Adaptive use of satellite uplink bands

• US 8,315,199 B2
• Filed: 03/18/2009
• Issued: 11/20/2012
• Est. Priority Date: 09/26/2006
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Dankberg, Mark D., Miller, Mark J., Jaska, Kristi, Wilson, Robert
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Mohebbi, Kouroush
• Application Number:
  US12/406,861
• Publication Number:
  US 20090290530A1
• Time in Patent Office: 1,343 Days
• Field of Search: None
• US Class Current: 370/316
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18543 for adaptation of transmission parameters, e.g. power control for detecting or preventing errors in the information received H04L1/00
• CPC Class Codes: H04B 7/18582 Arrangements for data linking, i.e. for data framing, for error recovery, for multiple access

Abstract

A method is presented for transmitting data in a satellite system having multiple spot beams comprising (1) sending a broadband signal in a forward direction from a gateway terminal to a communications satellite for relay to at least one subscriber terminal, (2) receiving the broadband signal at the communications satellite, wherein the communications satellite comprises a bent pipe repeater having a plurality of satellite-based transmission amplifiers, (3) using one of the plurality of satellite-based transmission amplifiers to amplify the broadband signal and no other broadband signal from the gateway terminal, to produce an amplified broadband signal, (4) sending the amplified broadband signal as one of a plurality of service spot beams to the at least one subscriber terminal, and (5) receiving and retrieving data from the amplified broadband signal at the at least one subscriber terminal.

Claims

1. A method at a first user terminal in a satellite system, the satellite system including the first user terminal and a second user terminal that are secondary spectrum license holders, the method comprising:

receiving an assignment of a first transmit frequency channel;

transmitting satellite uplink signals during time-separated periods of transmission in the first assigned transmit frequency channel;

monitoring the first assigned transmit frequency channel between the time-separated periods of transmission of satellite uplink signals using a first antenna, the monitoring to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel;

monitoring a second assigned transmit frequency channel different from the first assigned transmit frequency channel using a second antenna, the monitoring to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel, wherein the second assigned transmit frequency channel is assigned to the second user terminal;

generating a first observation result indicating the determination of presence of an interfering terrestrial signal in the first assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel;

receiving an indication of a re-assignment from the first assigned transmit frequency channel to the second assigned transmit frequency channel in response to the first observation result and a second observation result generated by the second user terminal, the second observation result indicating the determination, by the second user terminal, of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel and indicating the determination, by the second user terminal, of lack of a presence of an interfering terrestrial signal in the first assigned transmit frequency channel; and

transmitting second satellite uplink signals in the second assigned transmit frequency channel.

2. A method for allocating transmission bandwidth in a satellite system, the method comprising:

assigning a first transmit frequency channel to a first user terminal that is a secondary spectrum license holder;

assigning a second transmit frequency channel to a second user terminal that is a secondary spectrum license holder, the second transmit frequency channel different from the first assigned transmit frequency channel;

at the first user terminal, transmitting satellite uplink signals during time-separated periods of transmission in the first assigned transmit frequency channel, monitoring the first assigned transmit frequency channel between the time-separated periods of transmission of satellite uplink signals from the first user terminal using a first antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel, monitoring the second assigned transmit frequency channel using a second antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel, generating a first observation result indicating the determination of presence of an interfering terrestrial signal in the first assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel, and reporting the first observation result to a remote processor;

at the second user terminal, transmitting satellite uplink signals during time-separated periods of transmission in the second assigned transmit frequency channel, monitoring the second assigned transmit frequency channel between the time-separated periods of transmission of satellite uplink signals from the second user terminal using a first antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel, monitoring the first assigned transmit frequency channel using a second antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel, generating a second observation result indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the first assigned transmit frequency channel, and reporting the second observation result to the remote processor;

at the remote processor, re-assigning the first user terminal from the first assigned transmit frequency channel to the second assigned transmit frequency channel in response to the first and second observation results reported by the first and second user terminals, respectively, and causing to be transmitted a first message conveying an indication of the second assigned transmit frequency to the first user terminal;

at the remote processor, re-assigning the second user terminal from the second assigned transmit frequency channel to the first assigned transmit frequency channel in response to the first and second observation results reported by the first and second user terminals, respectively, and causing to be transmitted a second message conveying an indication of the first assigned transmit frequency to the second user terminal;

at the first user terminal, in response to the first message conveying the re-assignment, transmitting second satellite uplink signals in the second assigned transmit frequency channel; and

at the second user terminal, in response to the second message conveying the re-assignment, transmitting second satellite uplink signals in the first assigned transmit frequency channel.

3. The method of claim 2 wherein the second assigned transmit frequency channel comprises a neighboring frequency channel adjacent to the first assigned transmit frequency channel.

4. The method of claim 2 wherein the first observation result indicates presence of a Land Mobile Data Services (LMDS) user.

5. The method of claim 2 wherein the first user terminal is further capable of receiving satellite downlink signals in a first assigned receive frequency channel using the second antenna.

6. The method of claim 5 wherein the second antenna is configured for receiving satellite signals, and the first antenna is configured for receiving terrestrial signals.

7. A bandwidth-allocation system for allocating transmission bandwidth in a satellite system, the bandwidth-allocation system comprising:

a first user terminal and a second user terminal that are secondary spectrum license holders;

a remote processor configured to communicate with the first and second user terminals, the remote processor configured to assign the first user terminal to transmit satellite uplink signals in a first assigned transmit frequency channel, and to assign the second user terminal to transmit satellite uplink signals in a second assigned transmit frequency channel different from the first assigned transmit frequency channel;

the first user terminal configured to transmit the satellite uplink signals during time-separated periods of transmission in the first assigned transmit frequency channel, monitor the first assigned transmit frequency channel between the time-separated periods of transmission of satellite uplink signals from the first user terminal using a first antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel, monitor the second assigned transmit frequency channel using a second antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel, generate a first observation result indicating the determination of presence of an interfering terrestrial signal in the first assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel, and report the first observation result to the remote processor;

the second user terminal configured to transmit the satellite uplink signals during time-separated periods of transmission in the second assigned transmit frequency channel, monitor the second assigned transmit frequency channel between the time-separated periods of transmission of satellite uplink signals from the second user terminal using a first antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel, monitor the first assigned transmit frequency channel using a second antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel, generate a second observation result indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the first assigned transmit frequency channel, and report the second observation result to the remote processor;

the remote processor further configured to re-assign the first user terminal from the first assigned transmit frequency channel to the second assigned transmit frequency channel in response to the first and second observation results reported by the first and second user terminals, respectively, and cause to be transmitted a first message conveying an indication of the second assigned transmit frequency to the first user terminal;

the remote processor further configured to re-assign the second user terminal from the second assigned transmit frequency channel to the first assigned transmit frequency channel in response to the first and second observation results reported by the first and second user terminals, respectively, and cause to be transmitted a second message conveying an indication of

the first assigned transmit frequency to the second user terminal;

the first user terminal further configured to transmit second satellite uplink signals in the second assigned transmit frequency channel in response to the first message; and

the second user terminal further configured to transmit second satellite uplink signals in the first assigned transmit frequency channel in response to the second message.

8. The apparatus of claim 7 wherein the second assigned transmit frequency channel comprises a neighboring frequency channel adjacent to the first assigned transmit frequency channel.

9. The apparatus of claim 7 wherein the first observation result indicates presence of a Land Mobile Data Services (LMDS) user.

10. The apparatus of claim 7 wherein the first user terminal is further capable of receiving satellite downlink signals in a first assigned receive frequency channel using the second antenna.

11. The apparatus of claim 10 wherein the second antenna is configured for receiving satellite signals, and the first antenna is configured for receiving terrestrial signals.

12. A first user terminal in a satellite system, the satellite system including the first user terminal and a second user terminal that are secondary spectrum license holders, the first user terminal comprising:

a receiver configured to receive a signal instructing the first user terminal to transmit satellite uplink signals in a first transmit frequency channel;

a transmitter configured to transmit satellite uplink signals during time-separated periods of transmission in the first assigned transmit frequency channel;

a monitor configured to monitor the first assigned transmit frequency channel between the time-separated periods of transmission of satellite uplink signals from the transmitter using a first antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel, to monitor a second assigned transmit frequency channel different from the first assigned transmit frequency channel using a second antenna to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel, the second assigned transmit frequency channel assigned to the second user terminal, and to generate a first observation result indicating the determination of presence of an interfering terrestrial signal in the first assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel;

the transmitter further configured to report an indication of the first observation result;

the receiver further configured to receive a re-assignment message indicating a re-assignment of the first user terminal from the first assigned transmit frequency channel to the second assigned transmit frequency channel in response to the first observation result and a second observation result generated by the second user terminal, the second observation result indicating the determination, by the second user terminal, of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel and indicating the determination, by the second user terminal, of lack of a presence of an interfering terrestrial signal in the first assigned transmit frequency channel; and

the transmitter further configured to transmit second satellite uplink signals in the second assigned transmit frequency channel in response to the re-assignment message.

13. A bandwidth-allocation system for allocating satellite system transmission bandwidth, the bandwidth-allocation system comprising:

transmitting means at a first user terminal for transmitting desired satellite uplink signals during time-separated periods in a first assigned transmit frequency channel in accordance with a first assignment, wherein the first user terminal is a secondary spectrum license holder;

transmitting means at a second user terminal for transmitting desired satellite uplink signals during time-separated periods in a second assigned transmit frequency channel in accordance with a second assignment, the second assigned transmit frequency channel different from the first assigned transmit frequency channel, wherein the second user terminal is a secondary spectrum license holder;

monitoring means at the first user terminal for monitoring the first assigned transmit frequency channel between the time-separated periods using first antenna means to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel, for monitoring the second assigned transmit frequency channel using second antenna means to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel, and for sending a first indication of an observation result indicating the determination of presence of an interfering terrestrial signal in the first assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel;

monitoring means at the second user terminal for monitoring the second assigned transmit frequency channel between the time-separated periods using first antenna means to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel, for monitoring the first assigned transmit frequency channel using second antenna means to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel, and for sending a second indication of an observation result indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the first assigned transmit frequency channel;

assigning means at a remote device for receiving the first and second indications, determining a first re-assignment of the first user terminal from the first assigned transmit frequency channel to the second assigned transmit frequency channel in response to the first and second indications, determining a second re-assignment of the second user terminal from the second assigned transmit frequency channel to the first assigned transmit frequency channel in response to the first and second indications, causing a first message indicating the first re-assignment to be sent to the first user terminal, and causing a second message indicating the second re-assignment to be sent to the second user terminal;

the transmitting means at the first user terminal further for transmitting further desired satellite uplink signals during time-separated periods in the second assigned transmit frequency channel in response to the first message; and

the transmitting means at the second user terminal further for transmitting further desired satellite uplink signals during time-separated periods in the first assigned transmit frequency channel in response to the second message.

14. A method in a satellite system including a first user terminal and a second user terminal that are secondary spectrum license holders, the method comprising:

at the first user terminal;

receiving an assignment of a first transmit frequency channel; and

transmitting satellite uplink signals during time-separated periods of transmission in the first assigned transmit frequency channel;

at the second user terminal;

receiving an assignment of a second transmit frequency channel different from the first assigned transmit frequency channel; and

transmitting satellite uplink signals during time-separated periods of transmission in the second assigned transmit frequency channel;

at the first user terminal;

monitoring the first assigned transmit frequency channel between the time-separated periods of transmission of satellite uplink signals using a first antenna, the monitoring to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel;

monitoring the second assigned transmit frequency channel using a second antenna, the monitoring to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel; and

generating a first observation result indicating the determination of presence of an interfering terrestrial signal in the first assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel;

at the second user terminal;

monitoring the second assigned transmit frequency channel between the time-separated periods of transmission of satellite uplink signals using a first antenna, the monitoring to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the second assigned transmit frequency channel;

monitoring the first assigned transmit frequency channel using a second antenna, the monitoring to determine possible presence of an interfering terrestrial signal that is a primary spectrum license holder in the first assigned transmit frequency channel; and

generating a second observation result indicating the determination of lack of a presence of an interfering terrestrial signal in the second assigned transmit frequency channel and indicating the determination of lack of a presence of an interfering terrestrial signal in the first assigned transmit frequency channel;

at the first user terminal;

receiving an indication of a re-assignment from the first assigned transmit frequency channel to the second assigned transmit frequency channel in response to the first observation result and the second observation result; and

transmitting second satellite uplink signals in the second assigned transmit frequency channel; and

at the second user terminal;

receiving an indication of a re-assignment from the second assigned transmit frequency channel to the first assigned transmit frequency channel in response to the first observation result and the second observation result; and

transmitting second satellite uplink signals in the first assigned transmit frequency channel.