WO1996025816A1 - Identification du demandeur et mise en instance des appels pour ela multiples sur une seule ligne telephonique - Google Patents

Identification du demandeur et mise en instance des appels pour ela multiples sur une seule ligne telephonique Download PDF

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Publication number
WO1996025816A1
WO1996025816A1 PCT/US1996/001115 US9601115W WO9625816A1 WO 1996025816 A1 WO1996025816 A1 WO 1996025816A1 US 9601115 W US9601115 W US 9601115W WO 9625816 A1 WO9625816 A1 WO 9625816A1
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WO
WIPO (PCT)
Prior art keywords
signal
telephone line
lead
coupled
ccpe
Prior art date
Application number
PCT/US1996/001115
Other languages
English (en)
Inventor
Harry W. Lewis
Ron Anglikowski
Original Assignee
Cidco, Incorporated
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from US08/388,108 external-priority patent/US5583924A/en
Priority claimed from US08/431,172 external-priority patent/US5745557A/en
Application filed by Cidco, Incorporated filed Critical Cidco, Incorporated
Priority to JP8524967A priority Critical patent/JPH11500282A/ja
Priority to EP96903717A priority patent/EP0809907A1/fr
Publication of WO1996025816A1 publication Critical patent/WO1996025816A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/57—Arrangements for indicating or recording the number of the calling subscriber at the called subscriber's set
    • H04M1/573—Line monitoring circuits for detecting caller identification
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/71—Substation extension arrangements
    • H04M1/715—Substation extension arrangements using two or more extensions per line
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/42—Systems providing special services or facilities to subscribers
    • H04M3/428—Arrangements for placing incoming calls on hold

Definitions

  • This invention is related to telephone subscriber systems and more particularly to systems having caller identification and call waiting for multiple CPEs on a single telephone line.
  • the call waiting (“CW) feature available on many telephone operating systems allows the telephone operating system to notify a user currently
  • the system notifies the user of the third party's call by using a special CW tone.
  • the subscriber has the option to put the second party on hold to receive the third party's call or ignore the CW tone.
  • CPE customer premises
  • the user's CPE has circuitry to receive and decode the digital signal and display the caller's telephone number. This allows the user to answer or ignore the call based on the caller's telephone number.
  • Some CPEs allow for using the CID and CW features together in a CIDCW system, whereby the user's
  • CIDCW systems do not allow for simultaneously using multiple conventional CIDCW CPEs on the same telephone line for at least the following reasons: the circuitry of the conventional CIDCW CPEs tests for other CPEs being off-hook and shuts off the CIDCW capability in such cases; the user(s) would hear the CID information being transmitted from the central office (the CID information signal is typically irritating for the user(s) to hear); any voice signals from the user(s) would interfere with the handshaking signals used in transmitting the CID information; and the conventional CIDCW CPEs would cause contention problems when each CIDCW CPE attempts to transmit an acknowledgement signal in response to a signal from the operating system indicating a third party is trying to call.
  • a system allowing a plurality of CPEs on a single telephone line to display a third party's caller information while users are communicating with a second party.
  • the CPEs in accordance with the present invention are hereinafter referred to as CCPEs for conforming CPEs.
  • one CCPE of the plurality of CCPEs is a primary CCPE, whereas the remaining CCPE(s) are secondary CCPE(s).
  • each CCPE detects whether a CPE alerting signal ("CAS") tone has been transmitted by the central office, thereby detecting when the third party is calling.
  • CAS CPE alerting signal
  • the primary CCPE After all of the CCPEs are on-hook, the primary CCPE then goes off-hook and transmits a CAS
  • CAS ACK CAS acknowledgement
  • the CCPEs then reconnect the telephone line to the house telephone of the CCPE and then the primary CCPE goes on-hook.
  • contention during the CAS ACK signal transmission is avoided and each CCPE of the plurality of CCPEs coupled to the single telephone line displays the caller information, even if the users are communicating with the second party on secondary CCPEs.
  • NCPEs convevtional CPEs without CIDCW circuitry according to the present invention
  • CCPEs convevtional CPEs without CIDCW circuitry according to the present invention
  • Each CCPE detects whether a CAS tone has been sent by the central office. Upon detection of a CAS tone, each CCPE disconnects the CCPE's telephone from the telephone line and goes on- hook. Each CCPE then detects if any NCPE is off-hook.
  • the primary CCPE When no off-hook NCPE is detected, the primary CCPE goes off-hook and transmits the CAS ACK signal to the central office and waits for central office to respond with the CID information. The secondary CCPEs remain on-hook and wait for the caller information. The central office responds to the CAS ACK signal by transmitting the CID information, which the CCPEs then display. Each CCPE then reconnects the CCPE's
  • each CCPE of the plurality of CCPEs coupled to the single telephone line displays the CID information, even if the users are communicating with the second party on secondary CCPEs.
  • each CCPE also includes (i) a signal generator capable of outputting a carrier signal having a frequency meeting government
  • each CCPE coupled to the telephone line monitors the telephone line for the carrier signal. If the CCPE does not detect the carrier signal, then the CCPE enters a primary CCPE mode in which the CCPE transmits the carrier signal over the telephone line and operates as a primary CCPE as described above for the previous embodiment.
  • the first CCPE to be connected to the telephone line is typically the primary CCPE.
  • the primary CCPE then periodically transmits the carrier signal over the telephone line.
  • the CCPE enters a secondary CCPE mode and operates as a secondary CCPE as described above for the previous embodiment. While in the secondary mode, the CCPE continues to monitor the telephone line for the carrier signal to maintain itself in the secondary mode. If the secondary CCPE does not detect the periodic carrier signal, then it will transmit the carrier signal over the telephone to declare itself primary CCPE.
  • a self-arbitrating CIDCW system with multiple CCPEs is provided, which is transparent to the user. Accordingly, the user need not preconfigure the CCPEs when initially coupling a CCPE to the telephone line.
  • this embodiment can be more fault
  • preconfigured primary CCPE fails or is disconnected from the
  • the CIDCW feature will probably not function because no acknowledgement signal is sent to the central office in response to a CAS tone.
  • this embodiment maintains the CIDCW feature because the secondary CCPEs constantly monitor whether the primary CCPE is functioning.
  • the primary CCPE modulates the carrier signal with a predetermined code.
  • the modulation can be either AM or FM.
  • the primary CCPE uses FSK modulation to transmit a security code when transmitting the carrier signal. As a result, this embodiment is more robust and less sensitive to external signals and other noise on the telephone line.
  • FIG. 1 shows a block diagram of a CIDCW system having a plurality of CPEs according to one embodiment of the present invention.
  • FIG. 2 which is comprised of FIGs. 2a and 2b, shows a block diagram of one embodiment of an adjunct depicted in FIG. 1.
  • FIG. 3 which is comprised of FIGS. 3a and 3b, shows a flow diagram illustrating the operation of the CIDCW system depicted in the embodiment of FIG. 1.
  • FIG. 4 shows a timing diagram illustrating signal timing of some of the signals depicted in FIGs. 2 and 3.
  • FIG. 5 which is comprised of FIGs. 5a and 5b, shows a schematic diagram of one embodiment of the power supply depicted in FIG. 2.
  • FIG. 6, which is comprised of FIGs 6a and 6b, shows a schematic diagram of one embodiment of the ring detector, polarity guard, line in use circuit, and phone line switch depicted in FIG. 2.
  • FIG. 7, which is comprised of FIGs. 7a and 7b, shows a schematic diagram of one embodiment of the data reception circuit depicted in FIG. 2.
  • FIG. 8 which is comprised of FIGs. 8a and 8b, shows a schematic diagram of one embodiment of the 4-bit custom controller depicted in FIG. 2.
  • FIG. 9, which is comprised of FIGs. 9a, 9b and 9c, shows a schematic diagram of one embodiment of the LCD depicted in FIG. 2.
  • FIG. 10 which is comprised of FIGs 10a and 10b, shows a schematic diagram of one embodiment of the 8- bit control processor depicted in FIG. 2.
  • FIG. 11 which is comprised of FIGs. 11a and lib, shows a block diagram of a self-arbitrating CCPE according to another embodiment of the present
  • FIG. 12 shows a flow diagram of a self-arbitration process according to one embodiment of the present invention.
  • FIG. 13 shows a schematic diagram of a signal detector according to one embodiment of the present invention.
  • FIG. 14 shows a schematic diagram of a signal generator according to one embodiment of the present invention.
  • FIG. 15 which is comprised of FIGs. 15a and 15b, shows a block diagram of a CCPE according to another embodiment of the present invention.
  • FIG. 1 shows a block diagram of a CIDCW system 100 allowing multiple CPEs on a single telephone line to display a third party's caller information while a user is communicating with a second party.
  • a CCPE 110 is coupled to telephone line 120.
  • Telephone line 120 is the standard two wire telephone line, which includes the ring and tip lines.
  • CCPE 110 comprises a
  • adjunct 112 contains circuitry allowing a user to display a third party's caller information on display 118, including the case where the user is currently communicating with a second party over phone line 120 (i.e., the CIDCW feature).
  • a CCPE 130 comprising a telephone with conforming circuitry and a display 90, is also coupled to
  • CCPE 130 can utilize some
  • a CCPE 140 also comprising an adjunct 92 which includes a display 94 and standard telephone 96, is coupled to telephone line 120.
  • a NCPE 150 comprising a standard telephone, is connected directly to telephone line 120.
  • CCPEs one telephone CCPE, and one NCPE
  • other embodiments have different combinations of adjunct CCPEs, telephone CCPEs, computer CCPEs and NCPEs.
  • CCPEs can have other embodiments, such as computers with modems, facsimile machines, or other equipment for transmitting and/or receiving information over
  • FIG. 2 which is comprised of FIGs. 2a and 2b, shows a block diagram of one embodiment of adjunct 112 for coupling a standard telephone to telephone
  • Adjunct 112 is coupled to the telephone line 120 via connector J1 and to the standard telephone (not shown) via connector J2.
  • Connectors J1 and J2 can be a standard telephone connector such as a RJ-11-4 type connector. Pins 3 and 4 of connector J1 are coupled to the ring and tip lines of the telephone line 120 to receive the ring and tip signals from the central office. Pins 1 and 5 of connector J1 are unused in this embodiment, but can be used for coupling to a second telephone line.
  • circuit 210 comprising varistor VR1 and fuse F1 to protect against overvoltage and overcurrent conditions on the ring and tip lines.
  • a ring detector 220 monitors the ring and tip lines and outputs a -RING signal on line 221 when a ring signal is detected on telephone line 120. Ring detector 220 is described in further detail in
  • a custom controller 230 is coupled to line 221 and, thus, receives the -RING signal when ring
  • Custom controller 230 in response to the -RING signal, sets up to receive the CID information for an on-hook incoming call.
  • custom controller 230 generates a PRI/-SEC signal, which configures adjunct 112 as either a primary or secondary.
  • the PRI/- SEC signal output is programmed by jumper connections on custom controller 230.
  • Other embodiments can have the PRI/-SEC signal programmed by other means, such as being hardwired to a voltage source to configure adjunct 112 as a primary, or to a source of ground potential to configure adjunct 112 as a secondary, or a register, flip flop, or memory, which can be loaded at start up or by a control code input by the user.
  • a data reception circuit 240 is also coupled to the ring and tip lines.
  • Data reception circuit 240 serves as a receiver coupled between telephone line 120 and custom controller 230.
  • Data reception circuit 240 receives the caller information as a coded digital signal from the central office.
  • the central office sends the caller information in a frequency shift keying ("FSK") format.
  • FSK frequency shift keying
  • Data reception circuit 240 decodes the FSK signal and outputs the caller information in digital logic voltage levels on output lead 242 via a signal RxD.
  • Data reception circuit 240 also outputs a -CD signal on output lead 243, which indicates that data reception circuit 240 is detecting the carrier signal for the FSK signal transmitted by the central office.
  • Custom controller 230 coupled to lead 242, receives the CID information. In response to the CID
  • custom controller 230 coupled to a
  • LCD 250 via lines 252, transmits driver signals to LCD 250.
  • the driver signals cause LCD 250 to display the caller information.
  • a key circuit 255 is coupled to custom
  • Key circuit 255 is described further in conjunction with FIG. 8.
  • a line-in-use circuit (“LIU") 260 is coupled to the tip and ring lines through a polarity guard 265 via line 266.
  • Polarity guard 265 protects against a miswiring of the tip and ring lines into telephone line 120 and provides the telephone line voltage to line 266.
  • LIU 260 detects whether a CPE is in use (i.e., off-hook) by monitoring the telephone line voltage as described further below in conjunction with FIG. 6.
  • LIU 260 outputs on a line 268 a -OFF_HOOK signal, which is at a logic 0 level when LIU 260 detects that a telephone is off-hook.
  • the -OFF_HOOK signal is
  • custom controller 230 receives custom controller 230 and a control
  • custom controller 230 and control processor 270 know whenever any CPE is off- hook.
  • Data reception circuit 240 also provides a
  • CAS tone filter 275 serves as a frequency detector for detecting frequencies (the frequencies of a CAS tone, in this embodiment).
  • Data reception circuit 240 and CAS tone filter circuit 275 operate to detect when the central office transmits a CAS tone indicating a calling third party's CID information is available while the user is communicating to a second party over telephone line 120.
  • the CAS tone is a dual tone of 2130Hz and 2750Hz and, accordingly, CAS tone filter circuit 275 outputs a 2130 signal (i.e., a 2130Hz square wave signal) and a 2750 signal (i.e., a 2750Hz square wave signal),
  • Control processor 270 is coupled to CAS tone filter circuit 275 via lines 276 and 277 and to a DTMF generator 280 via lines 282. Control processor 270 receives the 2130 and 2750 signals from CAS tone filter circuit 275 over lines 276 and 277.
  • control processor 270 is coupled to the control lead of a relay Kl via line 278.
  • Relay Kl serves as a switch coupled between telephone line 120 and connector J2.
  • Control processor 270 controls the operation of relay Kl to connect or disconnect the ring and tip lines from connector J2 (i.e., disconnects the house telephone).
  • Control processor 270 also receives the PRI/-SEC signal from custom controller 230 via line 279.
  • Custom controller 230 causes the PRI/-SEC signal to be a logic 1 when adjunct 112 is configured as a primary and a logic 0 when adjunct 112 is configured as a
  • control processor 270 When the 2130 and 2750 signals indicate the presence of the CAS tone, control processor 270
  • CAS_DET transmitted to custom controller 230.
  • the assertion of the CAS_DET signal alerts custom controller 230 that a third party is trying to call while telephone line 120 is already in use.
  • adjunct 112 is a primary (i.e., the PRI/-SEC signal is a logic 1)
  • control processor 270 asserts a -GEN_DTMF signal transmitted to DTMF generator 280.
  • DTMF generator 280 transmits a CAS ACK signal to a line hold and DTMF injection ("line hold") circuit 285 via line 286.
  • the line hold circuit serves as an interface between DTMF generator 280 and telephone line 120.
  • Line hold circuit 285 and a phone line switch 290 operate to place adjunct 112 in the off-hook condition.
  • Phone line switch 290 is coupled to control
  • Control processor 270 can cause adjunct 112 to be in an off-hook condition by sending a -TERMINATE_LINE signal to phone line
  • line hold circuit 285 also transmits a version of the DTMF ACK signal generated by DTMF generator 280 to telephone line 120.
  • a power supply 295 directly or indirectly supplies the power and ground potentials to the circuitry of adjunct 112.
  • Power supply 295 includes a battery for back up purposes and can power adjunct 112 to receive on-hook calls.
  • Power supply 295 can be coupled via connector J3 to an AC adapter for converting AC power to a DC voltage to be regulated by power supply 295.
  • Power supply 295 transmits an EPS (for external power source) signal to custom controller 230. Power supply 295 asserts the EPS signal when the output voltage supplied by power supply 295 is above a threshold voltage. If the external power is
  • adjunct 112 can still operate as a CID adjunct.
  • FIG. 2 shows a block diagram of an adjunct
  • FIG. 2 also applies to a block diagram of the pertinent part of a telephone CCPE.
  • FIG. 3 shows a flow diagram illustrating the operation of adjunct 112.
  • Source code executed by control processor 270 to implement the flow diagram of FIG. 3 is contained within the APPENDIX 1
  • a step 300 is the starting point for operation of adjunct 112.
  • the -OFF_HOOK signal from LIU 260 is checked to determine if LIU 260 detected an off-hook condition. If LIU 260 did not detect an off-hook condition, then control processor 270 deasserts the CAS_DET signal in a
  • step 304 and the process returns to step 300.
  • step 306 the CAS_DET signal is checked to determine if the central office sent a CAS tone. If CAS tone is not detected, then the process returns to step 300. On the other hand, if a CAS tone is detected, a 20ms delay timeout is started in a step 308 to allow for different CAS tone detection times for the CCPEs on telephone line 120. In a next step 309, the 20ms timeout is tested to see if it is expired. If the time-out is not complete, the - OFF_HOOK signal is checked in a step 310 to see if a telephone is still off-hook. If the off-hook condition still exists, then the process returns to step 309.
  • step 312 a 65ms relay timeout is started, and the control processor 270 asserts the -RELAY_OUT signal to control relay Kl to disconnect the ring and tip lines from the house phone 114 coupled to adjunct 112.
  • the house phone can no longer couple a
  • Control processor also deasserts the -
  • TERMINATE_LINE signal to cause phone line switch 290 to not couple telephone line 120 to an internal return (DGND) of line hold circuit 285.
  • adjunct 112 also does not cause an off-hook condition.
  • the CCPE of which adjunct 112 is a part of is on- hook.
  • all other CCPEs (if any) coupled to telephone line 120 should also enter the on-hook condition in a similar manner and within the 65ms relay timeout. Accordingly, only NCPEs (if any) currently in use would remain in the off-hook condition.
  • the 20ms timeout procedure (steps 308-310) synchronizes the time when all of the CCPEs go on-hook. As a result, this procedure minimizes the time that telephone line 120 is in the on-hook condition, thereby greatly reducing the risk that the connection to the central office will be broken or that interference will be caused to the DTMF acknowledgement circuitry in the central office.
  • a next step 314 the -OFF_HOOK signal is again checked to determine if a telephone is in the off-hook condition. If an off-hook condition is detected, then the 65ms timeout is checked to see if it expired in a step 315. If the 65ms timeout is not expired, then the process returns to step 314. If the 65ms timeout has expired, then control processor 270 deasserts the
  • Step 316 aborts the CIDCW feature to protect the user on the NCPE telephone(s) from being forced to hear the FSK signal transmitted by the central office.
  • a detection timer is loaded with a time 5ms less than the current value of the 65ms relay timeout in a step 318.
  • a next step 320 if the detection time is 5ms or more, then the detection timer is loaded with 5ms in a step 322 and then the process goes to a next step 324. If the detection time is less than 5ms, then the process goes directly to step 324.
  • step 324 the detection timer starts to count down.
  • a next step 326 checks to see if the detection timer has expired. Steps 318 through 326 provide time for the rest of the CCPEs on telephone line 120 to detect the on-hook condition and get in synchronization for the next step. Thus, the last CPE to enter the on-hook condition in step 312 resynchronizes all of the CCPEs on telephone line 120.
  • control processor 270 checks to see if adjunct 112 is a part of a primary CCPE. If
  • adjunct 112 is a part of a primary CCPE, then in a step 332, control processor 270 loads a timer for 30ms and asserts the -TERMINATE_LINE signal (i.e., setting the primary CCPE off-hook) and the CAS_DET signal.
  • the primary CCPE going off-hook maintains the connection with the central office and allows adjunct 112 to communicate with the central office to receive the CID information.
  • Step 334 the timer is checked to see if the 30ms has expired. Step 334 provides time for telephone line 120 voltage to stabilize after the entering the off-hook condition.
  • control processor 270 asserts the GEN_DTMF signal to enable DTMF generator 280.
  • Control processor 270 also loads the timer with 10ms as a timeout for receive the DTMF_ACK signal from DTMF generator 280.
  • control processor 270 checks to see if DTMF generator 280 has asserted the DTMF_ACK signal
  • control processor 270 asserted the GEN_DTMF signal. If the DTMF_ACK signal is asserted, then in a step 342 control processor 270 asserts the DTMF_LATCH signal, which causes DTMF generator 280 to generate the CAS ACK signal. In steps 344 and 346, control processor checks to see if DTMF generator 280 deasserts the DTMF_ACK signal. If the DTMF_ACK signal is deasserted, then in a step 348, control
  • processor 270 deasserts the DTMF_LATCH signal and reloads the timer for 64 ms. Steps 348 and 350 allow DTMF generator 280 to generate the CAS ACK signal for 64 ms. Once the 64ms timeout is expired, in steps 352 and 354, control processor 270 reloads the timer for a 20ms timeout. Thus, the elapsed time from step 332 to the end of step 354 is approximately 114ms. However, if DTMF generator 280 does not assert the DTMF_ACK signal (step 340) and deassert the DTMF signal (step 346) within 10ms, the process moves directly to step 348 to provide a controlled exit.
  • control processor 270 asserts the CAS_DET signal and starts a 114ms timeout. Control processor does not assert the -TERMINATE_LINE signal and, thus, adjunct 112 does not go off-hook.
  • control processor 270 deasserts the
  • control processor 270 checks to see if the -CD signal has been asserted, indicating that the carrier signal for the FSK CID information signal from the central office has been detected. If the carrier is not present, in a next step 373, control processor 20 restarts the 120ms cd valid timer. In a next step 374, control processor checks 270 to see if the data window timer has expired. If the data window timer has not expired, the process returns to step 372.
  • control processor 270 checks to see if the cd valid timer is expired. If the cd valid timer is not expired, the process returns to step 272.
  • control processor 270 checks to see if the carrier is still present. Step 377 is repeated until the carrier is no longer present to allow the entire FSK CID information to be received, even if the cd valid timer is expired.
  • step 380 control processor 270
  • step 381 deasserts the -RELAY_OUT signal to connect the house telephone and start a 20ms timeout to allow the voltage to the house phone to stabilize.
  • a next step 381 then checks to see if the 20ms timeout has expired. After the 20ms timeout has expired, in a step 382, control processor 270 then deasserts the -TERMINATE_LINE signal and the CAS_DET signal. Then the process returns to step 300 to monitor for the next off-hook condition.
  • FIG. 4 shows an exemplary timing diagram for illustrating part of the CIDCW operation.
  • Control processor 270 monitors telephone line 120 for an off-hook condition (step 302).
  • a user begins using a CPE to communicate with a second party, causing the -OFF_HOOK signal to go low, which control processor 270 detects (step 302).
  • the central office transmits a CAS tone to telephone line 120.
  • Each CCPE on the telephone line detects the CAS tone (step 306) and at about time T170, each CCPE goes on-hook (step 308).
  • control processor 270 asserts the -RELAY_OUT signal, to disconnect the CCPE's house telephone from telephone line 120 (step 312).
  • the -OFF_HOOK signal is deasserted, which in this example occurs at approximately the same time that control processor 270 asserts the -RELAY_OUT signal.
  • control processor 270 in all of the CCPEs on telephone line 120 then asserts the CAS_DET signal (steps 332 and 360).
  • the primary CCPE also asserts the -TERMINATE_LINE signal, thereby causing the primary CCPE to go off-hook
  • step 332 LIU 260 (in all of the CCPEs on telephone line 120) detects the off-hook condition on telephone line 120 and asserts the -OFF_HOOK signal.
  • Control processor 270 in the secondary CCPEs also performs a 114ms timeout (step 360). However, control processor 270 in the primary CCPE asserts the -GEN_DTMF signal received by DTMF generator 280 after a 30ms timeout at about time T210 (steps 334 and 336). Almost immediately thereafter, DTMF generator 280 responds by asserting the DTMF_ACK signal. Control processor 270 then responds almost immediately thereafter by
  • control processor 270 deasserts the -GEN_DTMF signal to end transmission of the CAS ACK signal and starts a 20ms timeout (step 352).
  • Control processor 270 then monitors the - CD signal to detect when the central office is
  • step 372 transmitting the carrier signal for the CID information (step 372). If no carrier is detected, the 120ms cd valid timer is reset. In this example, data reception circuit 240 asserts the -CD signal at approximately time T330.
  • the central office begins transmitting the CID information on telephone line 120 at about time T345, which is received by custom controller 230 via data reception circuit 240.
  • Control processor monitors the -CD signal and the 120ms cd valid timer while receiving the CID information (steps 372 and 376).
  • the CID information is normally completely received before the 120ms cd valid timer has expired and, thus, the central office stops transmitting the carrier signal.
  • data reception circuit 240 deasserts the - CD signal, which in this example, occurs at
  • Control processor detects when the -CD signal is deasserted (step 377) and in response, deasserts the -RELAY_OUT signal to reconnect the CCPE's house telephone and starts a 20ms timeout (step 380).
  • the 20ms timeout expires at about time T465, the primary CCPE deasserts the -
  • the user(s) end the call and telephone line 120 enters the on-hook condition.
  • FIG. 5 which is comprised of FIGs. 5a and 5b, shows a schematic diagram of one embodiment of power supply 295 (FIG. 2).
  • Connector J3 is used to couple power supply 295 to an AC adapter (not shown).
  • the AC adapter is coupled to an AC power source and supplies a DC output of approximately 12 volts to pin 3 of
  • Regulator U2 can be a regulator such as a LM2936 available from National Semiconductor Corporation or a S-81250 regulator available from Seiko-Epson. The data sheet for the LM2936 regulator is herein incorporated by reference. Regulator U2 is coupled to capacitors C3, C4, C18 and C33, diodes D3, D6 and D7, and
  • resistors R9 and R15 to provide a substantially
  • Regulator U3 is configured to supply a voltage VCCA, which is substantially equal to 8 volts. Voltage VCCA is supplied to the analog circuitry of adjunct 112.
  • regulator U2 The input lead of regulator U2 is also coupled to an input lead of a regulator U1.
  • regulator U1 also receives the DC output from the AC adaptor via diode D3.
  • Regulator U1 is a LM78L05ACZ regulator.
  • Regulator U1 is coupled to diode D3 and capacitors C1, C2, C15 and C16 in accordance with the data sheet for the LM78L05ACZ, which is herein incorporated by
  • Regulator U1 outputs on an output lead a voltage VDDX, substantially equal to 5 volts.
  • the output lead of regulator U1 is coupled to control processor 270 and CAS tone filter circuit 275 (FIG. 2), thereby supplying voltage VDDX to control processor 270 and CAS tone filter circuit 275.
  • Detector U5 is also coupled to the output lead of regulator U1.
  • Detector U5 is a MC34064P-5 detector.
  • Resistor R11 is coupled to detector U5 according to the data sheet for the MC34064P-5, which is herein
  • Resistor R11 serves as a pullup resistor on the output line of detector U5.
  • Detector U5 monitors voltage VDDX and asserts the EPS signal when voltage VDDX drops below approximately 4.6 volts.
  • Pin 3 of connector J3 is also coupled to an input lead of a regulator U3 through a diode D2.
  • Regulator U3 is also a LM2936 or S-81250 regulator and is coupled to diode D2 and capacitors C5 , C6, C17 and C19 in accordance with the data sheet for the LM2936
  • Regulator U3 supplies a substantially constant voltage VDD.
  • Voltage VDD is substantially equal to 5 volts and is supplied to the CID circuitry of adjunct 112.
  • voltage VDD is impressed on the emitter of a PNP transistor Q12.
  • Transistor Q12 serves as a pass transistor to output a voltage VX and is controlled by a -ENA signal transmitted by custom controller 230 (FIG. 2).
  • Voltage VX is supplied to data reception circuit 240.
  • a schottky diode D19 has an anode coupled to the collector of transistor Q12, and a cathode coupled to a cathode of a diode D20.
  • Diode D20 has an anode coupled to the output lead of regulator U2. Consequently, Voltage VX and voltage VCCA from regulator U2 are impressed on the anodes of diodes D19 and D20
  • voltage VCCA When external power is adequate, voltage VCCA is approximately 8 volts, which is then output as voltage VXX by diode D20. The cathodes of diodes D19 and D20 are coupled together, outputting voltage VXX on an output lead 501. Thus, if voltage VCCA drops below approximately 5.6 volts, diode D19 becomes conductive and approximately 5 volts (i.e., voltage VX) is output on output lead 501. Voltage VXX is also supplied to data reception circuit 240 (FIG. 2).
  • FIG. 6, which is comprised of FIGs. 6a and 6b, shows a schematic diagram of one embodiment of ring detector 220, polarity guard 265, LIU 260, phone line switch 290 and line hold circuit 285 (FIG. 2).
  • Ring detector 220 is a conventional ring detector circuit that generates the -RING signal via an optical isolator U6.
  • Optical isolator U6 provides isolation between the CPE and telephone line 120.
  • Polarity guard 265 has a first input lead coupled to the tip line and a second input lead coupled to the ring line.
  • Polarity guard 265 is a conventional full wave bridge circuit, which outputs a positive voltage (i.e., the voltage across telephone line 120) on a line 603 even when the ring and tip lines are reversed due to miswiring.
  • LIU 260 has a resistors R19, R64 and R21 connected in series with line 603.
  • the equivalent resistance of resistors R19, R64 and R21 is approximately equal to 30M ⁇ , which meets the isolation requirements of most telephone operating systems.
  • Resistors R19, R64, R21, R22 and R24 form a voltage divider so that when the voltage on line 603 is above approximately 18 volts, the voltage at node 605 is above 8 volts.
  • Diode D22 has an anode connected to node 605 and a cathode connected to the VCCA source (i.e., 8 volts). As a result, diode D22 conducts. Because diode D22 is coupled between the base and emitter of a darlington pair 606 formed by PNP transistors Q7 and Q8,
  • darlington pair 606 is shut off.
  • the output of lead of darlington pair 606 is coupled to the base of
  • darlington pair 606 is off, no base current flows in transistor Q10, thereby turning off transistor Q10.
  • the collector of transistor Q10 is coupled to a
  • Node 607 is coupled output lead 609 and to the VDDX voltage source through a resistor R27.
  • resistor R27 pulls up the voltage at node 607 (and thus, output lead 609).
  • the -OFF_HOOK signal is at a logic 1 level indicating an on-hook condition.
  • diode D22 does not conduct and the base-emitter junctions in darlington pair 606 are forward biased.
  • darlington pair 606 conducts current to the base of transistor Q10, which causes transistor Q10 to conduct.
  • Resistor R23 couples the base and emitter of transistor Q10 to provide a path for leakage current.
  • a diode D23 is coupled between node 607 and a node 611 (between resistors R22 and R24), with the anode of diode D23 coupled to node 611.
  • Diode D23 helps in causing the voltage at node 607 to rise and fall more quickly when telephone line 120 transitions from the on-hook condition to the off-hook condition and vice versa to create hysteresis to reduce chattering on the -OFF_HOOK signal.
  • LIU 260 detects whether the voltage of line 266 (i.e., the telephone line voltage) is above a threshold voltage.
  • LIU 260 serves as a
  • comparator coupled to the telephone line and a
  • the threshold voltage is approximately 18 volts because the voltage of telephone line 120 is at the telephone line battery voltage (typically 48 volts for normal telephone systems or 24 volts for subscriber line concentrator systems) when all the CPEs on
  • telephone line 120 are on-hook, whereas the telephone line voltage is between 2 to 12 volts when a CPE is off-hook.
  • a 18 volt voltage threshold provides good noise margin for detecting when a CPE is off-hook.
  • Line hold circuit 285 receives the DTMF_OUT signal from DTMF generator 280 (FIG. 2) at an input lead 620.
  • the DTMF_OUT signal is the CAS ACK signal to be
  • NPN transistors Q3 and Q11, capacitors C34 and C36, and resistors R63, R28, R12, R31, R29, R30, R32, R35 and R36 form both a coupling circuit used in coupling the DTMF_OUT signal to telephone line 120 and a hold circuit for maintaining the connection with the central office.
  • resistor R12 is trimmed to adjust the output signal generated at the tip and ring lines to meet the amplitude requirements set by the telephone operating system.
  • resistors R35 and R32 are coupled in series between output lead 622 and a ground source. As a result, resistors R35 and R32 in parallel with the rest of line hold circuit 260 form a load of approximately 600 ⁇ to emulate the AC impedance of a telephone.
  • Resistors R31, R29, R30 and R36 bias transistors Q3 and Q11 to conduct a substantially constant current I1. Current I1, together with the current conducted through resistors R35 and R32, meet the holding current requirements of the telephone operating system.
  • phone line switch 290 couples output lead 622 of line hold circuit 285 to telephone line 120 (via polarity guard 265), the central office "sees" an off-hook CPE and does not disconnect the call while the CAS ACK signal is being transmitted to the central office.
  • Phone line switch 290 receives the -TERMINATE_LINE at an input lead 630.
  • a resistor R26 couples input terminal 630 to the base of a PNP transistor Q9.
  • the emitter of transistor Q9 is coupled to the VDDX source, whereas the collector of transistor Q9 is coupled to the base of a NPN transistor Q4.
  • transistor Q9 conducts a base current to transistor Q4 , thereby causing transistor Q4 to conduct. Any leakage current of transistor Q4 or Q9 is conducted away by a resistor R17 between the base and emitter of transistor Q4.
  • FIG. 7 which is comprised of FIGs. 7a and 7b, shows a schematic diagram of one embodiment of data reception circuit 240 (FIG. 2).
  • circuit 240 generates the TONE_OUT signal by filtering and amplifying signals on the tip and ring lines to pass a frequency band containing the CAS tone.
  • Data reception circuit 240 is coupled to the tip and ring lines via capacitors C11 and C12. Capacitors C11 and C12 provide the isolation from telephone line 120 required by the telephone operating system.
  • capacitors C11 and C12 and resistor R61 form a high pass filter.
  • This high pass filter is cascaded with a low pass filter formed by capacitors C50, C51 and C49 and resistors R59 and R60, thereby passing primarily the frequency band containing the CAS tone and CID information transmitted from the central office.
  • the low pass filter is cascaded with an amplifier U7A through resistors R57 and R58, thereby amplifying any signals within the band.
  • Amplifier U7A can be a LM358 amplifier, the data sheet of which is herein incorporated by reference.
  • Capacitors C44 and C46 together with resistors R49 and R50 coupled between the VXX voltage source and the analog ground source serve to provide a substantially noise-free bias point for amplifier U7A.
  • Diodes D15-D17 clamp the input signals to amplifier U7A for protection.
  • Amplifier U7A is cascaded with a high pass filter 710 formed by another LM358 amplifier U7B and capacitors C47, C48, and C45, and resistors R51-R54.
  • the output signal generated by high pass filter 710 is the TONE_OUT signal transmitted to CAS tone filter circuit 275.
  • High pass filter 710 is cascaded to a low pass filter 720 and a phase locked loop (“PLL") device U8.
  • Low pass filter 720 is formed by capacitors C42 and C43, resistors R45, R47 and R48, and a NPN transistor Q13 connected as an emitter follower.
  • PLL device U8 can be a XR2211 PLL, which is configured with
  • PLL device U8 asserts the -CD signal transmitted to custom controller 230 and control processor 270 when PLL device U8 detects the carrier signal. PLL device U8 also outputs the CID information to custom controller 230 via the RxD signal.
  • Custom controller 230 FIG. 8, which is comprised of FIGs. 8a and 8b, shows a schematic diagram of one embodiment of custom controller 230 (FIG. 2).
  • Custom controller 230 receives the RxD and -CD signals from data reception circuit 240 as described above.
  • Custom controller 230 also receives the CAS_DET signal from control
  • processor 270 the -RING signal from ring detector 220, the -OFF_HOOK signal from LIU 260 and the EPS signal from power supply 295.
  • custom controller 230 In response to an assertion of the EPS signal, custom controller 230, after a short delay, stops asserting a RESET signal to initiate a controlled reset of control processor 270 (e.g., during power up).
  • Custom controller 230 comprises a 4-bit controller U4, such as a 624C microcontroller available from S-MOS Systems, Inc. Part of controller U4 is shown in
  • Controller U4 has OSC1 and OSC2 input leads coupled to crystal X1, resistor R13 and capacitor C28 to receive a 32.768KHZ clock signal in accordance with the data sheet for the SMOS 624C microcontroller, which is herein incorporated by reference. Controller U4 also has OSC3 and OSC4 input leads coupled to crystal X2, resistor R14 and capacitors C30 and C31 to receive a 1.0MHZ clock signal.
  • Controller U4 is coupled to key circuit 255 via lines 257.
  • the user asserts the DELETE, PREV and NEXT signals by actuating pushbutton switches 801-803, respectively.
  • controller U4 can access a SRAM U9 coupled to controller U4.
  • Controller U4 can also respond to the DELETE, PREV and NEXT signals to configure adjunct 112 as either a primary or secondary CCPE, configure memory options that allow for storing 30, 60, 85, 99 or 100 calls, and the language options that allow display of messages in different combinations of Spanish, French, or English languages.
  • the memory and language modes can be set by appropriate connections of jumpers A-G, and the H jumper can be used to configure adjunct 112 as either a primary or secondary CCPE.
  • Controller U4 asserts a LED.ON signal to indicate when a message is stored in SRAM U9.
  • Source code executed by controller U4 for configuring adjunct 112 as a primary or secondary CCPE is contained within the
  • a LED circuit 810 is coupled to receive the LED.ON signal, and conducts current through diode LED1 when the LED.ON signal is asserted.
  • Custom controller 230 is programmed to respond to the RxD and -CD signals from data reception
  • processor 270 the -RING signal from ring detector 220, the -OFF_HOOK signal from LIU 260 as described in conjunction with FIGs. 2-4.
  • FIG. 9, which is comprised of FIGs. 9a, 9b and 9c, shows a schematic diagram of the part of controller U4 coupled to LCD 250.
  • Controller U4 is coupled to lines 252 which carry the segment and common drive signals to LCD 250.
  • Capacitors C20-C26 are coupled to controller U4 to boost the voltage of the drive signals that controller U4 generates on lines 252. In the conventional manner, controller U4 drives the
  • FIG. 10 which is comprised of FIGs. 10a and 10b, shows a schematic diagram of one embodiment of control processor 270 and DTMF generator 280 (FIG. 2).
  • the circuitry shown in FIG. 10 is mounted on a daughter board, whereas the circuitry shown in FIGs. 4-9 are mounted on a mother board.
  • the daughter board is connected to the mother board via connectors P4-P6.
  • Control processor 270 comprises a processor U2' and a clock generator 1000.
  • Control processor can be an 8-bit microprocessor such as a 87C51FA, the data sheet of which is herein incorporated by reference.
  • Clock generator 1000 is a conventional clock generator circuit comprising cascaded inverting amplifiers U3A', U3F' and U3E' with a oscillating subcircuit 1020.
  • the output lead 1001 of inverting amplifier U3A' is coupled to the input lead 1002 of inverting
  • Crystal oscillator subcircuit 1020 includes a crystal Y1.
  • First and second leads 1021 and 1022 of crystal Y1 are coupled to a digital ground source through capacitor C22' and C23', respectively.
  • First lead 1021 is coupled to the output lead 1001 through a resistor R36' and the input lead 1002 through resistor R36' and a resistor R37'.
  • Second lead 1022 is coupled to input lead 1002.
  • the output lead of inverting amplifier U3F' is coupled to the input lead of
  • Clock generator 1000 generates a 3.5795MHz clock signal for operating processor U2' and DTMF generator 280.
  • Processor U2' is coupled to receive the PRI/-SEC signal from custom controller 230, the -OFF_HOOK signal from LIU 260, the -CD signal from data reception circuit 240, and the 2130 and 2750 signals from CAS tone filter circuit 275.
  • the CAS tone detection circuitry (which includes data reception circuit 240, control processor 270, and CAS tone filter circuit 275) is disclosed in copending and commonly assigned
  • Processor U2' is programmed to output the
  • Processor U2' is also programmed to generate the handshake signals -GEN_DTMF and DTMF_LATCH transmitted to DTMF generator 280.
  • DTMF generator 280 includes a tone generator U4', such as DTMF tone generator UMC
  • Tone generator U4' is configured to generate a DTMF "D" tone, in accordance with the data sheet for the UMC 91531/A, which is herein incorporated by reference.
  • DTMF generator 280 responds to the assertion of the -GEN_DTMF signal by asserting the DTMF_ACK signal transmitted back to processor U2', which indicates that tone generator U4' is ready to generate the DTMF_OUT (i.e., CAS ACK) signal.
  • Processor U2' responds to the assertion of the DTMF_ACK signal by asserting the
  • Tone generator then generates the DTMF "D" tone as the
  • FIG. 11 which is comprised of FIGs. 11a and lib, shows a block diagram of a self-arbitrating CCPE 1100 according to another embodiment of the present
  • CCPE 1100 is similar in both structure and operation to CCPE 200 (FIG. 2), except that CCPE 1100 includes signal detector 1110 and signal generator 1120 for self-arbitrating whether CCPE 1120 is a primary or secondary CCPE.
  • CCPE 1100 is different from CCPE 200 (FIG. 2) in that CCPE 200 is preconfigured into either a primary or secondary CCPE.
  • the primary CCPE transmits a carrier signal over telephone line 120 declaring itself the primary CCPE to other CCPEs coupled to telephone line 120.
  • the primary CCPE then acknowledges any received CAS tone as described hereinabove for CCPE 200 (FIG. 2) so that the central office can transmit CIDCW information to the subscriber.
  • the carrier signal has a frequency higher than frequencies used for voice and modem communications while meeting the FCC regulations for telephone line signals.
  • the frequency of the carrier signal is 455KHz (a typical intermediate frequency used in many consumer radios), but of course, other frequencies can be used.
  • signal detector 1110 is coupled to the tip and ring lines of telephone line 120 and detects whether a 455KHZ carrier signal is being transmitted over telephone line 120.
  • detector 1110 transmits a signal -IF_DET to custom controller 230 via line 1112.
  • Signal detector 1110 only asserts the -IF_DET signal when a 455KHZ signal is detected.
  • custom controller 230 deasserts the PRI/-SEC signal transmitted on line 279 to control processor 270, thereby causing CCPE 1100 to enter the secondary mode.
  • Custom controller 230 also deasserts a CONTL signal transmitted to signal generator 1120 via a line 1122, thereby turning off signal generator 1120.
  • signal detector 1110 does not detect a 455KHZ signal on telephone line 120, then signal detector 1110 does not assert the -IF_DET signal.
  • custom controller 230 asserts the PRI/-SEC and CNTL signals, thereby causing CCPE 1100 to enter the primary mode and periodically turning on signal generator 1120, respectively.
  • Signal generator 1120 when on, generates a carrier signal having a frequency substantially equal to 455KHZ. Consequently, when CCPE 1100 is in the primary mode, signal generator 1120 periodically transmits a carrier signal burst over telephone line 120 via a line 1124, line hold circuit 285, phone line switch 290 and polarity guard 265. Because
  • CCPE 1100 continues to periodically (e.g., every 10 seconds) transmit the 455KHz signal burst over
  • the 455 KHz signal is detected by other CCPEs (if any) coupled to telephone line 120.
  • CCPEs if any coupled to telephone line 120.
  • These other CCPEs are substantially similar in
  • custom controller 230 continues to monitor line 1112 for assertion of the -IF_DET signal while CCPE 1100 is a secondary CCPE.
  • custom controller 230 asserts the PRI/-SEC signal to cause CCPE 1100 to become a primary CCPE.
  • control processor 270 causes signal generator 1120 to transmit a 455KHZ signal burst over telephone line 120 to declare CCPE 1100 as primary CCPE. This feature allows a CCPE to take over as primary CCPE when the previous primary CCPE is disconnected from the telephone line or no longer functions. This change in primary CCPE is transparent to the subscriber and provides
  • FIG. 12 shows a flow diagram of a self-arbitration process performed by CCPE 1100 (FIG. 11) to become a primary or secondary CCPE.
  • a PRI bit is cleared and all timers are cleared.
  • the PRI bit is set when the CCPE is a primary CCPE and cleared when the CCPE is a secondary CCPE.
  • the self-arbitration process starts with a step 1201.
  • custom controller 270 checks the PRI bit. If the PRI bit is set, then the CCPE is a primary CCPE. In the primary mode, custom controller 270 then performs a step 1203 to reset timer A. Then in a next step 1205, custom controller 270 causes signal generator 1120 to transmit a 455KHZ signal over telephone line 120. Then in a next step 1207, custom controller 270 determines whether timer A has expired. If timer A is not
  • custom controller 270 keeps signal
  • signal generator 1120 on; however, if timer A is expired, then in a step 1209, custom controller 270 turns off signal generator 1120. Thus, signal generator 1120 provides a 455KHZ signal burst having a duration set by timer A.
  • custom controller 270 In a next step 1211, custom controller 270 resets timer A. Custom controller 270, in a step 1213, then determines whether a 455KHZ signal has been detected on telephone line 120 by checking whether signal
  • detector 1110 has asserted the -IF_DET signal. If a 455KHz signal has been detected, then custom
  • controller 270 performs a step 1215 to clear the PRI bit and then returns to step 1201. However, if in step 1213 custom controller 270 does not detect a 455KHz signal, then in a next step 1217, custom controller 270 determines whether timer A has expired. If timer A has not expired, the process returns to step 1213. However, if timer A has expired, then the process returns to step 1201. Steps 1213-1217 help prevent having more than one primary CCPE coupled to the telephone line.
  • the CCPE is a secondary CCPE.
  • custom controller performs a step 1219 to reset timer B.
  • Timer B when reset, is set to a random time which is greater than the time for timer A.
  • custom controller 270 when reset, is set to a random time which is greater than the time for timer A.
  • detector 1110 has asserted the -IF_DET signal. If a 455KHZ signal has been detected, then custom
  • controller 270 returns to step 1201.
  • custom controller 270 determines whether timer B has expired. If timer B has not expired, then custom controller 270 returns to step 1221. However, if timer B has expired, then custom controller 270 performs a step 1225 to set the PRI bit before returning to step 1201.
  • FIG. 13 shows a block diagram of a signal
  • a filter circuit 1310 is coupled to telephone line 130 and operates to pass signals in a frequency band of approximately 455KHZ ⁇ 10KHz to a PLL device 1320, such as a model XR2211, available from Exar Corporation, San Jose, California.
  • PLL device 1320 such as a model XR2211, available from Exar Corporation, San Jose, California.
  • device 1320 asserts the -IF_DET signal transmitted to custom controller 230 via line 1112 when a 455KHz signal is detected on telephone line 130 and,
  • signal detector 1110 is similar to the implementation of data reception circuit 240 shown in FIG. 7, except that different valued resistors and capacitors are used to tune the filters to a 455KHZ center frequency.
  • the -IF_DET signal is generated instead of the -CD signal and the RxD signal is not used.
  • FIG. 14 shows a block diagram of a signal
  • a PLL device 1410 such as model XR215 available from Exar Corporation, is used in this embodiment to generate a carrier signal having a frequency substantially equal to 455KHZ.
  • PLL phase locked loop
  • device 1410 receives the CONTL signal from custom controller 230 and generates a 455KHz signal on line 1124 via a filter circuit 1420.
  • Filter circuit 1420 receives the CONTL signal from custom controller 230 and generates a 455KHz signal on line 1124 via a filter circuit 1420.
  • circuit 1420 is a band pass filter with a pass band equal to approximately 455KHZ ⁇ 10KHz.
  • FIG. 15, which is comprised of FIGs. 15a and 15b, shows a block diagram of a CCPE 1500 according to a second embodiment of the present invention.
  • CCPE 1500 is substantially the same as CCPE 1100 (FIG. 11), except that CCPE has: (i) a signal detector 1510 instead of signal detector 1110 (FIG. 11) to detect a modulated carrier signal when in the secondary mode; and (ii) a signal generator 1520 instead of signal generator 1120 (FIG. 11) to transmit a modulated carrier signal when in the primary mode.
  • CCPE 1500 uses FSK modulation to modulate the carrier in specified security code.
  • CCPE 1500 uses FSK modulation to modulate the carrier in specified security code.
  • CCPE 1500 periodically transmits a predetermined series of FSK modulated bits when in the primary mode.
  • Secondary CCPEs coupled to CCPE 1500 monitor the telephone line for this series of bits to remain in secondary mode.
  • Signal detector 1510 is similar to signal
  • detector 1510 generates MOD_BIT signals corresponding to FSK modulated bits detected on the telephone line.
  • signal detector 1510 the implementation of signal detector 1110 is similar to the implementation of data reception circuit 240
  • Signal generator 1520 is similar to signal
  • Custom controller 230 receives a MOD signal from custom controller 230 in addition to the CONTL signal.
  • Custom controller 230 generates MOD signals
  • signal generator 1520 generates the carrier signal modulated with the security code.
  • controllers processors, PLLs, and tone generators described herein. Also, different devices may be used to present the CID information to the user(s),

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Telephonic Communication Services (AREA)

Abstract

L'invention décrit un système permettant à une pluralité d'équipements locaux d'abonné ('ELA') conformes sur une seule ligne téléphonique d'afficher des informations demandeur relatives à une troisième personne pendant qu'un usager est en communication avec une deuxième personne. Par un procédé d'auto-arbitrage, un ELA conforme sur une pluralité de tels ELA est un ELA conforme primaire, les autres étant des ELA conformes secondaires. Pendant qu'un usager est en communication avec une deuxième personne à l'aide d'un ou de plusieurs des ELA conformes, chacun d'eux détecte si une tonalité de sonnerie d'appel d'ELA ('CPE alerting signal' ou 'CAS') a été transmise par le central téléphonique, détectant ainsi quand une troisième personne appelle. Chaque ELA conforme répond en déconnectant le téléphone de l'ELA conforme de la ligne téléphonique. Après que tous les ELA conformes sont raccrochés, l'ELA conforme primaire décroche et transmet un signal d'accusé de réception CAS ('CAS ACK') au central. Tous les ELA conformes attendent alors que le central téléphonique transmette les informations relatives à l'identification du demandeur en réponse au signal CAS ACK. Pour mettre en oeuvre le procédé d'auto-arbitrage, chaque ELA conforme comporte un détecteur de signal pour détecter un signal ayant une fréquence hors de la bande vocale. Si l'ELA conforme détecte ce signal, il entre alors en mode secondaire. Par contre, s'il ne le détecte pas, il entre alors en mode primaire.
PCT/US1996/001115 1995-02-13 1996-02-12 Identification du demandeur et mise en instance des appels pour ela multiples sur une seule ligne telephonique WO1996025816A1 (fr)

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JP8524967A JPH11500282A (ja) 1995-02-13 1996-02-12 一つの電話回線上の複数のｃｐｅに対する発呼者ｉｄ及び呼出待機
EP96903717A EP0809907A1 (fr) 1995-02-13 1996-02-12 Identification du demandeur et mise en instance des appels pour ela multiples sur une seule ligne telephonique

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US08/388,108 US5583924A (en) 1995-02-13 1995-02-13 Caller ID and call waiting for multiple CPES on a single telephone line
US431,172 1995-04-28
US08/431,172 US5745557A (en) 1995-04-28 1995-04-28 CIDCW primary/secondary arbitration
US388,108 1995-04-28

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997011550A1 (fr) * 1995-09-21 1997-03-27 Northern Telecom Limited Coordination de telephones ou de complements sur la meme ligne
WO1998015096A1 (fr) * 1996-09-30 1998-04-09 Northern Telecom Limited Appareil et procede silencieux pour equipement d'abonne
GB2323242A (en) * 1997-02-28 1998-09-16 Inventec Corp Calling line identification and disply for parallel telephones connected to a single telephone line
WO1998044697A1 (fr) * 1997-03-27 1998-10-08 Northern Telecom Limited Procede et dispositif servant a afficher un appel en attente
WO1998044698A1 (fr) * 1997-03-27 1998-10-08 Northern Telecom Limited Detection de signaux d'alerte d'installation d'abonne combine raccroche
WO1999012327A1 (fr) * 1997-09-04 1999-03-11 Conexant Systems, Inc. Signalisation a une premiere partie pour systeme d'appel en attente-identification de numero demandeur (cwcid)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4703499A (en) * 1986-02-21 1987-10-27 Arturo Fossas Distributed privacy oriented telephone extension system
US5093856A (en) * 1990-10-24 1992-03-03 At&T Bell Laboratories Apparatus and method for determining incoming call destination with improved security
GB2258119A (en) * 1991-07-22 1993-01-27 Northern Telecom Ltd Third party caller identification
WO1993011643A1 (fr) * 1991-12-05 1993-06-10 Sierra Semiconductor Corporation Circuit de telephone de commande de l'etat ''decroche'' pendant la reception d'un signal d'identification de l'appelant
US5388150A (en) * 1992-07-28 1995-02-07 Schneyer; Robin Automatic incoming telephone call identification and disposition system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4703499A (en) * 1986-02-21 1987-10-27 Arturo Fossas Distributed privacy oriented telephone extension system
US5093856A (en) * 1990-10-24 1992-03-03 At&T Bell Laboratories Apparatus and method for determining incoming call destination with improved security
GB2258119A (en) * 1991-07-22 1993-01-27 Northern Telecom Ltd Third party caller identification
WO1993011643A1 (fr) * 1991-12-05 1993-06-10 Sierra Semiconductor Corporation Circuit de telephone de commande de l'etat ''decroche'' pendant la reception d'un signal d'identification de l'appelant
US5388150A (en) * 1992-07-28 1995-02-07 Schneyer; Robin Automatic incoming telephone call identification and disposition system

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997011550A1 (fr) * 1995-09-21 1997-03-27 Northern Telecom Limited Coordination de telephones ou de complements sur la meme ligne
US5937058A (en) * 1995-09-21 1999-08-10 Northern Telecom Limited Coordinating telephones or adjuncts on the same loop
WO1998015096A1 (fr) * 1996-09-30 1998-04-09 Northern Telecom Limited Appareil et procede silencieux pour equipement d'abonne
GB2323242A (en) * 1997-02-28 1998-09-16 Inventec Corp Calling line identification and disply for parallel telephones connected to a single telephone line
GB2323242B (en) * 1997-02-28 2000-03-29 Inventec Corp Apparatus for auto-detecting dialing of a parallel communicat ion device
WO1998044697A1 (fr) * 1997-03-27 1998-10-08 Northern Telecom Limited Procede et dispositif servant a afficher un appel en attente
WO1998044698A1 (fr) * 1997-03-27 1998-10-08 Northern Telecom Limited Detection de signaux d'alerte d'installation d'abonne combine raccroche
WO1999012327A1 (fr) * 1997-09-04 1999-03-11 Conexant Systems, Inc. Signalisation a une premiere partie pour systeme d'appel en attente-identification de numero demandeur (cwcid)
US6404863B1 (en) 1997-09-04 2002-06-11 Conexant Systems, Inc. First party signalling for call waiting calling number identification (CWCID) system

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EP0809907A1 (fr) 1997-12-03

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