BEAM FOCUSING IN MULTI-BEAM SATELLITE SYSTEMS BY COMBINING SIGNALS FROM MULTIPLE SATELLITE BEAMS ON THE GROUND

• US 20080001812A1
• Filed: 11/02/2006
• Published: 01/03/2008
• Est. Priority Date: 06/30/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Jalali, Ahmad
• Granted Patent: US 8,600,292 B2
• Time in Patent Office: Days
• US Class Current: 342/354
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/2041 Spot beam multiple access

Abstract

A satellite communication system designed to communicate with wireless communication devices (WCDs) by use of a mosaic pattern of signal beams uses multiple beams to augment the communication with individual WCDs. In addition to communication with a WCD through a primary beam for that WCD, adjacent beams are used, but with signals utilizing circuit parameters assigned to the primary beam. The signals from a given WCD are relayed in a backhaul, either as an aggregate signal processed by the satellite, or as backhaul communication signals to be combined or separated on the ground.

Claims

1. In a multi-beam satellite system in which a plurality of beams provide coverage to a geographical region using a pattern of signal beams, a method for enhancing communication coverage comprising:

assigning signals for each of the plurality of beams;

communicating signals, in at least one of an uplink and a downlink, with a plurality of wireless communication devices (WCDs), including communicating with at least one of the WCDs in at least one of the uplink and downlink in a plurality of the beams; and

providing backhaul communication corresponding to the communicated signals in a backhaul transmission through at least one gateway, at least a subset of the backhaul communication corresponding to respective ones of the plurality of beams such that the backhaul communication includes signals corresponding to signals communicated with said one of the WCDs through a primary beam and a secondary beam.

2. The method of claim 1, comprising:

assigning a set of signal parameters for each of the plurality of beams in accordance with a repeating signal parameter pattern; and

providing at least a subset of the backhaul communication corresponding to respective ones of the plurality of beams such that the backhaul communication includes signals corresponding to signals communicated with said one of the WCDs through a primary beam and a secondary beam according to circuit parameters assigned to the primary beam.

3. The method of claim 1, comprising using a frequency reuse pattern to provide the repeating signal parameter pattern, wherein at least two adjacent beams have different frequency assignments.

4. The method of claim 1, comprising using a frequency reuse pattern to provide the repeating signal parameter pattern, wherein at least two adjacent beams have the same frequency assignments.

5. The method of claim 1, comprising:

assigning a set of signal parameters in which the signal parameters for at least one pair of adjacent beams have at least one different signal parameter; and

providing at least a subset of the backhaul communication corresponding to respective ones of the plurality of beams such that the backhaul communication includes signals corresponding to signals communicated with said one of the WCDs through a primary beam and a secondary beam corresponding to signals communicated in said beams.

6. The method of claim 1, comprising:

for said one of the WCDs, determining the primary beam for receiving signals from the WCD and selecting at least one adjacent beam as the secondary beam; and

communicating corresponding signals in a backhaul transmission, at least a portion of said corresponding signals corresponding to respective ones of the plurality of beams used for communicating with said one of the WCDs.

7. The method of claim 1, wherein, in an uplink, a combination of signals received from all beams use a maximal ratio combining (MRC) algorithm, the maximal ratio combining algorithm adding the signals coherently.

8. The method of claim 1, wherein, in an uplink, a combination of signals from all beams use a minimal mean squared error (MMSE) algorithm.

9. The method of claim 1, comprising:

for each of a plurality of users, selecting a primary beam for communicating with the user;

for at least a subset of the plurality of users determining a set of beams comprising the primary beam and at least one beam adjacent the primary beam; and

communicating in at least one of the uplink and downlink with each user in the subset of users by using the set of signal parameters assignment for communicating with the user through the primary beam and the set of beams determined for that user using the signal parameters assignment for communicating with the user through the primary beam.

10. The method of claim 9, comprising communicating, in a backhaul, signals corresponding to each of the beams determined for that user in an aggregate backhaul signal.

11. The method of claim 9, comprising communicating, in a backhaul, a combination of signals corresponding to each of the beams determined for that user, the combination resolved between the sets of beams and that user at the satellite.

12. The method of claim 9, comprising using a frequency reuse pattern to provide a repeating signal parameter pattern, wherein at least two adjacent beams have different frequency assignments.

13. The method of claim 1, retransmitting received uplink signals through the backhaul communication, a portion of the retransmitted signals corresponding to respective ones of the plurality of beams, the retransmission including retransmissions of signals received at signal parameters corresponding to an adjacent beam.

14. The method of claim 1, further comprising nulling at least one interfering transmission by applying a combining algorithm to the signals from a plurality of received beams.

15. The method of claim 1, comprising:

communicating with said one of the WCDs in the plurality of the beams in the return link; and

providing the backhaul communication corresponding to the communicated signals by relaying the signals received from said one of the WCDs in the backhaul.

16. The method of claim 1, comprising:

communicating with said one of the WCDs in the plurality of the beams in the forward link; and

providing the backhaul communication corresponding to the communicated signals by relaying the signals received from the backhaul to said one of the WCDs.

17. The method of claim 1, comprising using a plurality of different signals for communicating with the user along different path lengths, and combining the signals in the communication link.

18. A satellite for communicating with a plurality of wireless communication devices (WCDs) in a multi-beam system in which a plurality of beams provide coverage to a geographical region and using a signal parameter pattern in which at least two adjacent beams have different signal parameters, the satellite comprising:

a circuit assigning a set of signal parameters for each of the plurality of beams in accordance with the signal parameter pattern;

a circuit communicating signals with a plurality of wireless communication devices (WCDs) in accordance with the assigned signal parameters;

a circuit communicating corresponding signals in a backhaul transmission through at least one gateway, a portion of the corresponding signals corresponding to signals communicated via respective ones of the plurality of beams such that the backhaul communication includes signals corresponding to signals communicated with said one of the WCDs through a primary beam and a secondary beam according to circuit parameters assigned to the primary beam.

19. The satellite of claim 18, comprising a maximal ratio combining circuit wherein a combination of signals from all beams use a combining algorithm, selected from a maximal ratio combining (MRC) algorithm and a minimal mean squared error combining (MMSE) algorithm.

20. The satellite of claim 18, wherein:

the circuit for communicating signals with the plurality of WCDs includes a selection circuit which, for each of a plurality of users, selects a primary beam for communicating with the user, and for each of the plurality of users determines a set of beams comprising the primary beam and at least one beam adjacent the primary beam; and

the circuit communicating corresponding signals in a backhaul transmission communicates in at least one of the uplink and downlink with each user by using the set of signal parameters assignment for communicating with the user through the primary beam and the set of beams determined for that user using the signal parameters assignment for communicating with the user through the primary beam.

21. The satellite of claim 20, comprising:

the circuit for assigning a set of signal parameters for each of the plurality of beams providing a repeating signal parameter pattern; and

the circuit communicating signals in the backhaul providing at least a subset of the backhaul communication corresponding to respective ones of the plurality of beams such that the backhaul communication includes signals corresponding to signals communicated with said one of the WCDs through a primary beam and a secondary beam according to circuit parameters assigned to the primary beam.

22. The satellite of claim 20, wherein the circuit for communicating signals with the plurality of WCDs nulls at least one interfering transmission by applying one of a maximal ratio combining (MRC) algorithm to the signals from a plurality of received beams, and a minimum mean squared combining (MMSE) algorithm to the signals from the plurality of received beams.

23. The satellite of claim 18, wherein:

the circuit for communicating with said one of the WCDs communicates in the plurality of the beams in the return link; and

the circuit for communicating corresponding signals in the backhaul communication provides signals corresponding to the communicated signals by relaying the signals received from said one of the WCDs in the backhaul.

24. The satellite of claim 18, comprising:

the circuit for communicating with said one of the WCDs communicates with said one of the WCDs in the plurality of the beams in the forward link; and

the circuit for communicating corresponding signals in the backhaul communication provides the backhaul communication corresponding to the communicated signals by relaying the signals received from the backhaul to said one of the WCDs.

25. A communication device for use in a multi-beam satellite system in which a plurality of beams provide coverage to a geographical region using a signal parameter pattern in which at least two adjacent beams have different signal parameters, the communication device comprising:

means for assigning a set of signal parameters for each of the plurality of beams in accordance with the signal parameter pattern; and

means to process signals in at least one of an uplink and a downlink, communications with a plurality of wireless communication devices (WCDs), the means to process effecting communication with at least one of the WCDs in at least one of the uplink and downlink in a plurality of the beams.

26. The communication device of claim 25, comprising:

means for providing backhaul communication corresponding to the communicated signals in a backhaul transmission through at least one gateway, at least a portion of the backhaul communication corresponding to respective ones of the plurality of beams such that the backhaul communication includes signals corresponding to signals communicated with said one of the WCDs through a primary beam and a secondary beam according to circuit parameters assigned to the primary beam.

27. The communication device of claim 26, comprising:

the means to process signals determining the primary beam for receiving signals from said one of the WCDs and selecting at least one adjacent beam as the secondary beam; and

the means for providing backhaul communication communicating corresponding signals in a backhaul transmission, at least a portion of the backhaul communication corresponding to respective ones of the plurality of beams used for communicating with said one of the WCDs.

28. The communication device of claim 27, wherein the means for providing backhaul communication communicates through a combination of signals corresponding to each of the beams determined for that user, the combination resolved between the sets of beams and that user at the satellite.

29. The communication device of claim 27, wherein the means for providing backhaul communication retransmits received uplink signals, at least a portion of the backhaul communication corresponding to respective ones of the plurality of beams, the retransmission including retransmissions of signals received at signal parameters corresponding to an adjacent beam.

30. The communication device of claim 27, comprising:

the means for assigning a set of signal parameters for each of the plurality of beams providing a repeating signal parameter pattern;

the means for providing backhaul communication providing at least a subset of the backhaul communication corresponding to respective ones of the plurality of beams such that the backhaul communication includes signals corresponding to signals communicated with said one of the WCDs through a primary beam and a secondary beam according to circuit parameters assigned to the primary beam; and

the means to process signals includes wireless communication means which uses a frequency reuse pattern to provide the repeating signal parameter pattern.

31. The communication device of claim 25, wherein the means to process signals includes wireless communication means that uses a plurality of different signals for communicating with the user along different path lengths, and combines the signals in the communication link.

32. A method for using a wireless communication device (WCD) for communicating in a multi-beam satellite system in which a plurality of beams provide coverage to a geographical region using a signal parameter pattern in which at least two adjacent beams have different signal parameters, the comprising:

receiving an assigned set of signal parameters corresponding to at least one of the plurality of beams;

communicating signals, in at least one of an uplink and a downlink, including communicating in at least one of the uplink and downlink in a plurality of the beams.

33. The method of claim 32, comprising processing a combination of signals received from at least two of said beams using a maximal ratio combining (MRC) algorithm.

34. The method of claim 32, comprising processing a combination of signals received from at least two of said beams using a minimal mean squared error combining (MMSE) algorithm.

35. The method of claim 32, further comprising nulling at least one interfering transmission by applying a combining algorithm to the signals from a plurality of received beams.

36. The method of claim 32, comprising using a plurality of different signals for communicating with the user along different path lengths, and combining the signals in the communication link.

37. A method of using a backhaul in a multi-beam satellite system in which a plurality of beams provide coverage to a geographical region using a signal parameter pattern in which at least two adjacent beams have different signal parameters, the method comprising:

providing a backhaul communication corresponding to communications provided for each of at least a subset of the plurality of beams in accordance with the signal parameter pattern;

communicating through the backhaul signals, corresponding to at least one of an uplink and a downlink with a plurality of wireless communication devices (WCDs), wherein the corresponding signals include communications with at least one of the WCDs in at least one of the uplink and downlink in a plurality of the beams; and

providing backhaul communication corresponding to the communicated signals with the plurality of WCDs, at least a subset of the backhaul communication corresponding to respective ones of the plurality of beams with at least one of the WCDs communicating through more than one beam.

38. The method of claim 37, comprising providing the backhaul communication of the signals corresponding to communication in the secondary beam according to circuit parameters assigned to the primary beam.

39. The method of claim 37, comprising:

for said one of the WCDs, determining the primary beam for receiving signals from the WCD and selecting at least one adjacent beam as the secondary beam; and

communicating the corresponding signals in a backhaul transmission, at least a portion of the backhaul communication corresponding to respective ones of the plurality of beams used for communicating with said one of the WCDs.

40. The method of claim 37, wherein, in an uplink, a combination of signals received from all beams use a combining algorithm.

41. The method of claim 37, comprising:

for each of a plurality of users, selecting a primary beam for communicating with the user;

for at least a subset of the plurality of users determining a set of beams comprising the primary beam and at least one beam adjacent the primary beam; and

causing the satellite to communicate in at least one of the uplink and downlink with each user in the subset of users by using the set of signal parameters assignment for communicating with the user through the primary beam and the set of beams determined for that user using the signal parameters assignment for communicating with the user through the primary beam.

42. The method of claim 41, comprising communicating signals corresponding to each of the beams determined for that user.

43. The method of claim 37, retransmitting received uplink signals, at least a portion of the backhaul communication corresponding to respective ones of the plurality of beams, the retransmission including retransmissions of signals received at signal parameters corresponding to an adjacent beam.

44. The method of claim 37, further comprising nulling at least one interfering transmission by applying a combining algorithm to the signals from signals corresponding to a plurality of received beams.

45. The method of claim 37, comprising using a plurality of different signals for communicating with the user along different path lengths, and combining the signals in the communication link.

46. The method of claim 37, comprising:

the plurality of beams having a set of signal parameters assigned in accordance with a repeating signal parameter pattern; and

providing at least a subset of the backhaul communication corresponding to respective ones of the plurality of beams such that the backhaul communication includes signals corresponding to signals communicated with said one of the WCDs through a primary beam and a secondary beam according to circuit parameters assigned to the primary beam.

47. The method of claim 37, wherein the repeating signal parameter pattern uses a frequency reuse pattern.

48. The method of claim 37, wherein the repeating signal parameter pattern uses a frequency reuse pattern in which at least two adjacent beams have the same frequency assignments.

49. A chipset including at least one semiconductor integrated circuit chip, for use in a wireless communication device (WCD), the chipset comprising:

a circuit capable of receiving an assigned set of signal parameters corresponding to at least one of a plurality of beams; and

a circuit capable of effecting communication of signals, in at least one of an uplink and a downlink, including communication in at least one of the uplink and downlink in a plurality of the beams having different signal parameters.

50. The chipset of claim 49, comprising a circuit capable processing a combination of signals received from at least two of said beams using a combining algorithm selected from one of a maximal ratio combining (MRC) algorithm and a minimal mean squared error combining (MMSE) algorithm.

51. The chipset of claim 49, further comprising a circuit capable of nulling at least one interfering transmission by applying a combining algorithm to the signals from a plurality of received beams.

52. The chipset of claim 49, comprising a circuit capable of using a plurality of different signals for communicating with the user along different path lengths, and combining the signals in the communication link.