Digital added main line system

• US 5,459,729 A
• Filed: 07/25/1989
• Issued: 10/17/1995
• Est. Priority Date: 07/25/1989
• Status: Expired due to Fees

• Current Assignee: Terayon Communications Systems Incorporated (Motorola Solutions, Inc.)
• Original Assignee: Raychem Corporation (TE Connectivity Limited)
• Inventors: Bliven, David C.
• Primary Examiner(s): Kizou, Hassan
• Application Number:
  US07/385,610
• Time in Patent Office: 2,275 Days
• Field of Search: 370/112, 370/118, 370/84, 370/109, 370/7, 370/95.3, 370/56, 370/57, 375/122, 375/24, 375/240, 375/286, 375/288, 379/333, 379/334, 379/387, 379/399, 379/406, 379/410
• US Class Current: 370/465
• CPC Class Codes: H04J 3/18 using frequency compression and subsequent expansion of the individual signals
• CPC Class Codes: H04M 11/068 using time division multiplex techniques; integrated services digital networks H04Q11/0428
• CPC Class Codes: H04Q 11/0428 Integrated services digital network, i.e. systems for transmission of different types of digitised signals, e.g. speech, data, telecentral, television signals
• CPC Class Codes: H04Q 11/0471 Terminal access circuits
• CPC Class Codes: H04Q 2213/034 Codec; PCM compression
• CPC Class Codes: H04Q 2213/09 Subscriber related equipment; Analog terminal
• CPC Class Codes: H04Q 2213/099 Loop multiplexer (not ISDN BRI/PRI; not 381), e.g. loop splitter
• CPC Class Codes: H04Q 2213/13034 A/D conversion, code compression/expansion
• CPC Class Codes: H04Q 2213/1305 Software aspects
• CPC Class Codes: H04Q 2213/1308 Power supply
• CPC Class Codes: H04Q 2213/13106 Microprocessor, CPU
• CPC Class Codes: H04Q 2213/13174 Data transmission, file transfer
• CPC Class Codes: H04Q 2213/1319 Amplifier, attenuation circuit, echo suppressor
• CPC Class Codes: H04Q 2213/13199 Modem, modulation
• CPC Class Codes: H04Q 2213/13204 Protocols
• CPC Class Codes: H04Q 2213/13208 Inverse multiplexing, channel bonding, e.g. TSSI aspects
• CPC Class Codes: H04Q 2213/13209 ISDN
• CPC Class Codes: H04Q 2213/13216 Code signals, frame structure
• CPC Class Codes: H04Q 2213/13292 Time division multiplexing, TDM
• CPC Class Codes: H04Q 2213/13297 Coupling different rates in TDM systems, data rate adaptation
• CPC Class Codes: H04Q 2213/1332 : Logic circuits
• CPC Class Codes: H04Q 2213/13322 : Integrated circuits
• CPC Class Codes: H04Q 2213/13367 : Hierarchical multiplexing, add-drop multiplexing
• CPC Class Codes: H04Q 2213/18 : Ringing
• CPC Class Codes: H04Q 2213/204 : ISDN protocol; ISO 7

Abstract

A method and apparatus for transmitting and receiving multiple telephone transmission signals over a single twisted pair. An analog signal from a local switching station is converted to an 80 kbits/sec signal for transmission over a twisted pair. A remote terminal converts the 80 kbits/sec signal back into a conventional analog signal for use in conventional telephone, facsimile or other related equipment.

Claims

1. A digital added main line comprising:

a) a remote terminal for use at a subscriber location, said remote terminal comprising;

i) a remote terminal ISDN echo cancellation integrated circuit for converting digital quaternary signals on a twisted pair line to binary signals and converting binary signals to quaternary signals for transmission over said twisted pair line;

ii) a remote terminal ISDN communications controller integrated circuit coupled to said remote terminal ISDN echo cancellation circuit for adding and removing control information to and from a data stream from and to said remote terminal ISDN echo cancellation circuit; and

iii) a remote terminal subscriber interface codac filter integrated circuit coupled to said remote terminal ISDN communications controller circuit for converting binary signals from and to said remote terminal ISDN echo cancellation circuit to and from at least two analog signals for use in subscriber equipment; and

b) a master comprising;

i) a master subscriber interface codac filter (SICOFI) integrated circuit for conversion of analog signals at a local switch to and from digital binary signals;

ii) a master ISDN communications controller integrated circuit coupled to said master SICOFI for adding and removing control information to and from a data stream from said SICOFI; and

iii) a master ISDN echo cancellation integrated circuit coupled to said master ISDN communications controller for conversion of digital binary signals to and from quaternary signals for transmission over said twisted pair.

2. A digital added main line as recited in claim 1 wherein said remote terminal is located at a terminus of said twisted pair at a home or office and said master is located at a telephone company switch.

3. A digital added main line as recited in claim 1 wherein said remote terminal and master ISDN echo cancellation circuits are adapted to transmit and receive substantially 80 ksymbols/sec signals.

4. A digital added main line as recited in claim 1 wherein said remote terminal and master ISDN communications controllers are adapted to transmit and receive substantially 160 kbits/sec signals.

5. In a system for transmission of a single analog signal from a telephone company location to a subscriber location over a twisted pair, a method of converting said system to a system for multiple signal transmission over said twisted pair comprising:

a) installing master equipment at said telephone company location, said master equipment;

i) inputting multiple incoming telephone company analog signals from telephone company equipment and outputting multiple outgoing telephone company analog signals to said telephone company equipment;

ii) converting said multiple incoming telephone company analog signals to a multiplexed outgoing 2B1Q signal and converting a multiplexed incoming 2B1Q signal to said multiple outgoing telephone company analog signals; and

iii) transmitting said multiplexed outgoing 2B1Q signal over said twisted pair to said subscriber location and receiving said multiplexed incoming 2B1Q signal; and

b) installing a remote terminal at said subscriber location, said remote terminal;

i) inputting said multiplexed outgoing 2B1Q signal-from said twisted pair and outputting said multiplexed incoming 2B1Q signal on said twisted pair;

ii) converting said multiplexed outgoing 2B1Q signal to multiple outgoing subscriber analog signals and converting multiple incoming subscriber analog signals to said multiplexed incoming 2B1Q signal; and

iii) transmitting said multiple outgoing subscriber analog signals to subscriber equipment and receiving said multiple incoming subscriber analog signals from said subscriber equipment.

6. The method as recited in claim 5 wherein said twisted pair has a length greater than 1,000 feet.

7. The method as recited in claim 5 wherein said twisted pair has a length greater than about 15,000 feet.

8. The method as recited in claim 5, said remote terminal further converting said multiple outgoing subscriber analog signals from a four-wire format to a two-wire format and converting said multiple incoming subscriber analog signals from a two-wire format to a four-wire format.