Overlapping OFDMA channels for coexistence of 3.1 mid-split and high-split cable modems
In some aspects, the disclosure is directed to methods and systems for overlapping orthogonal frequency-division multiple-access (OFDMA) channels for coexistence of devices and legacy devices, including DOCSIS 3.1 mid-split and high-split cable modems (CMs). Described are systems and methods for providing a CMTS with capability for managing overlapping OFDMA channels to support mid-split and high-split CMs, without modification to legacy CMs.
1. A device, comprising:
a transceiver in communication with first one or more devices and second one or more devices, the first one or more devices capable of communication above a first frequency and the second one or more devices incapable of communication above the first frequency; and
circuitry configured to generate and transmit, via the transceiver:
a first communication identifying a first set of channel allocations covering a frequency range from a second frequency lower than the first frequency to a third frequency higher than the first frequency, and
a second communication identifying a second set of channel allocations covering a frequency range from the second frequency to the first frequency; and
wherein the first one or more devices utilize the first set of channel allocations, and the second one or more devices utilize the second set of channel allocations,
wherein a first channel allocation of the first set of channel allocations is associated with a first identifier, and a corresponding second channel allocation of the second set of channel allocations is associated with a second identifier different from the first identifier by an offset value.
2. The device of claim 1 , wherein the second set of channel allocations correspond to a subset of the first set of channel allocations below the first frequency.
3. The device of claim 2 , wherein each channel allocation of the second set of channel allocations is associated with a corresponding channel allocation of the subset of the first set of channel allocations below the first frequency.
4. The device of claim 3 , wherein a first channel allocation of the first set of channel allocations and a corresponding second channel allocation of the second set of channel allocations have identical physical channel parameters.
5. The device of claim 4 , wherein the physical channel parameters of the first channel allocation and the corresponding second channel allocation are each transmitted, by the circuitry of the device via the transceiver, to the first one or more devices and the second one or more devices via an upstream channel descriptor (UCD) message.
6. The device of claim 1 , wherein the circuitry is further configured to:
receive a third communication from a device of the second one or more devices incapable of communication above the first frequency, the third communication associated with the second channel allocation of the second set of channel allocations; and
subtract the offset value from a timestamp in the third communication.
7. The device of claim 1 , wherein the circuitry is further configured to assign a first subchannel to a device of the first one or more devices, the first subchannel having a frequency range above the first frequency; and
wherein the first communication identifies the assignment of the first subchannel, and the second communication does not identify the assignment of the first subchannel.
8. The device of claim 7 , wherein the circuitry is further configured to assign a second subchannel to a device of the first one or more devices, the second subchannel having a frequency range lower than the first frequency; and
wherein the first communication and the second communication identify the assignment of the second subchannel.
9. The device of claim 1 , further comprising circuitry configured to use a single receiver instance to receive transmissions from both the first one or more devices and the second one or more devices.
10. A method, comprising:
generating, by circuitry of a device in communication with a first one or more devices capable of communication above a first frequency and a second one or more devices incapable of communication above the first frequency, a first communication identifying a first set of channel allocations covering a frequency range from a second frequency lower than the first frequency to a third frequency higher than the first frequency;
generating, by the circuitry, a second communication identifying a second set of channel allocations covering a frequency range from the second frequency to the first frequency; and
transmitting, by the circuitry via a transceiver of the device, the first communication and the second communication, receipt of the first communication causing the first one or more devices to utilize the first set of channel allocations and receipt of the second communication causing the second one or more devices to utilize the second set of channel allocations,
wherein a first channel allocation of the first set of channel allocations is associated with a first identifier, and a corresponding second channel allocation of the second set of channel allocations is associated with a second identifier different from the first identifier by an offset value.
11. The method of claim 10 , wherein the second set of channel allocations correspond to a subset of the first set of channel allocations below the first frequency.
12. The method of claim 11 , wherein each channel allocation of the second set of channel allocations is associated with a corresponding channel allocation of the subset of the first set of channel allocations below the first frequency.
13. The method of claim 12 , wherein a first channel allocation of the first set of channel allocations and a corresponding second channel allocation of the second set of channel allocations have identical physical channel parameters.
14. The method of claim 13 , wherein transmitting the first communication and the second communication each comprise transmitting, by the circuitry of the device via the transceiver, an upstream channel descriptor (UCD) message.
15. The method of claim 10 , further comprising:
receiving, by the circuitry via the transceiver, a third communication from a device of the second one or more devices incapable of communication above the first frequency, the third communication associated with the second channel allocation of the second set of channel allocations; and
subtracting, by the circuitry, the offset value from a timestamp in the third communication.
16. The method of claim 10 , further comprising assigning, by the circuitry, a first subchannel to a device of the first one or more devices, the first subchannel having a frequency range above the first frequency; and
wherein the first communication identifies the assignment of the first subchannel, and the second communication does not identify the assignment of the first subchannel.
17. The method of claim 16 , further comprising assigning, by the circuitry, a second subchannel to a device of the first one or more devices, the second subchannel having a frequency range lower than the first frequency; and
wherein the first communication and the second communication identify the assignment of the second subchannel.
18. The method of claim 10 , further comprising receiving, by a single receiver instance of the device, transmissions from both the first one or more devices and the second one or more devices.