Dynamic receiver
A receiver is presented, such that the receiver may be configured to receive transmissions in accordance with a continuous waveform and to relock quickly on a received transmission when the transmitter is switched or a change in the waveform parameters is made. The receiver may be configured to support reception of a shared channel and/or of a channel allocated for SCPC usage and may be modified while used (e.g., dynamic SCPC). In addition, a satellite communication system is presented, the satellite communication system comprising at least one receiver in accordance with the above-described receiver. The satellite communication system may be configured to utilize the receiver's characteristics for at least the purpose of achieving a highly efficient return link channel.
1. A receiver, comprising:
a demodulator configured to receive a first transmission comprising a sequence of frames, and to lock on a second transmission in response to receiving a relock signal, wherein the first transmission is received over a return link channel from a first terminal and the second transmission is received over the return link channel from a second terminal;
a storage configured to store a plurality of channel profiles and to transfer any of the plurality of channel profiles to the demodulator in response to receiving a load profile signal; and
a controller configured to provide the load profile signal to the storage and provide, responsive to receiving a trigger, the relock signal to the demodulator.
2. The receiver of claim 1 , wherein the demodulator is configured to lock on the second transmission without losing any frame of the sequence of frames.
3. The receiver of claim 1 , wherein the demodulator is configured to lock on the second transmission in accordance with a last channel profile provided to the demodulator.
4. The receiver of claim 1 , wherein the demodulator is configured to:
prior to locking on the second transmission, extract an in-band signal from the first transmission, wherein the in-band signal comprises a number of additional frames to be received before the demodulator relocks.
5. The receiver of claim 1 , wherein each of the plurality of channel profiles comprises a symbol rate attribute or a frequency attribute.
6. The receiver of claim 1 , wherein the storage is further configured to, responsive to receiving the load profile signal:
transfer a next channel profile to the demodulator; and
switch roles between a current channel profile and the next channel profile.
7. The receiver of claim 1 , wherein the trigger comprises one of an external trigger or an in-band trigger, and wherein the controller is further configured to:
receive, from a source external to the receiver, the external trigger at a time prior to a time the receiver locks on the second transmission; and
receive, from the demodulator, the in-band trigger in response to receiving a specified number of additional frames.
8. The receiver of claim 1 , wherein the first transmission is in accordance with a Digital Video Broadcasting-Satellite-Second Generation (DVB-S2) waveform or a Digital Video Broadcasting-Satellite-Second Generation Extensions (DVB-S2X) waveform.
9. A satellite communication system comprising a plurality of terminals and a hub, wherein the hub comprises:
a shared medium manager configured to assign a return link (RL) channel to multiple terminals of the plurality of terminals; and
a receiver configured to receive a transmission over the RL channel, wherein the receiver comprises:
a demodulator configured to receive the transmission comprising a sequence of frames, and to relock on the transmission in response to receiving a relock signal to relock on the transmission;
a storage configured to store a plurality of channel profiles and to transfer any of the plurality of channel profiles to the demodulator in response to receiving a load profile signal; and
a controller configured to provide the load profile signal to the storage and provide, responsive to receiving a trigger, the relock signal to the demodulator.
10. The satellite communication system of claim 9 , wherein the shared medium manager is configured to assign the RL channel to the multiple terminals in turns by:
determining, for each terminal of the multiple terminals a number of consecutive frames the terminal is allowed to transmit in a single transmission;
determining, in accordance with the determined number of consecutive frames for each terminal of the multiple terminals, transmission periods for the multiple terminals to transmit data over the RL channel;
assigning, to each of the multiple terminals, one of the transmission periods; and
setting, using a single channel profile, the receiver to receive transmissions over the RL channel.
11. The satellite communication system of claim 9 , wherein the hub and the multiple terminals are synchronized so that transmissions from different terminals of the multiple terminals do not overlap at an input of the receiver.
12. The satellite communication system of claim 11 , wherein the synchronization comprises accounting for times it takes data to travel over a shared medium from each of the multiple terminals to the receiver.
13. The satellite communication system of claim 9 , wherein:
the receiver is triggered to relock whenever a first transmission of one terminal of the multiple terminals ends and a second transmission of another terminal of the multiple terminals starts; and
the receiver is configured to relock on the second transmission without losing any frame of the first transmission and any frame of the second transmission.
14. The satellite communication system of claim 9 , further comprising a synchronization element coupled to the shared medium manager and to the receiver and configured to provide triggers to the receiver in accordance with transmission periods determined by the shared medium manager and assigned to the multiple terminals.
15. The satellite communication system of claim 9 , wherein the transmission is in accordance with a Digital Video Broadcasting-Satellite-Second-Second Generation (DVB-S2) waveform or A Digital Video Broadcasting-Satellite-Second Generate Extensions (DVB-S2X) waveform.
16. The satellite communication system of claim 9 , wherein the shared medium manager is configured to modify the RL channel while the RL channel is assigned to a terminal of the plurality of terminals.
17. The satellite communication system of claim 16 , wherein modification of the RL channel comprises:
determining a time for modifying a frequency attribute of the RL channel or a bandwidth of the RL channel;
storing, in the storage, a next channel profile corresponding to a modified frequency attribute or modified bandwidth; and
sending, to the terminal, a notification comprising the modified frequency attribute or the modified bandwidth and a time corresponding to the determined time for modifying the RL channel.
18. The satellite communication system of claim 17 , wherein the modification of the RL channel further comprises:
triggering the receiver to load the next channel profile to its demodulator; and
triggering the receiver to relock on a next transmission in accordance with the next channel profile at about the determined time.
19. A method, comprising:
receiving, by a demodulator of a receiver, a first transmission over a return link channel from a first terminal;
storing, by a storage of the receiver, a plurality of channel profiles;
providing, by a controller of the receiver, a load profile signal to the storage;
responsive to receiving a trigger, providing, by the controller of the receiver, a relock signal to the demodulator;
transferring, by the storage, a channel profile of the plurality of channel profiles to the demodulator in response to receiving the load profile signal; and
locking, by the demodulator in response to the relock signal, on a second transmission that is received over the return link channel from a second terminal.
20. The method of claim 19 , further comprising:
extracting the trigger from the first transmission.