Signal synchronization and payload extraction in a communication network or other network
A method includes obtaining, at a specified device, one or more bandwidth maps contained in communications in a first direction along a transmission medium. Each bandwidth map identifies when one or more other devices are allowed to communicate in a second direction opposite the first direction along the transmission medium. The method also includes using the one or more bandwidth maps to identify expected features of communications from the one or more other devices in the second direction along the transmission medium. The method further includes identifying actual features of the communications from the one or more other devices in the second direction along the transmission medium. In addition, the method includes synchronizing the specified device with the communications from the one or more other devices using the expected and actual features.
1 . A method comprising:
obtaining, at a specified device, one or more bandwidth maps contained in communications in a first direction along a transmission medium, each bandwidth map identifying when one or more other devices are allowed to communicate in a second direction opposite the first direction along the transmission medium;
using the one or more bandwidth maps to identify expected features of communications from the one or more other devices in the second direction along the transmission medium;
identifying actual features of the communications from the one or more other devices in the second direction along the transmission medium;
synchronizing the specified device with the communications from the one or more other devices using the expected and actual features; and
labeling bits associated with the communications from the one or more other devices with tags identifying correct features.
2 . The method of claim 1 , wherein synchronizing the specified device with the communications from the one or more other devices comprises:
comparing the expected features to a collection of the actual features;
in response to determining that at least some of the expected and actual features do not match, shifting the collection of the actual features; and
comparing the expected features to the shifted collection of the actual features.
3 . The method of claim 1 , wherein:
each bandwidth map is associated with a frame in the first direction and identifies (i) at least one of the one or more other devices allowed to communicate in a corresponding frame in the second direction and (ii) at least one time slot in which the at least one of the one or more other devices is allowed to communicate in the corresponding frame; and
at least some of the expected features are based on the at least one time slot from the one or more bandwidth maps.
4 . The method of claim 1 , wherein labeling the bits comprises generating the tags identifying the correct features after the actual features are aligned with the expected features.
5 . The method of claim 1 , further comprising:
performing payload extraction of data contained in the communications from the one or more other devices.
6 . The method of claim 1 , wherein synchronizing the specified device with the communications from the one or more other devices comprises:
synchronizing the specified device with the communications from the one or more other devices without using range information from the specified device to the one or more other devices.
7 . The method of claim 1 , wherein:
the transmission medium comprises at least one optical fiber;
the one or more other devices comprise one or more optical network units configured to communicate with an optical line terminal over the at least one optical fiber;
the first direction is associated with transmissions from the optical line terminal to the one or more optical network units; and
the second direction is associated with transmissions from the one or more optical network units to the optical line terminal.
8 . An apparatus comprising:
at least one interface configured to be coupled to a transmission medium; and
at least one processing device configured to:
obtain one or more bandwidth maps contained in communications in a first direction along the transmission medium, each bandwidth map identifying when one or more other devices are allowed to communicate in a second direction opposite the first direction along the transmission medium;
use the one or more bandwidth maps to identify expected features of communications from the one or more other devices in the second direction along the transmission medium;
identify actual features of the communications from the one or more other devices in the second direction along the transmission medium; and
synchronize with the communications from the one or more other devices using the expected and actual features;
wherein, to synchronize with the communications from the one or more other devices, the at least one processing device is configured to:
compare the expected features to a collection of the actual features;
in response to determining that at least some of the expected and actual features do not match, shift the collection of the actual features; and
compare the expected features to the shifted collection of the actual features.
9 . The apparatus of claim 8 , wherein the at least one processing device is configured to repeatedly compare the expected features to the collection of the actual features, shift the collection of the actual features, and compare the expected features to the shifted collection of the actual features until the actual features align with the expected features.
10 . The apparatus of claim 8 , wherein:
each bandwidth map is associated with a frame in the first direction and identifies (i) at least one of the one or more other devices allowed to communicate in a corresponding frame in the second direction and (ii) at least one time slot in which the at least one of the one or more other devices is allowed to communicate in the corresponding frame; and
at least some of the expected features are based on the at least one time slot from the one or more bandwidth maps.
11 . The apparatus of claim 8 , wherein the at least one processing device is further configured to label bits associated with the communications from the one or more other devices with tags identifying correct features.
12 . The apparatus of claim 8 , wherein the at least one processing device is further configured to perform payload extraction of data contained in the communications from the one or more other devices.
13 . The apparatus of claim 8 , wherein the at least one processing device is configured to synchronize with the communications from the one or more other devices without using range information from the apparatus to the one or more other devices.
14 . The apparatus of claim 8 , wherein:
the transmission medium comprises at least one optical fiber;
the one or more other devices comprise one or more optical network units configured to communicate with an optical line terminal over the at least one optical fiber;
the first direction is associated with transmissions from the optical line terminal to the one or more optical network units; and
the second direction is associated with transmissions from the one or more optical network units to the optical line terminal.
15 . A non-transitory machine readable medium containing instructions that when executed cause at least one processor to:
obtain one or more bandwidth maps contained in communications in a first direction along a transmission medium, each bandwidth map identifying when one or more other devices are allowed to communicate in a second direction opposite the first direction along the transmission medium;
use the one or more bandwidth maps to identify expected features of communications from the one or more other devices in the second direction along the transmission medium;
identify actual features of the communications from the one or more other devices in the second direction along the transmission medium; and
synchronize with the communications from the one or more other devices using the expected and actual features;
wherein the instructions that when executed cause the at least one processor to synchronize with the communications from the one or more other devices comprise instructions that when executed cause the at least one processor to:
compare the expected features to a collection of the actual features;
in response to determining that at least some of the expected and actual features do not match, shift the collection of the actual features; and
compare the expected features to the shifted collection of the actual features.
16 . The non-transitory machine readable medium of claim 15 , wherein the instructions when executed cause the at least one processor to compare the expected features to the collection of the actual features, shift the collection of the actual features, and compare the expected features to the shifted collection of the actual features until the actual features align with the expected features.
17 . The non-transitory machine readable medium of claim 15 , wherein:
each bandwidth map is associated with a frame in the first direction and identifies (i) at least one of the one or more other devices allowed to communicate in a corresponding frame in the second direction and (ii) at least one time slot in which the at least one of the one or more other devices is allowed to communicate in the corresponding frame; and
at least some of the expected features are based on the at least one time slot from the one or more bandwidth maps.
18 . The non-transitory machine readable medium of claim 15 , further containing instructions that when executed cause the at least one processor to at least one of:
label bits associated with the communications from the one or more other devices with tags identifying correct features; and
perform payload extraction of data contained in the communications from the one or more other devices.
19 . The non-transitory machine readable medium of claim 15 , wherein the instructions when executed cause the at least one processor to synchronize with the communications from the one or more other devices without using range information to the one or more other devices.
20 . The non-transitory machine readable medium of claim 15 , wherein:
the transmission medium comprises at least one optical fiber;
the one or more other devices comprise one or more optical network units configured to communicate with an optical line terminal over the at least one optical fiber;
the first direction is associated with transmissions from the optical line terminal to the one or more optical network units; and
the second direction is associated with transmissions from the one or more optical network units to the optical line terminal.