129 results about "Cable tester" patented technology

A cable tester includes a pretest module that senses activity on a cable and selectively enables testing depending upon the sensed activity. A test module is enabled by the pretest module, transmits test pulses on the cable, measures a refelction amplitude, calculates a cable length, and determines a cable status based on the measures amplitude and the calculated cable length. A polarity detector communicates with the cable tester and detects a polarity of at least one pair of the cable. The test module senses activity on a first pair of the cable, enables testing if activity is not detected for a first period, and enables testing of the first pair if, during the first period, activity is detected on the first pair and is subsequently not detected on the first pair for a second period after the activity is detected.

A cable tester tests cable to determine a cable status. The cable status includes an open status, a normal status and a short status. A pretest module senses activity on the cable and selectively enables testing based on said sensed activity. A test module is enabled by the pretest module, transmits a test pulse on the cable, measures a reflection amplitude and calculates a cable length. The test module determines the cable status based on the measured amplitude and the calculated cable length.

A physical layer device according to some implementations includes a cable tester that generates a test pulse on a cable and that determines a cable status including an open status, a short status, and a normal status. A cable impedance estimator communicates with the cable tester and estimates an impedance of the cable based on a reflection amplitude of the test pulse.

A physical layer device includes first, second, third and fourth twisted pairs. First, second, third and fourth hybrid devices communicate with the first, second, third and fourth twisted pairs, respectively. First, second, third and fourth cable testers communicate with the first, second, third and fourth hybrid devices, respectively. Each of the cable testers tests the first, second, third and fourth twisted pairs and determines a cable status of the first, second, third and fourth twisted pairs during first, second, third and fourth periods, respectively. At least one of the first, second, third and fourth periods overlaps another of the first, second, third and fourth periods.A cable testing system and method tests cable and determines status, cable length and reflection amplitude. The test module includes a pretest state machine that senses activity on the cable and enables testing if activity is not detected for a first period. A test state machine is enabled by the pretest state machine, transmits a test pulse on the cable, measures a reflection amplitude and calculates a cable length. The test module determines the status based on the measured amplitude and the calculated cable length. A lookup table includes a plurality of sets of reflection amplitudes as a function of cable length. The test module determines the status using the lookup table, the reflection amplitude and the cable length.