AUTOMATIC EXCHANGE SYSTEM FOR MARITIME RADIO TELEPHONE

Abstract: Automatic exchange system for maritime telephone allowing the onboard user to dial directly the needed telephone number without having to go through a coast radio station operator. At the end of the dialling, the onboard set sends, towards the land station, its identification code in addition to the telephone number required. Coast radio station computer scans its user's file and, if the received identification code is acknowledged, it provides to call automatically the dialled telephone number connecting the land subscriber with the onboard user, recording traffic data for billing and statistics.

Description: Automatic exchange system for maritime radio telephone. 5. Even though the introduction into the Italian radio-shore- stations of the CM8300 systems is a progress for the modernization of the maritime radio telephone service, the CI AT thought it right to research for an even more advanced technical-operating solution consisting in the 10. gradual introduction of automatic exchange telephony systems which could allow to the board user both the direct dialling of the wanted telephone number and access to the hand-operator position. This new system enables the automatic calls accounting, a more elastic management of the available paths and to carry out rapid statistical controls in order to 15. get a better use of the available resources. This system, managed by a computer, can be at every moment rapidly reorganized according to the traffic, requirements. Both the hand operating system C 8300 and the automatic implement system CM8600 were emologated by the Italian 20. "Istituto Superiore delle Poste e Telegrafi" with the certificates n. IST/5.3/2/2/22 and n. 5/3/2/3/27 of the 08.11.86 dated Oct. 3, 1985 and Nov. 8, 1986 respectively. Project principles. 25. The automatic exchange telephony system (called CIMAT-CM8600 by the building firm) is made-up with a highly specialized software and uses refined data-transmission techniques in order to assure, with high probabilities of success, the conversation between the shore-station and 5. the interested boardset. Moreover, the employed coding systems assure the certainty of the information addressed, an essential requisite of an accounted telephone system. For a higher guarantee, the board user can ensure himself the control of his own use and consequently the exclusiveness of this 10. utilization, employing, for the activation of the set, a secret code (pass-word), which can be input through the keyboard and identified by the earth-set. Furthermore it is foreseen that the user can .be informed, through a special display, of the link development and if required he can receive 15. from earth, at the end of the conversation, the pulses amount. The complete modularity of the system allows to add or take off each time single radio-paths dedicated to the automatic exchange telephony. 20. This allows, at every moment, to dimension and give the service a new structure according to the traffic demand, the available lines and the operating requirements of the stations. A central processing unit provides for the maintenance, the management of the ships-and subscribers files and for the recording of the data 25. concerning the accounting to the users of the carried out conversations. A software is also provided, which enables the planning of the links to use, the check of the occurred and occurring traffic and the operating 5. link for the data transfer from and to a hierarchically superior data processing centre. Structure and characteristics of the CM8600 system. - System composition. - Earth-sets. 10. The units which are to be linked to the central unit of the manual system CM8300 in order to enable the automatic exchange telephony service are as follows: - Management unit of the automatic exchange telephony GTP001 and its power-supply. 15. - Central Processing Unit with its peripheric units. Boards-sets. The terminal board-radio-unit (UTR001) can be linked to every duplex or se iduplex set through the low-frequency path which the handset is 20. normally linked to. As it is an intelligent terminal, the board-set can be made in different models among which the basic one can only monitor the available radio channel of the dialled telephone number, and is provided with the keyboard for the input of the password, the dialling of the telephone 25. number and the management of the ten memories. More developed models are also provided with serial outputs for the link with the set of the peripheric units and devices for selective calls. 5. Technical working characteristics. Automatic exchange telephony management unit (GTP001). This unit is set-up so that it can locate two channels for the management of the radio-paths and a fixed equipment which enables the operator of the radio-shore-statioπs to make the monitoring of the 10. link or hand-operate secting both the earth-side and the sea-side link. The there contained moduli of the radio-channel management have the function to talk, through duplex radio-channels, with the corresponding board-sets. Such moduli are essentially made up by an interface with the radio-set, by coding and decoding circuits for the exchange of 15. controls and con irmations between board and earth, by a logic unit for the management of the link with the board user and for the search and engament of the telephonic line more suitable for the communication addressing towards the earth user. The system can manage up to a maximum of 12 automatic incoming lines. 20. The coversation between the earth-and board-sets takes place through digital words containing the identification code of the board user. This gurantees to both correspondents the certainty of the informations addressing. For a better link guarantee, the transmission of this data take place 25. with a FSK modulation, and the digital word structure is such that a SUBSTITUTE SHEET longitudinal parity check gives the content certainty. At the reception decoding, confrontation and parity check are arranged. 5. All the transmitted tones are in the audio band-width and correspond to the standards of the matter. Each modulus is moreover provided with the signallings necessary to the visual monitoring of the operating state. The modularity and the complete operational indipendence of the single channels allow to expand, as much as one likes, the system channel by 10. channel. It belongs to this unit the monitoring complex provided with a loudspeaker and a handset in order to enable the operator to check the link in voice service of the two radio-paths switching the console operation from automatic to manual. An operational link with the central processing unit, where the ships 15. and users-file is located, enables to test the identification codes sent out by the board-sets. To the same processor are then sent, for the storing, all the data relative to the carried out links. Central processing unit. 20. It is a processor where the ships-file coupled with the passwords is located. The software of the machine allows to carry out the tests necessary to qualify the calling user to the use of the telephone service and to analyse the requested number. At the end of the processing of the data received from the board 25. terminal, by means of the automatic switchboard, it sends to the latter the informations necessary for the search of the hierarchically more suitable free line. It has also the function to save the data proving 5. the set up link for the relative charge and to print in real time the carried out radio-telephone communications. When required, the unit can be linked with processing units of a higher level, in order to bring up to date the resinding file and to send the previously memorized data for the charge and the traffic analysis. 10. The basic software chosen for the management of the implementative system is of a standard type and is provided with strictly tested components, of easy use for the management, maintenance and application development in a multifunctional system. Moreover, qualifing element of the system is the application component, 15. planned with a high flexibility and modularity in order to set up adjustments to specific requirements and more and more refined and complicated operating developments. The system structure is provided with a series of procedures and arrangements which permit: 20. - the carrying out of the automatic radio-telephone traffic with selective standards that aim at the best exploitation of the available resources and signallings which enable the user to follow step by step the link development; — the continuous visual display on a TV, monitor of the present traffic 25. situation and of the status of the links, with menus and suggestions which make easier the conversation between operator and machine; - the flexible and gradual activation of additional functions; 5. - the revision of the qualified watercrafts-file; - the management of the data necessary to the billing and their printing in real time; - the back up of the system and the save of the data; - the input and identification of the operator's code. 10. The processing speed and the capacity of the users-and traffic-input- file depend on the applied hardware and mainly on the volume of the employed mass-memories. The P.C. model with a 20 Mb hard disc can have a users-file of about 10,000 items and a storage capacity of the carried out traffic of about 15. 6,000 conversations and can serve at the same time up to 4 links at a time. The miniprocessor model with a 40 or 60 Mb hard disc can serve more peripherals at a time, make at the same time more diversified processes, have a users-file of many tens of thousand items (even 100,000) and 20. serve at the same time 10 or more links. Terminal board-radio unit (UTR001). This is an intelligent unit which talks with the terrestrial station in an interactive way according to a digital exchange protocol. 25. This unit is essentially provided with interface-circuits with the radio-set and coding and decoding devices of the codes which are very similar to the codes of the corresponding terrestrial set. 5. Both versions, with alphanumeric display or LED diods, allow the monitoring of the different development states of the link and the visual display of the dialled telephone number which can have a maximum of 16 digits. The telephone keyboard is normalized according to the international 10. standards. A special signalling shows the free channel and qualifies the set to carry out the link which can only start pressing the apropriate engagement button. The management logic of the board-terminal is specially so planned to 15. avoid operating faults from the user which can spoil the working. The analogic data transmission part is located on a FSK model which has become an industrial standard, compatible with the Bell 1103/113/108/202 and CCITT V.21/V.23 recommendations. The structure is completed by an EPROM which can maintain indefinitely, 20. without any power-source, the data relative to the 10 telephone numbers which can be programmed in the memory. In addition to this, the board terminal has been planned with a wide possibility of hardware and software expansion which allows a parallel/serial link with external input/output peripherals (printer, 25. video terminal, board selective calls signalling sets, decoding systems SUBSTITUTE SHEET etc . ) 5. Description of a procedural sequence. The description is related to procedure which has a successful completion. General. The terrestrial set signals the available duplex radio-channel sending 10. in the air a continuous tone. To signal steadily that the radio-channel is reserved to a special use, during the shgort intervals of the data exchange and in alternative to the central tone, a continuous busy tone is broadcast. 15. The board-set, before getting the free channel, has already memorized the password and the dialled telephone number. Consequently the moment when the engagement button is pressed till the setting up of the link with the terrestrial user, everything occurrs automatically. 20. Link procedure. To bring into action the board-set the password should be supplied. Then, after the dialling of the telephone number, a free radio-channel is searched and when the indication of free channel is given, the channel engagement button can be pressed which only in this case is 25. enabled to operate. __»s .a -^- S li ιl - i i k__ Oi --_-___ . As soon as the terrestrial station receives the engagement signal, the continuous free tone is cleared away so as no else board-set can be enabled to use the same radio-channel. A busy tone takes the place of the free tone. Automatically the board-set sends its identification code (with the password introduced by the user) and the dialled telephone number. 10. On earth the identification code is checked in the ships-and users-list contained in the memory of the central processing unit. The dialled telephone number is then processed. 15. Automatically the terrestrial set, on the ground of the dialled prefix, chooses the more suitable free telephone line. According to the hierarchic order of the used line (of the compartment, department, intercompatment etc.) it provides the adjustment of the prefix digits. 20. After the connection the board-set enables the handset. The conversation after a disengagement command is sent to board. This disengagement can be sent at any time also from board to earth. After the link, automatically, the terrestrial set gives again the 25. continuous tone of free channel. Description of the main used signallings. .The terrestrial sets transmit: 5. "Free channel" tone. It is a continuous tone which enables the board-set to start the call- sequence that is a message constituted by the matriculation number of the apparatus, the password, the telephone number and the parity checks. "Busy channel" tone. 10. It is a continuous tone transmitted during the data-escape intervals between board and earth. It is used to signal the engagement of the radio-channel. "Clearing" command.. It is a command which, in the inside of the earth-set, has RESET 15. functions. It is sent each time the earth-set thinks it right to end a link with not aknowledged commands or identification codes, or if the user is not qualified to the service use because of default or other reasons, or in case of unidentified or incorrect telephone number, if the telephone 20. line is not available or the earth user is busy (45sec.) or not present, and because of conversation end. At the receiving of this command the board-set is disabled and the sequence blocked. A special command coding produces in the set the signalling of the reason of the link end. 25. To start a new call sequence it is necessary to operate manually. SUBSTITUTE SHEE "Repetition" command. If the terrestrial station considers the received engagement message 5. inadequate, it requires its automatic repetition. "Received" command. It is sent out if the engagement command coming from board is identified. The board-sets transmit: 10. "Engagement" command. It is sent out followed by the identification code and by the pre — dialled telephone number. This command can start only if the board-set was enabled by the receiving of the FREE CHANNEL TONE sent by earth. The reception at earth 15. of this command causes the immediate stop of the sending of the FREE CHANNEL TONE, so that no watercraft can rise this channel any longer for the automatic exchange service, as long as the channel is busy. "Clearing" command. It is a command which can be sent out at every time by the board—set; at 20. receiving it the earth-set will send out the "FREE CHANNEL" tone. Identification code. Nominative code. It gives the name of the watercraft for the following research by the 25. processor in the ships—file and is hardware cabled in the board—set. Password code. It is a secret code assigned to the subscriber to warrant the certainty 5. of the charge to the user. This code can also be used to parcel the use of some telephone links (trunk, international and intercontinental links) to the user. Called telephone number.It follows the identification code.

Claims: CLAIMS. This system is different from any similar systems available on the 5. international market, known to us, essentially for the following characteristics: Earth-set. - electronic circuits for the link with public telephone network, the 10. dialling, the automatic engagement of the lines and the exchange of the central principles; - possibility of operating both on automatic sixwire lines and twowire lines; - principles of the setting—up of the earth—board—earth data exchange, 15. signallings sequence and composition of the digital words; - management logic of the central processor and of both the hardware and software interfaces towards the public telephone network and radio—sets. Board-sets. - electronic circuits and hardware and software management logic of the 20. information and codes; - principles of the setting up of the board-earth-board data exchange, sequence of the signallings and composition of the digital words; - capacity of parallel serial link with other peripheric units; - monitoring on alphanumeric (or LED diods) display of the development 25. states of the link and of the telephone number; - use of the secret code to enable the link.

Inventors: CARTIA LUIGI, CARTIA, LUIGI
Applicants: CARTIA LUIGI, CARTIA, LUIGI
Application year: 1987
Main classification: H04Q7
IPC codes: H04W84