Transceiver self-diagnostics for electromagnetic interference (EMI) degradation in balanced channels
Transceiver self-diagnostics for electromagnetic interference (EMI) degradation in balanced channels. Selective operation of transmitting a common mode signal from a communication link implemented for supporting differential signaling, and appropriate processing of any detected signal energy, such as that corresponding to differential signal energy, provides a measure of electromagnetic compatibility (EMC) corresponding to the communication link. Comparison of detected differential signal energy to one or more thresholds may provide indication of whether or not the communication link is balanced or unbalanced, a degree or margin with which the communication link is compliant in accordance with EMC in accordance with one or more protocols, standards, or recommended practices. Multiple successive measurements of detected differential signal energy may be used to determine a trend of performance, such as whether or not the communication link is trending toward imbalance, failure, or noncompliance.
1. An apparatus comprising:
a common mode circuitry configured to transmit a first common mode signal into an end of a differential communication link for transmission to an other end of the differential communication link; and
a differential mode circuitry configured to detect differential signal energy at the end of the differential communication link when a second common mode signal is transmitted into the other end of the differential communication link and to determine a common mode to differential mode metric based on the detected differential signal energy, wherein the common mode to differential mode metric corresponds to a measure of electromagnetic compatibility (EMC) of the differential communication link.
2. The apparatus of claim 1 , wherein the differential mode circuitry is further configured to:
compare the detected differential signal energy to at least one threshold to determine compliance or noncompliance in accordance with electromagnetic compatibility.
3. The apparatus of claim 1 , wherein the differential mode circuitry is further configured to:
compare the detected differential signal energy to a threshold to determine whether the differential communication link is balanced or unbalanced.
4. The apparatus of claim 1 , wherein the differential mode circuitry is further configured to:
compare the detected differential signal energy to a threshold to determine whether the differential communication link is balanced or unbalanced; and
compare the detected differential signal energy to at least one additional threshold, when the differential communication link is determined as being balanced, to identify a degree of EMC based on at least one protocol, standard, or recommended practice.
5. The apparatus of claim 1 , wherein the differential communication link is a twisted-pair cable.
6. The apparatus of claim 1 , wherein the common mode circuitry is further configured to:
transmit the first common mode signal into the end of the differential communication link when the differential mode circuitry is disabled.
7. The apparatus of claim 1 , wherein:
the common mode circuitry is disabled when the differential mode circuitry is operative; and
the differential mode circuitry is disabled when the common mode circuitry is operative.
8. The apparatus of claim 1 , wherein the apparatus is a communication device that is operative within at least one of a satellite communication system, a wireless communication system, a wired communication system, or a fiber-optic communication system.
9. The apparatus of claim 1 , wherein the apparatus is a first communication device coupled to the end of the differential communication link, and the first common mode signal is transmitted into the other end of the differential communication link by a second communication device coupled to the other end of the differential communication link.
10. An apparatus comprising:
a communication interface configured to receive a common mode signal at an end of a differential communication link, wherein the common mode signal is transmitted via an other end the differential communication link; and
a differential mode circuitry configured to detect differential signal energy at the end of the differential communication link and to determine a common mode to differential mode metric based on the detected differential signal energy, wherein the common mode to differential mode metric corresponds to a measure of electromagnetic compatibility (EMC) of the differential communication link.
11. The apparatus of claim 10 , wherein the differential mode circuitry is further configured to:
compare the detected differential signal energy to at least one threshold to determine compliance or noncompliance with electromagnetic compatibility.
12. The apparatus of claim 10 , wherein the differential mode circuitry is further configured to:
compare the detected differential signal energy to a threshold to determine whether the differential communication link is balanced or unbalanced.
13. The apparatus of claim 10 , wherein the differential mode circuitry is further configured to:
compare the detected differential signal energy to a threshold to determine whether the differential communication link is balanced or unbalanced; and
compare the detected differential signal energy to at least one additional threshold, when the differential communication link is determined as being balanced, to identify a degree of EMC based on at least one protocol, standard, or recommended practice.
14. The apparatus of claim 10 further comprising:
a common mode circuitry configured to transmit an other common mode signal into the differential communication link at the end of the differential communication link for transmission to the other end the differential communication link.
15. The apparatus of claim 10 , wherein the differential communication link is a twisted-pair cable.
16. The apparatus of claim 10 , wherein the apparatus is a communication device that is operative within at least one of a satellite communication system, a wireless communication system, a wired communication system, or a fiber-optic communication system.
17. A method comprising:
operating a common mode circuitry to transmit a first common mode signal into a an end of a differential communication link for transmission to an other end of the differential communication link;
operating a differential mode circuitry to detect differential signal energy at the end of the differential communication link when a second common mode signal is transmitted into the other end of the differential communication link;
determining a common mode to differential mode metric based on the detected differential signal energy; and
determining a measure of electromagnetic compatibility (EMC) of the differential communication link based on the common mode to differential mode metric.
18. The method of claim 17 further comprising:
comparing the detected differential signal energy to at least one threshold for determining compliance or noncompliance based on electromagnetic compatibility; and
comparing the detected differential signal energy to the at least one threshold for determining whether the differential communication link is balanced or unbalanced.
19. The method of claim 17 further comprising:
comparing the detected differential signal energy to a threshold for determining whether the differential communication link is balanced or unbalanced; and
comparing the detected differential signal energy to at least one additional threshold, when the differential communication link is determined as being balanced, for identifying a degree of EMC based on at least one protocol, standard, or recommended practice.
20. The method of claim 17 , wherein the method is performed within a communication device that is operative within at least one of a satellite communication system, a wireless communication system, a wired communication system, or a fiber-optic communication system.