CA2037557A1 - Method for in-house voice and data communication through the in-house power supply - Google Patents
Method for in-house voice and data communication through the in-house power supplyInfo
- Publication number
- CA2037557A1 CA2037557A1 CA002037557A CA2037557A CA2037557A1 CA 2037557 A1 CA2037557 A1 CA 2037557A1 CA 002037557 A CA002037557 A CA 002037557A CA 2037557 A CA2037557 A CA 2037557A CA 2037557 A1 CA2037557 A1 CA 2037557A1
- Authority
- CA
- Canada
- Prior art keywords
- telegram
- controller
- micro
- house
- frequency
- 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
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
- H04B3/542—Systems for transmission via power distribution lines the information being in digital form
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
- H04B3/544—Setting up communications; Call and signalling arrangements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/71—Substation extension arrangements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M9/00—Arrangements for interconnection not involving centralised switching
- H04M9/02—Arrangements for interconnection not involving centralised switching involving a common line for all parties
- H04M9/022—Multiplex systems
- H04M9/027—Frequency division multiplex systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B2203/00—Indexing scheme relating to line transmission systems
- H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
- H04B2203/5429—Applications for powerline communications
- H04B2203/5437—Wired telephone
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B2203/00—Indexing scheme relating to line transmission systems
- H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
- H04B2203/5462—Systems for power line communications
- H04B2203/5466—Systems for power line communications using three phases conductors
Abstract
ABSTRACT OF THE DISCLOSURE
A method for in-house voice and data communication through the in-house power supply is described. Two transmission channels having different frequencies are used, and voice transmission is performed by means of frequency modulation of the carrier frequency. The method according to the invention employs two channels for voice and data transmission. Voice transmission is also performed, by means of frequency modulation. For data transmission, in particular for transmission of the dial information, a pulse modulation procedure is applied. The calling party transmits digital telegrams containing the necessary information such as the kind of action, source address and destination address. The called party responds by an acknowledgement telegram. Therefore, a hand-shake procedure is employed. The telegrams are generated in a simple way by switching the carrier frequency on and off.
The in-house power supply network represents a bus with two channels, the assignment of which is performed following a predetermined scheme during access to the network. By this method, a simple structure of a direct connection between two users is possible, and an in-house communication network can be built up in a simple way. A central exchange is not required. Connection of the in-house communication network to the external public telephone network is possible.
A method for in-house voice and data communication through the in-house power supply is described. Two transmission channels having different frequencies are used, and voice transmission is performed by means of frequency modulation of the carrier frequency. The method according to the invention employs two channels for voice and data transmission. Voice transmission is also performed, by means of frequency modulation. For data transmission, in particular for transmission of the dial information, a pulse modulation procedure is applied. The calling party transmits digital telegrams containing the necessary information such as the kind of action, source address and destination address. The called party responds by an acknowledgement telegram. Therefore, a hand-shake procedure is employed. The telegrams are generated in a simple way by switching the carrier frequency on and off.
The in-house power supply network represents a bus with two channels, the assignment of which is performed following a predetermined scheme during access to the network. By this method, a simple structure of a direct connection between two users is possible, and an in-house communication network can be built up in a simple way. A central exchange is not required. Connection of the in-house communication network to the external public telephone network is possible.
Description
2 ~ 3 ~ ~ . 7 METHOD FOR IN-HOUSE vOIcE_AND DATA l2l____ICATION THROUGH
THE IN-HOUSE POWER SUPPLY
~ he invention relates to a method and to a device for in-house voice and data communication, i. e.
transmission of voice and data signals, between communication terminals, in particular telephone-like devices, using at least two transmission channels, the in-house power supply lines being used as carrier for the transmission of information. Such communication systems with signalling of dialling forming in connection with a known private telephone system a small extension system ; without dedicated lines are known in the art from DE 37 07 310 C2 and DE 37 07 308 C2.
The communication systems described in the prior art referenced above comprise one central adapter unit and one or more exterior adapter units coupled to power supply lines. The central adapter unit also provides for ;~20 communication between the external public telephone network and the in-house communication network through a postal ~;~line transmission unit. To one exterior adapter unit is connected a respective normal extension phone set. In the exterior adapter unit, a hook switch splits the connection ~;~25 line in one carrier-frequency transmitting and receiving channel each having an adequate arrangement in the central adapter unit. Transmission of voice is effected by frequency modulation of the carrier frequency of the respective transmitting channel. Signalling of dialling is ef~ected over pilot-tone transmitters and receivers by means of selector relays, such that the establishment of a connection of one extension terminal with another one will take place over the central adapter unit.
A principle object of the invention is to provide a method allowing transmission of voice and data on the in-. .
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2~3~ .i 7 house power supply lines with small expenditure, and to allow a direct connection of a user with another one of a possibly large number of users on the in~house network, `~ without a central exchange or a bus master being required.
~- 5 The method of the invention is characterised as a method for in-house voice and data communication through the in-house power supply, using at least two transmission channels, voice communication being effected by means of frequency modulation, wherein data communication between the communication terminals, in particular the information for the structure of the connections, is performed in digital form by means of pulse modulation, and data communication between the communication terminals through ; 15 the in-house power supply operating as a bus consisting of two channels is effected by a handshake procedure.
one transmission channel is assigned to the calling party, and a second transmission channel is ; 20 assigned to the called party. The transmission channels have respective frequencies of 109 kilohertz and 131 kilohertz, with a maximum frequency variation of ~F = 3.5 ~ kilohertz, and are assigned to the called user and the ~~ calling user respectively.
~ 25 :.., According to one aspect of the invention, digital ~ telegrams are generated by switching the carrier frequency -`, !, on and off, and the set of a telegram consists of four blocks with block lengths L1, L2, ~ and L4, such that in the first block a "start of telegram" identification is transmitted, and the three remaining blocks, the sequence of which is arbitrary but predetermined, contain the ~i information "type of telegram", "source of telegram" and 1 "destination of telegram", and, if necessary, a header ~ 35 block of length Lo is transmitted prior to the telegram. -20~ 4j 'i The cora of the invention consists in a method for in-house voice and data communication between communication terminals, in particular telephone-like devices, using the in-house power supply. communication is effected between terminals through at least two transmission channels and no ;~ central exchange, e.g. in the form of a central adapter installation is required. When limited to two transmission channels, the in-house power supply is adapted as a bus with two carrier-frequency channels. The method according to the invention provides that exchange of data is achieved in digital form by pulse modulation of the carrier, and - that transmission of voice is effected by frequency modulation. The digital data exchange, in particular for dial set-up of a connection, is performed by means of data telegrams. When dialling, a hand-shake method is applied, ^~ i.e. upon receiving a "call telegram" of a call the called device will respond by an "acknowledgement telegram". For carrying-out the method, a transmitting and a receiving channel are assigned to the calling and the called parties ~ 20 respectively following a predetermined scheme. This scheme `~I of assignment may consist, e.g. in that the calling party , has always the channel having higher frequency as ; transmitting channel, and the channel having lower ` frequency as receiving channel.
The telegrams have a definite structure. Thus, e.g., a telegram comprises four blocks of block lengths L~, and L4 bits. The block lengths may be different or identical. The block transmitted first always contains a start of telegram identification, e.g. for a block length ~; 30 4 bits, the code 1010. Ths three remaining blocks contain information on the type of telegram, the source address and 'l~ the destination address of the telegram~ The type of telegram determines the type of action to be taken. Under 1~ certain circumstances, it is necessary to transmit, prior j 35 to transmitting the telegram, a leader block of defined ~ length, in order to activate other, inoperative, users.
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The method according to the invention is, thereforei, particularly advantageous in that data transmission in the form of telegrams with acknowledgement allows for a simple structure of the ~ommunication link between two users without central exchange. In inoperative condition, the users are on the power supply which serves as a data bus, and can accept either one, or both, talker as well as listener functions. The calling user accepts automatically the role of the bus master when initiating a call. Thus a central exchange or control station, i.e. a dedicated bus master is not required. The method allows for a great flexibility with regard of possible future applications by defining further activities in the in~ormation block type of telegram.
; The device of the invention is characterised as a i ~evice for in~house voice and data communication between communication terminals through the in-house power supply, ~ voice communication being effected by means of frequency r", 20 modulation of the carrier frequency of the transmitting channel, said device comprising a mains coupler with power supply unit; a transmitting channel; a receiving channel;
and a micro-controller with a network controller performing control of the device and establishment of a communication 25 connection with other communication terminals by exchange of digital telegrams with acknowledgement operation and transmitting the telegrams by means of pulse modulation.
' 1 .
~`~ The device according to the invention, in the 30 following called a network telephone, contains a network coupler with integrated power supply unit, a receiver circuit, a transmitter circuit, a micro-controller and a ~; periphera} unit. It is particularly advantageous that each network telephone is provided with its own "intelligence", 35 because of the micro-controller. This micro-controller performs control of the complete network telephone, in ~4 ~ .
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- 2~373~j~
particular the micro-controller controls communication with other communication devices, which may be, in particular, other network telephones. By transmitting digital telegrams comprising the information l~start o~ telegram identification", "type of telegram", "destination of telegram" and "source of telegram", a simple and direct structure of the connections is possible. There will also not be reguired a central exchange, as the called device knows, through the information "destination of telegram", - 10 that it is addressed, and through the information "type of telegram" the order to be performed. Through the information "source of telegram", it is possible to perform , an acknowledgement of the call.
;~ Another advantageous embodiment of the invention can be seen under the term "collision csnsiderations~. As long as the network is not occupied, all users have equal access to the network. If the network is occupied, and a device tries to establish a second connection, it will obtain the information "busy". Collisions can only then occur when two devices try to establish a connection with ~;`j a period of time of approximately 20 ms. In this case, there are two possibilities:
a) The called party cannot respond because of a mutilated telegram. Both callers obtain a "busy" signal.
25b) The called party recognizes the incoming telegram from the first caller and can transmit now an answering telegram. If he has recognized correctly the call address, a communication is established, and the second caller obtains a "busy" signal.
30~
If the called party has not recognized correctly the call address, case a) will apply. Collisions on the in-house network can, thus, be resolved safely.
35~ Another advantage of the invention is that the device offers great flexibility~with regard to possible . ~
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future applications by defining, e.g. further activities in the information block "type of telegram", or by extension of the telegrams by additional information blocks.
- The calling device occupies a transmitting channel and a receiving channel following an arbitrary, but predetermined scheme, which can be adapted such that the calling user occupies always the channel of higher ~10 frequency as transmitting channel, and the channel of lower :frequency ac receiving channel. This means that the called user automatically uses the lower frequency as a transmitting channel, and the higher frequency as a receiving channel. In an inoperative condition, all devices are listening, according to this scheme, on the higher frequency as receiving channel. The receiving and the transmitting channels of each device are, therefore, convertible with regard to frequency. The configuration scheme, once set-up together with the ~elegram system, 20 allows establishment of communication directly from one -device to another, without a central exchange with a pilot-r~tone dialling system being necessary.
In a simple way, an internal house communication system i8 achieved by using at least two devices according to the invention.
In the following, a preferred embodiment of the invention is described in more detail with reference to the appended drawings, wherein:
Figure 1 is a schematic block diagram of the network telephone of the invention;
Figure 2 is a schematic diagram of an in-house ~extension system on the in-house power supply; and : ~
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Figure 3 is a schematic diagram of a network interface for connection of the in-house telephone system to the external telephone system. -~
.
Referring now to Figure 1, there is shown ~ block ; diagram of a network telephone being intended for in-house use through the in-house power supply. The network telephone comprises five functional groups: a mains coupler ~- 1, a receiving section 2, a transmitting section 3, a micro-controller 4, and a peripheral unit 5. The mains coupler 1 is separated from the remaining components accommodated in a hand set, and is connected to the hand set over a four-wire cable. The mains coupler 1 contains a power transformer 10 with a rectifier. Mains voltage is ,~ 15 transformed down to 15 volts ~low voltage), and is then transformed into a pulsating d.c. voltage. The latter is then reduced in the hand set to the required operational d.c. voltages of 12 volts and 5 volts, and is stabilized.
The pulsating d.c. voltage is supplied to the micro-; 20 controller 4 over the input 45, as it contains the information on the zero passage of the mains voltage. This zero passage information is used for synchronization purposes of the telegram transmission and reception. The mains coupler 1 can be connected by a protective plug to mains 13.
The receiving section 2 of the network telephone consists of a chain of three band filters 20, 22 and 24, to each of which are added amplifiers 21, 23 and 25, ~t;~ ~ respectively. ~he filtered and amplified f.m. signal is ~ed to a demodulator 26. From there, the voice signal transformed back to band base position passes to an ~fo : amplifier 27 and is supplied to a receiver cup 28. The demodulator 26 has a second output, through which the detected carrier frequency is fed to the input of the 35~ micro-controller 4. The band filters 20, 22 and 24 and the demodulator 26 are convertible by the micro-controller 4 J: ~
2 0 3 7 t~3 ~
;~ through the output 44 thereof in their centre frequencies ; between los kilohertz and 1~1 kilohertz. Further, the receive cup amplifier 27 can be switched on and off by the micro-controller 4 through the output 42 thereof. Thus, a voice signal is only connected to the receive cup 28 when the telegram exchange is terminated and the connection is established.
The transmitting section 3 contains, viewed in signal flow direction, a transmit cup 31 with a subsequent voice signal amplifier 32. The voice signal amplifier 32 has a transfer function with a pass band from 300 hertz to 3.4 kilohertz. The amplified and band-limited voice signal in base band position is transformed by a modulator 33 into a frequency-modulated signal. The modulator 33 generates ~;~ 15 a square-wave f.m. signal. This f.m. signal is fed to a , low-pass filter 34 and is then amplified in the transmitting amplifier 35. The low-pass filter 34 transforms the signal into a sinusoidal f.m. signal ~ containing no harmonics. The transmitting section 3 and `"~A 20 the receiving section 2 are combined in point 50 and are connected there with the mains coupler 1. The carrier frequency of the modulator 33 is adjusted by the micro-~ controller 4 through the output 47 thereof. Further, the ;~ transmitting amplifier 35 can be ~witched on and off by the micro-controller 4 through the output 46 thereof. ~hus, tl~ ~ the digital telegrams can be generated by the micro-controller 4 by switching the carrier frequency on and off.
The micro-controller 4 controls the complete -network~telephone and performs the following functions:
- switching transmitter and receiver on and off;
, ~ - executing channel assignment (conversion of transmitter~frequency and receiver filter to the respective channels);
- generating the dial signals;
~ reoognizing the own calling number, -. ~
~- 2 ~ 3 ~
- generating the bell signal and the ringing and busy signals.
~ `
Besides the inputs and outputs 42 to 47 of the micro-controller 4 described above, there is another input ; 41 for entries of the peripheral unit 5 to the micro-controller 4, and another output 48 for outputs of the micro-controller 4 to the peripheral unit 5.
- P~:
The peripheral unit 5 comprises a keyboard for generating the dialling information or other information, such as, for example, entry of a new own telephone number:
a hook contact for the information, whether the receiver has been lifted off or not; and a buzzer for generating the bell signal. In the present configuration with a block length of 4 bits for the telegram information "source of telegram", an arbitrary number from 1 to 9 can be entered ~ as telephone number of a network telephone. A maximum of : 9 users are thus possible in an in-house network. Larger numbers of users can be achieved by extending the block lengths of the telegram.
i, Referring now to Figure 2, there is shown the coupling between an internal house communication network through the power supply with the external public telephone ~; network. In the example shown, the internal house ;~ ~ communication network comprises the network telephones 65, 66 and 67 being connected with the in-house power supply.
As the network telephones can be connected to different pha~es of the house power network, the phases R, S and T
are bridged with respect to high frequency by a phase coupler 63. In order that conversations within a house cannot be tapped from outside, a carrier frequency blocking unit 64 is provided at the transition of the house network ..,~ .
to the external power distribution network. It is possible that house appliances, being connected to the in-house ~J~
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power supply as well, may generate a short-circuit to ground with respect to high freguencies of individual phases. Therefore, such house appliances must be provided with interference-suppressor filters 68, 69 and 70.
The transition from a house network to the public telephone network is accomplished by a network interface 62, which is connected to the in-house power supply, and to a cable terminal unit 60 comprising at least one master - 10 connection to the public telephone network. The cable terminal unit 60 comprises at least one hand set 61. With ~; such a configuration, an extension system is achieved.
., .
Figure 3 shows a diagrammatical block scheme of a 15 network interface. There is shown a network terminal 13 leading into the mains coupler l. At point 50 the receiving section 2 and the tran~mitting section 3 are connected to each other. The receiving and the J transmitting sections 3, 2 are acted upon by the micro-,, 20 controller 4 in the way as shown for the network telephones. For synchronization, the micro-controller 4 is supplied with the pulsing d.c. voltage from the mains coupler 1 through the input 45. The receiving section 2 and the transmitting section 3 lead into a hook circuit 80 25 being connected to an external adapter circuit 81 leading to an extension line 82. For transferring the dial information of the in-house communication method by means of transmission of information of the address in a digital telegram for an equal-rights user operation into the dial i~ 30 procedure of the public telephone network, the micro-!~ controller 4 controls a ralay driver 83 acting upon the external adapter circuit 81 and initiating there the 7~ required public dial procedure. For transferring the dial information from the public telephone network into the in-house communication network, the dial information is fed from the external adapter circuit 81 through the input 49 2~3~
to the micro-controller transforming such information into corresponding call telegrams.
; In another embodiment (not illustrated), voice transmission is effected in digital form. An A/D converter -is employed between the voice signal amplifier 32 and the modulator 33, and a D/A converter is located between the demodulator 26 and the amplifier 27. The modulated digital voice signal provided by the modulator 33 is generated by frequency conversion of the carrier frequency oscillation.
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THE IN-HOUSE POWER SUPPLY
~ he invention relates to a method and to a device for in-house voice and data communication, i. e.
transmission of voice and data signals, between communication terminals, in particular telephone-like devices, using at least two transmission channels, the in-house power supply lines being used as carrier for the transmission of information. Such communication systems with signalling of dialling forming in connection with a known private telephone system a small extension system ; without dedicated lines are known in the art from DE 37 07 310 C2 and DE 37 07 308 C2.
The communication systems described in the prior art referenced above comprise one central adapter unit and one or more exterior adapter units coupled to power supply lines. The central adapter unit also provides for ;~20 communication between the external public telephone network and the in-house communication network through a postal ~;~line transmission unit. To one exterior adapter unit is connected a respective normal extension phone set. In the exterior adapter unit, a hook switch splits the connection ~;~25 line in one carrier-frequency transmitting and receiving channel each having an adequate arrangement in the central adapter unit. Transmission of voice is effected by frequency modulation of the carrier frequency of the respective transmitting channel. Signalling of dialling is ef~ected over pilot-tone transmitters and receivers by means of selector relays, such that the establishment of a connection of one extension terminal with another one will take place over the central adapter unit.
A principle object of the invention is to provide a method allowing transmission of voice and data on the in-. .
, ~ '.' - . . ~ . . . . - ~ , .,; : : : , ,. . '~
:' ' ' ' , ' ::
2~3~ .i 7 house power supply lines with small expenditure, and to allow a direct connection of a user with another one of a possibly large number of users on the in~house network, `~ without a central exchange or a bus master being required.
~- 5 The method of the invention is characterised as a method for in-house voice and data communication through the in-house power supply, using at least two transmission channels, voice communication being effected by means of frequency modulation, wherein data communication between the communication terminals, in particular the information for the structure of the connections, is performed in digital form by means of pulse modulation, and data communication between the communication terminals through ; 15 the in-house power supply operating as a bus consisting of two channels is effected by a handshake procedure.
one transmission channel is assigned to the calling party, and a second transmission channel is ; 20 assigned to the called party. The transmission channels have respective frequencies of 109 kilohertz and 131 kilohertz, with a maximum frequency variation of ~F = 3.5 ~ kilohertz, and are assigned to the called user and the ~~ calling user respectively.
~ 25 :.., According to one aspect of the invention, digital ~ telegrams are generated by switching the carrier frequency -`, !, on and off, and the set of a telegram consists of four blocks with block lengths L1, L2, ~ and L4, such that in the first block a "start of telegram" identification is transmitted, and the three remaining blocks, the sequence of which is arbitrary but predetermined, contain the ~i information "type of telegram", "source of telegram" and 1 "destination of telegram", and, if necessary, a header ~ 35 block of length Lo is transmitted prior to the telegram. -20~ 4j 'i The cora of the invention consists in a method for in-house voice and data communication between communication terminals, in particular telephone-like devices, using the in-house power supply. communication is effected between terminals through at least two transmission channels and no ;~ central exchange, e.g. in the form of a central adapter installation is required. When limited to two transmission channels, the in-house power supply is adapted as a bus with two carrier-frequency channels. The method according to the invention provides that exchange of data is achieved in digital form by pulse modulation of the carrier, and - that transmission of voice is effected by frequency modulation. The digital data exchange, in particular for dial set-up of a connection, is performed by means of data telegrams. When dialling, a hand-shake method is applied, ^~ i.e. upon receiving a "call telegram" of a call the called device will respond by an "acknowledgement telegram". For carrying-out the method, a transmitting and a receiving channel are assigned to the calling and the called parties ~ 20 respectively following a predetermined scheme. This scheme `~I of assignment may consist, e.g. in that the calling party , has always the channel having higher frequency as ; transmitting channel, and the channel having lower ` frequency as receiving channel.
The telegrams have a definite structure. Thus, e.g., a telegram comprises four blocks of block lengths L~, and L4 bits. The block lengths may be different or identical. The block transmitted first always contains a start of telegram identification, e.g. for a block length ~; 30 4 bits, the code 1010. Ths three remaining blocks contain information on the type of telegram, the source address and 'l~ the destination address of the telegram~ The type of telegram determines the type of action to be taken. Under 1~ certain circumstances, it is necessary to transmit, prior j 35 to transmitting the telegram, a leader block of defined ~ length, in order to activate other, inoperative, users.
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The method according to the invention is, thereforei, particularly advantageous in that data transmission in the form of telegrams with acknowledgement allows for a simple structure of the ~ommunication link between two users without central exchange. In inoperative condition, the users are on the power supply which serves as a data bus, and can accept either one, or both, talker as well as listener functions. The calling user accepts automatically the role of the bus master when initiating a call. Thus a central exchange or control station, i.e. a dedicated bus master is not required. The method allows for a great flexibility with regard of possible future applications by defining further activities in the in~ormation block type of telegram.
; The device of the invention is characterised as a i ~evice for in~house voice and data communication between communication terminals through the in-house power supply, ~ voice communication being effected by means of frequency r", 20 modulation of the carrier frequency of the transmitting channel, said device comprising a mains coupler with power supply unit; a transmitting channel; a receiving channel;
and a micro-controller with a network controller performing control of the device and establishment of a communication 25 connection with other communication terminals by exchange of digital telegrams with acknowledgement operation and transmitting the telegrams by means of pulse modulation.
' 1 .
~`~ The device according to the invention, in the 30 following called a network telephone, contains a network coupler with integrated power supply unit, a receiver circuit, a transmitter circuit, a micro-controller and a ~; periphera} unit. It is particularly advantageous that each network telephone is provided with its own "intelligence", 35 because of the micro-controller. This micro-controller performs control of the complete network telephone, in ~4 ~ .
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- 2~373~j~
particular the micro-controller controls communication with other communication devices, which may be, in particular, other network telephones. By transmitting digital telegrams comprising the information l~start o~ telegram identification", "type of telegram", "destination of telegram" and "source of telegram", a simple and direct structure of the connections is possible. There will also not be reguired a central exchange, as the called device knows, through the information "destination of telegram", - 10 that it is addressed, and through the information "type of telegram" the order to be performed. Through the information "source of telegram", it is possible to perform , an acknowledgement of the call.
;~ Another advantageous embodiment of the invention can be seen under the term "collision csnsiderations~. As long as the network is not occupied, all users have equal access to the network. If the network is occupied, and a device tries to establish a second connection, it will obtain the information "busy". Collisions can only then occur when two devices try to establish a connection with ~;`j a period of time of approximately 20 ms. In this case, there are two possibilities:
a) The called party cannot respond because of a mutilated telegram. Both callers obtain a "busy" signal.
25b) The called party recognizes the incoming telegram from the first caller and can transmit now an answering telegram. If he has recognized correctly the call address, a communication is established, and the second caller obtains a "busy" signal.
30~
If the called party has not recognized correctly the call address, case a) will apply. Collisions on the in-house network can, thus, be resolved safely.
35~ Another advantage of the invention is that the device offers great flexibility~with regard to possible . ~
,~
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future applications by defining, e.g. further activities in the information block "type of telegram", or by extension of the telegrams by additional information blocks.
- The calling device occupies a transmitting channel and a receiving channel following an arbitrary, but predetermined scheme, which can be adapted such that the calling user occupies always the channel of higher ~10 frequency as transmitting channel, and the channel of lower :frequency ac receiving channel. This means that the called user automatically uses the lower frequency as a transmitting channel, and the higher frequency as a receiving channel. In an inoperative condition, all devices are listening, according to this scheme, on the higher frequency as receiving channel. The receiving and the transmitting channels of each device are, therefore, convertible with regard to frequency. The configuration scheme, once set-up together with the ~elegram system, 20 allows establishment of communication directly from one -device to another, without a central exchange with a pilot-r~tone dialling system being necessary.
In a simple way, an internal house communication system i8 achieved by using at least two devices according to the invention.
In the following, a preferred embodiment of the invention is described in more detail with reference to the appended drawings, wherein:
Figure 1 is a schematic block diagram of the network telephone of the invention;
Figure 2 is a schematic diagram of an in-house ~extension system on the in-house power supply; and : ~
. ~
2 l) 3 7 ~ ~ .
Figure 3 is a schematic diagram of a network interface for connection of the in-house telephone system to the external telephone system. -~
.
Referring now to Figure 1, there is shown ~ block ; diagram of a network telephone being intended for in-house use through the in-house power supply. The network telephone comprises five functional groups: a mains coupler ~- 1, a receiving section 2, a transmitting section 3, a micro-controller 4, and a peripheral unit 5. The mains coupler 1 is separated from the remaining components accommodated in a hand set, and is connected to the hand set over a four-wire cable. The mains coupler 1 contains a power transformer 10 with a rectifier. Mains voltage is ,~ 15 transformed down to 15 volts ~low voltage), and is then transformed into a pulsating d.c. voltage. The latter is then reduced in the hand set to the required operational d.c. voltages of 12 volts and 5 volts, and is stabilized.
The pulsating d.c. voltage is supplied to the micro-; 20 controller 4 over the input 45, as it contains the information on the zero passage of the mains voltage. This zero passage information is used for synchronization purposes of the telegram transmission and reception. The mains coupler 1 can be connected by a protective plug to mains 13.
The receiving section 2 of the network telephone consists of a chain of three band filters 20, 22 and 24, to each of which are added amplifiers 21, 23 and 25, ~t;~ ~ respectively. ~he filtered and amplified f.m. signal is ~ed to a demodulator 26. From there, the voice signal transformed back to band base position passes to an ~fo : amplifier 27 and is supplied to a receiver cup 28. The demodulator 26 has a second output, through which the detected carrier frequency is fed to the input of the 35~ micro-controller 4. The band filters 20, 22 and 24 and the demodulator 26 are convertible by the micro-controller 4 J: ~
2 0 3 7 t~3 ~
;~ through the output 44 thereof in their centre frequencies ; between los kilohertz and 1~1 kilohertz. Further, the receive cup amplifier 27 can be switched on and off by the micro-controller 4 through the output 42 thereof. Thus, a voice signal is only connected to the receive cup 28 when the telegram exchange is terminated and the connection is established.
The transmitting section 3 contains, viewed in signal flow direction, a transmit cup 31 with a subsequent voice signal amplifier 32. The voice signal amplifier 32 has a transfer function with a pass band from 300 hertz to 3.4 kilohertz. The amplified and band-limited voice signal in base band position is transformed by a modulator 33 into a frequency-modulated signal. The modulator 33 generates ~;~ 15 a square-wave f.m. signal. This f.m. signal is fed to a , low-pass filter 34 and is then amplified in the transmitting amplifier 35. The low-pass filter 34 transforms the signal into a sinusoidal f.m. signal ~ containing no harmonics. The transmitting section 3 and `"~A 20 the receiving section 2 are combined in point 50 and are connected there with the mains coupler 1. The carrier frequency of the modulator 33 is adjusted by the micro-~ controller 4 through the output 47 thereof. Further, the ;~ transmitting amplifier 35 can be ~witched on and off by the micro-controller 4 through the output 46 thereof. ~hus, tl~ ~ the digital telegrams can be generated by the micro-controller 4 by switching the carrier frequency on and off.
The micro-controller 4 controls the complete -network~telephone and performs the following functions:
- switching transmitter and receiver on and off;
, ~ - executing channel assignment (conversion of transmitter~frequency and receiver filter to the respective channels);
- generating the dial signals;
~ reoognizing the own calling number, -. ~
~- 2 ~ 3 ~
- generating the bell signal and the ringing and busy signals.
~ `
Besides the inputs and outputs 42 to 47 of the micro-controller 4 described above, there is another input ; 41 for entries of the peripheral unit 5 to the micro-controller 4, and another output 48 for outputs of the micro-controller 4 to the peripheral unit 5.
- P~:
The peripheral unit 5 comprises a keyboard for generating the dialling information or other information, such as, for example, entry of a new own telephone number:
a hook contact for the information, whether the receiver has been lifted off or not; and a buzzer for generating the bell signal. In the present configuration with a block length of 4 bits for the telegram information "source of telegram", an arbitrary number from 1 to 9 can be entered ~ as telephone number of a network telephone. A maximum of : 9 users are thus possible in an in-house network. Larger numbers of users can be achieved by extending the block lengths of the telegram.
i, Referring now to Figure 2, there is shown the coupling between an internal house communication network through the power supply with the external public telephone ~; network. In the example shown, the internal house ;~ ~ communication network comprises the network telephones 65, 66 and 67 being connected with the in-house power supply.
As the network telephones can be connected to different pha~es of the house power network, the phases R, S and T
are bridged with respect to high frequency by a phase coupler 63. In order that conversations within a house cannot be tapped from outside, a carrier frequency blocking unit 64 is provided at the transition of the house network ..,~ .
to the external power distribution network. It is possible that house appliances, being connected to the in-house ~J~
' :~.' : . , ', ' ', "' ' ' ' ' 3 7 ~
power supply as well, may generate a short-circuit to ground with respect to high freguencies of individual phases. Therefore, such house appliances must be provided with interference-suppressor filters 68, 69 and 70.
The transition from a house network to the public telephone network is accomplished by a network interface 62, which is connected to the in-house power supply, and to a cable terminal unit 60 comprising at least one master - 10 connection to the public telephone network. The cable terminal unit 60 comprises at least one hand set 61. With ~; such a configuration, an extension system is achieved.
., .
Figure 3 shows a diagrammatical block scheme of a 15 network interface. There is shown a network terminal 13 leading into the mains coupler l. At point 50 the receiving section 2 and the tran~mitting section 3 are connected to each other. The receiving and the J transmitting sections 3, 2 are acted upon by the micro-,, 20 controller 4 in the way as shown for the network telephones. For synchronization, the micro-controller 4 is supplied with the pulsing d.c. voltage from the mains coupler 1 through the input 45. The receiving section 2 and the transmitting section 3 lead into a hook circuit 80 25 being connected to an external adapter circuit 81 leading to an extension line 82. For transferring the dial information of the in-house communication method by means of transmission of information of the address in a digital telegram for an equal-rights user operation into the dial i~ 30 procedure of the public telephone network, the micro-!~ controller 4 controls a ralay driver 83 acting upon the external adapter circuit 81 and initiating there the 7~ required public dial procedure. For transferring the dial information from the public telephone network into the in-house communication network, the dial information is fed from the external adapter circuit 81 through the input 49 2~3~
to the micro-controller transforming such information into corresponding call telegrams.
; In another embodiment (not illustrated), voice transmission is effected in digital form. An A/D converter -is employed between the voice signal amplifier 32 and the modulator 33, and a D/A converter is located between the demodulator 26 and the amplifier 27. The modulated digital voice signal provided by the modulator 33 is generated by frequency conversion of the carrier frequency oscillation.
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Claims (18)
1. A method for in-house voice and data communication through an in-house power supply, using at least two transmission channels, voice communication being effected by means of frequency modulation, wherein data communication between the communication terminals, including information for the structure of the connections, is performed in digital form by means of pulse modulation, and data communication between same communication terminals through the in-house power supply operating as a bus comprising a plurality of channels is effected by a handshake procedure.
2. A method according to claim 1, wherein one transmission channel is assigned to the calling party, and a second transmission channel is assigned to the called party.
3. A method according to claim 2, wherein the transmission channels have frequencies of 109 kilohertz and 131 kilohertz, with a maximum frequency variation of .delta.F =
3.5 kilohertz, are used for signal transmission, and are assigned to the called user and the calling user respectively.
3.5 kilohertz, are used for signal transmission, and are assigned to the called user and the calling user respectively.
4. A method according to either of claims 1 or 2, wherein digital telegrams are generated by switching the carrier frequency on and off, and wherein the set of a telegram consists of four blocks with block lengths L1, L2, L5 and L4, such that in the first block a "start of telegram" identification is transmitted, and the three remaining blocks, the sequence of which is arbitrary but predetermined, contain the information "type of telegram", "source of telegram" and "destination of telegram", and, if necessary, a header block of length L0 is transmitted prior to the telegram.
5. A device for in-house voice and data communication between communication terminals through the in-house power supply, voice communication being effected by means of frequency modulation of the carrier frequency of the transmitting channel, said device comprising a mains coupler with power supply unit; a transmitting channel; a receiving channel; and a micro-controller with a network controller performing control of the device and establishment of a communication connection with other communication terminals by exchange of digital telegrams with acknowledgement operation and transmitting the telegrams by means of pulse modulation.
6. A device according to claim 5, wherein said digital telegram is generated by switching the carrier frequency of the respective transmitting channel on and off, whereby a telegram set is composed of four blocks with block lengths of L1, L2, L3 and L4 is produced; the front block containing a "start of telegram" identification; the remaining three blocks the sequence of which is arbitrary but predetermined containing the information "type of telegram", "source of telegram" and "destination of telegram"; and, if necessary, there is a header block of length, L0 in front of the telegram.
7. A device according to claim 6, wherein said header block has a length of 24 bits, which are set to logic 1; and the telegram has a length of 16 bits, the four telegram blocks having each a length of 4 bits.
8. A device according to claim 6, wherein said receiving channel comprises band filters connected to respective amplifiers; the signal resulting therefrom is fed to a demodulator; digital telegrams are fed directly to the micro-controller over a line; and voice signals transformed back into the base band position are fed to the receiver cup through an amplifier.
9. A device according to claim 6, wherein the transmitting channel, viewed in signal flowing direction, is composed of the transmit cup, a subsequent first transmit amplifier, a modulator performing the conversion of the voice signal into the carrier frequency position, a subsequent low-pass filter and a second transmit amplifier, which can be switched on and off by the micro-controller over a line.
10. A device according to claims 8 and 9, wherein the band filters, the demodulator of the receiving channel and the modulator of the transmitting channel can be converted by the micro-controller over two lines in their frequency, and are operated as calling party corresponding to a transmit centre frequency of 131 kilohertz and to a receive centre frequency of 109 kilohertz, or as called party corresponding to a transmit centre frequency of 109 kilohertz and to a receive centre frequency of 131 kilohertz.
11. A device according to claim 9, wherein the micro-controller comprises inputs for the telegram recognition, keyboard inclusive receiver contact, zero passage recognition of the mains voltage; and outputs for the receiver on/off, buzzer, conversion receiver frequency, conversion transmitter frequency and transmitter on/off;
whereby said micro-controller controls the complete device, and performs the functions of switching the transmit amplifier and the receive amplifier on and off, executing the channel assignment, generating dial signals, recognizing the own calling number, and generating the bell signal including ringing or busy signals, respectively.
whereby said micro-controller controls the complete device, and performs the functions of switching the transmit amplifier and the receive amplifier on and off, executing the channel assignment, generating dial signals, recognizing the own calling number, and generating the bell signal including ringing or busy signals, respectively.
12. A device according to either of claims 9 or 11, wherein in the modulator a square-wave frequency-modulated output voltage is converted by a low-pass filter behind a transmit amplifier into a sinusoidal output voltage of the respective transmit carrier frequency, the carrier frequency being determined by the micro-controller at the modulator through the output.
13. A device according to claim 12, wherein transmitting and receiving channels are combined, and the signals transmitted over a band-pass filter in a plug power supply unit by means of an inductive h.f. coupling to the power network; a mains transformer being arranged in said plug power supply unit with a rectifier generating a pulsating d.c. voltage being smoothened and stabilized to the required operating voltages, the pulsating d.c. voltage being, further, fed to said micro-controller for determination of zero passage, in order to allow synchronization for data transmission with said pulse modulation.
14. A device according to claim 13, wherein transmission of a call by means of pulse modulation is effected by switching the transmit amplifier on and off by the micro-controller through an output.
15. A device according to claim 13, wherein recognition of a call in the micro-controller is effected by switching the data signals off following the cycle of zero passages of the mains frequency, said data signals being fed to the micro-controller from said demodulator through an input.
16. A device according to any of claims 5 to 15, wherein by coupling the power supply network and at least one network telephone over an interface to a cable terminal unit, a transition between the in-house network and the external telephone network is accomplished, and an extension system is achieved.
17. A device according to claim 16, wherein the interface comprises a mains coupling unit including a power supply unit, a receiving channel, a transmitting channel, a micro-controller, a hook circuit, an external adapter circuit and a relay driver; the mains coupling unit being connected in point with the transmitting channel and the receiving channel, whereby said micro-controller performs control of the device, performs through the input the zero passage detection, and controls the receiving and transmitting sections, such that transmitting and receiving channels are combined to a hook circuit, and that said hook circuit is connected with an external adapter circuit being lead over a parallel line to a cable transmission unit forming the terminal of the external public telephone network; dial information being fed from the in-house network into the public network by the micro-controller through the output on the relay driver initiating the usual dial procedure in the external adapter circuit when establishing a connection; whereas in the other dial direction, said dial information is fed from said external adapter circuit through an input to the micro-controller thereby transforming such information into a corresponding telegram.
18. A device according to any of claims 5 to 17, wherein voice transmission is effected in digital form; an A/D converter being disposed between the voice signal amplifier and the modulator, and a D/A converter is disposed between the demodulator and the amplifier, a modulated digital voice signal provided by the modulator being generated by frequency conversion of the carrier frequency oscillation.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP4008023.4 | 1990-03-09 | ||
| DE4008023A DE4008023A1 (en) | 1990-03-09 | 1990-03-09 | METHOD FOR IN-HOUSE VOICE AND DATA COMMUNICATION VIA THE IN-HOUSE POWER SUPPLY NETWORK |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2037557A1 true CA2037557A1 (en) | 1991-09-10 |
Family
ID=6402109
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002037557A Abandoned CA2037557A1 (en) | 1990-03-09 | 1991-03-05 | Method for in-house voice and data communication through the in-house power supply |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0445375A1 (en) |
| JP (1) | JPH04220023A (en) |
| KR (1) | KR910017755A (en) |
| AU (1) | AU7004991A (en) |
| CA (1) | CA2037557A1 (en) |
| DE (1) | DE4008023A1 (en) |
| FI (1) | FI911169A (en) |
| NO (1) | NO905446L (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6633228B1 (en) | 1999-02-22 | 2003-10-14 | Siemens Aktiengesellschaft | Communication system for simultaneous two-channel transmission of data between subscribers |
Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE9401402U1 (en) * | 1993-03-26 | 1994-03-31 | Siemens Ag | Connection adapter for mains-powered and bus-controlled devices |
| JPH07273695A (en) * | 1994-01-24 | 1995-10-20 | Yair Maryanka | Transmission of voice,music,image and data through dc conductor |
| NL9400239A (en) * | 1994-02-17 | 1995-10-02 | Grid Telecom Systems Bv | Home telephone system. |
| DE19604198A1 (en) * | 1996-02-06 | 1997-08-07 | David Horst | Computer data transmission method using lighting system wiring |
| IT1284281B1 (en) * | 1996-02-21 | 1998-05-18 | Elesia Srl | SYSTEM FOR DATA TRANSMISSION, REMOTE SENSING, REMOTE CONTROLS, REMOTE READING AND SIMILAR, PARTICULARLY SUITABLE FOR DISTRIBUTION LINES |
| DE19635163C2 (en) * | 1996-08-30 | 1999-12-09 | Bosch Gmbh Robert | Remote electrical control device for low voltage electrical devices |
| DE19636031A1 (en) * | 1996-09-05 | 1998-03-12 | Varchmin J Uwe Prof Dr Ing | Communication system for explosive detonation |
| DE19640223C2 (en) | 1996-09-30 | 1998-10-22 | Siemens Ag | Method for operating a communication and / or control system and communication and / or control system |
| DE19704216A1 (en) * | 1997-02-05 | 1998-08-06 | Deutsche Telekom Ag | Monitoring device for mains-operated household appliances |
| DE10061585B4 (en) * | 2000-12-11 | 2004-01-29 | Siemens Ag | Arrangement and method for data communication in a power distribution network |
| DE10061587B4 (en) * | 2000-12-11 | 2004-02-12 | Siemens Ag | Arrangement and method for data communication in a power distribution network |
| DE10063675C1 (en) | 2000-12-20 | 2002-06-20 | Siemens Ag | Method and device for transmitting data on at least one electrical power supply line |
| DE10121048A1 (en) * | 2001-04-28 | 2002-10-31 | Abb Patent Gmbh | Arrangement for propagating information via mains has data transmitter with transmission protocol comparator and error assessor connected to mains via transformer/modulator |
| DE10242239A1 (en) * | 2002-04-26 | 2004-03-25 | Eichhoff Gmbh | Domestic device, e.g. washing machine, dishwasher, heating system or similar, has coupling point for powerline signals provided at suppression filter immediately on mains side of suppression capacitor |
| DE10218863B4 (en) * | 2002-05-21 | 2010-04-08 | Eichhoff Gmbh | Domestic appliance and device for installation in a domestic appliance |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2529386C3 (en) * | 1975-07-02 | 1980-04-03 | Institut Fuer Rundfunktechnik Gmbh, 8000 Muenchen | Method for the additional transmission of data, remote control signals, etc. via an FM stereo radio transmitter |
| US4479033A (en) * | 1982-03-29 | 1984-10-23 | Astech, Inc. | Telephone extension system utilizing power line carrier signals |
| DE3320397A1 (en) * | 1983-06-06 | 1984-12-06 | Siemens AG, 1000 Berlin und 8000 München | ARRANGEMENT FOR THE TRANSFERABLE TRANSMISSION OF SOUND SIGNALS |
| DE3407310A1 (en) * | 1984-02-24 | 1985-09-12 | Siemens AG, 1000 Berlin und 8000 München | Dedicated-line-free communications system (small PBX system with dial and call signalling via the power supply mains) |
| DE3407308A1 (en) * | 1984-02-24 | 1985-09-12 | Siemens AG, 1000 Berlin und 8000 München | Dedicated-line-free communications system (small PBX system with an adapter connection to the power supply mains) |
| JPH0771069B2 (en) * | 1987-12-24 | 1995-07-31 | 日本放送協会 | Digital code transmission method for AM radio |
| US4996709A (en) * | 1988-05-12 | 1991-02-26 | Tandy Corporation | Intercom telephone |
-
1990
- 1990-03-09 DE DE4008023A patent/DE4008023A1/en active Granted
- 1990-11-29 EP EP90122799A patent/EP0445375A1/en not_active Withdrawn
- 1990-12-18 NO NO90905446A patent/NO905446L/en unknown
-
1991
- 1991-01-29 AU AU70049/91A patent/AU7004991A/en not_active Abandoned
- 1991-02-21 KR KR1019910002762A patent/KR910017755A/en not_active Application Discontinuation
- 1991-03-05 CA CA002037557A patent/CA2037557A1/en not_active Abandoned
- 1991-03-07 JP JP3065303A patent/JPH04220023A/en active Pending
- 1991-03-08 FI FI911169A patent/FI911169A/en unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6633228B1 (en) | 1999-02-22 | 2003-10-14 | Siemens Aktiengesellschaft | Communication system for simultaneous two-channel transmission of data between subscribers |
Also Published As
| Publication number | Publication date |
|---|---|
| FI911169A (en) | 1991-09-10 |
| NO905446D0 (en) | 1990-12-18 |
| KR910017755A (en) | 1991-11-05 |
| NO905446L (en) | 1991-09-10 |
| EP0445375A1 (en) | 1991-09-11 |
| DE4008023A1 (en) | 1991-09-12 |
| DE4008023C2 (en) | 1992-03-12 |
| JPH04220023A (en) | 1992-08-11 |
| AU7004991A (en) | 1991-09-12 |
| FI911169A0 (en) | 1991-03-08 |
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Legal Events
| Date | Code | Title | Description |
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| FZDE | Discontinued |