APPARATUS, METHODS, AND ARTICLES OF MANUFACTURE FOR WIRELESS COMMUNICATIONS

• US 20120263056A1
• Filed: 04/05/2012
• Published: 10/18/2012
• Est. Priority Date: 04/15/2011
• Status: Abandoned Application

• Current Assignee: Ziva Corporation
• Original Assignee: Ziva Corporation
• Inventors: Smith, David, Husain, Anis, Achour, Maha, Rode, Jeremy
• Application Number:
  US13/440,796
• Publication Number:
  US 20120263056A1
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H01Q 1/523 between antennas of an array
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H04B 7/06 at the transmitting station
• CPC Class Codes: H04B 7/08 at the receiving station
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0228 with direct estimation from sounding signals

Abstract

Selected embodiments are directed to methods, apparatus, and articles of manufacture for wireless radio frequency communications. Adjacent antenna array elements of a receiver antenna array are separated by less than the diffraction limit of the radio frequency communication band in which the apparatus and methods operate. A plurality or multiplicity of near-field scatterers are asymmetrically placed in the immediate vicinity of each of the antenna array elements, to perturb the pattern of each of the antenna elements, making the patterns different even below diffraction limit spacing. A transmitter spatially and temporally focuses simultaneous transmissions on each of the antenna array elements, using time reversal communication techniques. The transmitter may transmit through multiple antenna elements, and the channel from the transmitter to the receiver may be subject to multipath phenomena.

Claims

1. A radio antenna array, comprising:

a plurality of antenna elements electrically insulated from each other, each antenna element of the plurality of antenna elements being configured to operate in a predetermined radio frequency (RF) band; and

a plurality of near-field (NF) scatterers;

wherein;

the plurality of antenna elements comprises a first antenna element and a second antenna element, the first antenna element being separated from the second antenna element by a distance d, d being less than one-half wavelength at center frequency of the predetermined RF band; and

the NF scatterers of the plurality of NF scatterers arc distributed asymmetrically relative to the first and second antenna elements, each NF scatterer of a first subset of the NF scatterers of the plurality of NF scatterers is located nearer the first antenna element than d.

2. A radio antenna array according to claim 1, wherein:

each NF scatterer of a second subset of the NF scatterers of the plurality of NF scatterers is located nearer the second antenna element than d; and

each antenna element of the array of antenna elements is coupled to a different input of a receiver.

3. An apparatus for receiving data transmissions, the apparatus comprising:

the radio antenna array according to claim 2; and

an electronic receiver portion configured to operate in the predetermined frequency band using time reversal, the electronic receiver portion comprising a plurality of antenna inputs, each antenna element of the array of antenna elements being coupled to a different input of the plurality of antenna inputs of the electronic receiver portion;

wherein d is less than one-half wavelength at all frequencies of the predetermined RF band.

4. An apparatus for receiving data transmissions according to claim 3, wherein the plurality of antenna elements comprises more than two antenna elements, and each pair of adjacent antenna elements of the plurality of antenna elements is separated by a distance not greater than d.

5. An apparatus for receiving data transmissions according to claim 4, wherein d is not more than ⅕

wavelength at all frequencies of the predetermined RF band.

6. An apparatus for receiving data transmissions according to claim 4, wherein d is not more than 1/10 wavelength at all frequencies of the predetermined RF band.

7. An apparatus for receiving data transmissions according to claim 4, wherein d is not more than 1/30 wavelength at all frequencies of the predetermined RF band.

8. An apparatus for receiving data transmissions according to claim 4, wherein d is not more than 1/15 wavelength at all frequencies of the predetermined RF band.

9. An apparatus for receiving data transmissions according to claim 8, wherein:

each NF scatterer of the first subset of the NF scatterers of the plurality of NF scatterers is located nearer the first antenna element than s; and

each NF scatterer of the second subset of the NF scatterers of the plurality of NF scatterers is located nearer the second antenna element than s; and

s is less than 0.02 wavelength at all frequencies of the predetermined RF band.

10. An apparatus for receiving data transmissions according to claim 8, wherein:

each NF scatterer of the first subset of the NF scatterers of the plurality of NF scatterers is located nearer the first antenna element than s; and

each NF scatterer of the second subset of the NF scatterers of the plurality of NF scatterers is located nearer the second antenna element than s; and

s is less than 0.01 wavelength at all frequencies of the predetermined RF band.

11. An apparatus for receiving data transmissions according to claim 8, wherein:

each NF scatterer of the first subset of the NF scatterers of the plurality of NF scatterers is located nearer the first antenna element than s; and

each NF scatterer of the second subset of the NF scatterers of the plurality of NF scatterers is located nearer the second antenna element than s; and

s is less than 0.03 wavelength at all frequencies of the predetermined RF band.

12. An apparatus for receiving data transmissions according to claim 8, wherein:

each NF scatterer of the first subset of the NF scatterers of the plurality of NF scatterers is located nearer the first antenna element than s; and

each NF scatterer of the second subset of the NF scatterers of the plurality of NF scatterers is located nearer the second antenna element than s; and

s is less than 0.05 wavelength at all frequencies of the predetermined RF band.

13. An apparatus for receiving data transmissions according to claim 12, wherein the plurality of NF scatterers comprises at least 100 NF scatterers.

15. An apparatus for receiving data transmissions according to claim 12, wherein the plurality of NF scatterers comprises at least 12 NF scatterers.

16. An apparatus for receiving data transmissions according to claim 15, wherein polarization of each NF scatterer of the plurality of NF scatterers is identical or substantially identical to polarization of the first and second antenna elements.

17. An apparatus for receiving data transmissions according to claim 15, wherein lengths of the NF scatterers of the plurality of NF scatterers vary to increase operating bandwidth of the radio antenna array.

14. An apparatus for receiving data transmissions according to claim 40, wherein the plurality of NF scatterers comprises at least 40 NF scatterers.

18. An apparatus for receiving radio frequency data transmissions, the apparatus comprising:

an electronic receiver configured to operate in a predetermined frequency band using time reversal, the electronic receiver comprising a plurality of antenna inputs; and

a multi-element antenna means for receiving electronic transmissions in the predetermined frequency band separately targeting each element of the multi-element antenna means;

wherein elements of the multi-element antenna means are spaced less than diffraction limit of the predetermined frequency band.

19. A method of transmitting data wirelessly from a transmitter to a receiver using time reversal communications in a predetermined radio frequency band, the method comprising:

estimating a first channel response between the transmitter and a first antenna element of the receiver;

estimating a second channel response between the transmitter and a second antenna element of the receiver;

temporally and spatially focusing a first transmission of first data from the transmitter on the first antenna element; and

temporally and spatially focusing a second transmission of second data from the transmitter on the second antenna element, the second antenna element being separated from the first antenna element by less than diffraction limit associated with the predetermined radio frequency band;

wherein the first and second transmissions are sent concurrently.

20. A method of receiving data wirelessly from a transmitter at a receiver using time reversal communications in a predetermined radio frequency band, the method comprising:

sending a first sounding pulse from a first antenna element of the receiver to the transmitter;

sending a second sounding pulse from a second antenna element of the receiver to the transmitter;

receiving at the receiver through the first antenna element a first transmission temporally and spatially focused by the transmitter on the first antenna element; and

receiving at the receiver through the first antenna element a first transmission temporally and spatially focused by the transmitter on the first antenna element, the second antenna element being separated from the first antenna element by less than diffraction limit associated with the predetermined radio frequency band;

wherein the first and second transmissions are received concurrently.