MXPA97007157A - Voice and da communications - Google Patents

Abstract

The present invention relates to a method and apparatus (200) for converting an analog speech channel signal to a 4-wire digital signal into a single 2-wire signal that can be transferred over a single transected line (205). In aspect, the method comprises the steps of converting the analog speech channel signal into a first binary signal, converting the digital signal of 4 wires into a second binary signal, combining the first binary signal and the second signal into a digital binary signal. higher speed and converting the higher speed binary signal into a 2 wire digital signal that can be transmitted to another location on a single line in transected pair. In another aspect, the method comprises the steps of converting a digital signal of 2 wires to a higher speed binary signal, separating a first binary signal from a higher speed binary signal and converting the first binary signal into a voice channel signal. analog and converting a second binary signal into a 4-wire digital signal. The apparatus (200) includes a positive digital remote voice data terminal (203) easily installed and a positive digital voice data central office terminal (201). The apparatus can provide a gain of 3 to 1 pairs by multiplexing signals representing analog voice telephone signals and 4-wire digital data signals

Description

VOICE AND DATA COMMUNICATIONS Most electronic data processing equipment, eg, telephones, computers and facsimile machines, makes use of 4-wire digital signals (often referred to as digital data services or North American SDDs). ). The transmission of these signals requires four wires that do not have abrupt changes in impedance. For example, if telephone lines are available they should be used for 4-wire digital services, they should be tested and modified (often referred to as Class C3 data conditioning). This is a serious disadvantage, even if four telephone lines are available, which is not always the case. In addition, repeaters are often needed. For example, a normal 4-wire signal is a bipolar signal at a transmission rate of up to 56 kbps. These signals usually need a repeater if the extension of the line exceeds 3000 to 3650 meters. An additional difficulty is that it is difficult to combine the conventional analogue telephone service (STAC) with the digital 4-wire service. We have discovered, in accordance with the present invention, how to transfer a 4-wire digital signal and an analog voice channel signal onto a single 2-wire cable, for example a single twisted pair. Therefore, in a first preferred aspect, that invention provides a method for converting an analog voice signal and a 4 wire digital signal into a single signal that can be transferred over a single twisted pair line, the method comprising the steps of : to. converting the analog voice channel signal into a first binary signal; b. converting the 4-wire digital signal into a second binary signal; c. combining the first binary signal and the second binary signal in a higher-level binary signal; and d. convert the higher-level binary signal into a 2-wire digital signal. In a second preferred aspect, this invention provides a method for transferring an analog voice channel signal and a 4 wire digital signal from a first location to a second location on a single stranded line between the locations, the method comprising : e. in one of the locations, converting an analog voice channel signal and a 4 wire digital signal into a 2 wire digital signal by the method of the first aspect of the invention; F. transfer the 2-wire digital signal from step (e) onto the single line of the twisted pair to the other location; and g. in the other location, i. convert the 2-wire digital signal from step (f) to a higher-level binary signal, ii. separating a first binary signal and a second binary signal from a higher-level binary signal produced in step (g (i)), and ii. converting the first binary signal obtained in step (g (ii)) into an analog voice channel signal and converting the second binary signal obtained in step (g (ü)) into a 4-wire digital signal. Normally, one of the places will be a location in the telephone company and the other location will be a customer establishment. In most cases, step (g) will recreate the analog and digital signals that were converted into steps (a) and (b), and they will do so through the same higher-level binary signal, the first binary signal and the second binary signal. However, the invention includes the possibility that one or more of the signals in step (g) refer to, but are not identical to, the corresponding signal in steps (a) to (d). In most cases, steps (e), (f) and (g) will be carried out in both places, so that the 2-wire digital signals are transferred in both directions below the twisted pair. In a third preferred aspect, the invention provides the apparatus which is suitable for use in the method of the first preferred aspect of the invention and which comprises: 1. means for receiving a voice signal of analog channel; 2. means to receive a dig ital signal of 4 wires; 3. means for converting the analog voice channel signal into a first binary signal; 4. means for converting the 4-wire digital signal into a binary signal; Means for combining the first binary signal and the second binary signal in a higher-level binary signal; 6. means for converting the top-level binary signal into a 2-wire digital format; and 7. means for transferring the 2-wire digital signal to a single twisted pair line. In a fourth preferred aspect, the invention provides the apparatus which is suitable for use in the other location in the method of the second preferred aspect of the invention and which comprises: 1. means for receiving a 2-wire digital signal; 2. means for converting the 2-wire digital signal into a higher-level binary signal; 3. means for separating a first binary signal and a second binary signal from the higher-level binary signal; 4. means for converting the first binary signal into an analog voice channel signal; and 5. means for converting the second binary signal into a 4-wire digital signal. In a fifth preferred aspect, the invention provides the apparatus which combines the apparatus of the third and fourth aspects of the invention and which, therefore, is suitable for use in both applications when the signals are transferred in both directions.

The 4-wire digital signal that is converted by the method of the invention can be, for example, a bipolar signal from a Digital Data Service (SDD) channel. The digital signal may include a video, data or voice signal, usually at a signaling rate of 2.4 kbps, 4.8 kbps, 9.6 kbps, 19.2 kbps, 56 kbps or 64 kbps. The analog voice channel signal is usually a voice signal, but may be another analog signal. In one embodiment, the higher speed binary signal has a bit rate of 256 kbps and the digital wire signal has a bit rate of 160 kbps. In another mode, the 2-wire digital signal has a bit rate of 288 kbps, 416 kbps, 784 kbps or 1 168 kbps. The 2 wire digital signal preferably has a 2 BI Q format or a 4B3T format. The invention is particularly useful when the twisted pair is at least 5,486 meters long and comprises wires of different calibers, since such wires are particularly difficult to use as part of a conventional 4-wire system. Because it is highly desirable that a conventional telephone link be available and the system malfunction, the invention preferably includes means for transferring the analog voice channel signal directly to the twisted pair telephone line. The specific embodiments of the invention will now be described by reference to the drawings. Figure 1 is a block diagram for a known 4-wire SDD circuit deployed over a local cycle l between a central office 12 and a property of a customer 14 is a local cycle of 4 wires 16. In the central office 12 , the conventional 4 wire SDD is coupled to the T 1 22 installations, and includes a digital switch (or cross connection) 24 and a channel bank 26. In North America, a conventional channel bank generally contains 24 channels and a bank conventional channel in Europe generally contains 30 channels. The channel bank may also include a multiplicity of office channels / data ports (UCO / PD) unit 34 to provide data signals to the local 4-wire cycles. A conventional channel bank can be a bank of channels D4. The 4-wire local cycle 16 between the UCO / PD 34, in the central office 12, and the data service unit / channel service unit (USD / USC) 38, in the client's property 14, includes two pairs braided 36, with each twisted pair comprising two wires. The 4-wire local cycle 16 also includes repeaters 18. The repeaters 18 are placed in the 4-wire local cycle 16 about every 10-13 kft of the line extension to regulate the bipolar digital pulses. The number of repeaters 18 placed in the local cycle of 4 wires 26 depends on the length or total length of the line. In the client's property 14, the 4 wire SDD includes a USD / USC 38, a line 28 interface and a data terminal equipment (ETD) 32. The USC terminates the digital circuit in the client's premises and performs functions such as line conditioning, testing of retro-circuit, signal regeneration and monitoring of the incoming digital signal to detect variations of rules that regulate the transmission of data in the digital installation of 4 wires. The USD / USC 38 combined converts the bipolar data format of the 4-wire local circuit 16 into a format such as RS-23C or V.35 for use in the DTE 32. k The USC / USC 38 also converts the DTE signal 32 in the bipolar data format for use in the digital installation of 4 wires. In one embodiment of the invention, the positive 4-wire voice SDD supplies an SDD signal and a voice channel from a central office of the telephone company to a customer's premises on a single twisted pair of telephone wires. Figure 2 is a block diagram for a system of SDD 4 wire 200 positive voice according to the invention. The 200 SDD system of 4 positive voice wires includes a terminal unit 201 of the positive digital voice data center (TOC DD Positive VF) (eg, line card) at a location 12 in the head office and a positive digital voice remote data service terminal (TR DD Positive VF) 203 in a customer premises 14. ROC DD Positive VF 201 receives and transmits analog VF signals via lines 205 and 4-wire SDD signals via lines 207. TR DD Positive VF 203 receives and transmits analog telephone signals via line 213 from and to telephone 211. TR DD Positive VF 203 also receives and transmits data signals from ETD 221 via USD / USC 219 via lines 217 USD / USC 219 converts 4-wire data signals into a signal compatible with DTE 221. The compatible signal includes RS-232C, V.35 and others. TOC DD Positive VF 201 and TR DD Positive VF 203 are preferably removable units that can be easily installed in the telephone company and customer locations, respectively. Between the Positive DD TOC of VF 201 and the TR DD Positive of VF 203 there is a digital subscriber line 204 which is a single twisted pair telephone line. The digital subscriber line 204 transmits multiplexed digital data through the single twisted pair at 160 kbps in a 2BIQ data format, without the use of repeaters, for a normal 10 kft mixed gauge line extension. Alternatively, the digital data format can be 4B3T and others. Figure 3 illustrates a block diagram of a VF Positive DD TOC 201 according to the invention. The Positive DD TOC of VF 201 includes a digital subscriber line transformer (LSD Xfmr) 31, an ISDN Quaternary Echo Cancellation Circuit 303 (CCEI), an ISDN communication controller circuit 305 (CCI), a microprocessor 307, an integrated circuit of the client 309, a filter 301 encoder-decoder (CODEC), a digital data service transceiver (SDD-B) 313, a hybrid transformer (Hybr. Xfmr) 315, data transformers (Xfmr data ( s)) 317, 319, among other elements. 4-wire outgoing SDD signals (CO SDD Rcv) enter Xfmr 317 data via lines 321 from a bank of channels in the central office. Xfmr 317 data and associated resistive elements (not shown) isolate, condition and equalize the impedance to 4 wire SDD signals for use in SDD-B 313. 4 wire outgoing SDD signals from Xfmr 317 data enter SDD -B 313 via lines 325. The SDD-B 313 performs the clock recovery and data formation operations selected. In particular, SDD-B 313 retrieves a clock signal (Clk) from the signal of 4 outgoing wires transmitted from Xfmr data 317 to be used by an integrated circuit of a client 309 and other circuit elements via line 329. The signal The clock is preferably at a signal rate of 56 kHz from a dedicated 56 kbps SDD or a switched 56 kbps service. The SDD-B 313 also converts the 4-wire output signal from the Xfmr 317 Data from the bipolar signal into a unipolar binary TTL signal defined by D + and its inversion D- to be used in the customer's integrated circuit 309 via the 331 lines The signals D + and D- also provide certain aspects of monitoring and correction of errors and the like. The outgoing analog signals such as voice and the like leave a STAC interface circuit of two wires from the central office via the lines 205 and enter a hybrid transformer 315. The hybrid transformer 315 isolates, conditions, equalizes the impedance and separates the outgoing analog signals into address signals sent and received for transmission to the CODEC filter 31 1 on the lines 349. The hybrid transformer 315 also converts the outgoing analog signals from a 2-wire format into a 4-wire format. The CODEC 31 1 filter converts the analog signals received from the hybrid transformer 315 into a digital PCM encoded signal using a sampling rate of 8, 000 times per second at 8 bits per sample. (The CODEC 31 1 filter also converts the PCM encoded digital signal into an analog signal in the reverse direction). The encoded dig ital signal is output from the CODEC 31 1 filter as a unipolar TTL binary signal defined by D + D- via the lines 353. The D + and D- signals also provide aspects such as monitoring, error correction and the like. The CO DEC filter 31 1 receives a clock signal (Clk) of 64 kHz via line 351 from the integrated circuit of the client 309. The clock signal can be derived from the synchronization clock signal captured from any source clock in the central office.

The integrated circuit of the client 309 provides aspects of handling and control of selected data time. The client integrated circuit 309 is typically an application-specific integrated circuit (CISA) such as a gate arrangement, a programmable field gate arrangement, or the like. In one embodiment, the customer's integrated circuit 309 is a Programmable Gate Arrangement in 300 Series Xilinx, however, other types of integrated circuit (s) and the like may also be used. The integrated circuit of the client 309 uses a closed phase cycle (CFC) to synchronize the clock (Clk) from the SDD-B 313 with its internal clocks. The customer's integrated circuit receives the 56 kHz clock signal from the SDD-B 313, divides the clock signal 56 Hz down to an 800 Hz clock signal and increases the 800 Hz clock signal to provide another selected clock frequencies in the form of a two-phase CFC configuration. For example, a first CFC introduces the 800 Hz signal and outputs a 512 kHz signal a second CFC introduces the 512 kHz signal outputs a 15.360 MHz signal. The 512 kHz clock introduces the CCI 305 via the 334 line. 1360 MHz clock the 512 kHz clock enters the CCI 303 via the line 336. The CFC configuration provides a clock signal at a 64 kHz rate also for use by the CODEC filter 311. The client integrated circuit 309 also uses the 64 kHz clock signal to construct the D + and D- signals that correspond to the CODEC 311 and SDD-B 313 filter signals in two 64 kbps data signals. The two 64 kbps data signals are multiplexed together with two other 64 kbps signals that correspond to a control and information channel (C and I), and a monitor channel. The total bit rate of the output signal of the four 64 kbps signals is added to 256 kbps, a corresponding incoming signal is also added to 256 kbps, thus requiring the use of the 512 kHz clock signal for synchronization. The output signal is "alternately" bidirectionally at a transmission speed of 512 kbps, and enters the CCI 305 via line 333. The output signal enters the CCI 305 arranged as 8 data characters of a first channel, 8 characters of data of a second channel, 8 characters of control and information data (C and I) and 8 characters of monitor signal data and then repeated in the other direction, allowing substantially simultaneous transmission / reception of the voice signals and digitized data signals. The CCI 305 converts the data stream of the integrated circuit of the client 309 into two binary TTL signals of unidirectional 256 kbps going to, and from, the CCEI 303. The CCI 305 operates a clock signal (CLK) to, for example , 512 kHz and a frame control signal (SCM) to, for example, 8 kHz. The CLK and SCM are provided from the integrated circuit of the client 309 via line 334. The data of the monitor, ring data and other data which the microprocessor 307 registers, are made available for the microprocessor 307 via lines 337 and 335 . ÍECQ 303 converts the 256 kbps binary signals it receives from the CCI 305 via line 341 to an outgoing 2BIQ data signal at 160 kbps. The CCEI 303 sends the outgoing data signal via line 343 in LSD Xfmr 301 which conditions and equalizes the impedance of the data signals for transmission over the digital subscriber line 204. The extension of the digital subscriber line 204 can be up to 18 kft of lines of braided parts of 24/26 gauge normally mixed without the use of any repeaters or similar. In wire sizes larger than 24/26 gauge, the extension can be up to 33 kft and even larger. The incoming signals from the digital subscriber line 204 in the Positive DD TOC of VF 201 are processed in a similar but inverse method as the output signals described above. In particular, a 2BIQ signal enters the LSD transformer 301 via lines 204 which isolates, conditions and equalizes the impedance of the 160 Kbps 2BIQ signal for use in CCEI 33. The 160 Kbps 2BIQ signal enters CCEI 303 via line 343. The CCEI 303 converts the 2BIQ signal into a binary signal to a transmission rate of 256 kbps for use in the CCI 305 via line 342. The CCI 305 sends data in the form of four 8-character words to the integrated circuit of the client 309 on the line 333. The integrated circuit of the client 309 separates the four 8-character words in binary TTL signals that correspond to the 4-wire SDD signal, the analog voice signal, the C and I signal, and the monitor signal. The 4-wire SDD binary TTL is transferred from the customer's integrated circuit 309 to the SD3 transceiver 313 via the 331 lines. The transducer 313 of SD D converts the binary TTL signals into the 4-wire SDD signal and transmits the 4-wire SDD signal via the lines 327 to the data transformer 319 at the desired SDD secondary rate. The SDD signals from 4 incoming wires leave the data transformer 319 via lines 323 to channel bank 219 (Fig. 2). A binary TTL signal representing the analog voice signal enters the CODEC filter 31 1 via lines 353 as D + and D- of the customer integrated circuit 309. The CODEC filter 31 1 converts the binary TTL data signal in a voice signal to a loop for transmission via the lines 349 to the hybrid transformer 315. The hybrid transformer 315 conditions the analog voice signal and transmits the analog voice signal conditioned via the line 205 to the channel bank 219 (FIG. ). Figure 4 illustrates a diagram of TR DD Positive VF 203 according to the invention. The TR DD Positive of VF 203 includes elements of the system such as a digital subscriber line processor (KS L Xfmr) 401, a CCEI 403, a CC I 405, a customer integrated circuit 407, a CODEC 409 filter, an SDD transceiver (SDD-B) 41 1, a subscriber cycle interface circuit (CICS) 41 3, data transformers 415, a microprocessor 417 and other elements. The TR DD Positive of VF 203 is coupled to the digital subscriber line 204 and is coupled to the lines 217 for the 4-wire SDD signals. The VF Positive DD TR is also coupled to the tip (T) and ring (R) 213 lines. The incoming 160 Kbps 2BIQ signals from the central digital subscriber line 204 to the LSD 401 transformer. The SDL transformer 401 and associated resistive elements (not shown) isolate, condition and equalize the impedance to the 2B1Q signal in a unidirectional binary signal at 256 kbps for transmission through the line 423 to the CCI 405. The unidirectional binary signal includes user data and control data The CCEI 403 uses 512 kbps and 8 kbps clocks of the integrated circuit of the client 407 via line 430 to control the time of the signal conversions. The 512 kbps and 8 kbps clocks are synchronized from the 160 Kbps 1BIQ signal on the 204 digital subscriber line. The CCI 405 converts the 256 kbps bit signal from the CCEI 403 in the middle of a stream of "alternating" characters bidirectionally for use in the customer's integrated 407 circuit via line 427. The customer's integrated circuit 407 in the VF 203 DD Positive DD operates in a similar manner as the VF 201 Positive DD TOC. The customer's integrated circuit 407, provides aspects of time control and data management. In one embodiment, the customer's integrated circuit 407 is a Programmable Compound Layout in 3000 Series Xílinx, however, other integrated circuit devices may also be used.

In the TR DD Positive of VF 203, the integrated circuit phase of the client 407 closes its internal clocks to the incoming 160 kbps 2B 1 Q signal and provides selected clock frequencies. For example, the customer's integrated circuit 407 provides a secondary speed transmission clock (Clk) for the 4-wire SDD signal to the SDD-B 41 1 via line 439. The customer's integrated circuit 407 also provides signals to 64 kbps, 512 kbps, and 1 5,360 Mbps for its own use and for the CCI 405, the CCEI 403, and other circuits. The customer's integrated circuit 407 relies on a dual CFC arrangement to provide its time control aspects. In addition to the time control aspects, the integrated circuit of the client 407 transmits or receives the bidirectional "alternating" signal of 512 kbps to and from CCI 405. The 8-character words contained therein are demultiplexed into four binary TTL signals 64 kbps, representing the 4-wire SDD signal, the analog signal, the C and I signal, and the monitor signal. The user data signal representing the analog signal enters the CODEC filter 4099 via the lines 433. The CODEC filter 409 receives on the clock signal (Clk) of 64 kbps from the integrated circuit of the client 407 via the line 437 to convert the binary TTL signal to an analog signal. The analog signal from the CODEC filter 409 enters SIIC 413 via lines 441. The SLIC conditions the analog telephone signal to be used in a telephone and the like.

The 64 kbps user data signal representing the 4-wire SDD signal enters SDD-B 411 via lines 435. The SDD-B 411 receives the clock signal (Clk) from the customer's integrated circuit 407 via line 439 and use the clock signal to convert the binary TTL data to the 4-wire SDD signal. The integrated circuit of the client 407 generates a secondary speed clock signal used by the SDD-B 411 to control the time of the data output through the data of the transformer 415. The 4-wire SDD signal from SDD-B 411 enters the data transformer via lines 443. The data transformer and associated resistive elements (not shown) isolate, conditional and equalize the impedance of the 4-wire SDD signal to USD / USC 219 via lines 449. USD / USC 219 converts 4-wire SDD signals into signals such as RS-232C, V.35, or similar compatible for use as the 221 dte.

The outgoing signals are processed through the VF 203 DD DD Positive in a similar but inverse method like the incoming signals. The 4-wire SDD signal originates from the USD / USC 219 and enters the data transformer 415 via the lines 451. The data transformer 415 and associated resistive elements (not shown) isolate, equalize the impedance and condition the SDD signal of 4 wires for SDD-B 411 via the lines 445. SDD-B 411 converts the 4-wire SDD signal from the data transformer 415 into a binary TTL signal for transmission to the customer's integrated circuit 407 via lines 435.

The analogue outgoing signal from a telephone enters via lines 213 and enters SLIC 413. SLIC conditions the analog signal for CODEC filter 409 and transmits the signal to lines 441. CODEC filter 409 converts the analog SLIC signal in a digital signal. The digital signal enters the customer's integrated circuit 407 via lines 433 and clock (Clk) 437. The client's integrated circuit 407 receives clock control signals from line 429 and converts the digital signals from the CODEC filter 409 and the SDD-B 411 in two 64 kbps signals which define two user data signals. The C and I signal and the monitor signal each at 64 kbps are multiplexed on the two user data signals to provide the "alternating" bidirectional character stream of 512 kbps from the customer's integrated circuit 407 to the CCI 405 via line 427. The CCI 405 converts the user data selected control data at 512 kbps into two unidirectional 256 kbps binary signals representing the incoming and outgoing signals. The 256 kbps signal that leaves the CCI 405 enters the CCEI 403 via line 425. The CCEI 403 converts the 256 kbps binary signal from CCI 405 into the CCEI 403 via line 425. The CCEI 403 converts the binary signal of 256 kbps in a quaternary signal in the 2B1Q format at a transmission speed of 160 kbps. The 2B1Q formatted outgoing signal of the CCEI 403 enters the LSD transformer 401 via the line 421. The LSD 401 transformer and associated resistive elements (not shown) isolate, equalize the impedance and condition the outgoing 2BIQ formatted signal for transmission over the digital subscriber line 204 which is a single twisted pair telephone line. The monitor data, ring data, and other data which is recorded by the microprocessor 417 is made available to the microprocessor 417 via lines 431 and 453. Without limiting the scope of the invention in any way, Table 1 provides a list of commercially available components which are useful in the operation of the TR DD Positive of VF 203 and TOC DD Positive of VF 201 according to the previous modality. The components listed in Table 1 are representative of those that can be used in association with the present invention and are provided for the purpose of facilitating the assembly of an apparatus according to the invention. A variety of known components could be easily replaced or functionally combined or even separated. Integrated circuits based on CMOS have been used where possible in a way that reduces the power consumption of the TR in particular.

Table 1: Components of TR DD Positive of VF The system described above includes bypass circuits to change the multiplexed digital use of the single twisted pair to the STAC transmission if the simplex energy is lost, that is, the energy is passed from Positive DD TOC of VF 201 to TR DD positive of VF over twisted pair. Figure 5 is a block diagram of derivation circuits 500 according to the invention. The block diagram includes circuit elements of normal mode 501 of TOC DD Positive of VF and circuit elements of normal mode 503 of TR DD Positive of VF. The circuit elements of normal mode are similar to the elements in the TOC DD Positive of VF 201 and the TR DD Positive of VF 203 described above. During normal operation, the bypass circuits allow the incoming analog telephone signal on line 205 to operate with the circuit elements of normal mode of TOC DD Positive VF 201 via lines 515, 519 the TR DD Positive of VF 203 via lines 523, 527. A simplex power loss in bypass circuit 508 of TOC DD Positive of VF derives the incoming analog telephone signal from line 205 around the normal mode of elements of the TOC circuit DD Positive of VF 501 to the outgoing twisted pair telephone line 204. The voltage V + in a voltage sensor 514 goes to zero and the voltage sensor 514 sends control signals via lines 533 and 535 to the switches 504 and 505, respectively, to bypass the incoming analog telephone signals to the lines 517. The switches 504, 505, isolate the analogue telephone signal derived from the circuit elements of normal mode 501. The circuit of TR DD Positive ivation of VF 506 operates in a similar manner. Since the VF 203 Positive DD TR receives its twisted pair power 204 during normal mode operation, a power failure in the Positive DD TOC of VF 201 also results in power failure in the TR DD Positive of FV 203 During the power failure, the incoming analog telephone signal from the twisted pair telephone line 204 derives the elements of the normal mode circuit 503 to a 21 1 telephone. The voltage V + in the voltage sensor 51 1 goes to zero during the lack of power and the control signals via the lines 537 and 539 enter the switches 507 and 509, respectively. The switches 507, 509, derive the incoming analog telephone signal from the twisted pair 204 via the lines 525 to the telephone 21 1. The switches 507, 509 also isolate the circuit elements 503 in a normal way from the analogue derived telephone signals. The bypass circuits 508, 506 of TR D D Positive of VF and the Positive DD TOC of VF, allow the user to rely on STAC during a power failure. Alternatively, an inability to sustain a condition connected between the circuit VT 503 of TR DD Positive of VF in normal mode and the circuit 501 of TOC DD of VF in normal mode, results in the redirecting circuits in the analog telephone signal in VF. a similar way. Branch circuits can be used to derive the analog telephone signal for other reasons. The present invention can be used to transmit one or more voice channels and one or more data channels on a twisted pair as shown in Figure 2a. The digital signal that is transmitted from the location of the telephone company to the subscriber's property can be at character speeds such as 288 kbps, 416 kbps, 784 kbps and 168 kbps. Integrated circuits are available to do this using the H LSD transition technology. In analogy with the embodiment described above, one or more voice channels may be converted to the first binary signals and one or more 4-wire data signals may be converted to second binary signals. All of these first and second binary signals can be multiplexed into a higher speed binary signal. This higher speed binary signal can be converted to a digital signal using, v.gr. , the transmission code from 2 B 1 Q to 144 ksymbol / s, 158 ksymbol / s, 392 kymbol / s, 84 kymbol / s, etc. In the remote terminal this digital signal is converted to a higher speed binary signal. This higher speed binary signal is then separated into first and second binary signals. The first binary signals are converted into analog voice channels for transmission over twisted pairs to the subscriber's equipment. The second binary signals are converted to 4-wire digital data circuits for transmission to the subscriber's equipment.

Claims (18)

1. CLAIMS 1. A method for converting an analog voice channel signal and a 4 wire digital signal into a single signal which can be transferred over a single twisted pair line, the method comprising the steps of: a. converting the analog voice channel signal into a first binary signal; b. converting the 4-wire digital signal into a second binary signal; c. combining the first binary signal and the second binary signal in a higher-level binary signal; and d. convert the higher-level binary signal into a 2-wire digital signal. The method according to claim 1, wherein the 4-wire digital signal is a bipolar signal of a digital data service channel (SDD). The method according to claim 1 or claim 2, wherein the 4-wire digital signal is a video signal, a data signal or a speech signal. The method according to any of claims 1 to 3, wherein the 4-wire digital signal has a signaling rate of 2.4 kbps, 4.8 kbps, 9.6 kbps, 56 kbps or 64 kbps. 5. The method according to any of claims 1 to 4, wherein the analog voice channel signal is a voice signal. The method according to any one of claims 1 to 5, wherein the higher speed binary signal has a bit rate of 256 kbps and the digital signal of 2 to lam bres has a bit rate of 160 kbps. The method according to any of claims 1 to 6, wherein the 2 wire digital signal has a 2B 1 Q format or a 4B3T format. 8. A method for transferring an analog voice channel signal and a 4 wire digital signal from a first location to a second location on a single twisted pair line between the locations, the method comprising e. in one of the locations, converting an analog voice signal and a 4 wire digital signal into a 2 wire digital signal by the method of the first aspect of the invention; F. transfer the 2-wire digital signal from step (e) onto the single line of the twisted pair to the other location; and g. in the other location, i. convert the 2-wire digital signal from step (f) to a higher-level binary signal, ii. separating a first binary signal and a second binary signal from a higher-level binary signal produced in step (g (i)), and iii. converting the first binary signal obtained in step (g (ü)) into an analog voice channel signal and converting the second binary signal obtained in step (g (ü)) into a 4-wire digital signal. The method according to claim 8, wherein the single twisted pair has a length of at least 5,486 meters and comprises wires of different calibers. The method according to claim 8 or claim 9, wherein the higher speed binary signal obtained in step (g (i)) is the same as the higher speed binary signal in step (c), the first and second binary signals obtained in step (g (ii)) are the same as the first and second binary signals in steps (a) and (b), the analog voice channel signal obtained in step g (iii) ) is the same as the analog signal in step (a) and the 4-wire digital signal obtained in step (g (ív)) is the same as the digital signal of 4 wires in step (b). The method according to claim 10d, wherein said 2-wire digital signals are transferred from the first location to the second location and from the second location to the first location. 12. The apparatus suitable for use in the method according to any of claims 1 to 7, the apparatus comprising: 1. means for receiving a voice signal of analog channel; 2. means for receiving a 4-wire digital signal; 3. means for converting the analog voice channel signal into a first binary signal; 4. means for converting the digital signal of 4 wires into a second binary signal; Means for combining the first binary signal and the second binary signal in a higher-level binary signal; 6. means for converting the higher-level binary signal into a 2-wire digital format; and 7. means for transferring the 2-wire digital signal to a single twisted pair line. The apparatus suitable for use in the other location in the method according to any of claims 8 to 10, the apparatus comprising: 1. means for receiving a 2-wire digital signal; 2. means for converting the 2-wire digital signal into a higher-level binary signal; 3. means for separating a first binary signal and a second binary signal from the higher-level binary signal; 4. means for converting the first binary signal into an analog voice channel signal; and 5. means for converting the second binary signal into a 4-wing digital signal. 14. The apparatus suitable for use in each of the first and second locations in the method according to claim 10, the apparatus comprising: I. means for receiving an analog voice channel signal; 2. means for receiving a 4-wire digital signal; 3. means for converting the analog voice channel signal into a first binary signal; 4. means for converting the digital signal of 4 wires into a second binary signal; Means for combining the first binary signal and the second binary signal in a higher speed binary signal; 6. means for converting the upper speed binary signal into a 2 wire digital format; 7. means to receive a 2-wire digital signal; 8. means for converting the digital signal of 2 wires into a higher speed binary signal; 9. means for separating a first binary signal and a second binary signal from the higher speed binary signal; 10. means for converting the first binary signal into an analog voice channel signal; and I I. means for converting the second binary signal into a 4-wing digital signal. 15. The apparatus according to any of claims 12 to 14, which comprises means for transferring the analog signal directly to the twisted pair line. 16. A method for converting one or more analog voice channels and one or more 4-wire digital signals into a single signal that can be transferred on a single twisted pair line, the method comprising the steps of: aa. converting each analog voice channel signal into a first binary signal; ab. Convert each digital signal of 4 wires into a second binary signal; ac. Combine the first binary signals and the second binary signals in a higher speed binary signal; and ad. Convert the higher speed binary signal into a 2 wire digital signal. 17. A method for transferring one or more analog voice channel signals and one or more 4 wire digital signals from a first location to a second location on a single twisted pair line between the locations, the method comprising: ae. in one of the locations, converting an analog voice channel signal and a 4 wire digital signal into a 2 wire digital signal by the method of the first aspect of the invention according to claim 16; af transfer the 2-wire digital signal from step (ae) onto the single line of the twisted pair to the other location; and ag. in the other location, i. convert the 2-wire digital signal from step (af) to a higher-level binary signal, ii. separating a first binary signal and a second binary signal from a higher-level binary signal produced in step (ag (i)), and iii. converting the first binary signal obtained in step (ag (ii)) into an analog voice channel signal and converting the second binary signal obtained in step (ag (i)) into a 4-wire digital signal. 18. The method according to claim 1 to 6, or claim 17, wherein the 2-wire digital signal has a bit rate of 288 kbps, 416 kbps, 784 kbps or 1 168 kbps. R ESUMEN A method and apparatus (200) for converting a analog voice signal signal to a 4-wire digital signal into a single 2-wire signal that can be transferred on a single line in twisted pair (205) . In one aspect, the method comprises the steps of converting the analog speech channel signal into a first binary signal, converting the digital 4-wire signal into a second binary signal, combining the first binary signal and the second binary signal into a signal higher speed binary and converting the higher speed binary signal into a 2 wire digital signal that can be transmitted to another location on a single twisted pair line. In another aspect, the method comprises the steps of converting a digital signal of 2 wires to a higher speed binary signal., separating a first binary signal and a second binary signal from a higher speed binary signal and converting the first binary signal into an analog voice channel signal and converting a second binary signal into a digital 4 wire signal. The apparatus (200) includes a positive digital remote voice data terminal (203) easily installed and a positive digital voice data central office terminal (201). The apparatus can provide a gain of 3 to 1 pairs by multiplexing signals representing analog voice telephone signals and 4-wire digital data signals.