Neighborhood node mapping methods and apparatus for ingress mitigation in cable communication systems
원문보기
IPC분류정보
국가/구분
United States(US) Patent
등록
국제특허분류(IPC7판)
H04B-010/00
H04J-014/00
H04B-003/02
H04B-003/50
H04B-003/46
H04J-003/00
H04J-003/16
H04W-052/22
H04L-012/26
H04B-010/2575
H04Q-011/00
H04B-010/114
H04N-017/00
H04N-021/61
출원번호
US-0539383
(2012-06-30)
등록번호
US-8948596
(2015-02-03)
발명자
/ 주소
Nielsen, Steven
Totten, Ronald
Halky, Travis
출원인 / 주소
CetusView Technologies, LLC
인용정보
피인용 횟수 :
2인용 특허 :
32
초록▼
A mobile transmitter traverses a drive path in a neighborhood node of a cable communication system and broadcasts a test signal at frequencies falling within an upstream path bandwidth. A navigational device generates a first record of positions of the transmitter along the drive path, and an analyz
A mobile transmitter traverses a drive path in a neighborhood node of a cable communication system and broadcasts a test signal at frequencies falling within an upstream path bandwidth. A navigational device generates a first record of positions of the transmitter along the drive path, and an analyzer monitors the upstream path bandwidth and generates a second record of received signal amplitudes of the transmitted test signal as a function of time. An ingress map is generated showing the drive path and potential points of ingress in the node, and employed to remediate faults particularly in the hardline coaxial cable plant. Iterative generation of maps and corresponding remediation in the node enable improved cable communication systems with reduced noise profiles between 5 MHz and 20 MHz and employing higher modulation order QAM communication channels (e.g., 256-QAM and higher) throughout the upstream path bandwidth to increase upstream capacity.
대표청구항▼
1. A method for facilitating detection of ingress in at least one neighborhood node of a cable communication system, the cable communication system comprising: a headend or hub comprising:a headend optical/radio frequency (RF) converter; anda cable modem system coupled to the headend optical/RF conv
1. A method for facilitating detection of ingress in at least one neighborhood node of a cable communication system, the cable communication system comprising: a headend or hub comprising:a headend optical/radio frequency (RF) converter; anda cable modem system coupled to the headend optical/RF converter; anda first neighborhood node of the at least one neighborhood node, the first neighborhood node having an infrastructure comprising:a first fiber optic cable coupled to the headend optical/RF converter;a first node optical/RF converter coupled to the first fiber optic cable;a first RF hardline coaxial cable plant, coupled to the first node optical/RF converter and traversing the first neighborhood node, to convey to the headend or hub at least first upstream information from a plurality of first subscriber premises over an upstream path bandwidth including a range of frequencies from approximately 5 MHz to at least approximately 42 MHz; anda plurality of first subscriber service drops, coupled to the first RF hardline coaxial cable plant and to the plurality of first subscriber premises, to provide the first upstream information from the plurality of first subscriber premises to the first RF hardline coaxial cable plant,the method comprising:A) directing a mobile broadcast apparatus including a transmitter along a first neighborhood node drive path proximate to the first RF hardline coaxial cable plant so as to effectively traverse and ensure substantially full coverage of the first subscriber neighborhood;B) during A), broadcasting from the transmitter a test signal at a plurality of locations distributed along at least a substantial portion of the first neighborhood node drive path, the test signal having at least one test signal frequency falling within the upstream path bandwidth;C) during A), electronically recording first geographic information corresponding to respective positions of the mobile broadcast apparatus along at least the substantial portion of the first neighborhood node drive path so as to generate a first record of the first geographic information;D) during A) and throughout traversing at least the substantial portion of the first neighborhood node drive path, recording, via an analyzer coupled to a first junction of the cable modem system and the headend optical/RF converter or a second junction of the hardline cable plant and the first node optical/RF converter, a plurality of signal amplitudes at the test signal frequency so as to generate a second record, the plurality of signal amplitudes representing a strength of a received upstream test signal as a function of time, based on B) and test signal ingress of the test signal into at least one fault in the first RF hardline coaxial cable plant; andE) based on the first record generated in C) and the second record generated in D), electronically generating a first neighborhood node ingress map comprising:a first graphical representation of the first neighborhood node drive path; anda second graphical representation, overlaid on the first graphical representation, of the plurality of signal amplitudes, at least along the substantial portion of the first neighborhood node drive path, so as to illustrate the test signal ingress of the test signal into at least the first RF hardline coaxial cable plant of the first neighborhood node. 2. The method of claim 1, wherein: B) comprises broadcasting from the transmitter the test signal at the plurality of locations distributed along an entirety of the first neighborhood node drive path;C) comprises electronically recording the first geographic information corresponding to the respective positions of the mobile broadcast apparatus along the entirety of the first neighborhood node drive path so as to generate the first record of the first geographic information;D) comprises recording the plurality of signal amplitudes at the test signal frequency throughout traversing the entirety of the first neighborhood node drive path so as to generate the second record; andin E), the second graphical representation is based on the plurality of signal amplitudes recorded along the entirety of the first neighborhood node drive path, so as to illustrate the test signal ingress of the test signal into at least the first RF hardline coaxial cable plant of the first neighborhood node. 3. The method of claim 1, wherein in B), the test signal does not include the geographic information for the plurality of locations recorded in C). 4. The method of claim 1, wherein B) comprises: B1) modulating the test signal so as to mitigate significant interference in the upstream path bandwidth with the first upstream information from the plurality of first subscriber premises. 5. The method of claim 4, wherein B1) comprises spread spectrum modulating the test signal. 6. The method of claim 4, wherein B1) comprises time division multiplexing the test signal. 7. The method of claim 6, wherein: the upstream path bandwidth includes a plurality of time slots;the plurality of time slots include a plurality of subscriber premises time slots and at least one dedicated time slot for the test signal;the plurality of subscriber premises are assigned respective subscriber premises time slots of the plurality of subscriber premises time slots to transmit at least some of the first upstream information in the upstream path bandwidth; andB1) comprises broadcasting the test signal during the dedicated time slot. 8. The method of claim 1, wherein B1) comprises: broadcasting the test signal as at least one pulsed test signal. 9. The method of claim 8, wherein a duration of one or more pulses of the at least one pulsed test signal is less than a symbol length of the first upstream information from the plurality of first subscriber premises. 10. The method of claim 1, wherein B) comprises: during A), broadcasting from the transmitter the test signal at a sufficiently low power as transmitted by the transmitter so as not to require licensure from one or more regulatory authorities. 11. The method of claim 1, wherein B) comprises: during A), broadcasting from the transmitter the test signal at at least one test signal frequency between 5 MHz and 16 MHz. 12. The method of claim 1, wherein B) comprises: during A), varying the at least one test signal frequency, as a function of time, across at least a portion of the upstream path bandwidth. 13. The method of claim 1, wherein: the at least one test signal frequency includes a plurality of test signal frequencies; andB) further comprises:B1) broadcasting, during A), the test signal at the plurality of test signal frequencies. 14. The method of claim 13, wherein B1) comprises broadcasting the test signal at at least two of the plurality of test signal frequencies simultaneously. 15. The method of claim 13, wherein the test signal includes a spread spectrum test signal. 16. The method of claim 1, wherein B) comprises: B1) broadcasting the test signal during operative signaling in the upstream path bandwidth from at least some of the plurality of first subscriber premises, wherein the at least one test signal frequency falls within a frequency range of the operative signaling in the upstream path bandwidth. 17. The method of claim 16, wherein B1) further comprises: varying the at least one test signal frequency, as a function of time, across a substantial portion of the frequency range of the operative signaling in the upstream path bandwidth. 18. The method of claim 1, wherein: C) comprises:during A), electronically recording the first geographic information corresponding to the respective positions of the mobile broadcast apparatus along at least the substantial portion of the first neighborhood node drive path as a first ordered sequence of points so as to generate the first record of the first geographic information as a function of time; andD) comprises:during A) and throughout traversing at least the substantial portion of the first neighborhood node drive path, recording, via the analyzer coupled to the first junction of the cable modem system and the headend optical/RF converter or the second junction of the hardline cable plant and the first node optical/RF converter, the plurality of signal amplitudes at the test signal frequency as a second ordered sequence of points so as to generate the second record, the plurality of signal amplitudes representing the strength of the received upstream test signal as a function of time, based on B) and the test signal ingress of the test signal into the at least one fault in the first RF hardline coaxial cable plant. 19. The method of claim 18, wherein in D), the second ordered sequence of points is indexed to the first ordered sequence of points from C). 20. The method of claim 18, wherein in C) and D), the first ordered sequence of points and the second ordered sequence of points respectively are sampled at a same time. 21. The method of claim 1, wherein: C) comprises:during A), electronically recording the first geographic information corresponding to the respective positions of the mobile broadcast apparatus along at least the substantial portion of the first neighborhood node drive path, together with a plurality of first corresponding time stamps, so as to generate the first record of the first geographic information as a function of time; andD) comprises:during A) and throughout traversing at least the substantial portion of the first neighborhood node drive path, recording, via the analyzer coupled to the first junction of the cable modem system and the headend optical/RF converter or the second junction of the hardline cable plant and the first node optical/RF converter, the plurality of signal amplitudes at the test signal frequency together with a plurality of second corresponding time stamps so as to generate the second record, the plurality of signal amplitudes representing the strength of the received upstream test signal as a function of time, based on B) and the test signal ingress of the test signal into the at least one fault in the first RF hardline coaxial cable plant. 22. The method of claim 21, wherein: at least a first portion of the first neighborhood node drive path includes a first-pass segment and a second-pass segment;based on the first geographic information and plurality of first corresponding time stamps recorded during C), the mobile broadcast apparatus has at least one substantially identical position along the first-pass segment and the second-pass segment, respectively, at different ones of the first corresponding time stamps;the second record includes respective signal amplitudes representing the strength of the received upstream test signal at different ones of the second corresponding time stamps substantially corresponding to the different ones of the first corresponding time stamps representing the at least one substantially identical position of the mobile broadcast apparatus along the first-pass segment and the second-pass segment;the method further comprises:F) electronically processing the respective signal amplitudes in the second record to provide an electronically-processed signal amplitude at the at least one substantially identical position along the first-pass segment and the second-pass segment; andin E), the second representation is based at least in part on the electronically-processed signal amplitude from F). 23. The method of claim 22, wherein: F) comprises determining an average value of the respective signal amplitudes in the second record to provide an averaged signal amplitude at the at least one substantially identical position along the first-pass segment and the second-pass segment; andin E), the second representation is based at least in part on the averaged signal amplitude from F). 24. The method of claim 22, wherein: F) comprises determining a difference value between the respective signal amplitudes in the second record to provide a differential signal amplitude at the at least one substantially identical position along the first-pass segment and the second-pass segment; andin E), the second representation is based at least in part on the differential signal amplitude from F). 25. The method of claim 21, wherein E) comprises: E1) merging the first record and the second record, based at least in part on the plurality of first corresponding time stamps and the plurality of second corresponding time stamps, so as to generate a third record including at least the first geographic information corresponding to respective positions of the mobile broadcast apparatus and the plurality of signal amplitudes representing the strength of the received upstream test signal as a function of time; andE2) generating the first neighborhood node ingress map based at least in part on the third record. 26. The method of claim 25, wherein: E1) comprises:adding to the third record second geographic information relating to additional locations in the first neighborhood node beyond the first neighborhood node drive path so as to generate an expanded third record; andinterpolating the plurality of signal amplitudes representing the strength of the received upstream test signal as a function of time so as to include in the expanded third record estimated signal amplitudes corresponding to the additional locations; andE2) comprises generating the first neighborhood node ingress map based at least in part on the expanded third record. 27. The method of claim 1, wherein in E), the second graphical representation of the plurality of signal amplitudes includes a visual code for at least the plurality of signal amplitudes. 28. The method of claim 27, wherein the second graphical representation comprises a heat map representing the plurality of signal amplitudes. 29. The method of claim 27, wherein the second graphical representation comprises a contour map representing the plurality of signal amplitudes. 30. The method of claim 27, wherein: the visual code comprises a color code including a plurality of colors; andrespective colors of the plurality of colors represent different signal amplitudes of the plurality of signal amplitudes. 31. The method of claim 27, wherein: the visual code comprises a gray-tone scale including a plurality of shades of gray; andrespective shades of gray of the plurality of shades of gray represent different signal amplitudes of the plurality of signal amplitudes. 32. The method of claim 27, wherein the visual code includes at least one of: a plurality of different hatching styles, wherein respective hatching styles of the plurality of different hatching styles represent different signal amplitudes of the plurality of signal amplitudes;a plurality of different shading styles, wherein respective shading styles of the plurality of different shading styles represent different signal amplitudes of the plurality of signal amplitudes; anda plurality of different symbols, wherein respective symbols of the plurality of different symbols represent different signal amplitudes of the plurality of signal amplitudes. 33. The method of claim 1, wherein in E): the first neighborhood node ingress map comprises a graph having a first axis and a second axis;the first graphical representation of the first neighborhood node drive path corresponds to the first axis, wherein a first scale of the first axis represents a distance or a time along the first neighborhood node drive path;a second scale of the second axis represents respective signal amplitude values of the plurality of signal amplitudes; andthe second graphical representation of the plurality of signal amplitudes comprises a plot on the graph of the plurality of signal amplitudes as a function of the distance or the time along the first neighborhood node drive path. 34. The method of claim 1, wherein E) comprises generating the first neighborhood node ingress map as a three-dimensional map having three coordinate axes, and wherein: the first graphical representation of the first neighborhood node drive path is rendered in a first plane of the three-dimensional map, wherein latitude and longitude coordinates for the first geographic information corresponding to the respective positions of the mobile broadcast apparatus are plotted along a first axis and a second axis, respectively, of the three coordinate axes; andthe second graphical representation includes a graph of respective values of the plurality of signal amplitudes, wherein the respective values of the plurality of signal amplitudes are plotted along a third axis of the three coordinate axes. 35. The method of claim 34, wherein the second graphical representation further includes a two-dimensional representation in the first plane of the three-dimensional map, the two-dimensional representation including a visual code for at least the plurality of signal amplitudes rendered. 36. The method of claim 1, wherein: in A), the mobile broadcast apparatus is further equipped with an antenna and a receiver configured to measure ambient ingress;C) further comprises:during A), electronically recording, in tandem with the first geographic information, ambient ingress information corresponding to a strength of the ambient ingress as measured by the receiver along at least the substantial portion of the first neighborhood node drive path; andE) comprises generating the first neighborhood node ingress map to further include a third graphical representation, overlaid on the first and second graphical representations, of the ambient ingress information. 37. The method of claim 1, wherein E) further comprises generating the first neighborhood node ingress map to further include: a third graphical representation, overlaid on the first and second graphical representations, of a cable facilities map showing at least a portion of the infrastructure of the first neighborhood node. 38. The method of claim 1, wherein E) further comprises generating the first neighborhood node ingress map to further include: a third graphical representation, overlaid on the first and second graphical representations, of subscriber information showing respective locations of the plurality of first subscriber premises. 39. The method of claim 38, wherein the third graphical representation includes at least one of a tax map and a parcel map. 40. The method of claim 38, wherein the third graphical representation includes at least one of: at least one first indicator to indicate respective ones of the plurality of first subscriber premises;at least one second indicator to indicate one or more types of cable communication system services provided to the respective ones of the plurality of first subscriber premises;at least one third indicator to indicate a special status of at least one first subscriber premises of the plurality of first subscriber premises; andat least one fourth indicator to indicate respective ones of non-subscriber premises in the first neighborhood node. 41. The method of claim 1, wherein E) further comprises generating the first neighborhood node ingress map to further include: a third graphical representation, overlaid on the first and second graphical representations, of at least one of an aerial image and a street map. 42. The method of claim 1, wherein E) comprises generating the first neighborhood node ingress map as an electronic visual rendering having a plurality of independently selectable and independently viewable layers comprising at least two of: a first layer corresponding to the first graphical representation of the first neighborhood node drive path;a second layer corresponding to the second graphical representation of the plurality of signal amplitudes;a third layer corresponding to a third graphical representation of a cable facilities map showing at least a portion of the infrastructure of the first neighborhood node;a fourth layer corresponding to a fourth representation of subscriber information showing respective locations of the plurality of first subscriber premises;a fifth layer corresponding to a fifth graphical representation of at least one of an aerial image and a street map; anda sixth layer corresponding to a sixth representation of ambient ingress information in the first neighborhood node. 43. The method of claim 1, further comprising: F) during A), electronically communicating to the mobile broadcast apparatus the plurality of signal amplitudes recorded in D) in substantially real time; andG) providing to a technician directing the mobile broadcast apparatus at least one audible indicator and/or at least one visual indicator based on the plurality of signal amplitudes, wherein at least one aspect of the at least one audible indicator and/or the at least one visual indicator is based at least in part on the strength of the received upstream test signal as a function of time. 44. The method of claim 1, further comprising: F) electronically processing the plurality of signal amplitudes so as to automatically determine at least one potential point of first neighborhood node ingress due to the at least one fault in the first RF hardline coaxial cable plant of the first neighborhood node. 45. The method of claim 44, wherein E) comprises: based on the first record in C), the second record generated in D), and the at least one potential point of first neighborhood node ingress determined in F), generating the first neighborhood node ingress map comprising:the first graphical representation of the first neighborhood node drive path;the second graphical representation, overlaid on the first graphical representation, of the plurality of signal amplitudes; anda third graphical representation, overlaid on the first graphical representation and the second graphical representation, of the at least one potential point of first neighborhood node ingress. 46. The method of claim 44, wherein F) further comprises processing the plurality of signal amplitudes so as to automatically determine: a plurality of potential points of first neighborhood node ingress; anda relative severity of the plurality of potential points of first neighborhood node ingress so as to prioritize prospective repair or remediation activities in the first neighborhood node. 47. The method of claim 46, wherein E) further comprises: based on the first record in C), the second record generated in D), and the plurality of potential points of first neighborhood node ingress and the relative severity determined in F), generating the first neighborhood node ingress map comprising:the first graphical representation of the first neighborhood node drive path;the second graphical representation, overlaid on the first graphical representation, of the plurality of signal amplitudes; anda third graphical representation, overlaid on the first graphical representation and the second graphical representation, of the relative severity of the plurality of potential points of first neighborhood node ingress. 48. The method of claim 46, wherein: in A), the mobile broadcast apparatus is further equipped with an antenna and a receiver configured to measure ambient ingress;C) further comprises:during A), electronically recording, in tandem with the first geographic information, ambient ingress information corresponding to a strength of the ambient ingress as measured by the receiver along at least the substantial portion of the first neighborhood node drive path; andF) further comprises processing the plurality of signal amplitudes and the ambient ingress information so as to automatically determine the plurality of potential points of first neighborhood node ingress and the relative severity of the plurality of potential points of first neighborhood node ingress so as to prioritize the prospective repair or remediation activities in the first neighborhood node. 49. The method of claim 46, wherein the plurality of potential points of first neighborhood node ingress comprises: at least one hardline plant-related point corresponding to the at least one hardline plant-related fault in the first RF hardline coaxial cable plant; andat least one subscriber-related point corresponding to at least one subscriber-related fault in at least one of the plurality of first subscriber service drops or at least one of the plurality of first subscriber premises. 50. The method of claim 49, wherein F) further comprises processing the plurality of signal amplitudes and subscriber information so as to automatically determine the relative severity of the plurality of potential points of first neighborhood node ingress so as to prioritize the prospective repair or remediation activities in the first neighborhood node. 51. The method of claim 50, wherein the subscriber information includes at least one of: one or more types of cable communication system services provided to the at least one of the plurality of first subscriber premises; anda special status of the at least one of the plurality of first subscriber premises. 52. The method of claim 49, wherein E) further comprises: based on the first record in C), the second record generated in D), and the plurality of potential points of first neighborhood node ingress and the relative severity determined in F), generating the first neighborhood node ingress map comprising:the first graphical representation of the first neighborhood node drive path;the second graphical representation, overlaid on the first graphical representation, of the plurality of signal amplitudes; anda third graphical representation, overlaid on the first graphical representation and the second graphical representation, of the plurality of potential points of first neighborhood node ingress, wherein the third graphical representation includes different visual codes for the at least one subscriber-related point and the at least one hardline plant-related point, respectively. 53. An apparatus for facilitating detection of ingress in at least a first neighborhood node of a cable communication system, the apparatus comprising: a communication interface;a display device;a memory to store processor-executable instructions;an analyzer; anda processor coupled to the communication interface, the display device, the analyzer, and the memory, wherein upon execution of the processor-executable instructions by the processor, the processor:A) controls the communication interface so as to receive a first record of first geographic information as a function of time, the first geographic information corresponding to respective positions of a mobile broadcast apparatus as directed along at least a substantial portion of a first neighborhood node drive path proximate to a first RF hardline coaxial cable plant in the first neighborhood node of the cable communication system; andB) controls the analyzer to measure a plurality of signal amplitudes representing a strength, at a headend or the first RF hardline coaxial cable plant of the cable communication system, of a received upstream test signal as a function of time, the strength of the received upstream test signal being based on: 1) a test signal broadcast from a transmitter in the mobile broadcast apparatus as the mobile broadcast apparatus is directed along the first neighborhood node drive path proximate to the first RF hardline coaxial cable plant; and 2) test signal ingress of the test signal into at least one fault in the RF hardline coaxial cable plant;C) generates a second record including the plurality of signal amplitudes measured in A2);D) controls the memory so as to store in the memory the first record and the second record;E) based on the first record and the second record, electronically generates a first neighborhood node ingress map comprising:E1) a first graphical representation of the first neighborhood node drive path; andE2) a second graphical representation, overlaid on the first graphical representation, of the plurality of signal amplitudes, at least along the substantial portion of the first neighborhood node drive path, so as to illustrate the test signal ingress of the test signal into at least the first RF hardline coaxial cable plant of the first neighborhood node; andF) controls the display device so as to display the first neighborhood node ingress map. 54. A computer readable non-transitory storage medium storing processor-executable instructions that, when executed by at least one processor, perform a method for facilitating detection of ingress in at least a first neighborhood node of a cable communication system, the method comprising: A) electronically receiving: A1) first geographic information as a function of time, the first geographic information corresponding to respective positions of a mobile broadcast apparatus as directed along at least a substantial portion of a first neighborhood node drive path proximate to a first RF hardline coaxial cable plant in the first neighborhood node of the cable communication system; andA2) a plurality of signal amplitudes representing a strength, as measured at a headend or the first RF hardline coaxial cable plant of the cable communication system, of a received upstream test signal as a function of time, the strength of the received upstream test signal being based on: 1) a test signal broadcast from a transmitter in the mobile broadcast apparatus as the mobile broadcast apparatus is directed along the first neighborhood node drive path proximate to the first RF hardline coaxial cable plant; and 2) test signal ingress of the test signal into at least one fault in the RF hardline coaxial cable plant;B) electronically processing the first geographic information to generate a first record based at least in part on the processed first geographic information;C) electronically processing the plurality of signal amplitudes to generate a second record based at least in part on the processed plurality of signal amplitudes; andD) based on the first record and the second record, electronically generating a first neighborhood node ingress map comprising:D1) a first graphical representation of the first neighborhood node drive path; andD2) a second graphical representation, overlaid on the first graphical representation, of the plurality of signal amplitudes, at least along the substantial portion of the first neighborhood node drive path, so as to illustrate the test signal ingress of the test signal into at least the first RF hardline coaxial cable plant of the first neighborhood node.
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