. This may be implemented by running a networking software (for example the OpenVPN® software) on the second outdoor modem of the outdoor module and the indoor modem of the indoor modules.

Claims

A system (1 ) for distribution of a broadband signal of a mobile radio communication network (2) to at least one subscriber device (3b) located in an indoor environment, said broadband signal comprising a data stream and said system (1 ) including:

an outdoor module (4) configured to receive said broadband signal, extract from it said data stream, encapsulate said data stream into Ethernet data frames and use said Ethernet data frames for modulating at least one carrier signal adapted for being transmitted over a link (8) of said indoor environment together with a further signal; and

an indoor module (5,) connected to said outdoor module (4) via said link (8), said indoor module (5,) being configured to separate said at least one received modulated carrier signal and said received further signal, extract from said at least one received modulated carrier signal said Ethernet data frames and make them available to said at least one subscriber device (3b).

The system (1 ) according to claim 1 , wherein said link (8) is a coaxial cable link.

The system (1 ) according to claim 1 , wherein said link (8) is a power line or a copper pair link.

The system (1 ) according to claim 1 or 2 wherein said outdoor module (4) is connected to a television antenna (6) and said further signal is a digital television signal.

The system (1 ) according to any of the preceding claims, wherein said outdoor module (4) comprises a subscriber identity module for identifying and authenticating a subscriber of said mobile radio communication network (2) or said at least one subscriber device (3b) to said mobile radio communication network (2), said outdoor module (4) being further configured to establish a connection with the mobile radio communication network (2) by means of said subscriber identity module.

6. The system (1 ) according to any of the preceding claims, wherein said outdoor module (4) is further configured to associate with each Ethernet data frame an indoor module identifier indicative of the indoor module (5,) to which the Ethernet data frame are addressed.

7. The system (1 ) according to any of the preceding claims, wherein said outdoor module (4) is further configured to apply an OFDM modulation technique for modulating said at least one carrier signal.

8. The system (1 ) according to claim 7, wherein said outdoor module (4) comprises a band pass filter (47) configured to filter said at least one modulated carrier signal and a high pass filter (48) configured to filter said further signal.

9. The system (1 ) according to claim 8, wherein a frequency of said carrier signal is comprised between about 5 MHz and about 95 MHz and said band pass filter (47) has a bandwidth comprised between about 5 MHz and about 95 MHz.

10. The system (1 ) according to claim 8 or 9, wherein said high pass filter (48) has a cutoff frequency equal to about 130 MHz.

1 1 . The system (1 ) according to any of claims 8 to 10, wherein said outdoor module (4) is further configured to multiplex said at least one filtered modulated carrier signal and said filtered further signal and send a resulting multiplexed signal on the link (8) towards said indoor module (5,).

12. The system (1 ) according to claim 1 1 , wherein said indoor module (5i) comprises a first filter (51 a) configured to filter said resulting multiplexed signal so as to recover said at least one modulated carrier signal, and a second filter (51 b) configured to filter said resulting multiplexed signal so as to recover said further signal.

The system (1 ) according to any of the preceding claims, wherein said indoor module (5,) is further configured to forward said Ethernet data frames to said subscriber device (3b) through a wired connection (9a) or a wireless connection (9b).

The system (1 ) according to any of the preceding claims, wherein said mobile radio communication network (2) is a third or fourth generation mobile radio communication network.

A method for distribution of a broadband signal of a mobile radio communication network (2) to at least one subscriber device (3b) located in an indoor environment, said broadband signal carrying a data stream, said method comprising:

- extracting from said broadband signal said data stream;

- encapsulating said data stream into Ethernet data frames;

- using said Ethernet data frames for modulating at least one carrier signal adapted for being transmitted over a link (8) of said indoor environment together with a further signal;

- separating said at least one modulated carrier signal and said further signal;

- extracting from said at least one modulated carrier signal said Ethernet data frames; and

- making said Ethernet data frames available to said subscriber device (3b).