WO2012155219A1

WO2012155219A1 - Access point for cellular phones

Info

Publication number: WO2012155219A1
Application number: PCT/BR2011/000139
Authority: WO
Inventors: Eduardo Moreno Marques; Ricardo Wiering DE BARROS
Original assignee: YAMAMOTO, José Sindi
Priority date: 2011-05-13
Filing date: 2011-05-13
Publication date: 2012-11-22

Abstract

The present invention is a system comprising an access point (1) as a standalone device or a device connected to a laptop, netbook, smartphone or tablet through an interface such as universal serial bus (USB), with an air interface (5) for cellular phones (2) and another one (6) for the base stations (3) of the mobile cellular network (17), and a set of methods that enable the users to access the telecommunication services across the ADSL/cable modem infrastructure (11) by using their own cellular phones (2) and bypassing the circuit switching (17) and the packet switching (16) mobile cellular networks, but maintaining the facilities of accessing the services across the air interface (6) of the base stations of the mobile cellular network (17). The cellular phones (2), around the access point (1), camp automatically under it and, at the same time, continue virtually camped under the original base station (3) of the mobile cellular network (7). This way, the access to the services across the air interface of the base stations (3) of the mobile cellular network (7) is maintained to the users. Additionally, the system enables the users to perform, with their own cellular phone, without any modification or installation of software application on it, neither any configuration or installation of a new component on the core of the cellular network (17), the access to the services, such as VoIP, message, data and multimedia, across the ADSL/cable modem independently of mobile cellular network operator. The cellular phone (2) of a given technology, e.g. GSM, can be of any model and without any modification or installation of software application on it.

Description

ACCESS POINT FOR CELLULAR PHONES

TECHNICAL FIELD

[001] This invention belongs to the telecommunications field. More specifically, it belongs to the Internet, VoIP (Voice over Internet Protocol) , fixed and mobile cellular network services technical field.

BACKGROUND OF THE INVENTION

[002] The three of the most important worldwide trends in the telecommunications field are the rapid increasing of the number of mobile users, VoIP as an alternative transport method for voice services and the number of broadband Internet connections for both residential and business users. Fixed- mobile convergence, taking the advantage of the three above mentioned trends, appeared as a new service for the mobile operators based on the following main systems that compete each other and with the present invention: VCC (Voice Call Continuity), UMA (Unlicensed Mobile Access), BT Fusion (Bluephone) and femtocell.

[003] In VCC and UMA systems, as standardized by 3GPP (Third Generation Partnership Project, http: //www.3gpp. org/) , it is required the using of dual cellular phone, typically GSM/ iFi or GSM/Bluetooth. The fixed Internet is accessed through a WiFi or Bluetooth access point connected to a broadband interface such as the ADSL. This way, when the users are in the coverage area of the WiFi or Bluetooth access point, they can use their dual mode cellular phone to originate or receive calls, using the ADSL infrastructure of the fixed network instead of the air interface of a base station of the mobile cellular network. In these systems, however, the access point is a component of the mobile cellular network, used as a way to improve or increase its coverage area. Therefore, the operation of the VCC and UMA systems depends on the mobile operator and it does not allow the users to bypass the mobile cellular network using their cellular phone. In order to access the VoIP service through VCC or UMA, it is necessary to install a VoIP client application on the cellular phone. Thus, the basic deficiency of UMA and VCC systems with respect to the system of the present invention are: a) While in the system of this invention the users can use any cellular phones, in the UMA and VCC systems a dual cellular phones are required, which are more expensive and consume much more power so that the duration of the battery charge is significantly reduced, b) The UMA and VCC systems can be used only by mobile cellular operators. On the other hand, the system of the present invention has open interfaces and protocols with the fixed and mobile cellular networks that allow, therefore, the integration with fixed or mobile cellular networks, regardless. Thus, it provides the fixed-mobile convergence advantages for fixed and mobile operators, allowing the users to directly access the services of fixed operators, such as VoIP, as well as the services of mobile operators regardless, simply by using their own cellular phone without any modification or installation of an application on it.

[004] The British Telecom launched the Bluephone. The service, called BT Fusion, used an access point with a Bluetooth or WiFi interface connected to broadband access point like ADSL. The BT Fusion system allowed accessing the fixed network, resembling in this aspect with the present invention. However, as in the case of VCC and UMA system, a deficiency of the BT Fusion system is the need of a cellular phone with WiFi or Bluetooth interface and an application installed on it for VoIP service. Furthermore, in the case of Bluetooth version, it has the limitations of coverage and susceptibility to interference imposed by the Bluetooth interface. In the case of the iFi version, the duration of the battery charge of the cellular phone is significantly reduced. BT Fusion Mobile was withdrawn on April 1, 2009.

[005] A femtocell (http: //www. femtoforum. org/ femto/) is a small cellular base station that can be installed on the users' premises and interconnected with the core of the mobile cellular network using the ADSL infrastructure of the fixed network. For the communication with the cellular phone, it has a standard air interface of the cellular system so that there are no restrictions on the cellular phones. In this aspect, a femtocell is similar to the access point of the present invention. However, a fundamental deficiency of the femtocell, being a component of the mobile cellular network, is that it does not allow the users bypass the mobile cellular network and access the services of the Internet using their cellular phone as allowed by the access point of the present invention. For instance, in order to perform a VoIP call with a femtocell, it is necessary to install a VoIP client on the cellular phone. Besides, in the core of network, the femtocell requires a femtogateway, which is specialized and high cost equipment for mobile cellular network. In the present invention, it is just required a SIP server, which is a very common standard equipment already existent in the VoIP network, or any other standard server such as IAX2.

[006] In the patent application publication no. : US 2008/0244148 Al, it is presented an invention called "VoIP Enabled Femtocell with a USB Transceiver Station". In this invention, the femtocell has an embedded VoIP client in order to perform VoIP calls without installation of any software application on the cellular phone, like in the access point of the present invention. However, the main deficiency of the above mentioned invention in comparison with the present one, is the necessity of an integration of the core of the service provider and mobile operator networks, such as an integration to allow frequency selection for the femtocell carrier, a visitor location register (VLR) implementation on the core of the service provider network integrated with the VLR of the mobile cellular network, in order to allow the mobile call termination (incoming call to the MSISDN (Mobile Subscriber Integrated Services Digital Network) number) when the cellular phone is camped under the femtocell, among others.

[007] In the system of the present invention, the selection of the frequency for its control and traffic carrier is performed independently of the mobile cellular network, as well as all other functions. Even when the cellular phone is camped under the access point, the mobile termination calls are automatically performed across the air interface of base station of the mobile cellular network, without any implementation of a new component, configuration or modification in the core of the service provider or mobile cellular network.

[008] One more advantage of the present invention with respect to femtocell or system based on femtocell approach, it is related with the call or message origination. In the present invention, even when the cellular phone is camped on the access point, the users has the option to originate calls and messages as well as to access the Internet, across the ADSL/cable modem infrastructure, bypassing the mobile cellular network, or across the air interface of a base station of the mobile cellular network. Therefore, the user can always select the output to the network that results more economical or convenient to him. Regarding the femtocells, another deficiency refers to the necessity of using high precision oscillators which are a high cost electronic component. In the present invention, a low cost oscillator equivalent to those for cellular phones can be used, thanks to a method of automatic frequency correction of the local oscillator of the access point based on the RF signal received from the base station of mobile cellular network, as performed by the cellular phones.

[009] The above context shows that all the current systems that compete with the present invention are for the mobile operators. The fixed operator is not able to use those systems independently of the mobile operator. Therefore, even with the appearance of these systems, the users will continue to use their cellular phone only to access the services of the mobile operators, Internet service providers (ISP) and services such as VoIP to VoIP calls, under the control of mobile operator or across the mobile cellular network. In order to access the services of fixed operators across the infrastructure such as the ADSL and cable modem, independently of mobile operators and bypassing their network, the users need to use another terminal. The possibility of using the cellular phone to access the services of fixed operator and mobile operator, independently, across the fixed infrastructure (such as ADSL and cable modem) and the air interface of the base station, respectively, it would increase the level of competition between the fixed and mobile operators, create new services and bring more benefits to the users.

[010] Therefore, there is a need for a system that allows the users to use their own cellular phone to access the services of mobile cellular operator and fixed operator, independently, operates under the control of mobile operator or fixed operator, or independently of both just controlled by the users. Further, there is a need that this system can be used at home, office or in a nomadic way when the users are travelling. Such system could operate with low power, using the same frequency band of mobile services or out band when possible, and have features to mitigate interferences on the mobile cellular network and other systems.

SUMMARY OF THE INVENTION

[Oil] The invention described in this report is a system comprising a cellular access point (AP) , as a standalone device or a device connected to a laptop, netbook, smartphone or tablet through an interface such as universal serial bus (USB) , and a set of methods that allows the telephony users to access the services of the Internet, such as VoIP, short message services (SMS) and data/multimedia, by using their own cellular phone and bypassing the mobile cellular network (Circuit Switching or Packet Switching network) , across the ADSL (Asymmetric Digital Subscriber Line) /cable modem infrastructure, but keeping the existent facilities to access the services of the mobile operator across the air interface of the base station of the cellular network. The cellular phone of a given technology, e.g. GSM, 3G-WCDMA (Third Generation Wideband Code Division Multiple Access), etc., can be of any model and there is no necessity of any modification or installation of software application on it.

[012] The AP has two cellular standard air interfaces: cellular base station side interface and cellular phone side interface, both integrated with an IP router into a small standalone device for residential and small office/home office applications. Alternatively, these two standard air interfaces can be integrated into an device connected to a personal computer, like laptop or netbook, smartphone or tablet through an interface such as USB, for nomadic application when the users are travelling.

[013] The AP has a particular coverage area (cell) where the cellular phones camp under it. When the cellular phones are camped under the AP, it allows the users to access the services of Internet, bypassing the mobile cellular network, across the ADSL/cable modem broadband infrastructure. This way, the services of the Internet are accessed across the ADSL/cable modem broadband interface, as performed by a VoIP ATA (Analog Telephone Adapter) .

[014] The access to the services of mobile operator across the air interface of the base station of the cellular network, if it is present, is maintained to the users via the standard cellular phone air interface of the AP. This way, the access to the services of the mobile cellular network across the air interface of the base station, such as the mobile call origination, mobile call termination to a MSISDN number, are performed via the cellular phone interface of the AP.

[015] Previously, the users can themselves register their cellular phones on the AP through a Simcard interface, so that when the cellular phones with registered simcard enter into the coverage area (cell) of the AP, they automatically camp under it. Alternatively, the simcard of the users can be registered remotely by the service provider (VoIP operator, fixed or mobile operator) .

[016] In the core of the network, the AP is integrated with a VoIP server or PABX, e.g. SIP server, SIP PABX like Asterisk, etc. When the AP is integrated with a PABX, the cellular phones, camped under the AP, operate as a wireless extension of the PABX.

[017] According the above description, the AP of the present invention has 4 interfaces: i) Broad band interface: it is a interface to the Internet across ADSL or a cable modem; ii) Cellular phone interface: it is a wireless interface of the same standard of the cellular phones for data control or signaling information exchange (not for voice or data/multimedia traffic) with the server base station of the W 201

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mobile cellular network; iii) Base station interface: it is a wireless interface of the same standard of the base station of the mobile cellular network for communication with the cellular phones, iv) Simcard interface: it is an optional interface for the user to register the IMSI (International Mobile Subscriber Identity) in a list of allowed IMSI of the AP, by inserting the simcard into the slot of the interface. Also, it is used for the generation of the authentication and ciphering parameters (SRES and kc in GSM system) when the simcard is inserted into the slot of the interface for it.

[018] While the cellular phone interface allows the AP to behave like a cellular phone for the base station of the mobile cellular network, the base station interface allows the AP to behave like a cellular base station with a particular coverage area. Thus, when a cellular phone enters into the coverage area of the AP, it automatically camps under the AP.

[019] In the present invention, a method comprising a set of processes maintains the registration of the cellular phone on the mobile cellular network when it camps under the AP. If the cellular coverage is present and the cellular phone is not previously registered on the mobile cellular network, it is authenticated and registered on the mobile cellular network through a set of processes performed by the AP during the camping of the cellular phone under it.

[020] The AP, by using its cellular phone interface, is able to provide a bridge between the cellular phone camped under it and the server base station of the mobile cellular network. This way, the signaling information sent by cellular phone to the AP is relayed to the server base station of the mobile cellular network and vice versa. Thus, even when the cellular phone is camped under the AP, a mobile terminated call (MTC: incoming call to the MSISDN number of the cellular phone camped under the AP) is completed as the cellular phone was W 201

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camped under the base station of the mobile cellular network. Therefore, no configuration or modification on the core of mobile cellular network, neither an update of the cellular phone location on the VLR (Visitor Location Register) /HLR (Home Location Register) data bases are necessary for MTC even when the cellular phone is camped under the AP of the present invention .

[021] When the cellular phone is camped under the AP, the user can have a VoIP number in addition to the MSISDN number. Therefore, an incoming VoIP calls (mobile terminated VoIP calls - MTVC) to the VoIP number of the user can be performed across the Internet via the broadband ADSL/cable modem interface, by passing the mobile cellular network at the termination. Additionally, when the cellular phone is camped under the AP, the user can originates VoIP calls (mobile originated VoIP calls - MOVC) , across the Internet via the broadband interface (ADSL/cable modem) . In both cases, mobile cellular network coverage in the area around the AP location is not required. Alternatively, if the area around the AP is covered by the mobile cellular network, then a mobile originated call (MOC) or a mobile terminated call (MTC) can be performed across the air interface of the mobile cellular network, by using the cellular phone interface of the AP for signaling exchange with the server base station of the mobile cellular network.

[022] Even when the frequency assigned to the control carrier of the AP does not belong to the list of neighbor cells of the server base station, or when it is out of the frequency bands of the mobile operators, the AP is able to force the cellular phones automatically camp under it. This way, depending on the regulation of each country, the AP can operate in an unlicensed frequency band that is a sub-band of the cellular system frequency band. This feature of the AP allows its utilization by a fixed network operator that does not have mobile licensed frequency band or directly by the users independently of any network operator.

[023] Regarding the frequency precision of the local oscillator of the AP, a low cost oscillator equivalent to those for cellular phones can be used, thanks to a method of automatic frequency correction of the local oscillator based on the RF signal received from the server base station via the cellular phone air interface of the AP.

[024] Thus, the system of the present invention has the following objectives in relation to cellular phones around the coverage area of AP:

[025] a) Automatic camping and automatic reselection of AP cell even when operating out of licensed frequency band of mobile operators.

[026] b) Automatic authentication and registration of the cellular phones in the mobile cellular network even when camped under the AP.

[027] c) OVC (Mobile Originated VoIP Call) to fixed, cellular or IP telephone, through the Internet as VoIP session, via the ADSL/cable modem broadband infrastructure as if the VoIP call was originated from a VoIP soft phone on the computer, VoIP phone or ATA connected to the Internet.

[028] d) MOC (Mobile Originated Call), as an option feature for the user, across the air interface of the mobile cellular network by using the cellular phone air interface of the AP for signaling information exchange with the server base station, as the call was originated from a cellular phone camped under the base station of the mobile cellular network.

[029] e) Mobile terminated call (MTC) (incoming calls to the MSISDN number) across the air interface of the mobile cellular network by using the cellular phone air interface of the AP for signaling information exchange with the server base station, without any modification or installation of a new element in the core of service provider or mobile cellular network, i.e., independently of the mobile operator.

[030] f) Mobile Terminated VoIP Call (MTVC) to the user fixed number or VoIP number through the Internet as VoIP session, via the ADSL/cable modem broadband interface of the AP.

[031] g) Mobile originated (MO) /Mobile terminated (MT) SMS through an SMS center in the Internet via the ADSL/cable modem broadband interface.

[032] h) Mobile originated (MO) SMS across the air interface of the mobile cellular network by using the cellular phone air interface of the AP for signaling information exchange with the server base station, as an option for the user .

[033] i) Mobile terminated (MT) SMS across the air interface of the mobile cellular network by using the cellular phone air interface of the AP for signaling information exchange with the server base station, without any modification or configuration in the core of mobile cellular network.

[034] j) Transmission and receiving of data/multimedia, bypassing the mobile cellular network, via the ADSL/cable modem broadband interface.

[035] k) Transmission and receiving of data/multimedia across the air interface of the base station of the mobile cellular network by using the cellular phone interface of the AP for signaling information exchange with the server base station, as an option for the user.

[036] 1) Wireless extension of a PABX.

[037] m) Frequency correction of the local oscillator of the AP.

BRIEF DESCRIPTION OF THE DRAWINGS W 201

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[038] The invention itself, as well as the preferred mode of using, further objects and advantages thereof is best understood by reference to the following detailed description of various exemplary embodiments when read in conjunction with the accompanying drawings, wherein like numerals denote like elements :

[039] FIG.l shows the concept of the access point system of the present invention.

[040] FIG.2 shows the access point of the present invention in the context of fixed and mobile cellular networks and integrated with the core of the fixed network.

[041] FIG.3 shows the core of the mobile cellular network when the access point of the present invention is integrated through it.

[042] FIG. shows a system where the cellular phones are wireless extension of a PABX by using the access point of the present invention.

[043] FIG.5 shows the composition of the access point of the present invention.

[044] FIG.6 shows the details of an exemplary embodiment of the access point of the present invention as a standalone device .

[045] FIG.7 shows the details of an exemplary embodiment of the access point of the present invention as an USB device connected to a personal computer.

[046] FIG.8 presents a flowchart of the booting processes of the access point of the present invention.

[047] FIG.9 presents the messages flow during the camping process of the cellular phone under the access point of the present invention.

[048] FIG.10 presents the messages flow during the mobile terminated call across the air interface of the server radio station. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

[049] The exemplary embodiments of the present invention are described for GSM/GPRS/EDGE cellular system technology, but the invention applies to other tecnologies such as CDMA (http://www.cdg.org/), 3G- CDMA/HSPA as well as 4-G cellular system such as LTE (http: //www. gsmworld. com/technology/3gsm/ ) .

[050] Concept of the system: Fig. 1 shows the system concept of the present invention, where: (1) is a access point (AP) ; (2) is a cellular phone camped under the cell of AP (1); (3) is the server base station of the mobile cellular network. The AP (1) consists of 4 interfaces:

[051] a) Broad Band Interface (BBI) (4): it is a broadband interface to the Internet via ADSL or a cable modem infrastructure. BBI (4) is used to access the services of Internet, bypassing the mobile cellular network and allowing functions via ADSL or cable modem infrastructure such as:

Mobile originated VoIP call (MOVC) .

Mobile terminated VoIP call (MTVC) .

Mobile origination of SMS.

Mobile termination of SMS.

Transmission and receiving of data/multimedia.

[052] b) Cellular phone Interface (CPI) (6): it is a wireless interface of the same standard of the cellular phones for control data or signaling information exchange between the server base station (3) and the cellular phone (2) . Fl is the frequency of the control carrier of the server base station (3). Fl ^' is the frequency assigned to the carrier of the CPI (6) . The CPI (6) is used when the users want to access the services of the mobile cellular network across the air interface of the server base station (3) . The access is performed in conjunction with the base station interface (BSI) (5) by enabling a signaling information exchange between the cellular phone (2) and the server base station (3) . The access to all the existent services across the air interface of the mobile cellular network is maintained to the users by using the

CPI (6) , such as :

Mobile originated call (MOC) .

Mobile terminated call (MTC) .

Mobile origination of SMS.

Mobile termination of SMS.

Transmission and receiving of data/multimedia.

[053] The AP (1) provides inside it a bridge (7) between the CPI (6) and BSI (5) in order to perform a transparent signaling exchange between the cellular phone (2) camped under the AP (1) and the server base station (3) of the mobile cellular network. The CPI (6) is used only for signaling information exchange on common control channel up to the designation of a dedicated control channel. After the designation of the dedicated control channel, the direct air interface (8) , between the cellular phone (2) and the server base station (3), is used.

[054] Also, the CPI (6) is used for: a) Detection of the carrier of the server base station of the mobile cellular network; b) Frequency correction of the local oscillator of the AP; c) Synchronization of the AP (1) with the server base station (3) ; d) Reading of the neighbor cell list from the control carrier of the server base station (3) and selection of the frequencies for the control and traffic carrier as well as for the auxiliary control carrier of AP (1) .

[055] c) Base station Interface (BSI) (5) : it is a wireless interface of the same standard of the base station of the mobile cellular network for communication with the cellular phones. F2 is the frequency of the control and traffic carrier of the AP (1), known as broadcast control channel (BCCH) carrier in the GSM technology. F2 ' is the frequency of the cellular phone (2) carrier. F5 is the frequency of an auxiliary control carrier of the AP (1) that is used when the F2 and F2 ' frequencies are out of the frequency band of the mobile operator. BSI (5) and the CPI (6) are interconnected, inside the AP (1), through a bridge (7) in order to enable a transparent signaling exchange between the cellular phone (2), camped under the AP (1), and the server base station (3). All the functionalities described for CPI (6) and BBI (4) depends on BSI (5) . Therefore, BSI (5) is used to access the services of the fixed network and mobile cellular network. In the case of accessing the services of fixed network, BSI (5) is used for signaling exchange, voice, SMS and data/multimedia traffic between the cellular phone (2) and the AP (1) . In the case of accessing the services of mobile cellular network across its air interface, the BSI (5) is used only during the signaling exchange on common control channel up to the designation of a dedicated control channel on the air interface of the server base station (3) . After the designation of a dedicated control channel, the direct air interface (8) between the cellular phone (2) and the server base station (3) is used.

[056] Also, BSI (5) is used for the following functions: Selection/reselection of the cell of the AP (1) by the cellular phones around it, even when the AP (1) operates out of band of the mobile cellular operator.

Automatic camping of the cellular phones under the cell of the AP (1), even when it operates out of band of the mobile cellular operator.

[057] d) Simcard Interface (SCI) (35): the AP (1) of the present invention allows the creation of a list of IMSI that are allowed to camp under it. This list prevents that any cellular phone around the AP (1) camps under it. The list is created by reading the IMSI from the user Simcard through the SCI (35) . Also, it is used for the generation of the authentication and ciphering parameters. For GSM system for instance, a number of a set of three parameters: SRES (Signed RESponse) , RAND (authentication challenge random number) and kc, is generated for each IMSI and saved to be used for authentication and ciphering purpose. This interface is not necessary if the list of the allowed users and the authentication and ciphering parameters are provided remotely by the mobile operator.

[058] Depending on the regulation of each country, some frequency sub-bands of the cellular system technology, GSM for instance, belong to a non-licensed frequency band or are out of frequency band for the mobile operator. When the AP (1) is operating in such frequency bands, an auxiliary control carrier is transmitted by the BSI (5) in order to allow the automatic selection/reselection of the cell of the AP (1) by the cellular phone (2) and its automatic camping under the cell of the AP

(1) . In the exemplary embodiment shown in fig.l, the auxiliary control carrier is transmitted using the frequency F5. F5 is the frequency of the control carrier of a distant neighbor base station (10) with the lowest power around the AP (1) . A cell neighbor list with frequencies in the non-licensed band or. out of frequency band of the mobile operator is transmitted to the cellular phones around the AP (1) through the auxiliary control carrier in the frequency F5. This way, since the frequency F5 of the auxiliary control carrier belongs to the cell neighbor list of the server base station (3) and it has a better signal quality than others control carriers around, the cellular phone

(2) reads the neighbor cell list of the auxiliary control carrier F5. This neighbor cell list consists of frequencies, for instance, F2 among others, in the non-licensed band. When the cellular phone comes into the coverage of the auxiliary control carrier, it requests access through the common control channel in the uplink direction to the AP (1) . As there is no response to the access requested, the cellular phone selects another carrier control, now in the non-licensed frequency band, F2 for instance, that it read from the cell neighbor list sent on the auxiliary control carrier in the frequency F5. The cellular phone requests access through the common channel in the uplink frequency F2 ' . Then it receives a response to the access request and camps under the AP (1) .

[059] Integration with the core of the network: the AP (1) can be integrated with the core of the fixed network or mobile cellular network. The integration with the core of the fixed network can be done by interconnecting a media gateway ( Gw) (18) to the switching center (15) of the Public Switching Telephony Network (PSTN) (12) as shown in fig.2.

[060] Despite of the AP (1) is integrated with the fixed network (12) , the users can continue accessing the services of the mobile cellular networks (17) and (16) across the air interfaces (6) and (8), in addition to the services of fixed network (12) and (13) across the ADSL/cable modem infrastructure (11), by using their cellular phone (2), even when it is camped under the AP (1) .

[061] The components of the system of the present invention when the AP (1) is integrated through the fixed networks (12) and (13) can be described as follows:

[062] - AP (1) connected with the core of the PSTN (12) via ADSL/modem cable (11) and communicating with the cellular phone (2) and server base station (3) through the standard cellular wireless interfaces (5) and (6), respectively;

[063] - Cellular phone (2) camped under the AP (1) and communicates with the AP (1) and the server base station (3) through the standard cellular wireless interfaces (5) and (8), respectively. [064] - PSTN (12) and its switching center (15) and fixed telephone (14) components.

[065] - Internet (13) and its following components: IP router (19), VoIP server or PABX (21), IP phone (20) and Short Message Service Centre (SMSC) (22) . In this preferred exemplary embodiment, a SIP server or SIP PABX are used, but others standard servers and PABXs, such as IAX2, are applicable.

[066] - Circuit Switched (CS) Cellular Network (17) and its following components: BSC (Base Station Controller) /RNC (Radio Network Controller) (20) and Circuit Switched Media Gateway (CS-MGw) (24).

[067] .- Packet Switched (PS) Mobile Cellular Network (26) and its following components: Service GPRS Support Node (SGSN) (23) and Gateway GPRS Support Node (GGSN) (25) .

[068] - MGw (Media Gateway) (18) : it is an interface for the media conversion and transmission between the switching center (15) of PSTN (12) and the Internet (13) . The MGw (18) allows the interoperation of the VoIP solution on the Internet with a circuit switched network. On the Internet, protocols such as SIP can be used for the signaling between the VoIP client, embedded on the AP (1), and the VoIP server or PABX (21) . In this preferred exemplary of embodiment of the invention, the SIP protocol is used but the invention applies to other protocols such as the IAX2, MGCP or a proprietary VoIP protocols for the communication with the service provider. Also, in this preferred exemplary of embodiment of the invention, the RTP (Real Time Protocol) /RTCP (Real Time Control Protocol) is used to carry the digital encoded voice signal (voice media) . On the side of the circuit switched network, an El interface is used to carry the digital encoded voice signal. The SS7 (Signaling System 7) is used for switched circuit signaling.

[069] - ADSL or cable modem (11) infrastructure. [070] - DSLAM (Digital Subscriber Line Access Multiplexer) /CMTS (Cable Modem Termination System) (27): it is the termination of ADSL/cable modem on the side of fixed network core.

[071] - Server Base station (SBS) (3) controlled by the BSC/RNC (20) and communicates with the AP (1) and the cellular phone (2) trough the cellular standard wireless interfaces (6) and (8), respectively.

[072] - BSC (Base Station Controller) /RNC (Radio Network Controller) : BSC and the RNC are controllers of base stations. In the GSM network, the base station controller is called BSC. In the 3G-WCDMA network, the controller is called RNC.

[073] - CS-MGw (Circuit Switched Media Gateway) (24) : it is an interface for the media between the BSC/RNC (20) and the PSTN (12) .

[074] - SMSC (Short Message Service Centre) . It is a SMS server of fixed operator (22) or of mobile network operator (26) .

[075] - SGSN (Service GPRS Support Node) (23) : it is a packet router of the packet cellular network (26) . Also, it is responsible for the mobility management, authentication and accounting in the packet mobile cellular network.

[076] - GGSN (Gateway GPRS Support Node) (25) : component of the mobile cellular network that interfaces the packet switched mobile cellular network (26) with the Internet (13) .

[077] The integration of the AP (1) with the core of the mobile cellular network is shown in fig.3. It is done by interconnecting the media gateway (MGw) (18). with the circuit switched media gateway (CS-MGw) (24) of the mobile cellular network. The network components are the same used in the integration of the AP (1) with the fixed network as shown in fig.2. [078] Cellular phone as a Wireless Extension of a PABX: the AP of the present invention can be integrated with a PABX. In this system, each cellular phone, camped in the AP, becomes a wireless extension of the PABX. The integration of 2 APs, (1) and (29), with a PABX (21) is shown in fig. 4. The cellular phones (2) and (28), camped on the AP (1), become wireless extensions of the PABX (21) . Similarly, the AP (29) integrates with the same PABX (21) and the cellular phones (30) and (31) camped under it become wireless extension of the same PABX (21) . Protocols such as SIP and RTP/RTCP can be used to establish the calls and for the media transmission, respectively. The user of each cellular phone is registered in the PABX (21) . Thus, calls from a cellular phone camped on the AP (1) to another cellular phone also camped in the same AP (1) or another AP (29) , consist of VoIP sessions and behave like a extension to extension calls. Thus, the users of cellular phone keep all the facilities for origination and termination of calls across the air interface of the mobile cellular network and, moreover, may use the cellular phones as wireless extensions of the PABX (21) . Additionally, if the PABX (21) is integrated with the core of each type of network with specific outputs, the user can originate external calls through the PABX (21) which, in turn, choose one of 3 outputs for the external network, one that is more economical for the user, as follows:

[079] a) Output via fixed Internet (34) : the output via the fixed Internet is chosen when the destination is a VoIP number, or when it is a long distance call to a fixed or cellular phone. In the last case, the PABX (21) redirects the call to another PABX located in the area of the called user so that it performs the original call as being a local call origination. [080] b) Output via the air interface of the mobile cellular network, by using cellular modems (32) : when the destination is a cellular number (MSISDN number) .

[081] c) Output via El interface (33) : when the destination is a user number of PSTN.

[082] Composition of the AP: the AP of the present invention is composed by 3 modules as shown in fig. 5:

[083] a) Cellular Phone Adapter (CPA) (38) : it performs the standard air interface functions of a base station, so that the cellular phones, around the AP (1), select its cell and camp under it. The physical layer and the layers of the protocol stack of the network side for voice and data/multimedia services are performed by CPA module (38) . It performs functions of a BSS (Base Station Subsystem) /RAN (Radio Access Network) that are essentials for cell selection/reselection, camping, mobile call origination/termination, and mobile SMS origination/termination. The BSS is the set formed by the base station and the BSC (Base Station Controller) in the case of GSM system. The RAN is the set formed by the base station and the RNC (Radio Network Controller) for the 3G-WCDMA system. In case of fixed Internet access for data/multimedia services, the CPA module (38) performs the essential features of the BSS or RAN entities, SGSN and GGSN of the packet cellular network. Also, the timing and frame synchronization with the server base station (3) is performed by this module in conjunction with the cellular network access (CNA) module (39) . The CPA (5) module communicates with the cellular phone via the standard air interface (5) for signaling information exchange and data/voice traffic transmission/reception.

[084] b) Cellular Network Access (CNA) (39): it performs the standard air interface functions of the cellular phone side allowing the AP (1) to receive/transmit the signaling information, such as paging and response to paging messages, from/to the server base station (3) of the mobile cellular network, across the air interface (6) . The CNA module (39) , by using an internal bridge (7), relays the signaling information received from the server base station (3) to the CPA module

(38) . The CPA module (38) transmits the received signaling information to the cellular phones (2) camped under it. Further, the CPA module (38) relays the signal information received from the cellular phones (2) to the CNA module (39) across the bridge (7) . Also, the CNA module (39) is responsible for: a) Detection of the carrier of the server base station (3) of the cellular phone (2) ; b) Frequency correction of the local oscillator of the AP (1) ; c) Timing synchronization of the AP (1) with the server base station (3) ; d) Reading of the cell neighbor list of the server base station (3) and selection of the frequency for the AP (1) control and traffic carrier. By reading the cell neighbor list of the server base station (3) , the CNA module (39) selects a frequency for the control and traffic carrier (or auxiliary control carrier) . The selected frequency belongs to the cell neighbor list of the server base station in order to enable the cellular phones around the AP (1) to camp automatically under it. Therefore, the CNA module

(39) sweeps all the frequencies of the cell neighbor list and selects the one with the lowest power for the control and traffic carrier or auxiliary control carrier of the AP (1) .

[85] c) Broadband Access (BBA) (40) : this module performs the functions of a VoIP client, SMS client, IP layers stack and, optionally, it can perform the IP router functions including quality of services (QoS) for VoIP service. The VoIP client establishes the call using a protocol such as SIP, with the VoIP server or PABX (21) and performs the transmission/reception of the voice media (encoded voice signal) using a protocol such as the RTP/RTCP. The SMS client uses a protocol such as the SMPP (Short Message Peer to Peer, http: //smsforum. net/ ), to communicate with the SMSC (22). At the AP (1) side, the voice signal is encoded and decoded by the cellular phone. At the core of the network, the voice signal is encoded and decoded by the MGw (18) . The user of the cellular phone (2), when camped under the AP (1), is registered on the VoIP server or PBX (21) . Similarly, the user of the cellular phone, when camped under the AP (1), registered on the SMSC (22). Also, this module includes an implementation of the Ethernet interface BBI (4) .

[086] An exemplary detailed embodiment of the standalone device (1) of the present invention is shown in the fig.6. A digital signal processor (DSP) and controller are integrated in one digital baseband processor (42) . The digital baseband processor (42) is used to perform the processes of the PHY layer of the CPA (38) and CNA (39) modules. The processes of the PHY layer of the CNA module (39) are the same standard processes of the PHY layer of the cellular phone side. Similarly, the processes of the PHY layer of the CPA module (38) are the same standard processes of the PHY layer of the mobile cellular network side. Considering the state of art of the current commercial DSPs and controllers, the same digital baseband processor (42) is used to perform the processes of the protocol stack layers of the CPA module (38) which are the same standard processes of the protocol stack layers of the mobile cellular network side. Also, the same digital baseband processor (42) is used to implement the VoIP and SMS clients as well as the IP stack layers of the BBA module (40) . Optionally, an IP router is implemented as part of the BBA module (40) .

[087] In this exemplary embodiment, three analog baseband processors, (49), (50) and (51), are used in the CPA module (38) . The analog baseband processor (49) is used to demodulate the radio frequency (RF) signal received from the cellular phone (2) and to convert the baseband analog symbol of control and traffic data to the digital data format. The analog baseband processor (50) is used to convert the traffic and control digital data into analog symbols that modulate the RF signal generating the control and traffic carrier of the CPA module (38) . The analog baseband processor (51) is drawn in dashed line to indicate that it shall be enabled only if the device will operate out of the frequency band of the mobile operator, e.g. in non-licensed frequency, depending on the regulation rules of each country. In this case, the analog baseband processor (51) is used to convert the control digital data into analog symbols that modulate the RF signal generating an auxiliary control carrier of the device. The same analog baseband processor (48) is used to perform the modulation/demodulation (MODEM) processes, analog to digital conversion (ADC) of demodulated I&Q signal components, digital to analog conversion (DAC) of the modulated I&Q signal components of the CNA module (39) . The exemplary embodiment of the standalone device uses a FLASH memory (44) and a SDRAM (43) as the program memory and data memory, respectively. A power management module (PMM) (45) is used for DC power control.

[088] An exemplary detailed embodiment of the USB device of the present invention is shown in the fig.7. In this embodiment, the processes of the CPA module (38) are distributed between the CPU of the personal computer (PC) (54), digital baseband processor (42) , analog baseband processors (49), (50) and (51). This distributed processing of the CPA module (38) allows the using of a less complex digital baseband processor than the one used to implement the standalone device. The communication between the digital baseband processor (42) and the CPU of the PC (54) is performed through an USB interface (53) . The USB controller (52) establishes and manages the data link with the PC (54), and provides enough bandwidth for the USB device (55) to handle multiple simultaneous calls, data and multimedia accessing. The USB controller (52) in fig. 7 is shown outside the digital baseband processor but, depending of the processor, it can be inside the processor reducing the complexity and the cost of components of the USB device (55) . The power to the USB device (55) is obtained from the physical USB connection (53) to the PC which allows additional complexity and component cost reducing.

[089] Set of processes of the system: an exemplary embodiment of the processes involved in the present invention is described for the GSM system. The processes are classified as: booting processes, cell selection/reselection, camping, registration on the VLR/HLR and services access processes.

[090] a) The booting processes:

A flowchart of the booting process is shown in fig. 8. It consists of a set of 8 sub-processes each with specific functions described as follows:

[091] Sub-process 1 (56) : Detection of the control carrier of the server base station (SBS) : the first booting sub-process is the detection of the carrier of the server base station. The detection is performed by the CNA module (39) that sweeps all the frequencies within the frequency band of the mobile operator and measures the power of the carrier at each frequency. The carrier with the highest power is selected as being the control carrier of the server base station of the mobile cellular network in the area around AP (1) .

[092] Sub-process 2 (57) : Local oscillator frequency correction: the second booting sub-process is the minimization of the frequency drift of local oscillator relative to the frequency of the control carrier of the server base station (3) . In case of GSM technology, the frequency of local oscillator is corrected by the CNA module (39) using the property of the FCCH (Frequency Correction Channel) where the incoming string of data results in a frequency equal to ¾ of GSM symbol rate.

[093] Sub-processes 3 (58) : Synchronization of CNA module

(39) with the server base station (SBS) : the synchronization with the server base station (3) is performed by the CNA module

(39) in conjunction with the CPA module (38), through the acquisition of FCC (Frequency Correction Channel) and SCH

(Synchronization Channel) logical channels by the CNA module

(39) , for this purpose transmitted on the BCCH (Broadcast Control Channel) carrier of the server base station (3) , in GSM system. The FCCH acquisition provides timing synchronization of the CNA module (38) with the server base station (3) . The SCH acquisition is followed by the reading of synchronism information (62). The synchronism information (62), such as the TDMA frame number, is also provided, across the bridge (7), to the sub-process 4 (63) of the CPA module (38) in order to enable it to synchronize with the server base station (3) too. This way, the both modules, CNA (39) and CPA (38) become synchronized with the server base station (3) of the mobile cellular network.

[094] Sub-process 4 (63) : Synchronization of CPA module

(39) with the server base station (SBS): the CPA module (38) synchronizes with the server base station (3) based on the timing acquired by the CNA module (39) and the synchronism information received from CNA module (39) across the bridge

(7). This way, the CPA module (38), CNA module (39) and the cell phone (2) become synchronized with the server base station

(3) .

[095] Sub-process 5 (59) : Reading of the cell neighbor list of the server base station (SBS) : after the CNA module (39) is synchronized with the server base station (3), it is able to read the messages from the logical channel BCCH (Broadcast Control Channel) . The message containing the neighbor cell list is read and a list of ARFCN (Absolute Radio Frequency Channel number) (68) of the neighbor cells is sent: a) to the process 6 (61) if the API (1) will operate in band of the frequencies of the mobile operator; b) to the process 8 (60) , if the AP (1) will operate out of band of the frequencies of the mobile operator.

[096] Sub-process 6 (61): Selection of the ARFCN for the control and traffic channel: this sub-process selects the frequency of control and traffic carrier of the AP (1) . If the AP (1) will operate in band of the mobile operator, the frequency of the control carrier of the neighbor cell with the lowest power is reused for the control and traffic carrier of the AP (1) . Therefore, in this case, this process sweeps all the frequencies of the ARFCN list (68), received from the process 5 (59) , and measures the power of the carrier at each frequency. The ARFCN (65) of the carrier with the lowest measured power is sent to the process 7 (67), where it is reused to generate the control and traffic carrier of the AP (1) . If the AP (1) will operate out of band of the mobile operator, this process sweeps all the frequencies in the defined sub-bands out of the band of the mobile operator, and selects the ARFCN with the lowest power to be send to the process 7 (67) .

[097] Sub-process 7 (67) : Generation of the control and traffic carrier: this sub-process receives the ARFCN (65) from the process 6 (61) and generates the control and traffic carrier of the AP (1) which behaves, this way, like a server base station to the cellular phones around it.

[98] Sub-process 8 (60): Selection of the ARFCN for the auxiliary control carrier of the AP: this sub-process is used to select the frequency for the auxiliary control carrier of the AP (1) when it is operating out of the frequency band of the mobile operator. In this case, the frequency of the control carrier of the neighbor cell with the lowest power is reused for the auxiliary control carrier. Therefore, this process sweeps all the frequencies of the ARFCN list, received from the process 5 (59) , and measures the power of the carrier at each frequency. The ARFCN of the carrier with the lowest measured power is sent to the process 9 (66), where it is reused to generate the auxiliary control carrier of the AP (1) . Also, this sub-process send a list of ARFCNs out of frequency band of mobile operator to the sub-process 6 (61) which selects an ARFCN out of band for the control and traffic carrier of AP (1) .

[99] Sub-process 9 (66): Generation of the auxiliary control carrier: this sub-process receives the ARFCN (64) from the process 8 (60), and generates the auxiliary control carrier to the cellular phones around the AP (1) .

[100] b) Cell selection/reselection

The AP (1) of the present invention will be installed in indoor environment, so that the cellular phones are close to it. Thus, the quality of the control carrier of the AP (1) is better than that of the base station of the mobile cellular network. Furthermore, the cell selection/reselection parameters of the control carrier of the AP (1) are set up favor to the selection of its cell. This way, the cellular phone selects the AP (1) as the better server than any base station of the mobile cellular network in the indoor area around it. The coverage area of the AP (1) depends on the configuration of the parameter values for cell selection/reselection in the layer 3 of the protocol stack, and the power emitted by the RF front end.

[101] If the AP (1) is operating out of the frequency band of the mobile operator, the cellular phones selects the control and traffic carrier of the AP (1) in two steps: 1) First, the cellular phone selects or reselects the auxiliary control carrier, reads the neighbor cell list and request access through the common control channel on this carrier; 2) The AP (1) does not respond to the access requested by the cellular phone. Then, since there is no response to the access requested, the cellular phone selects a new carrier control that has the best quality among the cell neighbor list sent on the auxiliary control carrier. Since the ARFCNs of the cell neighbor list on the auxiliary carrier are out of band of the frequency band of the mobile operator, the new control and traffic carrier selected for the AP (1) is out of frequency band of mobile operator.

[102] c) Camping

The AP (1) of the present invention allows the creation of a list of I SI that are enabled to camp under it. This list prevents that any cellular phone around the AP (1) camps under it. The list of authorized IMSI is created by reading the IMSI (International Mobile Subscriber Identity) from the SimCard of the user. For each IMSI, an association is made with the fixed number of user and/or VoIP number of the user. Additionally, for each IMSI in the list is associated a list of parameters set: SRES and Kc, associated with respective RAND, in case of GSM system. When there is a camping or service access attempting of a user with authorized IMSI, a RAND from the list of parameters set associated with the IMSI is chosen randomly and sent to the cellular phone. This way, only the cellular phones with the IMSI registered in the list of authorized IMSI are able to be authenticated and camp under the AP (1) to use it. Also, the kc parameter is used for the ciphering of the control and data information if it is required.

[103] An exemplary embodiment of messages flow diagram during a GSM cellular phone camping process under the AP (1) is shown in fig.9. In this figure, F2 of the pair of frequencies (69) is the frequency selected by the CNA module (39) for the W

30

control and traffic carrier (5) of the AP (1) . F2' of the pair of frequencies (69) is the frequency of the carrier of the cellular phone (2) in the uplink. After the cellular phone (2) selected the control- carrier F2, it requests access to the AP

(1) by sending the channel request message (70) through the common control channel on the uplink carrier in the frequency F2' . Then, if the user belongs to the list of allowed users, the sequence of messages are exchanged between the cellular phone (2) and the AP (1) until the channel release message (79) that completes the camping process. If the user does not belong to the list of allowed users, the location update request message (72) is rejected with a cause that forces the cellular phone to select another control carrier and not try to re- select the control and traffic carrier of the AP (1) again. Since for the camping process of the present invention, it is essential that the cellular phone sends the location update request message (72), the LAC (Location Area Code) sent on the control carrier of the VoIP is always different from the LAC sent on the control carrier of the server base station.

[104] d) Registration on the VLR/HLR

The registration of the user on the Visitor Location Register (VLR) /Home Location Register (HLR) of the mobile cellular network is maintained when the cellular phone (2) , in idle mode, enters into the coverage area of the AP (1) , selects/re- selects its cell and camps under it. Similarly, the registration of the user on the VLR/HLR is maintained when the cellular phone (2) , in active mode, enters into the coverage area of the AP (1) and camps under it when the cellular phone

(2) changes to idle mode. In these two cases, the AP (1) is located on same the location area of the user, so that any paging signal from the server base station is detected by the CNA module (39) and relayed to the cellular phone (2) across the bridge (7) and the CPA module (38) . If the cellular phone (2) is turned on when it is in the coverage area of AP (1) and camps under it, the cellular phone (2) cannot be registered on the VLR/HLR with the same location area where the AP (1) is located. Therefore, in this case, it is necessary to update the location area of the cellular phone (2) . In order to update the location area of the cellular phone (2) camped under the AP (1) , the LAC that is sent on the control carrier of the AP (1) is changed. Then, the cellular phone (2) and all the others cellular phones that are camped under the AP (1), request for the location update by sending the location update request message. The location update request is accepted for all cellular phones, except for the cellular phone (2) that camped by last under the AP (1) . The location update request of the cellular phone (2) is rejected forcing it to re-select the cell of the server base station of the mobile cellular network, complete the authentication and registration on the mobile cellular network. After a defined period of time, the AP (1) backs its original LAC on the control carrier, so that the cellular phone (2) re-selects the AP (1) cell and maintaining its registration on the VLR/HLR of the mobile cellular network. Optionally, this procedure can be repeated regularly in order to update the registration of the all camped cellular phones on the VLR/HLR.

[105] e) Services Access Processes

Following are described some exemplary embodiment of the processes involved in the present invention to access the voice, SMS and data/multimedia services by the users with their cellular phone camped under the AP (1) . In the present invention, the access to these services can be achieved through the fixed network or mobile cellular network. Initially, the processes to access the services through the fixed network are described: [106] Access of the services through the fixed network (ADSL/cable modem infrastructure) :

[107] - Mobile originated VoIP call (MOVC) : the AP (1) performs, through the CPA module (38), the mobile originated call processes, as performed by the BSS or RAN of the mobile cellular network. First, the CPA module (38) exchanges the necessary signaling information (messages of the layer 3 of the protocol stack) with the cellular phone (2) that originated the call across the air interface (5) . When the call is established, it transmits/receives the voice media (voice signal encoded by voice coder at the cellular telephone) to/from the cellular phone (2) also across the air interface (5) . The CPA module (38) activates the VoIP client of the BBA module (40) , exchanges signaling information with the VoIP client as well as transmits/receives the GSM media to/from the VoIP client. The VoIP client of the BBA module (40) uses protocols, such as SIP and RTP/RTCP, to establish the connection with the VoIP server or PABX (21) and for the transmission/reception of the voice media, respectively. At the AP (1) side, the voice signal is encoded and decoded by the cellular phone (2) while, at the network side, the voice signal is encoded and decoded by the MGw (18) .

[108] - Mobile terminated VoIP call (MTVC) : the mobile terminated VoIP call through the fixed network occurs when the incoming call is destined to the fixed number or VoIP number of the subscriber. The VoIP client of the BBA module (40) exchanges signaling information, such as SIP and IAXP2, with the VoIP server or PABX (21) for the incoming call across the ADSL/cable modem infrastructure. Additionally, the BBA module (40) activates and exchanges the necessary signaling information with the CPA module (38) that performs the processes of mobile call termination as performed by BSS or RAN. The CPA module (38) exchanges the signaling information with the cellular phone (2) across the! air interface (5) . When the call is established, the CPA modu .e (2) transmits/receives the voice media to/from the cellular pjhone (2) also across the air interface (5) .

[109] - Message Origination: the CPA module (38) performs the necessary standard processes for mobile message origination as performed by the BSS or RAN. This way, the CPA module (38) exchanges the necessary signaling information with the cellular phone (2) that originated the message and receives it across the air interface (5) . The CPA module (38) relays the message to the SMS client. The SMS client transmits the message to the SMSC (22) by using a protocol such as ?MPP, across the BBI (40) and ADSL/Cable modem infrastructure.

[110] - Message Termination: the SMSC (22) sends the message received from the user's cellular network or fixed network to the SMS client of BBA module (40), through the Internet by using a protocol such as the SMPP. The SMS client relays the received message to the CPA module (38) that performs the processes for mobile message termination as are performed by the BSS/RAN. After the connection with the cellular phone (2) is established, the message is transmitted to cellular phone (2) across the air interface (5) .

[Ill] - Data/multimedia access: the CPA module (38) performs the necessary processes of the protocol layers of the BSS or RAN, SGSN (23) and GGSN (25) of the mobile cellular network, such as "GPRS attach" and connection configuration (activation "PDP (Packet Data Protocol) context") for data/multimedia access. Additionally, the CPA module (38) encapsulates the IP packets received friom the Internet into the GPRS packet, identifies the IP address of the cellular telephone camped on the AP (1) and transmits the GPRS packets to the identified IP address. Similarly, in the reverse direction, the GPRS packets received from the cellular phone are encapsulated into IP packet and transmitted via the fixed Internet .

[112] Access to the services of the mobile cellular network:

[113] The access to the services across the air interface with the server base station of the mobile cellular network uses the concept of a bridge (7) between the cellular phone camped under the AP (1) and the server base station.

[114] - Mobile Termination Call (MTC) : an exemplary embodiment of messages flow, between the cellular phone (2) camped under the AP (1) and the server base station (3) of the mobile cellular network, during call termination procedure to the MSISDN number, is shown in figure 10. F2 of the pair of frequencies (69) is the frequency selected for the control and traffic carrier of AP (1), and F2 ' of the same pair of frequencies is the frequency of the uplink carrier. Fl of the pair of frequencies (80) is frequency of the control carrier of the server base station, and Fl' of the same pair of frequencies is the frequency of the uplink carrier. The CNA module (39) relays, across the bridge (7), the control messages from the server base station (3) to the CPA module (38) that, in turn, relays the message to the cellular phone (2) camped under the AP (1) and vice-versa. This way, the paging request message (81) received by the CNA module (39) from the server base station (3) in the frequency Fl, is relayed to the cellular phone (2) by the CPA module (38) in the frequency F2. Similarly, the channel request message (82) received by the CPA module (38) from the cellular phone (2) in the frequency F2' , is relayed to the server base station by the CNA module (39) in the frequency Fl' . The immediate assignment message (83) received by the CNA module (39) from the server base station in the frequency Fl, is relayed to the cellular phone (2) by the CPA module (38) in frequency F2. The immediate assignment message (83) assigns a dedicated control channel, including the frequency of the carrier, to the cellular phone (2) . Therefore, after receiving the immediate assignment message, the cellular phone (2) starts to communicate directly with the server base station (3) across the air interface (8). Further messages are exchanged directly between the cellular phone (2) and the server base station (3) bypassing the AP (1) .

[115] - Message Termination: the cellular phone (2) camped under the AP (1) receives the message from the server base station (3) across the CNA module (39), bridge (7) and the CPA module (38) . As in case of the mobile terminated call processes, after receiving the immediate assignment message, when a dedicated control channel is assigned to the cellular phone (2), it starts to communicated directly with the server base station (3), across the air interface (8), so that further messages are exchanged directly between the cellular phone (2) and the server base station (3) bypassing the AP (1) .

[116] - Mobile Call Origination (MOC) : in the present invention, when the cellular phone is camped under the AP (1), the mobile call origination across the air interface of the server base station (3) via the CNA module (39), bridge (7) and the CPA module (38), is performed as follows: the user enters a specific code, for instance, "001+SEND", and after enters the "ISDN number +SEND" or "MSISDN number + SEND". When the code "001" is received, the CPA module (38) relays the channel request message with the originating speech call cause, received from the cellular phone (2), to the server base station across the bridge (7) and the CNA module (39) . This way, the call origination is performed as the cellular phone was camped under the server base station. Alternatively, the mobile originated call across the air interface of the server base station can be performed by the user entering a supplementary service (SS) code, for instance, "*01# + SEND". When the CPA module (38) receives the SS code, the LAC that is sent on the control carrier of the AP (1) is changed. Therefore, the cellular . phone (2) and all the others cellular phone that are camped under the AP (1) , request for the update location by sending the location update request message. The location update requests of all cellular phones are accepted, except of the cellular phone (2) that requested the SS, whose location update request is rejected. Since the cellular phone (2) had its location update request rejected, it re-selects the cell of the server base station (3) of the mobile cellular network, completes the authentication and registration on the mobile cellular network. After a defined period of time, the AP (1) backs to its original LAC on the control carrier, so that the cellular phone (2) re-selects the AP (1) cell. Before this period of time is expired, the user can originate calls across the air interface of the server mobile radio station.

[117] - Message origination and Internet access: in the present invention, when the cellular phone is camped under the AP (1), the message origination and Internet access across the air interface of the server base station, are performed when the user enters a specific code, for instance, "002+SEND", before starting the message origination or Internet access. When the code "002" is received, the CPA module (38) relays the next channel request message with the originating data call cause, received from the cellular phone (2), to the server base station across the bridge (7) and the CNA module (39) . Alternatively, the message origination and Internet access across the air interface of the server base station are performed by the user enetring a SS code, for instance, "*01# +SEND" . When the AP (1) receives the SS code, it starts the same alternative method for the mobile call origination across the air interface of the server base station, which enables the cellular phone to reselect the cell of the server base station. While the time period to re-select the AP (1) cell is not expired, the user can originate messages or access the Internet across the air interface of the server mobile radio station.

Claims

38 WHAT IS CLAIMED IS

1. A system characterized by enabling the users to access, bypassing the mobile cellular network, the services of public switching telephony network, IP telephony network and Internet, across the broadband ADSL/cable modem infrastructure, using their own cellular phone, of any model for a given technology, without any modification or installation of software application on the cellular phone, neither any configuration or installation of new components in the core of mobile cellular network, independently of mobile operator and keeping the facilities to access the mobile cellular network across the air interface of the base station, consisting at least of:

a) Access point;

b) Cellular phone;

C) VoIP Server;

D) MGw (Media Gateway) .

2. A system according to claim 1, characterized by enabling the users to use their own cellular phone as wireless extension of a PABX, consisting at least of:

a) Access point;

b) Cellular phone;

c) PABX;

d) MGw.

3. A system according to claim 1 or 2, characterized by enabling the cellular phones around the access point:

a) Automatic selection/reselection of the cell of the access point even when it is operating out of licensed frequency band of mobile operators.

b) Automatic camping under the access point even when it is operating out of licensed frequency band of mobile operators . c) Automatic authentication and registration of the cellular phones in the mobile cellular network when it camps on the access point.

4. A system according to claim 1 or 2, characterized by enabling the users to perform, using their own cellular phone camped under the AP:

a) Mobile originated VoIP call to fixed, cellular or IP telephone, through the Internet as VoIP session, across the broadband ADSL/cable modem infrastructure.

b) Mobile originated call, as an option feature for the user, across the air interface of the mobile cellular network. c) Mobile terminated VoIP call from fixed, cellular or IP telephone, to the user ISDN number or VoIP number through the Internet as VoIP session, via the ADSL/cable modem broadband infrastructure .

d) Mobile terminated call to the user MISDN number across the air interface of the mobile cellular network.

e) Mobile originated/Mobile terminated message through a short message service center via the ADSL/cable modem broadband infrastructure .

f) Mobile originated message across the air interface of the mobile cellular network.

g) Mobile terminated message to the user MISDN number across the air interface of the mobile cellular network.

h) Transmission and receiving of data/multimedia, bypassing the cellular network, via the ADSL/cable modem infrastructure .

i) Transmission and receiving of data/multimedia across the air interface of the mobile cellular network.

5. The access point of the claims 1 and 2, characterized by the fact of being embodied as a standalone device comprising: a) Standard air interface of the cellular base station side;

b) Standard air interface of the cellular phone side;

c) Broadband interface for ADSL/Cable modem;

d) Simcard interface, as optional;

e) Module comprising a standard radio frequency front end and physical layer of cellular phone side;

f) Module comprising a standard radio frequency front end, physical layer and protocol stack layers of mobile cellular network side;

g) Bridge between the modules of the cellular phone and mobile cellular network sides;

h) Broadband module comprising a VoIP and SMS clients and, optionally, IP router.

6. The access point of the claims 1 and 2, characterized by the fact of being embodied as an device connected to a PC, laptop or netbook, smartphone or tablet, through an interface such as universal serial bus (USB), comprising:

a) Standard air interface of the cellular base station side;

b) Standard air interface of the cellular phone side;

c) Interface to a PC, laptop or netbook, smartphone or tablet, such as USB;

d) Simcard interface, as optional;

e) Module of standard radio frequency front end and physical layer of cellular phone side;

f) Module of standard radio frequency front end and physical layer of mobile cellular network side;

h) Module of protocol stack layers of the mobile network side, VoIP and SMPP clients installed on the personal computer and running on its CPU.

7. A device according to claim 5 or 6, characterized by the fact that it can be integrated with the core of the fixed network or with the core of the mobile cellular network, independently, and be controlled by the network operator or by the user itself.

8. A device according to claims 5 or 6, characterized by the fact of weeping all the frequencies in the frequency band of the mobile operator to detect the carrier of the server base station around its location area, synchronization with the detected carrier of the server base station and selection of its control and traffic carrier, through a standard air interface of the cellular phone side embedded on it.

9. A device according to claim 5 or 6, characterized by the fact of automatically synchronizing with the server base station of mobile cellular network, acquiring the synchronization channel and reading the synchronism information through an embedded standard air interface of the cellular phone side.

10. A device according to claim 5 or 6, characterized by automatically: a) Selecting, through an embedded standard air interface of the cellular phone side, independently of the mobile operator, a frequency for its control and traffic carrier as the frequency with the lowest power of the cell neighbor list read from the control carrier of the server base station; b) Generating the control and traffic carrier in the selected frequency through an embedded standard air interface of mobile cellular network side, without causing interference to other systems; c) Enabling the selection/reselection of the cell of the device by the cellular phones around it.

11. A device according to claims 5 or 6, characterized by automatically: a) Selecting, in case of operation out of frequency band of mobile operator, through an embedded standard air interface of the cellular phone side, a frequency for an 42

auxiliary control carrier that broadcast a cell neighbor list out of frequency band of the mobile operator, as the frequency with the lowest power of the cell neighbor list read from the control carrier of the server base station; b) Generating the auxiliary control carrier in the selected frequency, through an embedded standard air interface of mobile cellular network side, without causing interference to other system; c) Allowing selection/reselection of the cell of the device when its control and traffic carrier is out of frequency band of mobile operators .

12. A device according to claims 5 and 6, characterized by allowing the creation of a list of authorized I SI, through an embedded simcard interface or remotely, so that the cellular phones that selected/reselected its control carrier, whose simcard has the IMSI registered in the list, can automatically camps under it or be rejected to the mobile cellular network, otherwise .

13. A device according to claim 5, comprising a VoIP and SMS clients, an IP router (optionally) and a broadband interface for ADSL/cable modem infrastructure that allows the user to perform with his cellular phone camped under it:

a) Mobile originated VoIP call to fixed, cellular or IP telephone, through the Internet as VoIP session, across the ADSL/cable modem broadband infrastructure.

b) Mobile terminated VoIP call from fixed, cellular or IP telephone, to the user ISDN number or VoIP number through the Internet as VoIP session, across the ADSL/cable modem broadband infrastructure .

c) . Mobile originated/Mobile terminated message through a short message service center via the ADSL/cable modem broadband infrastructure .

d) . Internet access across the ADSL/cable modem infrastructure . 43

14. A device according to claim 6, comprising a VoIP client, SMS client and an interface, such as USB, that allows the user to connect it to a PC, laptop or netbook, smartphone or tablet, and perform with his cellular phone camped under it:

a) Mobile originated VoIP call to fixed, cellular or IP telephone, through the Internet as VoIP session, across the personal computer connection with the Internet (ADSL/cable modem, WiFi or cellular modem) .

b) Mobile terminated VoIP call from fixed, cellular or IP telephone, to the user ISDN number or VoIP number through the Internet as VoIP session, across the personal computer connection with the Internet.

c) Mobile originated/Mobile terminated message through a short message service center across the personal computer connection with the Internet.

d) Internet access across the personal computer connection with the Internet.

15. A device according to claims 5 and 6, comprising standard air interfaces of cellular phone and base station of mobile cellular network, enabling the users to perform with their cellular phone camped under it:

a) Mobile originated call, as an option feature for the user, across the air interface of the mobile cellular network. b) Mobile terminated call across the air interface of the mobile cellular network.

c) Mobile originated/terminated message across the air interface of the mobile cellular network.

d) Internet access across the air interface of the mobile cellular network.

16. A device according to claims 5 and 6, characterized by the fact of registering the cellular phone in the VLR/HLR of the mobile cellular network when it camps under it. 44

17. A device according to claims 5 and 6, characterized by the fact of enabling the users, when their cellular phone is camped under the device, to reselect the cell of the base station of the mobile cellular network and camps under it manually, by entering a standard code for supplementary services .

18. A device according to claims 5 and 6, characterized by performing the automatic frequency correction of the local oscillator, based on the RF signal received from the server base station of mobile cellular network, as performed by the cellular phones.

19. A device according to claims 5 or 6 characterized by ciphering the voice signal and data by using a ciphering key, kc, in GSM system, from a set of kc and RAND pairs associated with a IMSI and created when the user inserts his simcard on the slot of the simcard interface or remotely by the network operator .

20. A device according to claims 5 or 6 characterized by authenticating the user by using a SRES (Signed RESponse) , in GSM system, from a set of SRES and RAND pairs associated with a IMSI and created when the user inserts his simcard on the slot of the simcard interface.

21. The method of detection of the control carrier of the server base station according to claim 8, characterized by sweeping all the carriers in the frequency band of the mobile operator, through a standard air interface of the cellular phone side, and selecting the carrier with the highest power as the control carrier of the server base station.

22. The method of synchronization with the server base station, according to claim 9, characterized by using a standard air interface of cellular phone side embedded on the access point to acquire the synchronization channel of the control carrier of the server base station and read the synchronism information.

23. The method of selection of the frequency of the control and traffic carrier of the access point, according to claim 10, characterized by reading, through a standard air interface of the cellular phone side embedded on it, the cell neighbor list from the control carrier of the server base station and selecting, among the frequencies of the list, the one with the lowest power as the frequency for the control and traffic carrier of the device.

24. The concept of the auxiliary control carrier according to claim 11, characterized by reusing the frequency of the carrier of a distant neighbor base station to broadcast a new cell neighbor list containing frequencies out of the frequency band of the mobile operator, enabling the cellular phones, around the access point, to camp under it, by reading the new neighbor list, even when operating out of the band of the mobile operator.

25. The method of selection of the auxiliary control carrier according the claim 11, characterized by reading, through a standard air interface of the cellular phone side embedded on it, the cell neighbor list from the control carrier of the server base station and selecting, among the frequencies of the list, the one with the lowest power as the frequency for the auxiliary control carrier of the access point.

26. The bridge concept between the cellular phone, camped under the access point, and the base station of the mobile cellular network, characterized by using two air interfaces interconnected each other inside the access point as through a bridge: a) An air interface with the cellular phone that follows the same standard of the air interface of the base station of the mobile cellular network and enables communication between the cellular phone and the device, b) An air interface with the base station that follows the same standard of the air interface of cellular phone and enables communication between the device and the base station of the mobile cellular network.

27. The bridge method characterized by enabling a transparent signaling information exchange between the cellular phone camped under the access point and the server base station of the mobile cellular network by using the bridge concept according to claim 26.

28. The methods of mobile originated/terminated call, mobile originated/terminated message and Internet access across the air interface of the mobile cellular network, when the cellular phone is camped under the access point, characterized by using the bridge method according to claims 26 and 27, to enable the signaling information exchange between the cellular phone camped under the access point and the server base station, up to a designation of a dedicated control channel when the cellular phone starts to communicate directly with the server base station through a new assigned carrier.

29. The method of frequency correction of local oscillator according to claim 18, characterized by the fact of being based on the RF signal received from the server base station of mobile cellular network, as performed by the cellular phones.

30. The method of authentication and registration of the cellular phone in the cellular network according the claim 16, characterized by: a) after the cellular phone camped under the device, forcing the cellular phone to reselect the cell of the server base station of the mobile cellular network by changing the location area code broadcasted on the control carrier and rejecting its location update request to the new location area; b) After the authentication and registration of the cellular phone in VLR/HLR of the cellular network, forcing the cellular phone reselect the cell of the device, by returning the original location code on the control carrier of the device and accepting the location area update request.

31. The method of manually reselect the cell of the base station according to claim 17, characterized by the fact of the device changing the location area code broadcasted on its control carrier when receive a supplementary service request from the cellular phone and, subsequently, rejecting the location updated request received from the cellular phone.

32. The ciphering method according to claim 19, characterized by creating a set of kc parameter and RAND pairs, in GSM system, associated with a IMSI on the access point.

33. The authentication method according to claim 20, characterized by creating a set of SRES parameter and RAND pairs, in GSM system, associated with the IMSI on the access point .