CA2303553A1 - A system and method for mitigating intermittent interruptions in an audio radio broadcast system - Google Patents
A system and method for mitigating intermittent interruptions in an audio radio broadcast system Download PDFInfo
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- CA2303553A1 CA2303553A1 CA002303553A CA2303553A CA2303553A1 CA 2303553 A1 CA2303553 A1 CA 2303553A1 CA 002303553 A CA002303553 A CA 002303553A CA 2303553 A CA2303553 A CA 2303553A CA 2303553 A1 CA2303553 A1 CA 2303553A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
- H04H20/20—Arrangements for broadcast or distribution of identical information via plural systems
- H04H20/22—Arrangements for broadcast of identical information via plural broadcast systems
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/12—Frequency diversity
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H60/00—Arrangements for broadcast applications with a direct linking to broadcast information or broadcast space-time; Broadcast-related systems
- H04H60/09—Arrangements for device control with a direct linkage to broadcast information or to broadcast space-time; Arrangements for control of broadcast-related services
- H04H60/11—Arrangements for counter-measures when a portion of broadcast information is unavailable
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/02—Arrangements for detecting or preventing errors in the information received by diversity reception
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
- H04H20/28—Arrangements for simultaneous broadcast of plural pieces of information
- H04H20/30—Arrangements for simultaneous broadcast of plural pieces of information by a single channel
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H2201/00—Aspects of broadcast communication
- H04H2201/10—Aspects of broadcast communication characterised by the type of broadcast system
- H04H2201/18—Aspects of broadcast communication characterised by the type of broadcast system in band on channel [IBOC]
- H04H2201/183—FM digital or hybrid
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H2201/00—Aspects of broadcast communication
- H04H2201/10—Aspects of broadcast communication characterised by the type of broadcast system
- H04H2201/20—Aspects of broadcast communication characterised by the type of broadcast system digital audio broadcasting [DAB]
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/0001—Arrangements for dividing the transmission path
- H04L5/0003—Two-dimensional division
- H04L5/0005—Time-frequency
Abstract
A system (100) for mitigating intermittent interruptions in an audio radio broadcast system is provided wherein a primary radio signal and a redundant radio signal are transmitted from a transmitter subsystem (120) and received by a receiver subsystem (140). The output (112) of an audio source (110) is coupled to a modulator (160) for modulating a radio frequency signal (162) for coupling to a transmit antenna (172). A second output (114) of audio source (110) is coupled to a delay circuit (116), for adding a predetermined time delay thereto. The delayed audio source signal is coupled to a modulator (164) for modulating a second radio frequency signal (166) that is also coupled to the transmit antenna (172). The receiver subsystem (140) receives both the primary radio signal and the delayed redundant radio signal and couples each to a respective demodulator (180, 182). At least demodulator (180) includes a circuit (181) for determining the degradation in the primary radio signal and provides a quality measurement output signal (186) to a blend control circuit (190). The recovered primary audio signal from demodulator (180) is coupled to a second delay circuit (184), the time delay of second delay circuit (184) being substantially equal to the time delay of delay circuit (116). The audio output from delay circuit (184) and the redundant audio output from demodulator (182) are coupled to a blending subsystem (135), wherein each is combined with a weighting factor and then combined together to form a composite audio signal for coupling to the audio output circuit (150).
Claims (48)
1. A system for mitigating intermittent interruptions in an audio radio broadcast system, comprising:
a source of an audio signal;
transmitter means having a first input coupled to said audio source for modulating at least one first carrier signal with said audio signal to broadcast a primary radio signal;
first delay means having an input coupled to said audio source for adding a first predetermined time delay to said audio signal to form a delayed redundant audio signal at an output thereof, said output being coupled to a second input of said transmitter means for modulating at least one second carrier signal with said delayed redundant radio signal to broadcast a delayed redundant radio signal simultaneously with said primary radio signal;
receiver means for receiving said primary radio signal and said delayed redundant radio signal, said receiver means demodulating said primary radio signal to provide said audio signal to a first output thereof and demodulating said delayed redundant radio signal to provide said delayed redundant audio signal to a second output thereof, said receiver means including means for detecting degradation of said received primary radio signal, said means for degradation detection providing a quality measurement signal to a third output of said receiver means;
second delay means having an input coupled to said first output of said receiver means for adding a second predetermined time delay to said audio signal to form a delayed primary audio signal at an output thereof said second predetermined time delay being substantially equal to said first predetermined time delay;
blending means having a first input coupled to an output of said second delay means and second and third inputs respectively coupled to said second and third outputs of said receiver means for combining a first weighting factor with said delayed primary audio signal and a second weighting factor with said delayed redundant audio signal and combining said weighted delayed primary audio signal with said weighted delayed redundant audio signal to form a composite audio signal, said first weighting factor being smoothly transitioned between a first value and a second value responsive to said quality measurement signal being less than a predetermined threshold value, said second weighting factor being smoothly transitioned between said second value and said first value responsive to said quality measurement signal being less than said predetermined threshold value;
and audio output means coupled to said blending means for converting said composite audio signal to an aural signal.
a source of an audio signal;
transmitter means having a first input coupled to said audio source for modulating at least one first carrier signal with said audio signal to broadcast a primary radio signal;
first delay means having an input coupled to said audio source for adding a first predetermined time delay to said audio signal to form a delayed redundant audio signal at an output thereof, said output being coupled to a second input of said transmitter means for modulating at least one second carrier signal with said delayed redundant radio signal to broadcast a delayed redundant radio signal simultaneously with said primary radio signal;
receiver means for receiving said primary radio signal and said delayed redundant radio signal, said receiver means demodulating said primary radio signal to provide said audio signal to a first output thereof and demodulating said delayed redundant radio signal to provide said delayed redundant audio signal to a second output thereof, said receiver means including means for detecting degradation of said received primary radio signal, said means for degradation detection providing a quality measurement signal to a third output of said receiver means;
second delay means having an input coupled to said first output of said receiver means for adding a second predetermined time delay to said audio signal to form a delayed primary audio signal at an output thereof said second predetermined time delay being substantially equal to said first predetermined time delay;
blending means having a first input coupled to an output of said second delay means and second and third inputs respectively coupled to said second and third outputs of said receiver means for combining a first weighting factor with said delayed primary audio signal and a second weighting factor with said delayed redundant audio signal and combining said weighted delayed primary audio signal with said weighted delayed redundant audio signal to form a composite audio signal, said first weighting factor being smoothly transitioned between a first value and a second value responsive to said quality measurement signal being less than a predetermined threshold value, said second weighting factor being smoothly transitioned between said second value and said first value responsive to said quality measurement signal being less than said predetermined threshold value;
and audio output means coupled to said blending means for converting said composite audio signal to an aural signal.
2. The system as recited in Claim 1 where said first predetermined time delay is equal to or greater than 2.0 seconds.
3. The system as recited in Claim 1 further including digital encoding means having an input coupled to said audio source and an output coupled to said first input of said transmitter means.
4. The system as recited in Claim 3 further including digital decoder means having an input coupled to said output of said second delay means and an output coupled to said first input of said blending means.
5. The system as recited in Claim 4 where said means for detecting degradation of said received primary radio signal, includes means for determining one or more parameters selected from the group consisting of signal-to-noise ratio, bit error rate, signal power level and cyclic redundancy check.
6. The system as recited in Claim 4 where said second carrier is at least one FM stereo multiplex subcarrier within an FM broadcast signal spectrum.
7. The system as recited in Claim 6 where said first carrier is at least one subcarrier spaced at least 53 kilohertz from a center frequency of said FM
broadcast signal spectrum.
broadcast signal spectrum.
8. The system as recited in Claim 6 where said first carrier is at least one SCA
subcarrier of said FM broadcast signal spectrum.
subcarrier of said FM broadcast signal spectrum.
9. The system as recited in Claim 1 where said second carrier is at least one radio frequency signal within an FM broadcast signal spectrum.
10. The system as recited in Claim 9 where said first carrier is at least one SCA subcarrier of said FM broadcast signal spectrum.
11. The system as recited in Claim 1 where said first weighting factor is a function smoothly transitioning between 1.0 and 0.0 responsive to said quality measurement signal being less than said predetermined threshold value, said second weighting factor being a function smoothly transitioning between 0.0 and 1.0 responsive to said quality measurement signal being less than said predetermined threshold value.
12. A method of mitigating intermittent interruptions in an audio radio broadcast. comprising the steps of:
(a) providing an audio signal;
(b) modulating at least one first radio frequency signal with said audio signal for transmitting said audio signal as a first radio signal:
(c) adding a first predetermined time delay to said audio signal to form a delayed redundant audio signal;
(d) modulating at least one second radio frequency signal with said delayed redundant audio signal for transmitting said delayed redundant audio signal as a second radio signal:
(e) receiving said first and second radio signals and recovering said audio signal and said delayed redundant audio signal:
(f) making a quality measurement of at least said received first radio signal:
(g) adding a second predetermined time delay to said recovered audio signal to form a delayed primary audio signal, said second predetermined time delay being substantially equal to said first predetermined time delay:
(h) establishing a first weighting factor, said first weighting factor being equal to 1.0 when said quality measurement is at least as great as a predetermined threshold value and smoothly transitioning to 0.0 over a predetermined time period when said quality measurement is less than said predetermined threshold value;
(i) establishing a second weighting factor, said second weighting factor being equal to 0.0 when said quality measurement is at least as great as said predetermined threshold value and smoothly transitioning to 1.0 over said predetermined time period when said quality measurement is less than said predetermined threshold value;
(j) combining said first weighting factor and said delayed primary audio signal, and combining said second weighting factor and said delayed redundant audio signal;
(k) combining said weighted delayed primary audio signal and said weighted delayed redundant audio signal to form a composite audio signal;
and (l) providing an audio output circuit and coupling said composite audio signal thereto.
(a) providing an audio signal;
(b) modulating at least one first radio frequency signal with said audio signal for transmitting said audio signal as a first radio signal:
(c) adding a first predetermined time delay to said audio signal to form a delayed redundant audio signal;
(d) modulating at least one second radio frequency signal with said delayed redundant audio signal for transmitting said delayed redundant audio signal as a second radio signal:
(e) receiving said first and second radio signals and recovering said audio signal and said delayed redundant audio signal:
(f) making a quality measurement of at least said received first radio signal:
(g) adding a second predetermined time delay to said recovered audio signal to form a delayed primary audio signal, said second predetermined time delay being substantially equal to said first predetermined time delay:
(h) establishing a first weighting factor, said first weighting factor being equal to 1.0 when said quality measurement is at least as great as a predetermined threshold value and smoothly transitioning to 0.0 over a predetermined time period when said quality measurement is less than said predetermined threshold value;
(i) establishing a second weighting factor, said second weighting factor being equal to 0.0 when said quality measurement is at least as great as said predetermined threshold value and smoothly transitioning to 1.0 over said predetermined time period when said quality measurement is less than said predetermined threshold value;
(j) combining said first weighting factor and said delayed primary audio signal, and combining said second weighting factor and said delayed redundant audio signal;
(k) combining said weighted delayed primary audio signal and said weighted delayed redundant audio signal to form a composite audio signal;
and (l) providing an audio output circuit and coupling said composite audio signal thereto.
13. The method as recited in Claim 12 where said step of modulating at least one first radio frequency signal includes the step of digitally encoding said audio signal.
14. The method as recited in Claim 13 where said step of receiving includes the step of decoding said recovered audio signal.
15. The method as recited in Claim 12 where said step of adding a first predetermined time delay includes the step of selecting a time delay within the approximating range of 2.0 - 5.0 seconds.
16. The method as recited in Claim 14 where the step of modulating at least one first radio frequency signal includes the step of modulating at least one carrier spaced within the approximating range of 130 - 199 kilohertz from a center frequency of an FM broadcast signal spectrum with said digitally encoded audio signal.
17. The method as recited in Claim 16 where the step of modulating at least one second radio frequency signal includes the step of modulating at least one radio frequency signal within an FM broadcast signal spectrum with said delayed redundant audio signal.
18. The method as recited in Claim 16 where the step of modulating at least one second radio frequency signal includes the step of modulating at least one SCA
subcarrier of said FM broadcast signal spectrum with said delayed redundant audio signal.
subcarrier of said FM broadcast signal spectrum with said delayed redundant audio signal.
19. The method as recited in Claim 12 where said step of making a quality measurement includes the step of determining one or more parameters selected from the group consisting of signal-to-noise ratio, bit error rate, signal power level and cyclic redundancy check.
20. A method of mitigating intermittent interruptions in an in-band on-channel digital audio broadcast system, wherein each channel includes at least one carrier signal modulated with an analog audio signal and a plurality of subcarriers modulated with a digital representation of the analog audio signal, comprising the steps of:
(a) adding a predetermined first time delay to the analog audio signal prior to modulation of the at least one carrier signal, the analog audio signal being delayed relative to the digital representation of the analog audio signal;
(b) providing a receiver for receiving both said at least one modulated carrier signal and said modulated subcarriers to recover said delayed analog audio signal and said digital representation of the analog audio signal;
(c) detecting a predetermined level of degradation in said digital representation of the analog audio signal;
(d) adding a predetermined second time delay to said digital representation of the analog audio signal and converting said delayed digital representation of the analog audio signal to form a primary audio signal; and (e) substituting said delayed analog audio signal for said primary audio signal when said predetermined level of degradation is detected.
(a) adding a predetermined first time delay to the analog audio signal prior to modulation of the at least one carrier signal, the analog audio signal being delayed relative to the digital representation of the analog audio signal;
(b) providing a receiver for receiving both said at least one modulated carrier signal and said modulated subcarriers to recover said delayed analog audio signal and said digital representation of the analog audio signal;
(c) detecting a predetermined level of degradation in said digital representation of the analog audio signal;
(d) adding a predetermined second time delay to said digital representation of the analog audio signal and converting said delayed digital representation of the analog audio signal to form a primary audio signal; and (e) substituting said delayed analog audio signal for said primary audio signal when said predetermined level of degradation is detected.
21. A method of in-band on-channel broadcasting comprising the steps of:
providing a first signal to be broadcast;
providing a second signal to be broadcast;
delaying one of said first signal and said second signal with respect to the other of said first signal and said second signal;
modulating a first carrier with a first one of said first signal and said second signal;
orthogonal frequency division modulating a plurality of subcarriers with a second one of said first signal and said second signal, said plurality of subcarriers being positioned in upper and lower sidebands with respect to said first carrier;
combining said first carrier and said plurality of subcarriers to produce a composite signal; and transmitting said composite signal.
providing a first signal to be broadcast;
providing a second signal to be broadcast;
delaying one of said first signal and said second signal with respect to the other of said first signal and said second signal;
modulating a first carrier with a first one of said first signal and said second signal;
orthogonal frequency division modulating a plurality of subcarriers with a second one of said first signal and said second signal, said plurality of subcarriers being positioned in upper and lower sidebands with respect to said first carrier;
combining said first carrier and said plurality of subcarriers to produce a composite signal; and transmitting said composite signal.
22. A method of in-band on-channel broadcasting as recited in claim 21, wherein said first signal comprises an analog signal and said second signal comprises a digital signal.
23. A method of in-band on-channel broadcasting as recited in claim 21, wherein said first signal comprises a digital signal and said second signal comprises an analog signal.
24. A method of in-band on-channel broadcasting as recited in claim 21, wherein said first signal and said second signal represent the same audio information.
25. A method of in-band on-channel broadcasting as recited in claim 21, wherein:
said first carrier is frequency modulated;
said upper sideband ranges from about 130 kHz to about 199 kHz from said first carrier; and said lower sideband ranges from about -130 kHz to about -199kHz from said first carrier.
said first carrier is frequency modulated;
said upper sideband ranges from about 130 kHz to about 199 kHz from said first carrier; and said lower sideband ranges from about -130 kHz to about -199kHz from said first carrier.
26. A method of in-band on-channel broadcasting as recited in claim 25, each of said upper and lower sidebands contains 95 of said subcarriers.
27. An in-band on-channel broadcasting transmitter comprising:
means for providing a first signal to be broadcast;
means for providing a second signal to be broadcast;
means for delaying one of said first signal and said second signal with respect to the other of said first signal and said second signal;
means for modulating a first carrier with a first one of said first signal and said second signal;
means for orthogonal frequency division modulating a plurality of subcarriers with a second one of said first signal and said second signal, said plurality of subcarriers being positioned in upper and lower sidebands with respect to said first carrier;
means for combining said first carrier and said plurality of subcarriers to produce a composite signal; and means for transmitting said composite signal.
means for providing a first signal to be broadcast;
means for providing a second signal to be broadcast;
means for delaying one of said first signal and said second signal with respect to the other of said first signal and said second signal;
means for modulating a first carrier with a first one of said first signal and said second signal;
means for orthogonal frequency division modulating a plurality of subcarriers with a second one of said first signal and said second signal, said plurality of subcarriers being positioned in upper and lower sidebands with respect to said first carrier;
means for combining said first carrier and said plurality of subcarriers to produce a composite signal; and means for transmitting said composite signal.
28. An in-band on-channel broadcasting transmitter as recited in claim 27, wherein said first signal comprises an analog signal and said second signal comprises a digital signal.
29. An in-band on-channel broadcasting transmitter as recited in claim 27, wherein said first signal comprises a digital signal and said second signal comprises an analog signal.
30. An in-band on-channel broadcasting transmitter as recited in claim 27, wherein said first signal and said second signal represent the same audio information.
31. An in-band on-channel broadcasting transmitter as recited in claim 27, wherein:
said first carrier is frequency modulated;
said upper sideband ranges from about 130 kHz to about 199 kHz from said first carrier; and said lower sideband ranges from about -130 kHz to about -199kHz from said first carrier.
said first carrier is frequency modulated;
said upper sideband ranges from about 130 kHz to about 199 kHz from said first carrier; and said lower sideband ranges from about -130 kHz to about -199kHz from said first carrier.
32. An in-band on-channel broadcasting transmitter as recited in claim 31, each of said upper and lower sidebands contains 95 of said subcarriers.
33. A method of receiving an in-band on-channel broadcast signal including a first carrier modulated by a first signal, a plurality of subcarriers positioned in upper and lower sidebands with respect to said first carrier to be broadcast and orthogonal frequency division modulated by a second signal, wherein one of said first signal and said second signal is delayed with respect to the other of said first signal and said second signal, said method comprising the steps of:
demodulating said first carrier to produce a first demodulated signal;
demodulating said plurality of subcarriers to produce a second demodulated signal;
delaying one of said first and second demodulated signals with respect to the other of said first and second demodulated signals;
selecting one said first and second demodulated signals to be used to produce an output signal; and producing an output signal in response to the selected one of said first and second demodulated signals.
demodulating said first carrier to produce a first demodulated signal;
demodulating said plurality of subcarriers to produce a second demodulated signal;
delaying one of said first and second demodulated signals with respect to the other of said first and second demodulated signals;
selecting one said first and second demodulated signals to be used to produce an output signal; and producing an output signal in response to the selected one of said first and second demodulated signals.
34. A method of receiving an in-band on-channel broadcast signal as recited in claim 33, wherein said first signal comprises an analog signal and said second signal comprises a digital signal.
35. A method of receiving an in-band on-channel broadcast signal as recited in claim 33, wherein said first signal comprises a digital signal and said second signal comprises an analog signal.
36. A method of receiving an in-band on-channel broadcast signal as recited in claim 33, wherein said first signal and said second signal represent the same audio information.
37. A method of receiving an in-band on-channel broadcast signal as recited in claim 33, wherein:
said first carrier is frequency modulated;
said upper sideband ranges from about 130 kHz to about 199 kHz from said first carrier; and said lower sideband ranges from about -130 kHz to about -199kHz from said first carrier.
said first carrier is frequency modulated;
said upper sideband ranges from about 130 kHz to about 199 kHz from said first carrier; and said lower sideband ranges from about -130 kHz to about -199kHz from said first carrier.
38. A method of receiving an in-band on-channel broadcast signal as recited in claim 37, each of said upper and lower sidebands contains 95 of said subcarriers.
39. A method of receiving an in-band on-channel broadcast signal as recited in claim 33, wherein said step of selecting one said first and second demodulated signals to be used to produce an output signal comprises the step of:
detecting degradation of one said first and second demodulated signals by determining one or more parameters selected from the group consisting of signal-to-noise ratio, bit error rate, signal power level and cyclic redundancy check.
detecting degradation of one said first and second demodulated signals by determining one or more parameters selected from the group consisting of signal-to-noise ratio, bit error rate, signal power level and cyclic redundancy check.
40. A method of receiving an in-band on-channel broadcast signal as recited in claim 33, wherein said step of selecting one said first and second demodulated signals to be used to produce an output signal comprises the step of:
providing a quality measurement signal representative of said first signal;
establishing a first weighting factor when said quality measurement is less than said predetermined threshold value;
establishing a second weighting factor when said quality measurement is less than said predetermined threshold value;
combining said first weighting factor and said first signal, and combining said second weighting factor and said second signal; and combining said weighted first signal and said weighted second signal to form a composite audio signal; and coupling said composite audio signal to an output.
providing a quality measurement signal representative of said first signal;
establishing a first weighting factor when said quality measurement is less than said predetermined threshold value;
establishing a second weighting factor when said quality measurement is less than said predetermined threshold value;
combining said first weighting factor and said first signal, and combining said second weighting factor and said second signal; and combining said weighted first signal and said weighted second signal to form a composite audio signal; and coupling said composite audio signal to an output.
41. A receiver for an in-band on-channel broadcast signal including a first carrier modulated by a first signal, a plurality of subcarriers positioned in upper and lower sidebands with respect to said first carrier to be broadcast and orthogonal frequency division modulated by a second signal, wherein one of said first signal and said second signal is delayed with respect to the other of said first and said second signal, said receiver comprising:
means for demodulating said first carrier to produce a first demodulated signal;
means for demodulating said plurality of subcarriers to produce a second demodulated signal;
means for delaying one of said first and second demodulated signals with respect to the other of said first and second demodulated signals;
means for selecting one said first and second demodulated signals to be used to produce an output signal; and means for producing an output signal in response to the selected one of said first and second demodulated signals.
means for demodulating said first carrier to produce a first demodulated signal;
means for demodulating said plurality of subcarriers to produce a second demodulated signal;
means for delaying one of said first and second demodulated signals with respect to the other of said first and second demodulated signals;
means for selecting one said first and second demodulated signals to be used to produce an output signal; and means for producing an output signal in response to the selected one of said first and second demodulated signals.
42. A receiver for an in-band on-channel broadcast signal as recited in claim 41, wherein said first signal comprises an analog signal and said second signal comprises a digital signal.
43. A receiver for an in-band on-channel broadcast signal as recited in claim 41, wherein said first signal comprises a digital signal and said second signal comprises an analog signal.
44. A receiver for an in-band on-channel broadcast signal as recited in claim 41, wherein said first signal and said second signal represent the same audio information.
45. A receiver for an in-band on-channel broadcast signal as recited in claim 41, wherein:
said first carrier is frequency modulated;
said upper sideband ranges from about 130 kHz to about 199 kHz from said first carrier; and said lower sideband ranges from about -130 kHz to about -199kHz from said first carrier.
said first carrier is frequency modulated;
said upper sideband ranges from about 130 kHz to about 199 kHz from said first carrier; and said lower sideband ranges from about -130 kHz to about -199kHz from said first carrier.
46. A receiver for an in-band on-channel broadcast signal as recited in claim 45, each of said upper and lower sidebands contains 95 of said subcarriers.
47. A receiver for an in-band on-channel broadcast signal as recited in claim 41, wherein said means for selecting one said first and second demodulated signals to be used to produce an output signal comprises:
means for detecting degradation of one said first and second demodulated signals by determining one or more parameters selected from the group consisting of signal-to-noise ratio, bit error rate, signal power level and cyclic redundancy check.
means for detecting degradation of one said first and second demodulated signals by determining one or more parameters selected from the group consisting of signal-to-noise ratio, bit error rate, signal power level and cyclic redundancy check.
48. A receiver for an in-band on-channel broadcast signal as recited in claim 41, wherein said means for selecting one said first and second demodulated signals to be used to produce an output signal comprises:
means for providing a quality measurement signal representative of said first signal;
means for establishing a first weighting factor when said quality measurement is less than said predetermined threshold value;
means for establishing a second weighting factor when said quality measurement is less than said predetermined threshold value;
means for combining said first weighting factor and said first signal, and combining said second weighting factor and said second signal; and means for combining said weighted first signal and said weighted second signal to form a composite audio signal; and means for coupling said composite audio signal to an output.
means for providing a quality measurement signal representative of said first signal;
means for establishing a first weighting factor when said quality measurement is less than said predetermined threshold value;
means for establishing a second weighting factor when said quality measurement is less than said predetermined threshold value;
means for combining said first weighting factor and said first signal, and combining said second weighting factor and said second signal; and means for combining said weighted first signal and said weighted second signal to form a composite audio signal; and means for coupling said composite audio signal to an output.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/947,902 US6178317B1 (en) | 1997-10-09 | 1997-10-09 | System and method for mitigating intermittent interruptions in an audio radio broadcast system |
US08/947,902 | 1997-10-09 | ||
PCT/US1998/021746 WO1999020007A1 (en) | 1997-10-09 | 1998-10-06 | A system and method for mitigating intermittent interruptions in an audio radio broadcast system |
Publications (2)
Publication Number | Publication Date |
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CA2303553A1 true CA2303553A1 (en) | 1999-04-22 |
CA2303553C CA2303553C (en) | 2010-01-05 |
Family
ID=25486969
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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CA002303553A Expired - Lifetime CA2303553C (en) | 1997-10-09 | 1998-10-06 | A system and method for mitigating intermittent interruptions in an audio radio broadcast system |
Country Status (12)
Country | Link |
---|---|
US (2) | US6178317B1 (en) |
EP (1) | EP1025663A1 (en) |
JP (1) | JP3976087B2 (en) |
KR (1) | KR100508577B1 (en) |
CN (1) | CN1185815C (en) |
AU (1) | AU752576B2 (en) |
BR (1) | BRPI9812741B1 (en) |
CA (1) | CA2303553C (en) |
ID (1) | ID24754A (en) |
MX (1) | MXPA00003407A (en) |
RU (1) | RU2213422C2 (en) |
WO (1) | WO1999020007A1 (en) |
Families Citing this family (92)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3073656A1 (en) * | 1997-11-11 | 2016-09-28 | SnapTrack, Inc. | Transmitter and transmitting method, information editor and editing method, receiver and receiving method, information storage and storing method, and broadcasting system |
US6445750B1 (en) * | 1998-04-22 | 2002-09-03 | Lucent Technologies Inc. | Technique for communicating digitally modulated signals over an amplitude-modulation frequency band |
WO1999065149A1 (en) * | 1998-06-09 | 1999-12-16 | Sony Corporation | Receiver and method of reception |
JP2000115116A (en) * | 1998-10-07 | 2000-04-21 | Nippon Columbia Co Ltd | Orthogonal frequency division multiplex signal generator, orthogonal frequency division multiplex signal generation method and communication equipment |
US6259893B1 (en) * | 1998-11-03 | 2001-07-10 | Ibiquity Digital Corporation | Method and apparatus for reduction of FM interference for FM in-band on-channel digital audio broadcasting system |
US6590944B1 (en) * | 1999-02-24 | 2003-07-08 | Ibiquity Digital Corporation | Audio blend method and apparatus for AM and FM in band on channel digital audio broadcasting |
US6430401B1 (en) * | 1999-03-29 | 2002-08-06 | Lucent Technologies Inc. | Technique for effectively communicating multiple digital representations of a signal |
DE19914742A1 (en) * | 1999-03-31 | 2000-10-12 | Siemens Ag | Method of transferring data |
US6154452A (en) * | 1999-05-26 | 2000-11-28 | Xm Satellite Radio Inc. | Method and apparatus for continuous cross-channel interleaving |
US7058086B2 (en) * | 1999-05-26 | 2006-06-06 | Xm Satellite Radio Inc. | Method and apparatus for concatenated convolutional encoding and interleaving |
US7085377B1 (en) * | 1999-07-30 | 2006-08-01 | Lucent Technologies Inc. | Information delivery in a multi-stream digital broadcasting system |
US6721337B1 (en) * | 1999-08-24 | 2004-04-13 | Ibiquity Digital Corporation | Method and apparatus for transmission and reception of compressed audio frames with prioritized messages for digital audio broadcasting |
US7974255B2 (en) * | 1999-09-15 | 2011-07-05 | Alcatel-Lucent Usa Inc. | Method and apparatus for multi-stream transmission with time and frequency diversity in an orthogonal frequency division multiplexing (OFDM) communication system |
US7343015B2 (en) * | 1999-11-16 | 2008-03-11 | Radio Shack Corporation | Method and apparatus for high fidelity wireless stereophonic transmission utilizing dual frequency carriers |
US7092774B1 (en) * | 2000-02-29 | 2006-08-15 | Prime Image, Inc. | Multi-channel audio processing system with real-time program duration alteration |
US6671340B1 (en) * | 2000-06-15 | 2003-12-30 | Ibiquity Digital Corporation | Method and apparatus for reduction of interference in FM in-band on-channel digital audio broadcasting receivers |
US6792051B1 (en) | 2000-07-25 | 2004-09-14 | Thomson Licensing S.A. | In-band-on-channel broadcast system for digital data |
FR2815492B1 (en) * | 2000-10-13 | 2003-02-14 | Thomson Csf | BROADCASTING SYSTEM AND METHOD ENSURING CONTINUITY OF SERVICE |
US7580488B2 (en) * | 2000-11-29 | 2009-08-25 | The Penn State Research Foundation | Broadband modulation/demodulation apparatus and a method thereof |
US7088740B1 (en) * | 2000-12-21 | 2006-08-08 | Bae Systems Information And Electronic Systems Integration Inc | Digital FM radio system |
DE10103400A1 (en) * | 2001-01-26 | 2002-08-14 | Bosch Gmbh Robert | Audio service switching method for a radio receiver |
US7218623B1 (en) * | 2001-05-04 | 2007-05-15 | Ipr Licensing, Inc. | Coded reverse link messages for closed-loop power control of forward link control messages |
DE60115390T2 (en) * | 2001-05-14 | 2006-07-13 | Sony Deutschland Gmbh | Radio receiver with antenna and frequency diversity |
US7106809B2 (en) * | 2001-05-21 | 2006-09-12 | Visteon Global Technologies, Inc. | AM/FM/IBOC receiver architecture |
DE10144907A1 (en) | 2001-09-12 | 2003-04-03 | Infineon Technologies Ag | Transmission arrangement, in particular for mobile radio |
US7221917B2 (en) | 2002-05-01 | 2007-05-22 | Ibiquity Digital Corporation | Adjacent channel interference mitigation for FM digital audio broadcasting receivers |
JP2004004274A (en) * | 2002-05-31 | 2004-01-08 | Matsushita Electric Ind Co Ltd | Voice signal processing switching equipment |
EP1370017A1 (en) * | 2002-06-07 | 2003-12-10 | Sony International (Europe) GmbH | Interference reduction for simulcast signals |
WO2004004178A1 (en) * | 2002-06-28 | 2004-01-08 | Micronas Gmbh | Wireless audio signal transmission method for a three-dimensional sound system |
US7221688B2 (en) | 2002-07-31 | 2007-05-22 | Ibiquity Digital Corporation | Method and apparatus for receiving a digital audio broadcasting signal |
JP2006501724A (en) * | 2002-09-27 | 2006-01-12 | アイビキュイティ・デジタル・コーポレイション | Method and apparatus for interleaving signal bits in a digital audio broadcasting system |
US7551675B2 (en) * | 2002-09-27 | 2009-06-23 | Ibiquity Digital Corporation | Method and apparatus for synchronized transmission and reception of data in a digital audio broadcasting system |
US6898249B2 (en) * | 2002-12-17 | 2005-05-24 | Ibiquity Digital Corporation | Method and apparatus for AM digital audio broadcasting with amplitude scaled tertiary subcarriers |
US7280813B2 (en) * | 2003-03-13 | 2007-10-09 | Peter Fortier Elliott | Variable delay radio receiver |
US7228100B2 (en) * | 2003-03-25 | 2007-06-05 | Visteon Global Technologies, Inc. | Program data display in duplicative digital audio broadcasting system |
JP2004349805A (en) * | 2003-05-20 | 2004-12-09 | Alpine Electronics Inc | Iboc broadcast receiver |
JP4133604B2 (en) * | 2003-06-10 | 2008-08-13 | アルパイン株式会社 | Radio receiver |
JP4053932B2 (en) * | 2003-06-20 | 2008-02-27 | 株式会社ケンウッド | IBOC broadcast receiver. |
DE502004011313D1 (en) * | 2003-09-29 | 2010-08-05 | Siemens Ag | METHOD FOR IMPROVING THE QUALITY OF A LANGUAGE TRANSMISSION THROUGH AN AIR INTERFACE |
US7305056B2 (en) * | 2003-11-18 | 2007-12-04 | Ibiquity Digital Corporation | Coherent tracking for FM in-band on-channel receivers |
JP4236564B2 (en) * | 2003-11-21 | 2009-03-11 | 富士通テン株式会社 | Audio broadcast receiver |
US7546088B2 (en) * | 2004-07-26 | 2009-06-09 | Ibiquity Digital Corporation | Method and apparatus for blending an audio signal in an in-band on-channel radio system |
US7298696B1 (en) * | 2004-10-14 | 2007-11-20 | Wu William W | Blockage mitigation techniques for information transmission |
JP2006115200A (en) * | 2004-10-14 | 2006-04-27 | Fujitsu Ten Ltd | Receiver |
US20060099927A1 (en) * | 2004-11-11 | 2006-05-11 | Nvidia Corporation | Integrated wireless transceiver and audio processor |
KR100599765B1 (en) | 2005-03-18 | 2006-07-12 | 주식회사 문화방송 | Broadcasting audio part report system and control method thereof |
CN1921678A (en) * | 2005-08-24 | 2007-02-28 | 华为技术有限公司 | Different-frequency cell/different system identification and measurement result reporting method |
CA2601063C (en) * | 2005-08-24 | 2015-02-17 | Huawei Technologies Co., Ltd. | Method and user equipment for measurement, determining required measurement performance and selecting serving cell |
US7460847B2 (en) * | 2005-09-01 | 2008-12-02 | Sigmatel, Inc. | Handheld audio system with radio receiver and method for use therewith |
US20070063982A1 (en) * | 2005-09-19 | 2007-03-22 | Tran Bao Q | Integrated rendering of sound and image on a display |
CN101877588B (en) * | 2005-12-06 | 2012-05-30 | 罗姆股份有限公司 | Frequency modulator and fm transmission circuit using the same |
US20070171891A1 (en) * | 2006-01-26 | 2007-07-26 | Available For Licensing | Cellular device with broadcast radio or TV receiver |
US20070222734A1 (en) * | 2006-03-25 | 2007-09-27 | Tran Bao Q | Mobile device capable of receiving music or video content from satellite radio providers |
US7827491B2 (en) * | 2006-05-12 | 2010-11-02 | Tran Bao Q | Systems and methods for video editing |
US8976727B2 (en) * | 2006-10-22 | 2015-03-10 | Viasat, Inc. | Cyclical obstruction communication system |
US8290060B2 (en) * | 2007-08-21 | 2012-10-16 | Limberg Allen Leroy | Staggercasting of DTV signals that employ concatenated convolutional coding |
EP2186338A1 (en) * | 2007-08-28 | 2010-05-19 | Thomson Licensing | Staggercasting with no channel change delay |
US8180470B2 (en) * | 2008-07-31 | 2012-05-15 | Ibiquity Digital Corporation | Systems and methods for fine alignment of analog and digital signal pathways |
US8068563B2 (en) * | 2008-10-20 | 2011-11-29 | Ibiquity Digital Corporation | Systems and methods for frequency offset correction in a digital radio broadcast receiver |
JP4784653B2 (en) * | 2009-01-23 | 2011-10-05 | ソニー株式会社 | Audio data transmitting apparatus, audio data transmitting method, audio data receiving apparatus, and audio data receiving method |
JP2010219649A (en) * | 2009-03-13 | 2010-09-30 | Sanyo Electric Co Ltd | Receiving apparatus |
US20110113301A1 (en) * | 2009-11-06 | 2011-05-12 | Limberg Allen Leroy | Diversity broadcasting of gray-labeled CCC data using 8-VSB AM |
US8724968B2 (en) | 2011-04-07 | 2014-05-13 | Prime Image Delaware, Inc. | Embedded ancillary data processing method and system with program duration alteration |
US8804865B2 (en) | 2011-06-29 | 2014-08-12 | Silicon Laboratories Inc. | Delay adjustment using sample rate converters |
US8976969B2 (en) | 2011-06-29 | 2015-03-10 | Silicon Laboratories Inc. | Delaying analog sourced audio in a radio simulcast |
US20130003637A1 (en) * | 2011-06-29 | 2013-01-03 | Javier Elenes | Dynamic time alignment of audio signals in simulcast radio receivers |
US9113133B2 (en) | 2012-01-31 | 2015-08-18 | Prime Image Delaware, Inc. | Method and system for detecting a vertical cut in a video signal for the purpose of time alteration |
US9252899B2 (en) * | 2012-06-26 | 2016-02-02 | Ibiquity Digital Corporation | Adaptive bandwidth management of IBOC audio signals during blending |
US9094139B2 (en) * | 2012-06-26 | 2015-07-28 | Ibiquity Digital Corporation | Look ahead metrics to improve blending decision |
US8948272B2 (en) | 2012-12-03 | 2015-02-03 | Digital PowerRadio, LLC | Joint source-channel decoding with source sequence augmentation |
US9191256B2 (en) | 2012-12-03 | 2015-11-17 | Digital PowerRadio, LLC | Systems and methods for advanced iterative decoding and channel estimation of concatenated coding systems |
US8595590B1 (en) | 2012-12-03 | 2013-11-26 | Digital PowerRadio, LLC | Systems and methods for encoding and decoding of check-irregular non-systematic IRA codes |
EP2747314A1 (en) | 2012-12-19 | 2014-06-25 | Nxp B.V. | A system for blending signals |
JP5981408B2 (en) * | 2013-10-29 | 2016-08-31 | 株式会社Nttドコモ | Audio signal processing apparatus, audio signal processing method, and audio signal processing program |
US9837061B2 (en) * | 2014-06-23 | 2017-12-05 | Nxp B.V. | System and method for blending multi-channel signals |
KR102289143B1 (en) * | 2014-10-28 | 2021-08-13 | 현대엠엔소프트 주식회사 | Audio blending apparatus of fm bandwidth dab system |
US9596044B2 (en) | 2015-02-13 | 2017-03-14 | Ibiquity Digital Corporation | Method and apparatus for analog and digital audio blend for HD radio receivers |
US9819480B2 (en) | 2015-08-04 | 2017-11-14 | Ibiquity Digital Corporation | System and method for synchronous processing of analog and digital pathways in a digital radio receiver |
US9768948B2 (en) | 2015-09-23 | 2017-09-19 | Ibiquity Digital Corporation | Method and apparatus for time alignment of analog and digital pathways in a digital radio receiver |
US9947332B2 (en) | 2015-12-11 | 2018-04-17 | Ibiquity Digital Corporation | Method and apparatus for automatic audio alignment in a hybrid radio system |
US9755598B2 (en) | 2015-12-18 | 2017-09-05 | Ibiquity Digital Corporation | Method and apparatus for level control in blending an audio signal in an in-band on-channel radio system |
US9768853B1 (en) | 2016-03-16 | 2017-09-19 | Ibiquity Digital Corporation | Method and apparatus for blending an audio signal in an in-band on-channel radio system |
US10666416B2 (en) | 2016-04-14 | 2020-05-26 | Ibiquity Digital Corporation | Time-alignment measurement for hybrid HD radio technology |
US9832007B2 (en) | 2016-04-14 | 2017-11-28 | Ibiquity Digital Corporation | Time-alignment measurement for hybrid HD radio™ technology |
US10419064B2 (en) | 2017-03-31 | 2019-09-17 | Schweitzer Engineering Laboratories, Inc. | One-way broadcast communication |
US10484115B2 (en) | 2018-02-09 | 2019-11-19 | Ibiquity Digital Corporation | Analog and digital audio alignment in the HD radio exciter engine (exgine) |
US10177729B1 (en) | 2018-02-19 | 2019-01-08 | Ibiquity Digital Corporation | Auto level in digital radio systems |
CN110299955B (en) * | 2018-03-21 | 2024-02-13 | 厦门歌乐电子企业有限公司 | Broadcast receiving device and method |
US10912104B2 (en) | 2019-02-01 | 2021-02-02 | Schweitzer Engineering Laboratories, Inc. | Interleaved, static time division multiple access (TDMA) for minimizing power usage in delay-sensitive applications |
US11397198B2 (en) | 2019-08-23 | 2022-07-26 | Schweitzer Engineering Laboratories, Inc. | Wireless current sensor |
US11567109B2 (en) | 2019-10-11 | 2023-01-31 | Schweitzer Engineering Laboratories, Inc. | Capacitor bank control using wireless electrical measurement sensors away from capacitor bank |
WO2021101570A1 (en) * | 2019-11-22 | 2021-05-27 | Lisnr | Magnitude equalization of audio-based data transmissions |
Family Cites Families (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CH474923A (en) | 1967-06-29 | 1969-06-30 | Siemens Ag | Method for unidirectional data transmission via message connections susceptible to failure and reconstruction of the disturbed bits |
NL166591C (en) | 1971-05-18 | 1981-08-17 | Philips Nv | ERROR-CORRECTING DATA TRANSMISSION SYSTEM. |
US3922607A (en) * | 1974-08-14 | 1975-11-25 | Drake Co R L | Radio broadcasting system |
US4291405A (en) * | 1979-09-07 | 1981-09-22 | Bell Telephone Laboratories, Incorporated | Error reduction speech communication system |
US4382299A (en) | 1980-11-07 | 1983-05-03 | Rca Corporation | Disc record system employing signal redundancy |
US4660193A (en) * | 1983-10-11 | 1987-04-21 | Regency Electronics, Inc. | Digital modulation method for standard broadcast FM subcarrier |
US5146612A (en) * | 1989-04-17 | 1992-09-08 | Spingarn James L | Technique for using a subcarrier frequency of a radio station to transmit, receive and display a message together with audio reproduction of the radio program |
US5241538A (en) * | 1990-01-18 | 1993-08-31 | Matsushita Electric Industrial Co., Ltd. | Transmission apparatus |
US5179576A (en) * | 1990-04-12 | 1993-01-12 | Hopkins John W | Digital audio broadcasting system |
US5278826A (en) * | 1991-04-11 | 1994-01-11 | Usa Digital Radio | Method and apparatus for digital audio broadcasting and reception |
US5584051A (en) | 1991-11-01 | 1996-12-10 | Thomson Consumer Electronics Sales Gmbh | Radio broadcast transmission system and receiver for incompatible signal formats, and method therefor |
US5465396A (en) | 1993-01-12 | 1995-11-07 | Usa Digital Radio Partners, L.P. | In-band on-channel digital broadcasting |
JP3074103B2 (en) * | 1993-11-16 | 2000-08-07 | 株式会社東芝 | OFDM synchronous demodulation circuit |
JP3360399B2 (en) | 1994-02-28 | 2002-12-24 | ソニー株式会社 | Digital audio broadcasting receiver |
US5673292A (en) * | 1994-10-07 | 1997-09-30 | Northrop Grumman Corporation | AM-PSK system for broadcasting a composite analog and digital signal using adaptive M-ary PSK modulation |
US5581576A (en) * | 1995-01-12 | 1996-12-03 | International Business Machines Corp. | Radio information broadcasting and receiving system |
US5592471A (en) | 1995-04-21 | 1997-01-07 | Cd Radio Inc. | Mobile radio receivers using time diversity to avoid service outages in multichannel broadcast transmission systems |
EP0744847B1 (en) | 1995-05-23 | 2005-08-24 | Koninklijke Philips Electronics N.V. | Redundant data transmission system using at least two channels |
US5764706A (en) * | 1995-08-31 | 1998-06-09 | Usa Digital Radio Partners, L.P. | AM compatible digital waveform frame timing recovery and frame synchronous power measurement |
JPH09116475A (en) * | 1995-10-23 | 1997-05-02 | Nec Corp | Time diversity transmission/reception system |
JP3338747B2 (en) * | 1995-12-28 | 2002-10-28 | 日本電気株式会社 | Interference wave canceller |
US5867530A (en) * | 1996-06-14 | 1999-02-02 | Trw Inc. | Method and apparatus for accomodating signal blockage in satellite mobile radio systems |
US5949796A (en) * | 1996-06-19 | 1999-09-07 | Kumar; Derek D. | In-band on-channel digital broadcasting method and system |
US6144705A (en) * | 1996-08-22 | 2000-11-07 | Lucent Technologies Inc. | Technique for simultaneous communications of analog frequency-modulated and digitally modulated signals using precanceling scheme |
US6005894A (en) * | 1997-04-04 | 1999-12-21 | Kumar; Derek D. | AM-compatible digital broadcasting method and system |
US5940444A (en) * | 1997-04-18 | 1999-08-17 | Trw Inc. | DARS PSF with no data rate increase |
US5907582A (en) * | 1997-08-11 | 1999-05-25 | Orbital Sciences Corporation | System for turbo-coded satellite digital audio broadcasting |
CA2388905C (en) * | 2001-06-06 | 2010-03-02 | Pennzoil-Quaker State Company | Composition and method for cleaning, protecting and restoring surfaces |
-
1997
- 1997-10-09 US US08/947,902 patent/US6178317B1/en not_active Expired - Lifetime
-
1998
- 1998-10-06 BR BRPI9812741A patent/BRPI9812741B1/en not_active IP Right Cessation
- 1998-10-06 CN CNB988099721A patent/CN1185815C/en not_active Expired - Lifetime
- 1998-10-06 CA CA002303553A patent/CA2303553C/en not_active Expired - Lifetime
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- 1998-10-06 MX MXPA00003407A patent/MXPA00003407A/en active IP Right Grant
- 1998-10-06 JP JP2000516452A patent/JP3976087B2/en not_active Expired - Fee Related
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- 1998-10-06 WO PCT/US1998/021746 patent/WO1999020007A1/en not_active Application Discontinuation
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- 2000-12-22 US US09/747,143 patent/US6901242B2/en not_active Expired - Lifetime
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