WO2009115560A1

WO2009115560A1 - Method and fixed-network adapter for connecting a mobile terminal to a fixed network

Info

Publication number: WO2009115560A1
Application number: PCT/EP2009/053217
Authority: WO
Inventors: Nicholas Keith Ord; Jörg WIENAND
Original assignee: Gigaset Communications Gmbh
Priority date: 2008-03-18
Filing date: 2009-03-18
Publication date: 2009-09-24
Also published as: DE102008014747A1

Abstract

A short-range radio interface (BT) of the mobile terminal (ME) can be used to connect the latter to a fixed-network adapter (BT2IP) having a short-range radio interface (BT), and the fixed-network adapter (BT2IP) is used to convert the short-range radio protocol into a Voice-over-IP protocol for a Voice-over-IP interface (VOIP), wherein the fixed-network adapter (BT2IP) acts in the sense of a Voice-over-IP server. The Voice-over-IP interface (VOIP) is used to signal sessions with voice transmission (voi) between the fixed network (PSTNJN) and the fixed-network adapter (BT2IP) and to transport the voice information (voi). As a result, mobile terminals such as GSM, UMTS, DECT or CDMA terminals can determine whether incoming or outgoing calls with voice transmission are intended to be switched via a VOIP network or a POTS network, thus achieving a maximum degree of flexibility.

Description

Method and landline adapter for connecting a mobile terminal to a

landline

description

Method and landline adapter for connecting a mobile terminal to a landline

In the home area of fixed networks and in business networks or corporate networks, the increasingly fixed mobile convergence, i. demanded access from Mobilfuπkendgeräten to a fixed network. Fixed networks are currently the telephone network or the Internet or networks with Internet protocol, in particular voice connections are to be controlled between the Mobilfuπkendgeräten and the terminals of the fixed networks. As a preferred protocol for the control or signaling of voice connections on the Internet or in networks with Internet Protocol, the standardized SIP protocol (Session Initial Protocol) is currently provided, the voice information according to the standardized RTP protocol (Real Time Protocol) - RFC standard 1889 and since 2003 in the RFC standard 3550 - is transported.

For the Fixed Mobile Convergence functions such as location of the connection initialization and to which of the terminal devices in the home or business or business area, a signaled connection to be mediated. For this, the caller of an incoming connection must be identified, whereby very different identifications are used in the respective networks. It should also be possible for a user of one of the terminals to select a network among the possible networks or a route in order, for example, to establish a cost-effective connection.

For Fixed Mobile Convergence, UMA (Unlicensed Mobile Access) and IMS (IP Multimedia Subsystem) protocols have been used, which are proprietary protocols different competitors that prevent cooperation between terminals of different competitors. For the realization of the Fixed Mobile Convergece, so-called Femto CeIIs - small cellular base stations - are planned, but the solutions are not focused on the business areas of the fixed network operators but on those of the mobile network operators. Furthermore, the realization of Femo CeIIs requires a high economic outlay.

The object underlying the invention is to provide an economical implementation for the communication of mobile terminals to and from fixed networks or a fixed mobile convergence, which can be used by different operators of fixed networks or mobile networks. The object is solved by the features of claims 1 and 10.

The essential aspect of the method according to the invention is to be seen in that a terminal of the mobile network is connectable via its short-range radio interface with a landline adapter having a short-range radio interface and using the landline adapter, the short-range radio protocol in a voice-over-IP protocol for a voice-over-IP interface is implemented, the fixed network adapter acts in the sense of a Voice-over-IP server. With the help of the Voice-over-IP interface, connections between the fixed network and the landline adapter are signaled.

A significant advantage of the invention is to be seen in the fact that the stand-alone landline adapter the complete adaptation of the short-range interface - advantageously a Bluetooth interface - to a voice-over-IP interface - advantageous with the standardized Session Initial Protocol and the RTP protocol - Accepts and thus following the Session Initial Protocol configured facilities such as gateways or servers can be used without modification, the gateways or servers need to have no knowledge of the mobile terminal ME. As a result, the economic outlay, in particular with regard to adaptations in the mobile terminal and in the gateway for the connection of mobile terminals - for example according to GSM, UMTS or DECT or CDMA terminals to fixed networks such as telephone network PSTN or the Internet is considerably reduced. Another advantage is that mobile terminals such as GSM, UMTS, DECT or CDMA terminals can determine whether incoming or outgoing calls are switched over a VOIP network or a POTS network, whereby maximum flexibility is achieved ,

Further advantageous developments of the method according to the invention and an embodiment of a fixed network adapter according to the invention can be found in further claims. In the following the invention and its developments are explained in more detail with reference to three drawings. Show

FIG. 1 shows a block diagram of a communication arrangement for carrying out the method according to the invention,

Figure 2 based on a layer model provided for in the fixed network adapter functions, and

FIG. 3 shows the structure of a communication session using a flow chart

Voice transmission via the fixed network adapter FA according to the invention.

FIG. 1 shows, in a block diagram, by way of example a communication arrangement in which the method or arrangement according to the invention is implemented, wherein only those components are shown which are necessary for explaining the method according to the invention.

A mobile terminal (ME) of a radio communication network - not shown has in addition to the radio interface of the communication network on a short-range radio interface, which is implemented in the embodiment by a Bluetooth interface BT. The mobile radio network represents, for example, a GSM (Global System for Mobile Communications) network or a UMTS (Universal Mobile Telecommunications System) network.

The Bluetooth interface BT of the mobile terminal (ME) can communicate wirelessly with a Bluetooth interface BT of a landline adapter BT2IP, provided that the mobile terminal ME enters the radio range of the Bluetooth interface BT of the fixed-network adapter BT2IP. Advantageously, information is transmitted via the Bluetooth interface BT, in particular voice information voi in the PCM format, i. logarithmically quantized in 8-bit samples. The signaling information si for a connection initialization is transmitted in accordance with the signaling protocol provided in the mobile radio network - for example according to the GSM protocol or the UMTS protocol.

In the fixed network adapter BT2IP, the signaling information si for a signaling protocol for voice transmission on the Internet - in the art known as Voice over IP (voip) - processed. For the exemplary embodiment, the standardized SIP protocol (Session Initial Protocol) is provided, whereby the standardized H.323 protocol is alternatively possible. The voice information voi is transmitted according to the RTP protocol (Real Time Protocol), wherein the RTP protocol acts as a transport protocol for the SIP protocol. The landline adapter BT2IP additionally has a voice-over-IP interface VOIP, which is connected to a gateway GW. In the fixed network adapter BT2IP interworking between the signaling protocol according to the mobile network GSM and Voice-ovβr-IP protocol is realized, the fixed network adapter BT2IP A acts in terms of a voice-over-IP server - indicated in Figure 1 by the name GSM and SIP , With the help of the Voice-over-IP interface VOIP connections or communication sessions between the fixed network and the fixed network adapter BT2IP signals and possibly carried out an adaptation of the language information voi to be transmitted in particular with regard to coding or compression.

The voice information voi transmitted in the Bluetooth protocol in PCM coding can, if necessary, be effectively adapted to the SIP SIP protocol by using a translation table. In this example, it is stated that the present in a compressed PCM coding voice information voi is encoded using a coder in a broadband voice information - for example, according to the standard G.722 for transmission over the local area network LAN. Usually, however, a recoding in a voice transmission is not required if the voice information voi in a suitable for transmission over the voice-over-IP interface VOIP, compressed form exists.

In the gateway GW, a voice-over-IP interface VOIP is likewise provided for communication with the landline adapter BT2IP, wherein the transmission network between the fixed network adapter BT2IP and the gateway GW is designed, for example, as a local area network LAN, for example an Ethernet. The signaling of a communication session, in particular with voice transmission, takes place in the local network LAN in accordance with the SIP protocol SIP, the SIP protocol SIP being based on the Internet protocol INP.

In the gateway GW a connection to a telephone network PSTN is realized according to the embodiment in addition to a connection to the Internet IN. In this case, known gateways GW can be used, in which a signaling according to the SIP protocol for the transmission of voice information voi over the Internet IN in accordance with the RTP protocol RTP is implemented and adaptation functions with respect to signaling and voice information transmission for connections in a telephone network PSTN are integrated. The connection to the Internet IN takes place from the home area advantageously via DSL connections - indicated by the designation DSL in FIG. 1 - and from business areas via broadband connections, e.g. VDSL.

FIG. 2 shows the layer structure used in the fixed network adapter BT2IP as a link between a mobile terminal ME and the voice-over-IP interface VOIP to the Internet IN or a local area network Network LAN is provided for signaling and voice information transmission and is implemented predominantly programmtechπisch.

The Bluetooth wireless interface BT is designed in accordance with the IEEE standard 801.15.1 and the physical layer forms a Bluetooth radio layer. The Bluetooth radio layer realizes the short-range radio interface and can be configured for different ranges and bandwidths. For the connection of a mobile terminal ME, an average bandwidth with two transmission channels is advantageous. The frequency range of the Bluetooth interface BT is 2.402 to 2.480 GHz.

In Bluetooth baseband - indicated in Figure 2 with the name Bluetooth Base - the information of the Bluetooth radio layer can be inserted into different physical data channels or transmitted from these to the Bluetooth radio layer, wherein a data channel for the synchronous data transmission, in particular for the transmission of voice information voi, and the other data channel for the asynchronous data transmission, in particular for the transmission of signaling information si is provided. For the protocol-compliant handling of the voice information voi in synchronous connections or communication sessions (SCO - Synchronous Connection Oriented) an SCO protocol layer SCO is provided. In this case, the voice information vio is transmitted synchronously in real time in fixed time slots to 8 bits. Analogously, an ACL layer is inserted for the transmission of the signaling information si for asynchronous connections (ACL - Asynchronous Connection Less).

Downstream of the ACL layer ACL is a link manager layer Unk, in which a connection is made between Bluetooth devices. With its help, the size of the data packets is negotiated, with which the signaling information si is transmitted.

The signaling information si is transmitted from the link manager layer Unk to a hands-free profile layer HFP. The hands-free profile specifies how to control calls from a mobile device ME to a hands-free device and vice versa, where hands-free devices typically represent hands-free devices in an automobile or headsets.

The voice-over-IP interface VOIP is physically implemented by an Ethernet ethernet layer, with which the fixed-network adapter FA is connected to the local network LAN formed by an Ethernet. With Ethernet, the data is transmitted via a transmission medium in the baseband. With regard to the physical properties and the collision method, the Ethernet or Ethernet layer is designed, for example, according to the IEEE standard 802.3. ■ Access to the Ethernet layer is controlled in an Ethermet MAC layer. In this data link layer, in particular the MAC addresses (Medium Access Control) are formed and managed, which are used for unambiguous identification of the devices connected to the local network LAN or the fixed network adapter BT2IP. The MAC addresses are assigned by a central unit of the local network - not shown.

The next layer represents the Internet Protocol layer IPS. In this, the well-known Internet Protocol IP is realized programmatically. According to the protocol stack illustrated in FIG. 2, a user datagram protocol layer UDP follows, which represents the transport protocol for the internet protocol IP. The User Datagram Protocol layer UDP controls the information transmitted via the Internet IN to the affected applications. According to the invention, the signaling and voice information si.voi is controlled to the uppermost layer, the application layer APPL.

The signaling information si of the Internet Protocol layer IPS is controlled to a SIP layer SIPS and the voice information voi to an RTP layer RTPS. The SIP layer SIPS is realized programmatically and realizes the SIP protocol SIP (Session Initial Protocol). The SIP SIP protocol controls the establishment of a communication session between two terminals and is specified in the RFC standards RFC 3261 and 2543. The SIP protocol SIP is mostly used in Internet telephony, i. Voice information transmission is applied via the Internet <N. The RTP protocol RTP is arranged in the user layer, with the aid of which the voice information is transmitted via the Internet to IN or IP-based networks. The transmission of the voice information voi takes place in special RTP data packets, which are currently specified in the RFC standard 3550. With the help of this protocol, multimedia information can also be transmitted via the Internet IN.

According to the invention, the user layer of the SIP protocol SIP and the hands-free protocol layer HFP of the Bluetooth interface BT connect the application layer APPL.

In this application layer APPL, the following essential functions are implemented for the fixed network adapter BT2IP:

SIP registration server - known in the art as a SIP registrar - for the gateway GW,

SIP user agent for the initiation of a communication session for a voice transmission,

- Conversion of SIP signaling requirements into commands of the hands-free-profile layer

HFP

- Conversion of status indicators of the hands-free profiles layer HFP into SIP commands or

Reply, controls the voice connections of the hands-free profile layer of the Bluetooth interface BT and

controls the voice information of the voice during a communication session with voice transmission

RTP protocol RTP into the SCO layer SCO of the Bluetooth protocol and vice versa.

The structure of a communication session with voice information voi via the fixed network adapter BT2IP according to the invention is explained on the basis of a flowchart shown in FIG.

As already explained, the landline adapter BT2IP acts as a SIP registrar. As a result, the gateway GW turns to the landline adapter BT2IP to obtain a unique SIP address. To do this, the gateway sends a REGISTER message to the landline adapter BT2IP or the SIP registrar. In the response message OK200, the gateway GW is informed of a unique SIP address, represented by a unique Internet address.

As soon as the mobile terminal ME enters the radio range of the Bluetooth interface BT of the fixed network adapter BT2IP, a message RING can be transmitted to the fixed network adapter BT2IP, initialized by the mobile terminal ME, whereby a connection establishment or a communication session is initiated. In response to this message RING using the protocol layers HFP, LINK and ACL a connection between the fixed network adapter BT2IP and the mobile terminal ME for the transmission of Signalisierυngsinformation si is established. Subsequently, a connection for the transmission of the voice information voi can be set up with the aid of the protocol layer SCO, wherein this structure is only performed if a connection or session is to be set up in the context of a call.

After receiving the SIP message RING in the fixed network adapter BT2IP a SIP message INVITE is formed in this and transmitted to the gateway GW. In a SIP message INVITE formed in accordance with RFC standard 3261, essentially information about message type, destination address (URI), SIP version, address, port number and the transport protocol for the IP response of the message is specified. The gateway responds with a message 100 TRYING. This status message signals to the fixed network adapter BT2IP that the structure of the session has been initiated. Gateway GW sends another SIP message 180 RINGING, which indicates that the terminal could be detected in the fixed network PSTN ₁ IN.

If the called terminal in the fixed network PSTN, IN calls from the mobile terminal ME or the handset is lifted - indicated in Figure 3 by the name OFF HOOK, the gateway GW a SIP message 200 OK formed and transmitted to the landline adapter BT2IN , The call acceptance by the called party is communicated to the mobile terminal ME by transmitting a message ATA, whereupon the latter sends back a message OK. This will be the Fixed network adapter BT2IP the receipt of the message ATA confirmed and established the connection through the SCO layer SCO, if this has not already been done - the setup is indicated in Figure 3 by the label ESTABLISH SCO. The SIP message 200 OK is confirmed by the fixed network adapter BT2IP with a SIP message ACK, with the help of the specified IP addresses now the session via the RTP layer RTPS is set up and then the two-sided transmission of voice information voi can begin - Figure 3 indicated by the designations ESTABLISH RTP and CONVERSATION.

After termination of the session or connection, for example, initialized by pressing the connection end button to mobile terminal ME - indicated in Figure 3 by the name ON HOOK - in the fixed network adapter BT2IP the connection to the SCO layer degraded - in Figure 3 by the name TERMINATE SCO indicated - and transmitted a SIP message BYE to the gateway GW, with which the session or connection with Sprachübertraguπg is triggered or reduced - indicated in the figure 3 by the term TERMINATE RTP. Dismantling is confirmed by the gateway GW by the SIP message 200 OK.

With the aid of the inventive method or fixed network adapter BT2IP, existing VOIP and POTS gateways connections to VOIP or ISDN networks or services arranged by mobile terminals ME via the home area can be set up. For this purpose, mobile terminals such as DECT or CDMA θ terminal can determine whether incoming or outgoing calls are placed on a VOIP network or a POTS network, whereby maximum flexibility is achieved.

Claims

claims

1. A method for connecting a mobile terminal (ME) to a landline network (PSTN, IN) which can be signaled via a short-distance radio interface (BT) of the terminal (ME) for this information transmission in accordance with a short-distance radio protocol,

- In which the terminal (ME) via its short-range radio interface (BT) with a one

Short-range radio interface (BT) having fixed network adapter (BT2IP) is connectable,

- using the landline adapter (BT2IP) to convert the short-range radio protocol into a voice over

IP protocol for a voice-over-IP interface (VOIP) is implemented and vice versa,

- in which with the help of the Voice-over-IP interface (VOIP) a sessions between the landline

(PSTN ₁ IN) and the landline adapter (BT2IP) signals and information is transported.

2. The method according to claim 1, characterized in that the mobile terminal (ME) with a mobile network (GSM, UMTS) is connectable according to a mobile radio protocol.

3. The method according to claim 1 or 2, characterized in that as a short-range interface (BT) realized Bluetooth interface (BT) in the fixed network adapter (BT2IP)

- a physical Bluetooth radio layer (Bluetooth radio), followed by

- A protocol-specific Bluetooth base layer (Bluetooth Baseband), each followed by

- An Asynchronous Connection Less layer transmitting the signalization information (si)

(ACL) and

- A Synchoronous Connection Oriented layer transporting the payload (voi)

(SCO), following this

- a session controlling link layer (link) and

- includes a handsfree profile layer (HFO) controlling Bluetooth devices.

4. The method according to any one of claims 1 to 3, characterized in that according to the Session Initial Protocol (SIP) configured Voice-over-IP interface (VOIP) in the fixed network adapter (BT2IP),

a physical layer (Ethernet) for a local area network (LAN),

a medium access layer (MAC) controlling access to the physical layer following

an Internet Protocol layer (IPS) implementing the Internet Protocol following

a Universal Data Protocol layer (UDPS) transporting the information, in each case following

a SIP layer implementing the Session Initial Protocol SIPS and a real time protocol layer (RTPS) transporting the payload (voi)

5 The method according to any one of claims 1 to 4, characterized gekennuzeichnet that the Bluetooth interface (BT) and the Voce-over-IP interface (VOIP) via an application layer (APPL) are adapted in terms of their protocols and transport functions

6 Method according to claim 5, characterized in that the application has the following functions for the adaptation

- Session Initial Protocol - registrar server for subsequent SIP devices,

- Session Initial Protocol - User Agent for the initiation of a communication session for

voice transmission,

- Conversion of SIP signing requests into commands of the Hands-Free-Profile layer

HFP

- Conversion of Status Indicators of the Hands-Free Profiles Layer HFP into Session Initial Protocol -

Commands or answers,

- Control the voice connections of the hands-free profile layer of the Bluetooth interface BT and

Control of the voice information voi of the RTP protocol RTP in the SCO layer SCO of

Bluetooth protocol during a voice transmission communication session and vice versa

7 Method according to one of the preceding claims, characterized in that via the Bluetooth interface (BT) the information representing a voice information (voi) is time-slotted and pulse-code modulated

8. Method according to one of the preceding claims, characterized in that by means of a gateway unit connected via a local area network (LAN)

- The Session Initial Protocol (SΙP) is implemented in a signaling protocol for a telephone network (PSTN) and vice versa, and / or

- The Session Initial Protocol (SIP) is adapted to the IP protocol (IP) for the Internet (IN) and vice versa

9. Method according to one of the preceding claims, characterized in that the coded voice information (voi) transmitted via the short-distance radio interface (BT) is transcoded into a voice information (voi) suitable for transmission via the Voice-over-IP interface (VOIP) and vice versa.

10. Fixed network adapter designed to carry out at least one of the preceding claims 1 to 8.