Increased capacity communications for OFDM-based wireless communications systems/methods/devices

• US 8,537,916 B2
• Filed: 06/20/2012
• Issued: 09/17/2013
• Est. Priority Date: 03/29/2010
• Status: Active Grant

• Current Assignee: Odyssey Wireless, Inc.
• Original Assignee: Odyssey Wireless, Inc.
• Inventors: Karabinis, Peter D.
• Primary Examiner(s): WANG, TED M
• Application Number:
  US13/528,058
• Publication Number:
  US 20120288023A1
• Time in Patent Office: 454 Days
• Field of Search: 375/260, 375/267, 375/295, 375/299
• US Class Current: 375/260
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 2001/0408 with power amplifiers
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/068 using space frequency diversity space-frequency coding H04L1/0606
• CPC Class Codes: H04B 7/0842 Weighted combining
• CPC Class Codes: H04B 7/0885 with combination
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04B 7/26 at least one of which is mobile
• CPC Class Codes: H04J 11/0036 at the receiver
• CPC Class Codes: H04L 2025/03414 Multicarrier
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 25/03006 Arrangements for removing intersymbol interference
• CPC Class Codes: H04L 25/03343 Arrangements at the transmitter end
• CPC Class Codes: H04L 27/2627 Modulators
• CPC Class Codes: H04L 27/2633 using partial FFTs
• CPC Class Codes: H04L 27/2636 with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/26522 using partial FFTs
• CPC Class Codes: H04L 27/26526 : with inverse FFT [IFFT] or inverse DFT [IDFT] demodulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] receiver or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
• CPC Class Codes: H04L 5/0007 : the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04W 72/046 : the resource being in the space domain, e.g. beams

Abstract

Numerous embodiments are provided that may be used to provide enhanced capacity and/or Quality-of-Service for OFDM-based systems such as LTE and/or WiMAX. Various service/device modes and/or applications are also provided. According to embodiments of the invention, a transformation may be performed on a data vector by a transmitter, prior to the transmitter transmitting the data vector, to distribute elements of the data vector over an available frequency space, thus providing robustness to channel anomalies such as fading and/or interference. Embodiments relating to architectures, systems, methods, devices, software, firmware and/or computer program products are provided.

Claims

1. A communications method comprising:

distributing a data element over a plurality of components/dimensions of a vector;

transmitting the vector by transmitting by a transmitter a plurality of sub-carriers; and

subjecting the vector, prior to said transmitting the vector, to a transformation that depends upon a characteristic of a channel that exists between the transmitter and a receiver;

wherein the transmitter is configured to transmit at least two sub-carriers simultaneously in time therebetween; and

wherein, resulting from said distributing, at least one component/dimension of the vector comprises a superposition of a plurality of data elements.

2. The communications method according to claim 1, wherein said distributing is based upon a Discrete Fourier Transform (DFT) and/or a Fast Fourier Transform (FFT).

3. The communications method according to claim 1, wherein said distributing is based upon a Butler matrix.

4. The communications method according to claim 1, further comprising:

receiving at a receiver the vector responsive to said transmitting the vector;

subjecting the vector that is received at the receiver to a function that is an inverse of said distributing; and

forming an estimate of the data element.

5. The communications method according to claim 4, wherein said receiving at a receiver further comprises:

receiving at an antenna of the receiver that is situated on a tower that is associated with the receiver;

the antenna of the receiver being at a distance from a processor of the receiver;

amplifying, following said receiving, at a location that is proximate to the antenna and is on the tower;

transmitting over a short-range link following said amplifying; and

receiving at the processor of the receiver responsive to said transmitting over the short-range link.

6. The communications method according to claim 5, wherein the antenna of the receiver comprises a two-dimensional lattice of antenna elements.

7. The communications method according to claim 4, further comprising:

estimating at the receiver a state of a communications channel through which said receiving occurs; and

providing data to the transmitter responsive to said estimating at the receiver.

8. The communications method according to claim 1, further comprising:

forming a plurality of vectors by the transmitter for transmission to a respective plurality of receivers; and

sequentially transmitting by the transmitter the plurality of vectors to the respective plurality of receivers;

wherein sequentially transmitting comprises avoiding time overlapping between any two of the respective plurality of vectors that are sequentially transmitted by the transmitter.

9. The communications method according to claim 8, wherein said forming a plurality of vectors by the transmitter for transmission to a respective plurality of receivers comprises:

forming the plurality of vectors and transmitting the plurality of vectors by a plurality of transmitters any two of which are configured to serve geographically distinct service areas.

10. The communications method according to claim 1, further comprising:

receiving the vector at a receiver, responsive to said transmitting the vector, by forming at the receiver a spatial matched filter and/or a spatial rake.

11. The communications method according to claim 10, wherein said forming at the receiver a spatial matched filter and/or a spatial rake comprises:

determining at the receiver a number of signal paths arriving at the receiver; and

forming at the receiver a respective number of antenna lobes, antenna patterns and/or spatial fingers responsive to said determining at the receiver.

12. The communications method according to claim 11, wherein said determining at the receiver a number of signal paths arriving at the receiver comprises:

prior to said determining at the receiver, forming at the receiver an initial number of antenna lobes, antenna patterns and/or spatial fingers; and

processing at the receiver a respective initial number of signals that is provided by the initial number of antenna lobes, antenna patterns and/or spatial fingers that is formed;

wherein the initial number of lobes, antenna patterns and/or spatial fingers that is formed at the receiver is greater than the determined number of signal paths arriving at the receiver.

13. The communications method according to claim 11, further comprising:

combining at the receiver a respective number of signals that is provided by the respective number of antenna lobes, antenna patterns and/or spatial fingers that is formed.

14. The communications method according to claim 12, wherein the initial number of lobes, antenna patterns and/or spatial fingers that is formed at the receiver is formed via a plurality of antenna elements of the receiver;

wherein the plurality of antenna elements of the receiver, comprising a two-dimensional lattice of antenna elements, are arranged vertically and horizontally therebetween over a two-dimensional surface area.

15. The communications method according to claim 1, wherein said superposition comprises a linear superposition.

16. The communications method according to claim 1, wherein each one of a plurality of components/dimensions of the vector comprises a value that is a superposition of a plurality of values of a respective plurality of data elements.

17. The communications method according to claim 1, further comprising:

pseudo-randomly altering at least one element of the vector to thereby provide increased communications security, covertness and/or privacy.

18. The communications method according to claim 1, further comprising:

using by the transmitter a plurality of amplifiers that are configured in accordance with a Butler matrix architecture to amplify the vector prior to said transmitting the vector.

19. The communications method according to claim 1, further comprising:

using by the transmitter a plurality of antennas that are configured to transmit a respective plurality of vectors so as to increase a signal-to-noise and/or a signal-to-interference ratio at a receiver by providing the respective plurality of vectors at an antenna of the receiver substantially coherently therebetween;

wherein each antenna of the plurality of antennas is configured to transmit a weighted replica of the data vector.

20. The communications method according to claim 1, further comprising:

transmitting by the transmitter information to a first device and to a second device sequentially in time, over respective non-overlapping first and second time intervals; and

refraining by the transmitter from transmitting information to the first device and to the second device simultaneously in time.

21. The communications method according to claim 1, further comprising:

distributing the data element over the plurality of components/dimensions of the vector at a processor that is associated with the transmitter and is at a distance from an antenna that is associated with the transmitter;

the antenna that is associated with the transmitter being situated on a tower that is associated with the transmitter;

communicating via a short-range link the vector to a location on the tower that is associated with the transmitter, the location on the tower being proximate to the antenna that is associated with the transmitter;

amplifying the vector following said communicating; and

providing the vector, following said amplifying, to the antenna that is associated with the transmitter.

22. A communications method comprising:

distributing a data element over a plurality of components/dimensions of a vector; and

transmitting the vector by transmitting by a transmitter a plurality of sub-carriers;

wherein the transmitter is configured to transmit at least two sub-carriers simultaneously in time therebetween;

wherein, resulting from said distributing, at least one component/dimension of the vector comprises a superposition of a plurality of data elements; and

wherein transmitting the vector further comprises;

generating a first replica of the vector and a second replica of the vector; and

transmitting by the transmitter the first and second replicas of the vector using respective first and second antenna elements.

23. The communications method according to claim 22, wherein prior to said transmitting by the transmitter the first and second replicas of the vector using respective first and second antenna elements, the method further comprises:

adjusting at least one of the first and second replicas of the vector using at least one channel-dependent weight; and

following said adjusting, transmitting the first replica of the vector using the first antenna element and transmitting the second replica of the vector using the second antenna element, such that said first and second replicas of the vector that are transmitted are received at a receiving antenna coherently therebetween so as to add on a voltage basis therebetween at the receiving antenna.

24. A communications method comprising:

distributing a data element over a plurality of components/dimensions of a vector; and

transmitting the vector by transmitting by a transmitter a plurality of sub-carriers;

wherein the transmitter is configured to transmit at least two sub-carriers simultaneously in time therebetween; and

wherein, resulting from said distributing, at least one component/dimension of the vector comprises a superposition of a plurality of data elements;

transmitting by the transmitter the vector over a plurality of frequency intervals that are non-contiguous therebetween; and

/or

transmitting by the transmitter the vector over a plurality of time intervals that are non-contiguous therebetween.

25. A communications method comprising:

distributing a data element over a plurality of components/dimensions of a vector; and

transmitting the vector by transmitting by a transmitter a plurality of sub-carriers;

wherein the transmitter is configured to transmit at least two sub-carriers simultaneously in time therebetween; and

wherein, resulting from said distributing, at least one component/dimension of the vector comprises a superposition of a plurality of data elements;

amplifying by the transmitter a first subset of the plurality of sub-carriers using a first amplifier; and

amplifying by the transmitter a second subset of the plurality of sub-carriers using a second amplifier;

wherein the first subset of the plurality of sub-carriers differs from the second subset of the plurality of sub-carriers in at least one sub-carrier; and

wherein each one of the first and second subsets of the plurality of sub-carriers comprises at least one sub-carrier of the plurality of sub-carriers.

26. A communications system comprising:

a processor that is configured to distribute a data element over a plurality of components/dimensions of a vector and is further configured to form the vector such that a component/dimension thereof comprises a superposition of a plurality of data elements; and

a transmitter that is configured to transmit the vector by transmitting a plurality of sub-carriers;

wherein the transmitter is configured to transmit at least two sub-carriers simultaneously in time therebetween; and

wherein the processor is further configured to subject the vector to a transformation that depends upon a characteristic of a channel that exists between the transmitter and a receiver.

27. The communications system according to claim 26, wherein the processor is configured to distribute the data element over the plurality of components/dimensions of the vector via a Discrete Fourier Transform (DFT) and/or a Fast Fourier Transform (FFT).

28. The communications system according to claim 26, wherein the processor is configured to distribute the data element over the plurality of components/dimensions of the vector via a Butler matrix.

29. The communications system according to claim 26, further comprising:

a receiver that is configured to receive the vector following transmission thereof by the transmitter;

to perform a function on the received vector that is an inverse of having distributed by the processor the data element over the plurality of the components/dimensions of the vector; and

to form an estimate of the data element.

30. The communications system according to claim 29, wherein the receiver is further configured to estimate a state of a communications channel through which the vector is received at the receiver and to provide data to the transmitter responsive to having estimated said state of the communications channel.

31. The communications system according to claim 29, wherein said receiver is further configured to:

receive a signal at an antenna thereof that is situated at an elevation, on a receiver tower, and is at a distance from a receiver processor;

amplify the signal that is received at the antenna by using an amplifier that is situated proximate to the antenna on the receiver tower;

transmit the amplified signal over a short-range link; and

receive the transmitted amplified signal at the receiver processor.

32. The communications system according to claim 31, wherein the short-range link comprises a wireless short-range link.

33. The communications system according to claim 31, wherein the antenna of the receiver comprises a two-dimensional lattice of antenna elements.

34. The communications system according to claim 26, wherein the processor is further configured to form a plurality of vectors to be transmitted by the transmitter to a respective plurality of receivers;

and wherein the transmitter is configured to transmit the plurality of vectors to the respective plurality of receivers sequentially in time over a respective plurality of time intervals any two of which are devoid of time overlap therebetween.

35. The communications system according to claim 34, wherein the transmitter that is configured to transmit the plurality of vectors comprises a plurality of transmitters any two of which are configured to serve respective first and second geographically distinct service areas.

36. The communications system according to claim 26, further comprising:

a receiver that is configured to receive the vector that is transmitted by the transmitter;

wherein the receiver is configured to receive the vector by using a receiver antenna and a receiver processor that are configured to form a spatial matched filter and/or a spatial rake.

37. The communications system according to claim 36, wherein the receiver antenna and the receiver processor are configured to form the spatial matched filter and/or the spatial rake by being configured to determine a number of signal paths arriving at the receiver, a respective number of signal strengths associated therewith and a respective number of directions-of-arrival associated therewith;

and, responsive to the determined number of signal paths arriving at the receiver, the respective number of signal strengths associated therewith and the respective number of directions-of-arrival associated therewith, to form the spatial matched filter and/or the spatial rake by forming a respective number of antenna lobes, antenna patterns and/or spatial fingers that are combined by the receiver processor in order to maximize a signal-to-noise ratio and/or a signal-to-interference ratio.

38. The communications system according to claim 37, wherein the receiver antenna and the receiver processor are further configured to:

form an initial number of antenna lobes, antenna patterns and/or spatial fingers prior to having determined said number of signal paths arriving at the receiver and prior to having formed said respective number of antenna lobes, antenna patterns and/or spatial fingers;

process a respective initial number of signals that is provided by the initial number of antenna lobes, antenna patterns and/or spatial fingers; and

determine, from the initial number of antenna lobes, antenna patterns and/or spatial fingers and from having processed said respective initial number of signals associated therewith, the number of signal paths arriving at the receiver and the respective number of antenna lobes, antenna patterns and/or spatial fingers to be formed;

wherein the initial number of lobes, antenna patterns and/or spatial fingers that is formed is greater than the number of signal paths arriving at the receiver.

39. The communications system according to claim 37, wherein said respective number of antenna lobes, antenna patterns and/or spatial fingers is formed via a plurality of antenna elements of the receiver antenna comprising a two-dimensional lattice of antenna elements that are arranged vertically and horizontally therebetween over a two-dimensional surface area.

40. The communications system according to claim 26, wherein said component/dimension of the vector comprises a linear superposition of a plurality of values of data elements.

41. The communications system according to claim 26, wherein each one of a plurality of components/dimensions of the vector comprises a value that is a linear superposition of a plurality of values of data elements.

42. The communications system according to claim 26, wherein the transmitter, prior to transmitting the vector, is further configured to pseudo-randomly alter at least one component/dimension thereof to thereby provide increased communications security, covertness and/or privacy.

43. The communications system according to claim 26, wherein the transmitter comprises a plurality of amplifiers that are configured in accordance with a Butler matrix architecture and wherein the transmitter is configured to use the plurality of amplifiers that are configured in accordance with the Butler matrix architecture to amplify the vector.

44. The communications system according to claim 26, wherein the transmitter comprises a plurality of antennas that are configured to transmit a respective plurality of vectors so as to increase a signal-to-noise ratio and/or a signal-to-interference ratio at a receiver by providing the respective plurality of vectors at an antenna of the receiver substantially coherently therebetween;

wherein each antenna of the plurality of antennas is configured to transmit a replica of the vector.

45. The communications system according to claim 26, wherein the transmitter is further configured to transmit information to a first device and to a second device, sequentially in time therebetween, over respective non-overlapping therebetween first and second time intervals, and is also configured to refrain from transmitting information to the first device and to the second device simultaneously in time therebetween.

46. The communications system according to claim 26, wherein said transmitter and/or processor is/are further configured to:

communicate via a short-range link the vector from the processor to a location that is on a tower that is associated with the transmitter and is proximate to an antenna of the transmitter;

said antenna being on said tower and at a distance from the processor;

amplify the vector following reception thereof at the location that is on the tower and is proximate to the antenna, by using an amplifier that is situated proximate to the antenna and on the tower; and

provide the amplified vector to the antenna.

47. The communications system according to claim 46, wherein the short-range link comprises a wireless link and a directional antenna.

48. The communications system according to claim 46, wherein the antenna comprises a two-dimensional array of antenna elements.

49. The communications system according to claim 46, wherein the short-range link comprises a multiplexer and a de-multiplexer.

50. A communications system comprising:

a processor that is configured to distribute a data element over a plurality of components/dimensions of a vector and is further configured to form the vector such that a component/dimension thereof comprises a superposition of a plurality of data elements; and

a transmitter that is configured to transmit the vector by transmitting a plurality of sub-carriers;

wherein the transmitter is configured to transmit at least two sub-carriers simultaneously in time therebetween; and

wherein the processor is further configured to form a first replica of the vector and a second replica of the vector; and

wherein the transmitter is configured to transmit the first replica of the vector using a first antenna element and to transmit the second replica of the vector using a second antenna element.

51. The communications system according to claim 50, wherein the processor is further configured to adjust at least one of the first replica of the vector and the second replica of the vector using at least one channel-dependent weight;

and wherein, following the adjustment, the transmitter is configured to transmit the first replica of the vector using the first antenna element and to transmit the second replica of the vector using the second antenna element, such that said first and second replicas of the vector that are transmitted are received at a receiving antenna and add coherently therebetween, on a voltage basis, at the receiving antenna.

52. A communications system comprising:

a processor that is configured to distribute a data element over a plurality of components/dimensions of a vector and is further configured to form the vector such that a component/dimension thereof comprises a superposition of a plurality of data elements; and

a transmitter that is configured to transmit the vector by transmitting a plurality of sub-carriers;

wherein the transmitter is configured to transmit at least two sub-carriers simultaneously in time therebetween; and

wherein the transmitter is further configured to transmit the vector over a plurality of frequency intervals that are non-contiguous therebetween and/or over a plurality of time intervals that are non-contiguous therebetween.

53. A communications system comprising:

a processor that is configured to distribute a data element over a plurality of components/dimensions of a vector and is further configured to form the vector such that a component/dimension thereof comprises a superposition of a plurality of data elements; and

a transmitter that is configured to transmit the vector by transmitting a plurality of sub-carriers;

wherein the transmitter is configured to transmit at least two sub-carriers simultaneously in time therebetween; and

wherein the transmitter that is configured to transmit the vector by transmitting a plurality of sub-carriers is further configured to;

amplify a first subset of the plurality of sub-carriers using a first amplifier; and

amplify a second subset of the plurality of sub-carriers using a second amplifier;

wherein each one of the first and second subsets of the plurality of sub-carriers comprises at least one sub-carrier of the plurality of sub-carriers.