Abstract:
The telephone system of the invention combines at least one telephone terminal ( 40  to  43 ) and one microcomputer ( 38  to  40 ) using a set of software modules, especially a module for functions normally carried out by top range telephone stations: free hand functions, recorder telephone answering sets, fax/modems, storage of numbers, automatic dialling, display on the screen of a microcomputer, and/or a module for services normally centralised for a large number of users, and/or a module concerning new functionalities: Internet/Intranet access, vocal recognition, automatic reading, small capacity unit automatic exchanges.

Description:
FIELD OF THE INVENTION 
   BACKGROUND OF THE INVENTION 
   The present invention concerns a telephone system combining at least one telephone terminal, a microcomputer and a set of software modules installed in the microcomputer. 
   Generally speaking, a system of this type has already been proposed introducing a top range telephone terminal equipped with microprocessors and having a large number of functionalities adapted to the telephone function, including the fax function and the transmission of data function (modem). This terminal is connected to an office microcomputer which for the most part only carries out the role of an input/output terminal and includes software and the fax/modem circuits normally linked to a modem box. Thus, the price of the telephone terminal is naturally relatively high. 
   There is also a telephone system constructed around an Ethernet network to which a specific server is connected, as well as possible platforms to the switched telephone network or long-distance IP networks (Internet, Intranet) and also telephone stations. These telephone stations are directly connected to the Ethernet cable. The unit then functions as a unit automatic exchange (PABX). 
   It has been proved that this concept eliminates from the market all those entities or persons having microcomputers not connected onto the local network which covers almost all individuals and extremely small concerns, that is most of potential buyers. 
   In addition, the Ethernet connection significantly increases the cost of the telephone station as long as a specific server is used for execution of the telephone programmes. 
   Thus, the aim of the invention is to eliminate these drawbacks. 
   It starts by sating that the arrival of the high-speed bus, for example the USB standard equipment bus, procures an economic means of communication whose performances are compatible with the calculation power of the processor. 
   Thus, it offers a telephonic system characterised in that it utilizes, on the one hand, an “USB” telephone terminal reduced to its minimal functions of telephone interfaces to emit and receive phone calls even in the event of interruptions of current, this telephone terminal being connected to a micro computer by the intermediary of a bus, for example of type USB and, in addition, a set of software modules installed in the microcomputer, comprising at least:
         a software module concerning of functions up to now specifically installed in top-of-the-range telephones, in particular a telephone function free hands using a microphone and loudspeakers connected to the microcomputer, an automatic message recorder function, a modem-fax function, a memory function of numbers and automatic dialling, a function of displaying on the screen of the microcomputer and/or a broad band telephony function for example 7 Khz if the totality of the communication is carried out by numerical way   and/or a software module concerning of the services usually centralised in expensive systems planned for a great number of users in particular written messaging function and/or vocal messaging function and/or fax function and/or taxation function,   and/or a software module concerning of the new functionalities or usually making the object of specific systems, in particular telephony on Internet/Intranet networks, the release of macro-instruction on the recognition of caller, the voice recognition, the automatic reading, the telephone data management (in particular directory) and/or the automatic switchboard of small capacity function (for example 2 lines, 6 stations) if several telephone terminals are connected on same USB bus.       

   Similarly, the link between the controller and the microcomputer could include at least three channels, namely one channel for transferring data between the microcomputer and a telephone terminal and at least two audio channels respectively allocated to the link between the microcomputer and a telephone line and to the link between the microcomputer and a telephone receiver. 
   SUMMARY OF THE INVENTION 
   According to the invention, one important advantage of the solution consists of the fact that the software modules could include a “unit automatic exchange” (PABX) function. This function is particularly advantageous for a network assembly of a plurality of microcomputers. 
   In fact, it makes it possible to avoid having two separate networks, namely one for the telephone (this network being controlled by a unit automatic exchange) and the other for the computer system (possibly including a server): only the computer network suffices. 
   This results in obtaining significant savings as regards the equipment and the laying of the network. 
   In addition, the system of the invention could use a router to provide telephone communications via the IP network (Internet or Intranet). 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     There follow description of several embodiments of the invention, given by way of non-restrictive examples, with reference to the accompanying drawings on which: 
       FIG. 1  is a skeleton diagram of a telephone terminal according to the invention and able to be connected to an analog line (full lines) or to a digital line (broken lines); 
       FIG. 2  is a skeleton diagram of a simplified terminal; 
       FIG. 3  is a synoptic diagram of the main software modules able to equip the microcomputer to which the terminals of the invention are connected; 
       FIG. 4  is a diagrammatic representation of a configuration introducing a microcomputer and several terminals according to the invention; 
       FIG. 5  is a diagrammatic representation of a configuration introducing several network-assembled microcomputers; 
       FIG. 6  is a diagram illustrating a physical configuration of a distributed unit automatic exchange able to be used in the network of  FIG. 5 ; 
       FIG. 7  is a diagrammatic representation illustrating the software segment of a microcomputer used for administrating a network; 
       FIG. 8  is a synoptic diagram of the software modules of microcomputers intended for users in the assembly of the network shown on  FIG. 5 . 
   

   DETAILED DESCRIPTION 
   In the example shown on  FIG. 1 , the terminal of the invention includes three sub-units, namely:
         a “USB bus controller” sub-unit associated with a microcontroller  1 ,   a “line” sub-unit including interface circuits  2 ,  3  with the analog telephone line LTA (impedance adapter and 2/4 wire converter) and a digital/analog converter  4 ,   a “station” sub-unit including the combined interface circuits (digital/analog converter  5  and adapter  6 ) and dialling keypad associated with a display unit  7 .       

   The “line” and “station” sub-units are connected to an addresses/data/audio bus of the USB bus controller  1  by means of their respective digital/analog converters  4 ,  5 . Nevertheless, they are functionally independent and could be separated physically. It is preferably solely for reasons of economy and convenience that they be installed in a given block. 
   In this example, the “line” sub-unit further includes an adapter So  9  providing a digital link between the bus  8  and a services integration digital telecommunications network (RNIS), for example, on the bus So (4 wires) of this network. Of course, this digital link (shown by the broken lines) can be provided as a complement to or replacement for the analog line  2 ,  3 ,  4 , LTA. 
   In the absence of any connection to a microcomputer, the telephone terminal ( 1  to  9 ) is fed by a telephone line LTA and is able to send and receive calls, like any conventional basic telephone station. 
   In this example, the link between the controller  1  and the microcomputer PC  10  includes four channels, namely: one channel A for the transfer of data between the microcomputer  10  and the telephone terminal  1  to  9 ; three audio channels B, C, D with B and C being allocated to the microcomputer/telephone link, and a channel D allocated to the receiver link/microcomputer/telephone receiver  6 ′. 
   The telephone terminal shown on  FIG. 2  is a simplified version of the terminal of  FIG. 1  in which the “line” sub-unit is not installed. This terminal is suitable in a case where it is connected to a bus or a network to which several terminals are connected, at least one of said terminals being of the type shown on  FIG. 1  and including a “line” sub-unit. In fact, in this case, it is not necessary to have the same number of lines as telephone stations. The link between the controller  1  and the microcomputer  10  no longer includes more than two channels, namely the channels A and C. 
   Of course, the microcomputer  10  ought to include functional programmes able to ensure the management of the telephone terminals, especially as regards the internal communications (between the terminals themselves via the microcomputer  10 ) and external communications (between the terminals  1  to  9  and the telephone line(s) LTA, So). Thus, these functional programmes could include the following modules shown diagrammatically on  FIG. 3 :
         USB exchange module  21  between the microcomputer  10  and the telephone terminal  1  to  9 ;   Audio receiving and transmission modules  18 ,  19  at 64 kb/s or at 128 kb/s;   Switching module  20  at 64 kb/s or 128 kb/s;   Interface module  17  with the microphone and loud-speakers of the microcomputer. This module includes sound compression and sampling programmes  22  with a 7 kHz band width able to be used for end-to-end digital communications;   Voice compression and decompression modules  23 ′,  29 ;   IP Encapsulation and de-encapsulation modules (Internet, Intranet)  27 ,  30 ;   IP switching module (Internet, Intranet)  28 ;   Data modulation and demodulation modules  25 ,  22 ;   Audio file management module  26 ;   Data file management module  23 ;   Module  24  for converting data files into fax format;   RHM man/machine relation and management modules for the various functions  12  to  16 ;   General manager programme  11 .       

   More specifically, on  FIG. 3  the block  11  represents the general manager programme to which the various modules can be connected, namely: a recorder/answerer management module  12 , a fax management module  13 , a module  14  for managing switchings for transmissions at 64 kb/s, a module  15  for managing communications for communications on IP networks (Intranet/Internet) and an RHM and management module  16  for the other functions. 
   In this example, the microphone/loud-speaker interface  17  is connected to transmission  18  and receiving  19  modules which control a 64 kb/s switching module  20 . 
   The audio receiving unit  19  receives information from the USB exchange module  21  which directly manages the exchanges with the USB bus of the microcomputer  10 . 
   The audio receiving unit  19  sends its information to a demodulation module  22  and to a compression module  23 ′. 
   The demodulation module  22  transmits the demodulated information to a file management module  23  and/or to a fax conversion module  24 , these two modules being connected to the audio transmission unit  18  by means of a modulation module  25 . 
   The compression module firstly transmits the compressed information to an audio file management module  26  and secondly to a unit successively including an IP encapsulation module  27  and an IP switching module  28  connected bidirectionally to the LAN local network. 
   The IP switching module  28  in addition transmits information to a decompression module  29  (which also receives information from the audio file module  26 ) via an IP de-encapsulation module  30 . 
   The audio transmission module  18  receives the decompressed information originating from the decompression module  29  as well as information originating from the modulation module  25 . 
   Of course, in the case of independent users, the installation could be limited to a single USB telephone terminal connected on a microcomputer, also able to be used for communications: data a fax, receiving and sending. The user could benefit as desired from all or part of the previously described functional modules. 
   In the case of extremely small concerns, the representative equipment could be constituted by a microcomputer  10 , mainly used by the secretary, with one or two digital or analog telephone lines (here LT 1 , LT 2 ) and several telephone terminals ( FIG. 4 ). 
   All the terminals TTUA, TTUB, TTUC, two of which only, TTUA, TTUB, are equipped with a telephone line (LT 1 , LT 2 ), are connected on the USB bus of the microcomputer  10 . 
   The microcomputer  10  then plays the role of a small-capacity unit automatic exchange, said capacity in this example being fixed at two lines and three terminals, two of the terminals TTUA and TTUB being equipped with a telephone line (LT 1 , LT 2 ). 
   The basic functioning of this small-capacity unit automatic exchange shall be explained hereafter:
         1) One of the terminals (for example the terminal TTUA) wishes to establish a sending communication. On dialling the external call prefix, it asks the microcomputer  10  for a line, said microcomputer answering negatively if the two lines LT 1 , LT 2  are occupied. If this is not the case, the microcomputer  10  establishes the audio connection between a free line and the corresponding terminal via its switching module. It then orders unhooking up of the selected line. The terminal TTUA can then dial.   2) An external call arrives picked up by one of the terminals, for example the terminal TTUA, is for another terminal, for example the terminal TTUB. Here, a case is considered in which the bell sets of the set of free terminals are activated upon detection of ringing on a line. The first terminal which unhooks takes the call. After being advised of the communication, the user of the terminal TTUA dials the number of the terminal TTUB. On unhooking of the latter and after hanging up of the terminal TTUA, the connection is established by the microcomputer  10 .   3) The TTUC terminal (with no line) wishes to establish an initial communication:   This case is similar to case n° 1.   4) The TTUC terminal wishes to establish a local communication with the TTUB terminal. The user of the TTUC terminal dials the number of the TTUB terminal. On unhooking of the latter, the connection is established by the microcomputer  10 .       

   With three terminals, the microcomputer is this able at the most to have to switch three telephone communications (two external communications and one local communication). 
   It is frequently the case that in small companies, a LAN local network connects the various microcomputers PC 1  to PC 3  of the concern and, in certain cases, a router RO offers specific access to the Internet ( FIG. 5 ). Each working station (microcomputers PC 1  to PC 3 ) can be equipped with one or several telephone terminals TTU 1  to TTU 3 , each possibly being provided with access to the switched telephone network RTC (analog or digital telephone lines LT 1 , LT 2 ). 
   The communications between different working stations is then effected through the LAN local network exactly as they were effected through the USB bus in the case of extremely small concerns. However, switching is carried out under the IP protocol (Internet/Intranet). 
   Large concerns often have several local networks, each being allocated to one service. Thus, each defined entity can be equipped in the same way as a small concern of the type previously mentioned, the telephone lines RTC being able to be connected to the equipment of stations of the unit automatic exchange of the concern. As most of the telephone communications are basically internal to the service, the USB terminals equipment is able to effect significant savings concerning the size of the switch of the concern. It is also possible to provide certain stations with a direct telephone line RTC, the unit automatic exchange then no longer being used for inter-service communications. 
   With the size of the concern, the possibilities of vocal messaging become important. In fact, this service is currently for the most part installed and a significant source of costs including the equipment of USB telephones allows savings to be made. 
   As previously mentioned, the invention permits the embodiment of a unit automatic exchange distributed over a microcomputer-based local network having USB telephone terminals, such as the one illustrated on  FIG. 6 . 
   In this example, this unit automatic exchange introduces eight USB telephone terminals  30  to  37 , only three of the latter having a telephone line  40  to  43 . 
   The PC type microcomputers  30  to  40  amount to three and are interconnected by an Ethernet link under TCP/IP  44 . Each microcomputer PC 1    30  to  40  has one USB port and an Ethernet card. Three RTC telephone lines  41 ,  42 ,  43  are respectively connected to the terminals  30 ,  31 ,  33 . Each USB telephone terminal  30  to  37  is connected to a microcomputer  38 ,  39 ,  40  by means of a USB link and possibly to an RTC telephone line. 
   The software of the system for evaluating the distributed unit automatic exchange is broken down into modules and sub-modules. In the example shown on  FIG. 8 , it is broken down into eleven modules: 
   1) “USB Exchanges” Module (ECU) 
   This module is used to identify and format the messages circulating on the USB bus. It analyses the header of each message so as to route the data. It also carries out a translation of the physical address of the USB telephone terminal into its logic address. It includes three sub-modules:
         the “station” sub-module which transmits and receives the information coming from the “station” sub-module of the “signalling” module,   the “line” sub-module which transmits and receives the information coming from the “line” sub-module of the “signalling” module,   the “audio” sub-module which manages the transmission and receiving of word samples between the USB telephone terminal and the PC.       

   2) “Signalling” Module (SIG) 
   This module manages the telephone signalling of the USB telephone terminal. It includes two sub-modules:
         the “station” sub-module which analyses and processes the events coming from the “station” sub-module of the “USB exchange” module so as to transmit them to the “call processing” module. The “call processing” module sends back to it the actions to be carried out according to the state of the communication,   the “line” sub-module which analyses and processes the events coming from the “line” sub-module of the “USB exchange” module so as to transmit them to the “call processing” module. The “call processing” module sends back to it the actions to be carried out according to the state of the line.       

   3) “Call Processing” Module (TAP) 
   This module is a coordinator module and its role is to manoeuvre the condition of the communications. It knows the state of the USB telephone terminals it manages. 
   This module communicates with the various “call processing” modules of the other PCs of the network so as to know the state of the various USB telephone terminals. Thus, it is able to select a free RTC line during an outgoing call. 
   It also informs the various “call processing” modules of the state of the USB telephone terminals it manages. 
   This “call processing” module interrogates the “routing” module so as to know the actions to be taken according to the event and the state of the communication. Thus, it generates a list of actions. 
   The “call processing” module sends alarm messages (coming from the “maintenance” and “audio” modules) to the “administrator” PC by means of the TCP/IP link. 
   4) “Routing” Module (ACH) 
   This module is a data module. It contains information on the telephone terminals of the system (for example the telephone terminal with call restriction or telephone terminal with call on unhooking). It also contains the actions to be taken according to the telephone terminal in question, events and the state of the line. It includes the dialling plan. 
   5) “Switching” Module (COM) 
   This module carries out and cuts the audio communications inside the PC microcomputer according to the directives of the call processing. 
   6) “Telephone Operational” Module (SOT) (Not Shown) 
   This module coordinates the telephone modules inside a given PC. It manages delay times and launches each software module with the required recurrence. 
   7) “Maintenance” Module (MNT) 
   This module regularly interrogates the various modules having physical interfaces. These interfaces carry out the controls asked for and sends a report. Should a problem occur, it sends an alarm message to the administration module. 
   8) “Audit” Module (AUD) 
   This module checks the coherence of the telephone data. Should a problem occur, it sends an alarm message to the administration module. 
   9) “Measuring” Module (MES) 
   This module files all the traffic data concerning the telephone terminals connected to the USB bus of the PC. When requested by the administration module, it processes this data. 
   10) “User Interface” Module (IUH) 
   This module makes it possible to roughly display the state of the communications. 
   11) “Administrator Interface” Module (IAD) 
   This module, solely present in the administration machine, is able to configure the distributed unit automatic exchange. 
   Each “user” PC of the network is equipped with all the modules, except for the “administrator interface” module. This module, which is shown on  FIG. 7 , is solely present on the “administrator” PC of the network as a complement to the other software modules of user PCs (PCU block) which communicates with one another via the USB bus and TCP/IP Internet/Intranet links. 
   The distributed unit automatic exchange is able to:
         Route an incoming call onto the first USB telephone terminal from a previously defined list of telephone terminals. This list contains all the telephone terminals of the network. If the first telephone terminal is occupied, the incoming call is then directed towards the second telephone terminal of the list, and so on until the last terminal of the list.   Pass a communication toward the outside world, a free RTC line then being selected,   Establish a local communication between two USB telephone terminals on the same USB bus or by the use of the Ethernet link under TCP/IP,   Carry out a transfer of a communication of a USB telephone terminal to another USB telephone terminal.       

   These various functionalities are processed by a software in the computer and can be made simultaneously and independently. 
   At the current moment, the flowrate of a USB bus reaches 12 Mo/s, which is for the most part greater than the maximum flowrate of a telephone conversation (at least 128 kbits/s). 
   In addition to useful information, the information on the USB bus contains:
         a synchronisation frame,   a message header,   an error control.       

   Voice compression inside the PC makes it possible to obtain a band width of at least 128 kbits/s.