Testing of CATV systems
First Claim
1. A method for determining a transit time to a feature in a digital communication circuit comprising (a) generating data that is at least quasi-random, (b) transmitting the at least quasi-random data along the digital communication circuit from a transmitting end of the digital communication circuit, (c) recovering reflections from the digital communication circuit adjacent the transmitting end of the digital communication circuit, (d) correlating the reflections with the data to generate a correlation result, (e) identifying a reflection peak in the correlation result, and (f) determining a time delay to the reflection peak.
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Accused Products
Abstract
A method and apparatus for determining the location of an impedance mismatch in a digital communication circuit (22) generate (20) at least quasi-random data, transmit the data along the circuit (22) from a transmitting end of the circuit (22), recover (24) reflections from impedance mismatches in the circuit (22) adjacent the transmitting end of the circuit (22), correlate the reflections with the data to generate a correlation result, identify a reflection peak in the result, and multiply the propagation velocity of the data through the circuit (22) by a time delay to the reflection peak.
65 Citations
22 Claims
- 1. A method for determining a transit time to a feature in a digital communication circuit comprising (a) generating data that is at least quasi-random, (b) transmitting the at least quasi-random data along the digital communication circuit from a transmitting end of the digital communication circuit, (c) recovering reflections from the digital communication circuit adjacent the transmitting end of the digital communication circuit, (d) correlating the reflections with the data to generate a correlation result, (e) identifying a reflection peak in the correlation result, and (f) determining a time delay to the reflection peak.
- 12. Apparatus for determining a transit time to a feature in a digital communication circuit comprising a first device for generating data that is at least quasi-random, a second device for coupling the first device to the digital communication circuit to transmit the at least quasi-random data along the digital communication circuit from a transmitting end of the digital communication circuit, a third device for recovering reflections from the digital communication circuit, the third device coupled to the digital communication circuit adjacent the transmitting end of the digital communication circuit, and a fourth device for correlating the reflections with the data to generate a correlation result, for identifying a reflection peak in the correlation result, and for determining a time delay to the reflection peak.
Specification