US5754437A
Expired / Lapsed
US
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Phase measurement apparatus and method
Assignee: Tektronix Inc
•
Filing: 1996-09-10
•
Granted: 1998-05-19
•
Expires: 2016-09-10
Abstract
Abstract A phase measurement apparatus and method for measuring electrical signal jitter and wander operates in real time and digitally controls bandwidths over which the measurements are performed. The apparatus includes a digital phase-lock loop (PLL) for generating phase difference signal data having first and second frequency components above and below the loop bandwidth of the phase locked loop. An analog-to-digital converter digitizes the analog phase difference signal from the phase detector. A digital signal processor (DSP) receives the digital data and performs a loop filter function for generating frequency update values to the DDS for phase locking the PLL to an incoming signal. The DSP performs an integration function on the loop filter function output to generate the second frequency components. The first and second frequency components are combined in a summing circuit and filtered in digitally programmable low and high pass filters for establishing measurement bands for measuring the phase difference. A measurement processor measures peak-to-peak minimum and maximum values and generates RMS values of the phase difference signal over a selected time interval and generating an output in unit intervals for jitter and time for wander. The DSP further includes low and high pass filter functions and an accumulator for summing filtered second frequency components to generate wander data. The DSP processes the frequency update values to generate frequency drift data.\!
Inventors
- 👤 Stephen F. Blazo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:58
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/20; H04L1/205
Claims Analysis
Total Claims: 114
Claim 1
Independent Claim
241 words
An apparatus for measuring phase difference between a first signal having a first frequency and a second signal having a second frequency comprising: a reference clock; a phase-locked-loop having a loop bandwidth including; a digital signal processor; a digitally controlled frequency source generating in response to the reference clock and the digital signal processor the second signal having the second frequency; a phase detector receiving the first and second signals and generating a phase difference signal proportional to a phase difference between the first and second frequencies with the phase difference signal having first frequency components representing the phase difference above the loop bandwidth of the phase-locked-loop; and an analog-to-digital converter digitizing the phase difference signal to generate phase difference signal data having the first frequency components of the phase difference signal with the phase difference signal data being coupled to the digital signal processor for processing the phase difference signal data to produce second frequency components representing the phase difference below the loop bandwidth of the phase-locked loop and providing frequency control data to the digitally controlled frequency source such that the first and second frequencies are in a phase-locked condition; means for combining the phase difference signal data from the analog-to-digital converter and the processed phase difference signal data from the digital signal processor representing the first and second frequency components of the phase difference signal; and means for measuring the phase difference between the first and second signals.
Claim 2
Independent Claim
241 words
An apparatus for measuring phase difference between a first signal having a first frequency and a second signal having a second frequency comprising: a reference clock; a phase-locked-loop having a loop bandwidth including; a digital signal processor; a digitally controlled frequency source generating in response to the reference clock and the digital signal processor the second signal having the second frequency; a phase detector receiving the first and second signals and generating a phase difference signal proportional to a phase difference between the first and second frequencies with the phase difference signal having first frequency components representing the phase difference above the loop bandwidth of the phase-locked-loop; and an analog-to-digital converter digitizing the phase difference signal to generate phase difference signal data having the first frequency components of the phase difference signal with the phase difference signal data being coupled to the digital signal processor for processing the phase difference signal data to produce second frequency components representing the phase difference below the loop bandwidth of the phase-locked loop and providing frequency control data to the digitally controlled frequency source such that the first and second frequencies are in a phase-locked condition; means for combining the phase difference signal data from the analog-to-digital converter and the processed phase difference signal data from the digital signal processor representing the first and second frequency components of the phase difference signal; and means for measuring the phase difference between the first and second signals.
Claim 3
Dependent Claim
47 words
The apparatus as recited in claim 1 wherein the digitally controlled frequency source comprises a direct digital synthesizer, a tracking oscillator, and a prescaler that cooperate to generate the second frequency when the first frequency is substantially greater than a frequency generated by the direct digital synthesizer.
Claim 4
Dependent Claim
43 words
The apparatus as recited in claim 1 wherein the digital signal processor executes at least one of a loop filter function, an integration function, a low pass filter function, a high pass filter function, an out-of-lock detection function and a frequency drift function.
Claim 5
Dependent Claim
30 words
The apparatus as recited in claim 3 wherein the loop filter function comprises a loop breakpoint that is programmable in a range from about 500 Hertz to about 1 Kilohertz.
Claim 6
Dependent Claim
34 words
The apparatus as recited in claim 3 wherein the frequency drift function comprises differentiating the frequency control data coupled to the digitally controlled frequency source and filtering in range from zero to 0.5 Hertz.
Claim 7
Dependent Claim
57 words
The apparatus as recited in claim 1 further comprising a clock recovery circuit that receives an incoming signal and produces the first signal, the incoming signal being of a type selected from a group consisting of a nonreturn-to-zero formatted signal, a return-to-zero formatted signal, a code-mark-inversion formatted signal, an alternate-mark-inversion formatted signal, and a clock input signal.
Claim 8
Dependent Claim
34 words
The apparatus as recited in claim 6 further comprising an incoming signal prescaler and in which the incoming signal has a signaling rate in a frequency range up to about 2.5 Gigabits per second.
Claim 9
Dependent Claim
16 words
The apparatus as recited in claim 1 wherein the combining means comprises a digital summing node.
Claim 10
Dependent Claim
34 words
The apparatus as recited in claim 8 wherein the digital summing node comprises an accumulator for summing the phase difference signal data representing the first and second frequency components of the phase difference signal.
Claim 11
Dependent Claim
39 words
The apparatus as recited in claim 9 wherein the digital summing node performs a RMS function over a selected time interval on the phase difference signal data representing the first and second frequency components of the phase difference signal.
Claim 12
Dependent Claim
60 words
The apparatus as recited in claim 1 wherein the measuring means comprises: means for implementing selected frequency bands for measuring the phase difference; and means for measuring peak-to-peak and RMS phase difference data amplitudes for at least one of an amount of jitter and filtered phase difference values over time of the second frequency components for an amount of wander.
Claim 13
Dependent Claim
56 words
The apparatus as recited in claim 11 wherein the frequency bands implementing means comprises serially coupled digitally programmable low and high pass filters implementing low and high pass filter functions and coupled to receive the combined phase difference signal data representing the first and second frequency components of the phase difference signal from the combining means.
Claim 14
Dependent Claim
79 words
The apparatus as recited in claim 11 wherein the measuring means comprises a processor having an accumulator for storing minimum and maximum peak-to-peak values of the filtered phase difference data amplitudes over a first time interval and performing a RMS function on the phase difference data amplitudes over the first time interval for generating RMS values and summing filtered phase difference data amplitudes of the second frequency components over a second time interval from the frequency band implementing means.
Claim 15
Dependent Claim
32 words
The apparatus as recited in claim 13 further comprising means for generating a wander measurement output as a function of time and a jitter measurement output as a function of unit intervals.
Claim 16
Dependent Claim
16 words
The apparatus as recited in claim 14 wherein the generating means comprises the digital signal processor.
Claim 17
Dependent Claim
15 words
The apparatus as recited in claim 14 wherein the generating means comprises a system processor.
Claim 18
Dependent Claim
33 words
The apparatus as recited in claim 12 wherein the digitally programmable high pass filter function further comprises a breakpoint that is programmable in a range from about 0.1 Hertz to about 250 Kilohertz.
Claim 19
Dependent Claim
44 words
The apparatus as recited in claim 17 wherein the digitally programmable high pass filter function breakpoint is continuously programmable in a range from about 0.1 Hertz to about 20 Hertz and selectively programmable in a range from about 100 Hertz to about 250 Kilohertz.
Claim 20
Dependent Claim
29 words
The apparatus as recited in claim 17 wherein the digitally programmable high pass filter function breakpoint is selectively programmable in steps from about 0.1 Hertz to about 250 Kilohertz.
Claim 21
Dependent Claim
32 words
The apparatus as recited in claim 12 wherein the digitally programmable low pass filter function comprises a breakpoint that is programmable in the range from about 10 Hertz to about 5 Megahertz.
Claim 22
Dependent Claim
26 words
The apparatus as recited in claim 20 wherein the digitally programmable low pass filter further includes a decimating digital filter having a predetermined low pass breakpoint.
Claim 23
Dependent Claim
27 words
The apparatus as recited in claim 21 wherein the decimating digital filter includes at least a boxcar averaging decimating digital filter and a finite impulse response filter.
Claim 24
Dependent Claim
39 words
The apparatus as recited in claim 11 wherein the amount of wander is measured in a wander band and the amount of jitter is measured in at least one of a subband, a wideband, a fullband, and a highband.
Claim 25
Dependent Claim
23 words
The apparatus as recited in claim 23 wherein the wander band spans a frequency range from about zero Hertz to about 10 Hertz.
Claim 26
Dependent Claim
22 words
The apparatus as recited in claim 23 wherein the subband spans a frequency range from about 0.1 Hertz to about 1 Kilohertz.
Claim 27
Dependent Claim
22 words
The apparatus as recited in claim 23 wherein the wideband spans a frequency range from about 10 Hertz to about 5 Megahertz.
Claim 28
Dependent Claim
22 words
The apparatus as recited in claim 23 wherein the fullband spans a frequency range from about 0.1 Hertz to about 5 Megahertz.
Claim 29
Dependent Claim
22 words
The apparatus as recited in claim 23 wherein the highband spans a frequency range from about 700 Hertz to about 5 Megahertz.
Claim 30
Dependent Claim
131 words
The apparatus as recited in claim 11 wherein the measuring means includes the digital signal processor executing a loop filter function and an integration function on the phase difference signal data and low and high pass filter functions on the processed phase difference signal data and having an accumulator for summing filtered phase difference data amplitudes of the second frequency components over a first time interval for the amount of wander and a processor having an accumulator for storing minimum and maximum peak-to-peak values of the filtered phase difference data amplitudes over a second time interval and performing a RMS function on the phase difference data amplitudes over the second time interval for generating RMS values from the frequency band implementing means for at least one of the amount of jitter.
Claim 31
Dependent Claim
33 words
The apparatus as recited in claim 29 wherein the digital signal processor loop filter function comprising a loop breakpoint that is programmable in a range from about 500 Hertz to about 1 Kilohertz.
Claim 32
Dependent Claim
33 words
The apparatus as recited in claim 29 wherein the digital signal processor low pass filter function includes a breakpoint that is programmable from a range of about 10 Hertz to about 20 Hertz.
Claim 33
Dependent Claim
33 words
The apparatus as recited in claim 29 wherein the digital signal processor highpass filter function includes a breakpoint that is continuously programmable from a range of about 0.1 Hertz to about 20 Hertz.
Claim 34
Dependent Claim
34 words
The apparatus as recited in claim 29 wherein the digital signal processor high pass filter function includes a breakpoint that is selectively programmable from a range of about 0.1 Hertz to about 20 Hertz.
Claim 35
Dependent Claim
29 words
The apparatus as recited in claim 29 wherein the amount of wander measurable on the first signal is in a range from about zero milliseconds to about ±10 milliseconds.
Claim 36
Dependent Claim
31 words
The apparatus as recited in claim 29 wherein the amount of jitter measurable on the first signal is in a range from about zero unit intervals to about ±256 unit intervals.
Claim 37
Dependent Claim
32 words
The apparatus as recited in claim 29 further comprising means for generating a wander measurement output as a function of time and a jitter measurement output as a function of unit intervals.
Claim 38
Dependent Claim
16 words
The apparatus as recited in claim 36 wherein the generating means comprises the digital signal processor.
Claim 39
Dependent Claim
15 words
The apparatus as recited in claim 37 wherein the generating means comprises a system processor.
Claim 40
Dependent Claim
39 words
The apparatus as recited in claim 29 wherein the amount of wander is measured in a wander band and the amount of jitter is measured in at least one of a subband, a wideband, a fullband, and a highband.
Claim 41
Dependent Claim
23 words
The apparatus as recited in claim 39 wherein the wander band spans a frequency range from about zero Hertz to about 10 Hertz.
Claim 42
Dependent Claim
22 words
The apparatus as recited in claim 39 wherein the subband spans a frequency range from about 0.1 Hertz to about 1 Kilohertz.
Claim 43
Dependent Claim
22 words
The apparatus as recited in claim 39 wherein the wideband spans a frequency range from about 10 Hertz to about 5 Megahertz.
Claim 44
Dependent Claim
22 words
The apparatus as recited in claim 39 wherein the fullband spans a frequency range from about 0.1 Hertz to about 5 Megahertz.
Claim 45
Dependent Claim
21 words
The apparatus as recited in claim 39 wherein the highband spans a frequency range from about 700 to about 5 Megahertz.
Claim 46
Dependent Claim
86 words
The apparatus as recited in claim 11 wherein the frequency bands implementing means comprises digitally programmable low and high pass filters implementing low and high pass filter functions with the low pass filter coupled to receive the phase difference signal data from the analog-to-digital converter representing the first frequency components of the phase difference signal and the high pass filter is coupled to receive the combined phase difference signal data representing the first and second frequency components of the phase difference signal from the combining means.
Claim 47
Dependent Claim
33 words
The apparatus as recited in claim 45 wherein the digitally programmable low pass filter includes a low pass breakpoint that is programmable in a range from about 40 Kilohertz to about 5 MHZ.
Claim 48
Dependent Claim
20 words
The apparatus as recited in claim 46 wherein the digitally programmable low pass filter further includes a decimating digital filter.
Claim 49
Dependent Claim
27 words
The apparatus as recited in claim 47 wherein the decimating digital filter includes at least a boxcar averaging decimating digital filter and a finite impulse response filter.
Claim 50
Dependent Claim
32 words
The apparatus as recited in claim 45 wherein the digitally programmable high pass filter function includes a breakpoint that is programmable in a range from about 100 Hertz to about 250 Kilohertz.
Claim 51
Independent Claim
362 words
An apparatus for measuring at least one of an amount of jitter and an amount of wander present on a first signal having a first frequency, comprising: a reference clock; a phase-locked-loop having a loop bandwidth including; a digital signal processor executing at least one of a loop filter function, an integration function, a low pass filter function, a high pass filter function, and an out-of-lock detection function; a digitally controlled frequency source generating in response to the reference clock and the digital signal processor a second signal having a second frequency; a phase detector receiving the first and second signals and generating a phase difference signal proportional to a phase difference between the first and second frequencies with the phase difference signal having first frequency components representing the phase difference above the loop bandwidth of the phase-locked-loop; and an analog-to-digital converter digitizing the phase difference signal to generate phase difference signal data having the first frequency components of the phase difference signal with the phase difference signal data being coupled to the digital signal processor for executing the loop filter and integration functions on the phase difference signal data to produce second frequency components representing the phase difference below the loop bandwidth of the phase-locked loop and providing frequency control data to the digitally controlled frequency source such that the first and second frequencies are in a phase-locked condition, the digital signal processor further executing the low and high pass filter functions on the integrated phase difference signal data; a digitally programmable low pass filter coupled to the analog-to-digital converter for implementing a low pass filter function on the phase difference signal data representing the first frequency components; a summation circuit for summing the low pass filtered phase difference signal data from the digitally programmable low pass filter and the filtered integrated phase difference signal data from the digital signal processor; a digitally programmable high pass filter coupled to receive the output of the summing circuit for implementing a high pass filter function on the summed phase difference signal data; and means for measuring at least one of the amount of jitter and the amount of wander on the first signal.
Claim 52
Independent Claim
362 words
An apparatus for measuring at least one of an amount of jitter and an amount of wander present on a first signal having a first frequency, comprising: a reference clock; a phase-locked-loop having a loop bandwidth including; a digital signal processor executing at least one of a loop filter function, an integration function, a low pass filter function, a high pass filter function, and an out-of-lock detection function; a digitally controlled frequency source generating in response to the reference clock and the digital signal processor a second signal having a second frequency; a phase detector receiving the first and second signals and generating a phase difference signal proportional to a phase difference between the first and second frequencies with the phase difference signal having first frequency components representing the phase difference above the loop bandwidth of the phase-locked-loop; and an analog-to-digital converter digitizing the phase difference signal to generate phase difference signal data having the first frequency components of the phase difference signal with the phase difference signal data being coupled to the digital signal processor for executing the loop filter and integration functions on the phase difference signal data to produce second frequency components representing the phase difference below the loop bandwidth of the phase-locked loop and providing frequency control data to the digitally controlled frequency source such that the first and second frequencies are in a phase-locked condition, the digital signal processor further executing the low and high pass filter functions on the integrated phase difference signal data; a digitally programmable low pass filter coupled to the analog-to-digital converter for implementing a low pass filter function on the phase difference signal data representing the first frequency components; a summation circuit for summing the low pass filtered phase difference signal data from the digitally programmable low pass filter and the filtered integrated phase difference signal data from the digital signal processor; a digitally programmable high pass filter coupled to receive the output of the summing circuit for implementing a high pass filter function on the summed phase difference signal data; and means for measuring at least one of the amount of jitter and the amount of wander on the first signal.
Claim 53
Dependent Claim
57 words
The apparatus as recited in claim 50 further including a clock recovery circuit that receives an incoming signal and produces the first signal, the incoming signal being of a type selected from a group consisting of a nonreturn-to-zero formatted signal, a return-to-zero formatted signal, a code-mark-inversion formatted signal, an alternate-mark-inversion formatted signal, and a clock input signal.
Claim 54
Dependent Claim
34 words
The apparatus as recited in claim 51 further including an incoming signal prescaler and in which the incoming signal has a signaling rate in a frequency range up to about 2.5 Gigabits per second.
Claim 55
Dependent Claim
48 words
The apparatus as recited in claim 50 in which the digitally controlled frequency source includes a direct digital synthesizer, a tracking oscillator, and a prescaler that cooperate to generate the second frequency when the first frequency is substantially greater than a frequency generated by the direct digital synthesizer.
Claim 56
Dependent Claim
20 words
The apparatus as recited in claim 50 in which the digital signal processor further comprises executing a frequency drift function.
Claim 57
Dependent Claim
36 words
The apparatus as recited in claim 54 in which the frequency drift function comprises differentiating the frequency control data coupled to the digitally controlled frequency source and filtering in a range from zero to 0.5 Hertz.
Claim 58
Dependent Claim
109 words
The apparatus as recited in claim 50 in which the measuring means includes the digital signal processor having an accumulator for summing filtered phase difference data amplitudes of the second frequency components over a first time interval for the amount of wander and a processor having an accumulator for storing minimum and maximum peak-to-peak values of the filtered phase difference data amplitudes over a second time interval and performing a RMS function on the phase difference data amplitudes over the second time interval for generating RMS values of the phase difference signal data from the digitally programmable high pass filter for at least one of the amount of jitter.
Claim 59
Dependent Claim
32 words
The apparatus as recited in claim 56 further including means for generating a wander measurement output as a function of time and a jitter measurement output as a function of unit intervals.
Claim 60
Dependent Claim
16 words
The apparatus as recited in claim 57 wherein the generating means comprises the digital signal processor.
Claim 61
Dependent Claim
15 words
The apparatus as recited in claim 57 wherein the generating means comprises a system processor.
Claim 62
Dependent Claim
35 words
The apparatus as recited in claim 50 in which the digital signal processor high pass filter function includes a breakpoint that is continuously programmable in a range from about 0.1 Hertz to about 20 Hertz.
Claim 63
Dependent Claim
35 words
The apparatus as recited in claim 50 in which the digital signal processor high pass filter function includes a breakpoint that is selectively programmable from a range of about 0.1 Hertz to about 20 Hertz.
Claim 64
Dependent Claim
34 words
The apparatus as recited in claim 50 in which the digital signal processor low pass filter function includes a breakpoint that is programmable in the range from about 10 Hertz to about 20 Hertz.
Claim 65
Dependent Claim
34 words
The apparatus as recited in claim 50 in which the digital signal processor loop filter function includes a loop breakpoint that is programmable in a range from about 500 Hertz to about 1 Kilohertz.
Claim 66
Dependent Claim
34 words
The apparatus as recited in claim 50 in which the digitally programmable high pass filter function further includes a breakpoint that is programmable in a range from about 100 Hertz to about 250 Kilohertz.
Claim 67
Dependent Claim
46 words
The apparatus as recited in claim 50 in which the digitally programmable low pass filter function further includes a decimating digital filter implementing a finite impulse response filter function having a breakpoint that is programmable in a range from about 40 Kilohertz to about 5 Megahertz.
Claim 68
Dependent Claim
28 words
The apparatus as recited in claim 65 in which the decimating digital filter includes at least a boxcar averaging decimating digital filter and a finite impulse response filter.
Claim 69
Dependent Claim
41 words
The apparatus as recited in claim 50 in which the amount of wander is measured in a wander band and the amount of jitter is simultaneously measured in at least one of a subband, a wideband, a fullband, and a highband.
Claim 70
Dependent Claim
24 words
The apparatus as recited in claim 67 in which the wander band spans a frequency range from about zero Hertz to about 10 Hertz.
Claim 71
Dependent Claim
23 words
The apparatus as recited in claim 67 in which the subband spans a frequency range from about 0.1 Hertz to about 1 Kilohertz.
Claim 72
Dependent Claim
23 words
The apparatus as recited in claim 67 in which the wideband spans a frequency range from about 10 Hertz to about 5 Megahertz.
Claim 73
Dependent Claim
23 words
The apparatus as recited in claim 67 in which the fullband spans a frequency range from about 0.1 Hertz to about 5 Megahertz.
Claim 74
Dependent Claim
22 words
The apparatus as recited in claim 67 in which the highband spans a frequency range from about 700 to about 5 Megahertz.
Claim 75
Independent Claim
204 words
A method for measuring a phase difference between a first signal having a first frequency and a second signal having a second frequency comprising the steps of: receiving the first signal; generating the second signal having the second frequency with a digitally controlled frequency source being a part of a phase-locked-loop having a loop bandwidth; producing with a phase detector a phase difference signal indicative of a phase difference between the first and second frequencies with the phase difference signal having first frequency components representing the phase difference above the loop bandwidth of the phase-locked-loop; digitizing the phase difference signal to generate phase difference signal data having the first frequency components of the phase difference signal; processing digitally the phase difference signal data to produce second frequency components below the loop bandwidth of the phase-locked-loop and provide frequency correction data to the digitally controlled frequency source such that the first and second frequencies are in a phase-locked condition; combining the phase difference signal data representing the first frequency components above the loop bandwidth with the processed second frequency components below the loop bandwidth; and processing the combined phase difference signal data to measure the phase difference between the first signal and the second signal.
Claim 76
Independent Claim
204 words
A method for measuring a phase difference between a first signal having a first frequency and a second signal having a second frequency comprising the steps of: receiving the first signal; generating the second signal having the second frequency with a digitally controlled frequency source being a part of a phase-locked-loop having a loop bandwidth; producing with a phase detector a phase difference signal indicative of a phase difference between the first and second frequencies with the phase difference signal having first frequency components representing the phase difference above the loop bandwidth of the phase-locked-loop; digitizing the phase difference signal to generate phase difference signal data having the first frequency components of the phase difference signal; processing digitally the phase difference signal data to produce second frequency components below the loop bandwidth of the phase-locked-loop and provide frequency correction data to the digitally controlled frequency source such that the first and second frequencies are in a phase-locked condition; combining the phase difference signal data representing the first frequency components above the loop bandwidth with the processed second frequency components below the loop bandwidth; and processing the combined phase difference signal data to measure the phase difference between the first signal and the second signal.
Claim 77
Dependent Claim
20 words
The method of claim 73 further including receiving an incoming signal and recovering the first signal from the incoming signal.
Claim 78
Dependent Claim
16 words
The method of claim 74 in which the recovering step further includes prescaling the incoming signal.
Claim 79
Dependent Claim
30 words
The method of claim 75 in which the incoming signal is a digitally formatted signal having a signaling rate in a frequency range up to about 2.5 Gigabits per second.
Claim 80
Dependent Claim
45 words
The method of claim 73 in which the generating step further includes generating in response to the frequency correction data a submultiple of the second frequency and producing the second signal by tracking an oscillator to a multiple of the submultiple of the second frequency.
Claim 81
Dependent Claim
60 words
The method of claim 73 in which the digitally processing step further includes at least one of loop filtering the phase difference signal data, integrating the phase difference signal data, low pass filtering the phase difference signal data, high pass filtering the phase difference signal data, detecting in the phase difference signal data an out-of-lock condition, and determining frequency drift.
Claim 82
Dependent Claim
37 words
The method of claim 78 in which the frequency drift determining step includes the steps of differentiating the frequency correction data and filtering the differentiated data over a range from about zero Hertz to about 0.5 Hertz.
Claim 83
Dependent Claim
30 words
The method of claim 78 in which the loop filtering step further includes setting digitally a low pass breakpoint in a range from about 500 Hertz to about 1 Kilohertz.
Claim 84
Dependent Claim
30 words
The method of claim 73 in which the combining step further includes summing the phase difference signal data representing the first and second frequency components of the phase difference signal.
Claim 85
Dependent Claim
65 words
The method of claim 73 in which the processing step further includes: implementing selected frequency bands for measuring the phase difference; and measuring peak-to-peak and RMS phase difference data amplitudes over a first time interval for at least one of an amount of jitter and filtered phase difference data amplitudes of the second frequency components over a second time interval for an amount of wander.
Claim 86
Dependent Claim
25 words
The method of claim 82 in which the implementing step further includes implementing low and high pass filter functions using low and high pass filters.
Claim 87
Dependent Claim
31 words
The method of claim 83 in which the high pass filtering function further includes setting digitally a high pass breakpoint in a range from about 0.1 Hertz to about 250 Kilohertz.
Claim 88
Dependent Claim
48 words
The method of claim 84 in which the digitally setting step includes continuously setting the high pass filter function in a range from about 0.1 Hertz to about 20 Hertz and selectively setting the high pass filter function in ranges of about 100 Hertz to about 250 Kilohertz.
Claim 89
Dependent Claim
28 words
The method of claim 84 in which the digitally setting step includes setting the high pass filter function in steps from about 0.1 Hertz to about 250 Kilohertz.
Claim 90
Dependent Claim
28 words
The method of claim 83 in which the low pass filtering function further includes digitally setting a boxcar averaging decimating digital filter and a finite impulse response filter.
Claim 91
Dependent Claim
75 words
The method of claim 82 in which the measuring step further includes storing minimum and maximum peak-to-peak values of filtered phase difference data amplitudes over the first time interval and summing and executing a RMS function on and filtered phase difference data amplitudes over the first time interval for generating RMS values and summing filtered phase difference data amplitudes of the second frequency components over the second time interval from the frequency band implementing means.
Claim 92
Dependent Claim
33 words
The method of claim 88 in which the measuring step further includes generating a wander measurement output as a function of time and a jitter measurement output as a function of unit intervals.
Claim 93
Dependent Claim
44 words
The method of claim 83 further including the step of filtering digitally at predetermined low and high pass breakpoints the combined phase difference signal data to measure the amount of wander and at least one of the amount of jitter on the first signal.
Claim 94
Dependent Claim
45 words
The method of claim 90 in which the filtering of the combined phase difference signal data step further includes measuring the amount of wander present on the first signal in a wander band having a frequency range from about zero Hertz to about 10 Hertz.
Claim 95
Dependent Claim
44 words
The method of claim 90 in which the filtering of the combined phase difference signal data step further includes measuring the amount of jitter present on the first signal in a subband having a frequency range from about 0.1 Hertz to about 1 Kilohertz.
Claim 96
Dependent Claim
44 words
The method of claim 90 in which the filtering of the combined phase difference signal data step further includes measuring the amount of jitter present on the first signal in a wideband having a frequency range from about 10 Hertz to about 5 Megahertz.
Claim 97
Dependent Claim
44 words
The method of claim 90 in which the filtering of the combined phase difference signal data step further includes measuring the amount of jitter present on the first signal in a fullband having a frequency range from about 0.1 Hertz to about 5 Megahertz.
Claim 98
Dependent Claim
43 words
The method of claim 90 in which the filtering of the combined phase difference signal data step further includes measuring the amount of jitter present on the first signal in a highband having a frequency range from about 700 to about 5 Megahertz.
Claim 99
Dependent Claim
78 words
The method of claim 73 in which the processing digitally step further includes at least one of loop filtering the phase difference signal data, integrating the phase difference signal data, low pass filtering the phase difference signal data, high pass filtering the phase difference signal data, detecting in the phase difference signal data an out-of-lock condition, and summing filtered phase difference data amplitudes of the second frequency components over a first time interval for an amount of wander.
Claim 100
Dependent Claim
30 words
The method of claim 96 in which he loop filtering step further includes setting digitally a low pass breakpoint in a range from about 500 Hertz to about 1 Kilohertz.
Claim 101
Dependent Claim
23 words
The method of claim 96 in which the low and high pass filtering step further includes implementing low and high pass filter functions.
Claim 102
Dependent Claim
43 words
The method of claim 98 in which the low and high pass filtering function step further includes measuring the amount of wander present on the first signal in a wander band having a frequency range from about zero Hertz to about 10 Hertz.
Claim 103
Dependent Claim
20 words
The method of claim 99 further including the step of generating a wander measurement output as a function of time.
Claim 104
Dependent Claim
30 words
The method of claim 98 in which the low pass filter function further includes setting digitally a low pass breakpoint in a range from about 10 Hertz to 20 Hertz.
Claim 105
Dependent Claim
31 words
The method of claim 98 in which the high pass filter function further includes setting digitally a high pass breakpoint in a range from about 0.1 Hertz to about 20 Hertz.
Claim 106
Dependent Claim
30 words
The method of claim 102 in which the digitally setting step includes continuously setting the high pass filter function in a range from about 0.1 Hertz to about 20 Hertz.
Claim 107
Dependent Claim
28 words
The method of claim 102 in which the digitally setting step includes setting the high pass filter function in steps from about 0.1 Hertz to about 20 Hertz.
Claim 108
Dependent Claim
55 words
The method of claim 96 further including the step of storing the minimum and maximum peak-to-peak-values of phase difference data amplitudes over a second time interval and summing and executing a RMS function on and filtered phase difference data amplitudes over the second time interval for generating RMS values from the frequency band implementing means.
Claim 109
Dependent Claim
21 words
The method of claim 105 further including the step of generating a jitter measurement output as a function of unit intervals.
Claim 110
Dependent Claim
39 words
The method of claim 96 further including the step of filtering digitally at predetermined low and high pass breakpoints the combined phase difference signal data to measure at least one of the amount of jitter on the first signal.
Claim 111
Dependent Claim
44 words
The method of claim 107 in which the filtering of the combined phase difference signal data step further includes measuring the amount of jitter present on the first signal in a subband having a frequency range from about 0.1 Hertz to about 1 Kilohertz.
Claim 112
Dependent Claim
44 words
The method of claim 107 in which the filtering of the combined phase difference signal data step further includes measuring the amount of jitter present on the first signal in a wideband having a frequency range from about 10 Hertz to about 5 Megahertz.
Claim 113
Dependent Claim
44 words
The method of claim 107 in which the filtering of the combined phase difference signal data step further includes measuring the amount of jitter present on the first signal in a fullband having a frequency range from about 0.1 Hertz to about 5 Megahertz.
Claim 114
Dependent Claim
43 words
The method of claim 107 in which the filtering of the combined phase difference signal data step further includes measuring the amount of jitter present on the first signal in a highband having a frequency range from about 700 to about 5 Megahertz.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2001-05-18 | 2001-11-17 | 2002-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-18 | 2005-11-17 | 2006-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-18 | 2009-11-17 | 2010-05-19 | $7700.00 | Window Closed / Lapsed |