Variable modulation unicast system
View Patent ↗A system is described that consists of a variable modulation unicast system that utilizes multiple modulation schemes in a cable network for unicast applications and is capable of assigning users to different channels of differing modulation schemes in the network based on a feedback signal received in response to a transmitted probe signal. The system may also, in response to the feedback signal from a remote device in the network, assign a channel from a plurality of channels having differing carrier frequencies and modulation schemes to the remote device and may also modify the carrier frequencies of the channels.
1. A method for a selecting a channel from a plurality of channels for assignment to a remote device in a variable modulation unicast system, the method comprising:
transmitting a plurality of first signals to a plurality of remote devices over a plurality of channel-paths to the plurality of remote devices, wherein each first signal utilizes a first modulation scheme;
receiving a plurality of feedback signals from the plurality of remote devices in response to transmitting the first signals, wherein each feedback signal includes identification information for a corresponding remote device of the plurality of remote devices and a first metric value representative of the transmission characteristics of the channel-path to the corresponding remote device;
assigning a first assigned-channel having an assigned-channel carrier frequency from the plurality of channels to the corresponding remote device in response to the received first metric signal from the corresponding remote device, wherein assigning the first assigned-channel to the corresponding remote device further includes:
determining the availability of a subplurality of channels from the plurality of channels in response to the statistical information, wherein the availability of the channel is determined in response to the first metric values and identification information related to the corresponding remote devices previously assigned to the subplurality of channels;
determining a modular scheme compatible with each of the subplurality of channels and the corresponding remote device; and
selecting a channel from the subplurality of channels; and
transmitting a second signal to the corresponding remote device, wherein the second signal includes information identifying the first assigned-channel determined in response to the received first metric signal.
2. The method of claim 1 , further including:
storing the first metric value, identification information and first assigned-channel assigned to the corresponding remote device in a storage unit; and
determining statistical information from the first metric values, identification information and first assigned-channels related to each of the corresponding remote devices.
3. The method of claim 2 , wherein the storage unit includes a memory unit.
4. The method of claim 3 , wherein the storage unit includes a database.
5. The method of claim 1 , further including modifying the carrier frequency of the first assigned-channel in response to the statistical information determined from the first metric values, identification information and assigned-channels related to the corresponding remote devices.
6. The method of claim 1 , wherein the first metric value is determined at the corresponding remote device in response to determining the transmission characteristics of the channel-path at the corresponding remote device.
7. The method of claim 6 , wherein the first metric value representative of the transmission characteristics of the channel-path at the corresponding remote device is determined by the corresponding remote device.
8. The method of claim 1 , wherein transmitting a first signal further includes transmitting the first signal over a known-channel utilizing a known-channel carrier frequency.
9. The method of claim 8 , wherein the feedback signal is received on a control-channel utilizing a control-channel frequency.
10. The method of claim 9 , wherein the first metric value represents the SNR, the BER, the PER, or the power level of the received first signal at the corresponding remote device.
11. The method of claim 10 , wherein the corresponding remote device is a cable modem.
12. The method of claim 11 , wherein the cable modem utilizes a Data Over Cable Service Interface Specifications (“DOCSIS”) protocol.
13. The method of claim 11 , wherein the control-channel utilizes the DOCSIS protocol.
14. The method of claim 10 , wherein the corresponding remote device is a Set-Top Box (“STB”) capable of receiving Video-on-Demand (“VOD”) signals.
15. The method of claim 14 , wherein the control-channel utilizes the STB out-of-band (OOB) channel
16. The method of claim 10 , wherein the at least one remote device is a Set-Top Box (“STB”) capable of receiving VOD signals.
17. The method of claim 8 , wherein the identification information includes the Internet Protocol (“IP”) address associated with the corresponding remote device.
18. The method of claim 17 , wherein transmitting the second signal to the corresponding remote device utilizing the first assigned-channel further includes transmitting all VOD signals and all DOCSIS signals.