CA2052858A1 - Digital telecommunications system - Google Patents
Digital telecommunications systemInfo
- Publication number
- CA2052858A1 CA2052858A1 CA 2052858 CA2052858A CA2052858A1 CA 2052858 A1 CA2052858 A1 CA 2052858A1 CA 2052858 CA2052858 CA 2052858 CA 2052858 A CA2052858 A CA 2052858A CA 2052858 A1 CA2052858 A1 CA 2052858A1
- Authority
- CA
- Canada
- Prior art keywords
- subscriber station
- code
- calling
- subscriber
- telecommunications system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/42—Systems providing special services or facilities to subscribers
- H04M3/424—Arrangements for automatic redialling
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/42—Systems providing special services or facilities to subscribers
- H04M3/48—Arrangements for recalling a calling subscriber when the wanted subscriber ceases to be busy
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M2201/00—Electronic components, circuits, software, systems or apparatus used in telephone systems
- H04M2201/36—Memories
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M2242/00—Special services or facilities
- H04M2242/22—Automatic class or number identification arrangements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/42—Systems providing special services or facilities to subscribers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/42—Systems providing special services or facilities to subscribers
- H04M3/42025—Calling or Called party identification service
- H04M3/42034—Calling party identification service
- H04M3/42059—Making use of the calling party identifier
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q3/00—Selecting arrangements
- H04Q3/72—Finding out and indicating number of calling subscriber
Abstract
Abstract A digital telecommunications system with a central ex-change (10) and a plurality of subscriber stations (20a-20d) is disclosed in which the calling subscriber station (20a) sends to the exchange (10) a calling signal con-taining the code of the called subscriber station (20b), and in which the exchange (10) records the code of the calling first subscriber station (20a). According to the invention, the exchange (10) includes a callback memory having a plurality of locations (11a-11d) each associated with one of the subscriber stations (20a-20d) and capable of storing the code of this subscriber station, and the called, second subscriber station (20b) has a callback function button (21) whose operation after release of the connection between the first (20a) and the second subscriber station (20b) generates a callback signal which causes the code of the calling first subscriber station (20a) to be read from the call-back-memory location (11b) associated with the second subscriber station (20b). This code is used as a desti-nation code for calling back the first subscriber station (20a).
Figure 1
Figure 1
Description
2~28~
Digital Telecommunications _ystem The present inven.tion relates to a di.gi.tal telecommuni-cations system compris;ng a central exchange and a plural;ty of subscr;ber stat;ons wherein a call-ing first subscriber station sends to the exchange a cal:lingsignal containing the code of the called se-cond subscr;ber station, and where;n the central ex-change records the code of the call;ng f;.rst subscriber station.
Such a d;gital telecommun;cations system is known. A
serious drawback of such dig;tal telecommunications systems~
which adversely affects user convenience, ;s apparent from the follow;ng descr;pt;on of an everyday s;tua-t;on: A f;rst subscr;ber at a first subscriber sta-. tion A is calling a second subsGriber at a second subscriber -station B. It is normally easily possible for the se-~:~ cond subscriber to establ;sh the ;dentity of the call-ing first subscr;ber from the contents of the conver~at;on~
However, the second subscr;ber is unable to determ;ne wh;ch f;rst subscr;ber station A the call;ng first subscriber is : actually using, i.eA, whether ~he f;rst subscriber is calling from h;s own subscriber station or fro~ another subscriber's station. This is part;cularly di.sadvanta-geous if, after termination of the conversation, the first subscriber wants to call back the second subscriber . in order to discuss a problem that has arisen afterwards, ~i or to communicate to the f;rst subscriber an unexpected :
..
~: .
20528~8 ;dea. If the subscriber station A, from wh;ch the first subscriber called, is not the first subscriber s own station, but some other subscriber station of the disital telecommunications system, it will be nearly impossible for the second subscriber - or possible only with much effort - to reach the first subscriber again.
To avoid th;s disadvantage, the invention has for its object to improve a d;g;tal telecommunications system of the above kind in such a way that the calling sub-scriber can be called back in a particularly simple manner~
The invention is characterized in that the central ex-change includes a callback memory having a plurality of memory locations each associated with one of the subscriber stations oF the digital telecommunications system and capable of storing the code number of one of said subscriber stations, that after establish-ment of a connection between the first subscriber station and the second subscriber station, the code of the calling first subscriber station ;s stored in that memory lo-cation of the callback memory which is associated with the second subscriber station, that the second sub-scriber station has a callback function button whose ope-ration after release of the connection between the first and the second subscriber station ge~erates a callback signal which causes the code of the calling first sub-scriber station to be read from the memory location of the callback memory, and that the code of the f;rst sub-scriber station read from the callback memory is used - :
205~8~8 as a destination code for calling back the first suh-scriber station.
By the measures accord;ng to the invent;on, a dlg;tal telecommunications system is provided which ;s charac-terized by its particular suitability for everyday use.
The callback memory in the central exchange allows the called subscriber to reach the calling subscriber by the depression of a button even if the latter subscriber con-ducted the conversation just term;nated not from h;s own station~ but from another subscriber's station. Such a service feature prov;des ;ncreased user conven;ence and extends the range of appl;cations of the digital tele-communications system considerably.
Further advantageous features of the invention are de-fined in the subclaims.
. , .
Further details of the invention will become apparent from the following description of an embodiment of the ;nvention taken ;n conjunction with the accompanying drawing, whose single figure is a schematic represen-tation of a dig;tal telecommunications system in accordance w;th the invention.
The digitial telecommunications system sho~n in the figure has a central exchange 10 to wh;ch several subscriber stations 20a, 20b, 20c, and 20d are connect-ed. The central exchange 10 has a convent;onal control unit 12 which controls all processes required in the central exchange 10 for establishing a connection be~
tween two subscriber stations. Each subscriber station 20a-20d, after being activated by suitable measures, ... . . ~ , ~ . .... - ,- . , .
,; , .
: . . . :
:-: . .. . - .
:,.", : . : ' -, . :
20528~
e.g., by lifting the handset and dialling the code of the desired subscriber station, sends a calling signal contain;ng the code of the called subscriber station to the central exchange 10. The control unit 12 of the central exchange analyzes the calling signal and then establishes a line connection between the calling sub-scriber station and the called subscriber station in the conventional manner.
The construction and operation of such a d;gital tele-communications system are familiar to those skilled in r the art and hence need not be described here in detail.
What is important is that the central exchange 10 in-cludes a callback memory 11 which communicates with the control unit 12 of the central exchange 10. The callback memory 11 has a number of locations 11a-11d equal to the number of subscriber stations 20a-20d for which the callback feature is to be provided. The in-dividual locations 11a-11d of the callback memory 11 are designed to be capable of storing the complete code of at least one subscriber station. Writing and reading of the code of a subscriber stat;on 20a-20d of the di-gitial telecommun;cations system are controlled by the control un;t 12.
The operat;on of the digital telecommunications system is as follows. In the follow;ng description, it will be assumed by way of example that a connection is to be established between the calling, first subscriber station 20a and the called, second subscriber station 20b.
.
. .
- : :
' ~ , . .
%~28~8 After the handset is l;fted and the desired call number - the code of the second subscriber station 20b - is dialled, the first subscriber station 20a sends the calling signal to the central exchange 10, as described above. The first subscriber station 20a is either a subscriber station of a closed digital telecommunications system - e.g., a telephone set of an in-house telephone system - or a direct-access subscriber station connected to a pubLic ISDN (Integrated Services Digital Network) exchange. These two cases differ only in that the code of the calling first subscriber station 20a is determined differently: In the first case, the codes of the sub-scriber stations 20a-20d are stored at the central ex-change 10. Identification - and, thus, storage of the code number - of the calling first subscriber station ., 20a is effected in the manner known per se, namely v;a a com-bination of this code number and the line connection over which the calling signal is transmitted from the calling first subscriber station 20a to the central exchange 10, said combination being stored in the control unit 12. If the calling first subscriber station 20a is a subscriber station connected to an ISDN exchange, its code is~contained in the calling signal, so that this subscriber station is identifiable by a suitable analysis of the calling signal in the control unit 12.
What is important is that the calling subscriber station generates and transmits to the central exchange 10 a calling signal which permits the central exchange 10 to identify the calling, first subscriber station 20a and, thus, to record the code of this station.
The central exchange 10 establishes a connection with the . , ~ . .. .. - .
2~528~8 second subscriber station 20b in a manner known per se.
After the second subscriber has answered the call from the second subscriber stat;on 20b, the latter generates an acknowledge signal and transm;ts ;t to the central exchange 10~ The acknowledge signal, which is fed to the control unit 12 of the central exchange 10, causes the code of the f;rst subscr;ber station 20a to be stored in that location of the callback memory 11 which is associated w;th the second subscriber station 20b, i.e., in location 11b.
After termination of the conversation between the first and the second subscriber, the code of the first subscriber station 20a remains stored in the callback memory 11 of the exchange 10.
If the second subscriber wants to call back the first subscriber, this can be done in a straightforward manner: Calling back the person Last called by the second subscriber - ;.e~, the first subscriber - requires only the depression of a special function button 21 of a pushbutton assembly 22 of the second subscriber station 20b. It is also possible to initiate the callback by pushing a particular combination of buttons of the push-button assembly 22 or - if the subscriber station 20a-20d is a dial telephone set - by a particular sequence of operat;ons of a rotary dial. The second subscriber sta-tion 20b then ~ransmits a callback signal to the exchange 10 which causes the code of the first subscriber station 20b to be read from location 11b of the callback memory 11 and used as a call destination code. The central exchange 10 then establishes the connection with the first subscriber station 20a using the code stored in the callback memory 11.
, : . :
,. . .
20~2~8 To sum up it can be said that the callback faci.li.ty in the digita( telecommun;cat;ons system represents an extremely efficient ser~ice feature ~hich greatly improves user con~enience and extends the ran.ge of applications of such a telecommunications system.
Digital Telecommunications _ystem The present inven.tion relates to a di.gi.tal telecommuni-cations system compris;ng a central exchange and a plural;ty of subscr;ber stat;ons wherein a call-ing first subscriber station sends to the exchange a cal:lingsignal containing the code of the called se-cond subscr;ber station, and where;n the central ex-change records the code of the call;ng f;.rst subscriber station.
Such a d;gital telecommun;cations system is known. A
serious drawback of such dig;tal telecommunications systems~
which adversely affects user convenience, ;s apparent from the follow;ng descr;pt;on of an everyday s;tua-t;on: A f;rst subscr;ber at a first subscriber sta-. tion A is calling a second subsGriber at a second subscriber -station B. It is normally easily possible for the se-~:~ cond subscriber to establ;sh the ;dentity of the call-ing first subscr;ber from the contents of the conver~at;on~
However, the second subscr;ber is unable to determ;ne wh;ch f;rst subscr;ber station A the call;ng first subscriber is : actually using, i.eA, whether ~he f;rst subscriber is calling from h;s own subscriber station or fro~ another subscriber's station. This is part;cularly di.sadvanta-geous if, after termination of the conversation, the first subscriber wants to call back the second subscriber . in order to discuss a problem that has arisen afterwards, ~i or to communicate to the f;rst subscriber an unexpected :
..
~: .
20528~8 ;dea. If the subscriber station A, from wh;ch the first subscriber called, is not the first subscriber s own station, but some other subscriber station of the disital telecommunications system, it will be nearly impossible for the second subscriber - or possible only with much effort - to reach the first subscriber again.
To avoid th;s disadvantage, the invention has for its object to improve a d;g;tal telecommunications system of the above kind in such a way that the calling sub-scriber can be called back in a particularly simple manner~
The invention is characterized in that the central ex-change includes a callback memory having a plurality of memory locations each associated with one of the subscriber stations oF the digital telecommunications system and capable of storing the code number of one of said subscriber stations, that after establish-ment of a connection between the first subscriber station and the second subscriber station, the code of the calling first subscriber station ;s stored in that memory lo-cation of the callback memory which is associated with the second subscriber station, that the second sub-scriber station has a callback function button whose ope-ration after release of the connection between the first and the second subscriber station ge~erates a callback signal which causes the code of the calling first sub-scriber station to be read from the memory location of the callback memory, and that the code of the f;rst sub-scriber station read from the callback memory is used - :
205~8~8 as a destination code for calling back the first suh-scriber station.
By the measures accord;ng to the invent;on, a dlg;tal telecommunications system is provided which ;s charac-terized by its particular suitability for everyday use.
The callback memory in the central exchange allows the called subscriber to reach the calling subscriber by the depression of a button even if the latter subscriber con-ducted the conversation just term;nated not from h;s own station~ but from another subscriber's station. Such a service feature prov;des ;ncreased user conven;ence and extends the range of appl;cations of the digital tele-communications system considerably.
Further advantageous features of the invention are de-fined in the subclaims.
. , .
Further details of the invention will become apparent from the following description of an embodiment of the ;nvention taken ;n conjunction with the accompanying drawing, whose single figure is a schematic represen-tation of a dig;tal telecommunications system in accordance w;th the invention.
The digitial telecommunications system sho~n in the figure has a central exchange 10 to wh;ch several subscriber stations 20a, 20b, 20c, and 20d are connect-ed. The central exchange 10 has a convent;onal control unit 12 which controls all processes required in the central exchange 10 for establishing a connection be~
tween two subscriber stations. Each subscriber station 20a-20d, after being activated by suitable measures, ... . . ~ , ~ . .... - ,- . , .
,; , .
: . . . :
:-: . .. . - .
:,.", : . : ' -, . :
20528~
e.g., by lifting the handset and dialling the code of the desired subscriber station, sends a calling signal contain;ng the code of the called subscriber station to the central exchange 10. The control unit 12 of the central exchange analyzes the calling signal and then establishes a line connection between the calling sub-scriber station and the called subscriber station in the conventional manner.
The construction and operation of such a d;gital tele-communications system are familiar to those skilled in r the art and hence need not be described here in detail.
What is important is that the central exchange 10 in-cludes a callback memory 11 which communicates with the control unit 12 of the central exchange 10. The callback memory 11 has a number of locations 11a-11d equal to the number of subscriber stations 20a-20d for which the callback feature is to be provided. The in-dividual locations 11a-11d of the callback memory 11 are designed to be capable of storing the complete code of at least one subscriber station. Writing and reading of the code of a subscriber stat;on 20a-20d of the di-gitial telecommun;cations system are controlled by the control un;t 12.
The operat;on of the digital telecommunications system is as follows. In the follow;ng description, it will be assumed by way of example that a connection is to be established between the calling, first subscriber station 20a and the called, second subscriber station 20b.
.
. .
- : :
' ~ , . .
%~28~8 After the handset is l;fted and the desired call number - the code of the second subscriber station 20b - is dialled, the first subscriber station 20a sends the calling signal to the central exchange 10, as described above. The first subscriber station 20a is either a subscriber station of a closed digital telecommunications system - e.g., a telephone set of an in-house telephone system - or a direct-access subscriber station connected to a pubLic ISDN (Integrated Services Digital Network) exchange. These two cases differ only in that the code of the calling first subscriber station 20a is determined differently: In the first case, the codes of the sub-scriber stations 20a-20d are stored at the central ex-change 10. Identification - and, thus, storage of the code number - of the calling first subscriber station ., 20a is effected in the manner known per se, namely v;a a com-bination of this code number and the line connection over which the calling signal is transmitted from the calling first subscriber station 20a to the central exchange 10, said combination being stored in the control unit 12. If the calling first subscriber station 20a is a subscriber station connected to an ISDN exchange, its code is~contained in the calling signal, so that this subscriber station is identifiable by a suitable analysis of the calling signal in the control unit 12.
What is important is that the calling subscriber station generates and transmits to the central exchange 10 a calling signal which permits the central exchange 10 to identify the calling, first subscriber station 20a and, thus, to record the code of this station.
The central exchange 10 establishes a connection with the . , ~ . .. .. - .
2~528~8 second subscriber station 20b in a manner known per se.
After the second subscriber has answered the call from the second subscriber stat;on 20b, the latter generates an acknowledge signal and transm;ts ;t to the central exchange 10~ The acknowledge signal, which is fed to the control unit 12 of the central exchange 10, causes the code of the f;rst subscr;ber station 20a to be stored in that location of the callback memory 11 which is associated w;th the second subscriber station 20b, i.e., in location 11b.
After termination of the conversation between the first and the second subscriber, the code of the first subscriber station 20a remains stored in the callback memory 11 of the exchange 10.
If the second subscriber wants to call back the first subscriber, this can be done in a straightforward manner: Calling back the person Last called by the second subscriber - ;.e~, the first subscriber - requires only the depression of a special function button 21 of a pushbutton assembly 22 of the second subscriber station 20b. It is also possible to initiate the callback by pushing a particular combination of buttons of the push-button assembly 22 or - if the subscriber station 20a-20d is a dial telephone set - by a particular sequence of operat;ons of a rotary dial. The second subscriber sta-tion 20b then ~ransmits a callback signal to the exchange 10 which causes the code of the first subscriber station 20b to be read from location 11b of the callback memory 11 and used as a call destination code. The central exchange 10 then establishes the connection with the first subscriber station 20a using the code stored in the callback memory 11.
, : . :
,. . .
20~2~8 To sum up it can be said that the callback faci.li.ty in the digita( telecommun;cat;ons system represents an extremely efficient ser~ice feature ~hich greatly improves user con~enience and extends the ran.ge of applications of such a telecommunications system.
Claims (6)
1. Digital telecommunications system comprising a central exchange (10) and a plurality of subscriber stations (20a-20d) wherein a calling first subscriber station (20a) sends to the exchange (10) a calling sig-nal containing the code of the called second subscriber station (20b), and wherein the central exchange (10) records the code of the calling first subscriber station (20a), c h a r a c t e r i z e d i n that the cen-tral exchange (10) includes a callback memory (11) hav-ing a plurality of memory locations (11a-11d) each associated with one of the subscriber stations (20a-20d) of the digital telecommunications system and capable of storing the code number of one of said subscriber stations (20a-20d), that after establishment of a connection between the first subscriber station (20a) and the second subscriber station (20b), the code of the calling first subscriber station (20a) is stored in that memory location (11b) of the callback memory (11) which is associated with the second subscriber station (20b), that the second subscriber station (20b) has a callback function button (21) whose operation after release of the connection between the first (20a) and the second subscriber station (20b) generates a call-back signal which causes the code of the calling first subscriber station (20a) to be read from the memory location (11b) of the callback memory (11), and that the code of the first subscriber station (20a) read from the callback memory (11) is used as a destination code for calling back the first subscriber station (20a).
2. A digital telecommunications system as claimed in claim 1, characterized in that the first subscriber station (20a) is part of a closed telecommunications system wherein the code of the first subscriber station (20a) is stored at the central exchange (10).
3. A digital telecommunications system as claimed in claim 1, characterized in that the first subscriber station (20a) is a subscriber station connected to a public ISDN exchange, and that the calling signal sent out by the calling first subscriber station (20a) contains the code of the calling first subscriber sta-tion (20a).
4. A digital telecommunications system as claimed in claim 1, characterized in that the callback function button (21) of the second subscriber station (20b) is a special function button of a pushbutton assembly (22).
5. A digital telecommunications system as claimed in claim 1, characterized in that the function of the callback function button (21) of the second subscriber station (20b) is implemented by pushing buttons of the pushbutton assembly (22) in a particular sequence.
6. A digital telecommunications system as claimed in claim 1, characterized in that the function of the callback function button (21) of the second subscriber station (20b) is implemented by a par-ticular sequence of operations of a rotary dial.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19904031857 DE4031857A1 (en) | 1990-10-08 | 1990-10-08 | DIGITAL TELECOMMUNICATION SYSTEM |
| DEP4031857.5 | 1990-10-08 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2052858A1 true CA2052858A1 (en) | 1992-04-09 |
Family
ID=6415841
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2052858 Abandoned CA2052858A1 (en) | 1990-10-08 | 1991-10-07 | Digital telecommunications system |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0480233A2 (en) |
| JP (1) | JPH04264867A (en) |
| CA (1) | CA2052858A1 (en) |
| DE (1) | DE4031857A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2126897C (en) * | 1993-09-01 | 1998-09-22 | Anthony R. Dipierro, Jr. | Telephone call notification feature |
| US5533100A (en) * | 1994-07-29 | 1996-07-02 | At&T Corp. | Communications system call complete arrangement |
| US6782268B1 (en) * | 1998-06-23 | 2004-08-24 | Lucent Technologies Inc. | Method and apparatus for tracking call history for mobile and wireline users accessing the network on different ports for subsequent calls |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5829259A (en) * | 1981-08-17 | 1983-02-21 | Hitachi Ltd | Calling subscriber calling system |
| JPS60144063A (en) * | 1984-01-06 | 1985-07-30 | Nec Corp | Recalling system |
| JPS62171363A (en) * | 1986-01-24 | 1987-07-28 | Nec Corp | Call-back connection system |
| DE3910485B4 (en) * | 1989-03-31 | 2007-12-20 | Siemens Ag | Method for automatically switching through a connection between two terminals of a telephone system |
-
1990
- 1990-10-08 DE DE19904031857 patent/DE4031857A1/en not_active Withdrawn
-
1991
- 1991-09-24 EP EP19910116204 patent/EP0480233A2/en not_active Withdrawn
- 1991-09-30 JP JP27867291A patent/JPH04264867A/en active Pending
- 1991-10-07 CA CA 2052858 patent/CA2052858A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| DE4031857A1 (en) | 1992-04-09 |
| EP0480233A3 (en) | 1994-01-12 |
| JPH04264867A (en) | 1992-09-21 |
| EP0480233A2 (en) | 1992-04-15 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |