Abstract: A method of using customer premise cable modem equipment to generate a signal that can be used for leakage detection. Various signal types are described which are usable for the purposes of leakage detection.

Abstract: Signal egress from a shielding flaw in a cable telecommunication system is detected, even where signals carried by the cable telecommunication system are quadrature amplitude modulated signals that statistically resemble broadband noise by generating a marker signal comprising a double side band, suppressed carrier signal in the fringes of contiguous frequency bands and at a power level which cannot cause perceptible interference with signals in those contiguous frequency bands. The separation of the sidebands comprising the marker signal can unambiguously identify the marker signal and can distinguish between different cable telecommunication systems installed in the same geographic area. The marker signal can be additionally coded by varying the frequency and/or amplitude of the modulating signal used to create the marker signal.

Abstract: An improved, adaptive and uniformly applicable estimation of the percentage or fraction of a broadband communication system (BCS) plant that is monitored for signal egress during a given period of time is provided by generating and collecting polygons along all possible routes traversed by BCS service vehicles within a service area, preferably by comparison with a roadway map, to define the service area with improved accuracy. The number of polygons generated and collected is then limited by the number of polygons in which DCS service vehicles have been reported in a given period of time or inspection interval. The limited number of polygons is then divided by the number of polygons generated and collected to determine a fraction or percentage of the BCS system which has been monitored during the given time period and can be used in a computation of a cumulative leakage index (CLI) value.

Abstract: A small, portable signal generator provides a unique marker signal modulated with a selectable number of degrees of freedom for insertion into a portion of a broadband communication system (BCS) such as a subscriber installation site that may or may not be connected to the remainder of the BCS. If payload signals are not present or brief interference with payload signals is tolerable, a high level marker signal may be injected with level control upon detection of an egress signal to detect very minor leakage sources and thus increase quality of the qualification of installation or repairs. If payload signals are present, marker signals are held to non-interfering levels and frequencies. Authentication of a signal received through an antenna is expedited and increased in confidence level by synchronization of the marker signal modulation pattern and the signal detector in a receiver.

Abstract: A cyclic prefix which duplicates some samples of a terminal portion of a symbol in an OFDM data stream and which is invariant in pilot tones can be detected in the presence of signals having higher levels of noise and broadcast signals by autocorrelation with one of two selected “lags”. Autocorrelation will be found when the lag is equal to the number of samples in the FFT used to form a symbol in the data stream. A far stronger autocorrelation is found when the lag is equal to the sum of the FFT length and the length of the cyclic prefix and applied to pilots in the data stream. Overbuilt systems can be distinguished from a system of interest by use of pilots that do not coincide in frequency with a pilot of an overbuilt system.

Abstract: An egress signal from a broadband communication system (BCS) including orthogonal frequency division multiplex (OFDM) signals is distinguished from noise and broadcast transmissions and authenticated as such by detecting required or optional pilot signals by their frequency, pattern and/or other characteristics such as recurrence rate or cepstral interval. Detection is made more robust by detection of combinations of required or optional pilot tones. Different BCS plants in the same geographic area or overbuilt can be discriminated based on the frequencies and frequency intervals of required, fixed frequency PHY link channel (PLC) related pilots, pattern and frequency of the presence or absence of optional pilots at fixed frequency intervals and/or cepstral or recurrence intervals of required scattered pilots if different symbol rates are employed or frequency of scattered pilots if the OFDM bands do not overlap in the adjacent or overbuilt BCSs.

Abstract: Passive detection of a quadrature amplitude modulated (QAM) signal amid noise is achieved by detection of a spectral component of a detected signal that corresponds to a known QAM symbol rate in, for example, a QAM modulated broadband communication system (BCS). Improved authentication can be provided by simultaneously detecting symbol rate components in two or more QAM bands. No modification of a broadband communication system such as by including a marker signal is required and thus there is no requirement for dedication of a portion of the broadband communication system spectrum or problem of marker signal interference with BCS signals.

Abstract: A method and structure for conforming to cable leakage compliance level requirements includes calculating, using a processor on a computer, a priority of repairs for cable leakage over a cable operator service area. A result of the priority calculation is provided, thereby permitting higher priority leaks to be identified and repaired. The calculating of priority includes storing geographical locations of cell towers affecting a service area being evaluated, receiving data related to cable leakage sources, receiving data related to wireless service quality, if available, and exercising, using the processor on the computer, a prioritizing algorithm that calculates a relative severity of each cable leakage source.

Abstract: Signal ingress at an installations site forming a part of a broadband communication system is quantitatively evaluated for resistance to signal ingress using a computed ambient broadcast signal level based on a known location and effective radiated power of one or more transmitters. Anomalies due to signal path obstruction and/or multi-path reception are compensated by performing computations for a plurality of broadcast transmitters located in different directions from the installation site.

Abstract: Results of field testing of portions of a distributed system such as a Broadband Communications System are communicated from a testing device to a device including a display which downloads test protocols to the testing device. The testing device can thereafter operate in a stand-alone manner and transfer the results of testing and analysis to a device including a display that may comprise virtually any wireless communication device by storing an application or information therein. The communication device can transfer captured test data and analysis to a central facility for storage, further analysis and/or management purposes.

Abstract: An improved, adaptive and uniformly applicable estimation of the percentage or fraction of a broadband communication system (BCS) plant that is monitored for signal egress during a given period of time is provided by generating and collecting polygons along all possible routes traversed by DOS service vehicles within a service area, preferably by comparison with a roadway map, to define the service area with improved accuracy. The number of polygons generated and collected is then limited by the number of polygons in which DCS service vehicles have been reported in a given period of time or inspection interval. The limited number of polygons is then divided by the number of polygons generated and collected to determine a fraction or percentage of the BCS system which has been monitored during the given time period and can be used in a computation of a cumulative leakage index (CLI) value.

Abstract: Signal egress from a shielding flaw in a cable telecommunication system is detected, even where signals carried by the cable telecommunication system are quadrature amplitude modulated signals that statistically resemble broadband noise by generating a marker signal comprising a double side band, suppressed carrier signal in the fringes of contiguous frequency bands and at a power level which cannot cause perceptible interference with signals in those contiguous frequency bands. The separation of the sidebands comprising the marker signal can unambiguously identify the marker signal and can distinguish between different cable telecommunication systems installed in the same geographic area. The marker signal can be additionally coded by varying the frequency and/or amplitude of the modulating signal used to create the marker signal.

Abstract: Passive detection of a quadrature amplitude modulated (QAM) signal amid noise is achieved by detection of a spectral component of a detected signal that corresponds to a known QAM symbol rate in, for example, a QAM modulated broadband communication system (BCS). Improved authentication can be provided by simultaneously detecting symbol rate components in two or more QAM bands. No modification of a broadband communication system such as by including a marker signal is required and thus there is no requirement for dedication of a portion of the broadband communication system spectrum or problem of marker signal interference with BCS signals.

Abstract: A method and structure for conforming to cable leakage compliance level requirements includes calculating, using a processor on a computer, a priority of repairs for cable leakage over a cable operator service area. A result of the priority calculation is provided, thereby permitting higher priority leaks to be identified and repaired. The calculating of priority includes storing geographical locations of cell towers affecting a service area being evaluated, receiving data related to cable leakage sources, receiving data related to wireless service quality, if available, and exercising, using the processor on the computer, a prioritizing algorithm that calculates a relative severity of each cable leakage source.

Abstract: Detecting ingress of a transmitted signal into a cable communication system due to a radio frequency signal transmitted from a moving vehicle and interrogation of transmitter location over a separate wireless link provides monitoring of shielding integrity or flaws there in a cable communication system. The location of a shielding flaw may then be precisely located in a closed loop fashion without risking overload of the cable communication system or interference with upstream signaling therein by detecting ingress signal strength and controlling transmitted signal strength while providing a user-perceptible indication of ingress signal strength which is compensated for the control of transmitted signal strength and thus indicates proximity of a hand-held instrument or transmitter to said shielding flaw.

Abstract: Results of field testing of portions of a distributed system such as a Broadband Communications System from a testing device to a controller which downloads programmed test protocols and sequences thereof to the separate testing device over a wired or wireless link and thereafter can be used to control the testing device as well as display test results and provide analysis of the test results and suggest procedures to technical personnel. The controller then can transmit the test data to a central facility or distribution hub in substantially real-time together with work performance data where full technical analysis can be performed. The test data and results of analysis can then be distributed as desired such as to a management analysis facility to support improvement of efficiency of the system and the operation thereof.

Abstract: Issuance of work orders in response to monitoring signal egress from shielding integrity flaws in a cable communication system by detecting received signal strength from a mobile receiver only during rising trends in received signal strength when the mobile receiver is in motion and tracking the maximum received signal strength peak during each rising trend. Rising trends are detected by computing two rolling averages of received signal strength sample of different lengths and offset from each other and applying a threshold to the difference between the rolling averages to provide hysteresis in switching between rising and falling trend detection. Reported peaks are then compared by proximity to each other and their circle of influence determined in accordance with respective signal strengths to determine if newly reported peaks are duplicates of previously reported peaks and duplicate reported peaks are removed or discarded.

Abstract: A system and method of validating signals and detecting signal leakage in a cable communications includes the steps of a) tuning a radio frequency receiver to a carrier frequency of a selected RF channel, b) measuring a signal level of the carrier frequency, c) off-tuning the receiver by a predetermined offset, d) measuring a signal level of the off-tuned carrier frequency, e) obtaining a signal level difference between the signal level of the carrier frequency and the signal level of the off-tuned carrier frequency to determine if interference exists, f) declaring an interference condition if the signal level difference is less than a predetermined difference amount, and g) providing an indication of the signal level of the carrier frequency to permit a determination of whether a signal leakage condition exists.

Abstract: An arbitrary number of signaling beacons are synchronized simultaneously and automatically by a received modulated control signal in accordance with an arbitrary communication protocol over a communication link which may be separate from or superimposed upon a perceptible signal periodically provided from signaling beacons. The periodic perceptible signal may be stabilized using a crystal oscillator or an external transmitted signal such as a global positioning system (GPS) signal and synchronization thus maintained for extended periods of time even when the synchronization communication link is not available. Interference is substantially prevented by the communication protocol while supporting the provision of any desired beacon control functions.

Abstract: A method and apparatus are provided for determining a source of a leakage signal from a distribution cable of a cable television distribution system. The method includes the steps of sampling the leakage signal from the distribution cable of the cable television distribution system at each of a plurality of geographic locations within an environs of the cable, forming a leakage signal profile relating each sample with a respective location of the plurality of geographic locations; and determining a source location of the leakage signal based upon the formed profile.