Integrated adjustable short-haul/long-haul time domain reflectometry
First Claim
1. A method for performing integrated adjustable short-haul/long-haul time domain reflectometry, the method comprising:
- setting a time domain reflectometry (TDR) pulse count to a predetermined number;
transmitting a TDR pulse, the width of the TDR pulse being a function of the multiplication of the TDR pulse count with the period of a TDR clock;
detecting whether the TDR pulse has been reflected; and
if the TDR pulse has not been reflected, successively increasing the TDR pulse count to successively increase the width of the transmitted TDR pulse until a reflection is detected.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and system for performing integrated adjustable short-haul/long-haul time domain reflectometry (TDR). A TDR pulse count is set to a predetermined number. Next, a TDR pulse is transmitted through a cable. The width of the TDR pulse is a function of the multiplication of the TDR pulse count with the period of a TDR clock. It is then determined whether the TDR pulse has been reflected back. If the TDR pulse has not been reflected, the TDR pulse count is successively increased to successively increase the width of the transmitted TDR pulse until a reflection is detected—indicating an open in the cable. Furthermore, it eliminates false detections of cable opens. Moreover, the system can be combined into a line interface unit (LIU) integrated circuit such that TDR functionality can be performed automatically without the use of a technician.
14 Citations
44 Claims
-
1. A method for performing integrated adjustable short-haul/long-haul time domain reflectometry, the method comprising:
-
setting a time domain reflectometry (TDR) pulse count to a predetermined number;
transmitting a TDR pulse, the width of the TDR pulse being a function of the multiplication of the TDR pulse count with the period of a TDR clock;
detecting whether the TDR pulse has been reflected; and
if the TDR pulse has not been reflected, successively increasing the TDR pulse count to successively increase the width of the transmitted TDR pulse until a reflection is detected. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A Line Interface Unit (LIU) integrated circuit comprising:
time domain reflectometry (TDR) control logic including;
a TDR pulse generator coupled to a TDR clock, the TDR pulse generator to generate a TDR pulse which is then transmitted through a cable, the width of the TDR pulse being a function of the multiplication of a TDR pulse count with the period of the TDR clock; and
a TDR processor coupled to the TDR pulse generator and a reflection detector, the reflection detector to detect whether the TDR pulse has been reflected;
wherein, if a reflection is not detected, the TDR processor to successively increase the TDR pulse count to successively increase the width of the transmitted TDR pulse generated by the TDR pulse generator until a reflection is detected. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
-
23. A system for performing integrated adjustable short-haul/long-haul time domain reflectometry, the system comprising:
-
an access device coupling a first network to a second network, the access device having at least one line card including at least one Line Interface Unit (LIU) integrated circuit that includes;
time domain reflectometry (TDR) control logic comprising;
a TDR pulse generator coupled to a TDR clock, the TDR pulse generator to generate a TDR pulse which is then transmitted through a cable, the width of the TDR pulse being a function of the multiplication of a TDR pulse count with the period of the TDR clock; and
a TDR processor coupled to the TDR pulse generator and a reflection detector, the reflection detector to detect whether the TDR pulse has been reflected;
wherein, if a reflection is not detected, the TDR processor to successively increase the TDR pulse count to successively increase the width of the transmitted TDR pulse generated by the TDR pulse generator until a reflection is detected. - View Dependent Claims (24, 25, 26, 27, 28, 29, 30, 31, 32, 33)
-
-
34. A machine-readable medium having stored thereon instructions, which when executed by a Line Interface Unit (LIU) integrated circuit, cause the LIU integrated circuit to perform the following operations:
-
setting a time domain reflectometry (TDR) pulse count to a predetermined number;
transmitting a TDR pulse, the width of the TDR pulse being a function of the multiplication of the TDR pulse count with the period of a TDR clock;
detecting whether the TDR pulse has been reflected; and
if the TDR pulse has not been reflected, successively increasing the TDR pulse count to successively increase the width of the transmitted TDR pulse until a reflection is detected. - View Dependent Claims (35, 36, 37, 38, 39, 40, 41, 42, 43, 44)
-
Specification