Active scattering for bandwith enhanced MIMO

Patent metadata

Field	Value
Publication number	US-11368195-B2
Application number	US-201414288707-A
Country	US
Kind code	B2
Filing date	May 28, 2014
Priority date	May 28, 2014
Publication date	Jun 21, 2022
Grant date	Jun 21, 2022

Abstract

Embodiments of a communications system with multiple active scattering devices to service multiple users either indoor or outdoor over same spectrum in a communication network and a method for the system are generally described herein. Signals streams for transmission to users in spoke-and-hub configurations will utilize multiple active scattering devices. Three categories of operational concepts are presented: (1) multiple scattering devices arranged geometrically bundled together to function as active mirrors or retro-directive repeaters, (2) distributed man-made scattering devices placed to enhance channel bandwidth in between a hub and a common service area via frequency re-use, and (3) organizing distributed active scattering devices by remote beamforming for servicing a small common coverage area indoor or outdoor with enhanced bandwidth. All three techniques are for service with enhanced bandwidth and angular resolutions via frequency reuse, and extended service range via coherent operations of scattering devices.

First claim

What is claimed is:

1. A communications system comprising: a transmitter configured to send, in a communication channel, concurrently a plurality of independent streams of information to a plurality of receivers, the receivers being spatially separated, each of the receivers comprising a receiving element, the transmitter comprising transmitting elements which generate orthogonal beams (OBs) using a composited transfer function optimized based on channel state information of the communication channel and performance constraints associated with locations related to the communication channel; and
a plurality of active scattering devices distributed between the transmitter and the receivers, each of the active scattering devices being positioned in a direction with respect to a peak or a null of one of the OBs and configured to receive one of the independent streams of information sent by the transmitter and being further configured to re-radiate the received one of the independent streams of information to one of the receivers, the active scattering devices including a first active scattering device, the first active scattering device having an input and an output, both operating at a first frequency and comprising:
a first receiving section configured to receive at the input the one of the independent streams of information at the first frequency and output the received one of the independent streams of information at a second frequency, the second frequency being higher than the first frequency, and
a first re-radiating section configured to receive from the first receiving section the received one of the independent streams of information at the second frequency and re-radiate at the output the received one of the independent streams of information at the first frequency.

2. The communications system of claim 1 , wherein the active scattering devices are anchored on fixed platforms.

3. The communications system of claim 1 , wherein each of the active scattering devices is further configured to have a receiving section and a re-radiating section, the receiving section being configured to be in a field of view of the transmitter, the re-radiating section being configured to be in a field of view of the one of the receivers.

4. The communications system of claim 1 , wherein the transmitter further comprises a beam shaping processor for processing the independent streams of information and generating the OBs and outputting the generated OBs to the transmitting elements for transmission.

5. The communications system of claim 4 , wherein one of the generated beams is generated under directional constraints with radiation power favoring a direction toward one of the active scattering devices while discriminating against directions toward remaining ones of the active scattering devices.

6. The communications system of claim 4 , wherein one of the generated beams is generated under concurrent performance constraints on power reception at each of the receivers such that the one of the generated beams directionally favors one of the receiving elements while directionally discriminates against remaining ones of the receiving elements, the power reception at each of the receivers being from re-radiation of the active scattering devices.

7. The communications system of claim 4 , wherein the transmitter further comprises a wavefront multiplexing processor for processing the independent streams of information and outputting the processed independent streams of information to the beam shaping processor.

8. The communications system of claim 1 , wherein the transmitter further comprises a spatial processor for MIMO processing the independent streams of information and outputting the MIMO processed independent streams of information to the transmitting elements to radiate the MIMO processed independent streams of information to the receivers, wherein the MIMO processing comprises measuring current channel state information and optimizing transfer functions from the transmitting elements of the transmitter to the receiving elements of the receivers under concurrent performance constraints with radiation power favoring a direction toward one of the receiving elements while discriminating against directions toward remaining ones of the receiving elements.

9. The communications system of claim 1 , wherein each of the active scattering devices comprises at least one amplifier.

10. The communications system of claim 1 wherein one of the active scattering devices is positioned in a direction aligned with the peak or the null of one of the OBs.

11. The communications system of claim 1 wherein one of the active scattering devices is positioned in a direction significantly off from the peak or the null of one of the OBs.

12. A communications system comprising:
a transmitter operating in a communication channel and comprising a digital beam forming processor, the transmitter generating orthogonal beams (OBs) using a composited transfer function optimized based on channel state information of the communication channel and performance constraints associated with locations related to the communication channel;
a plurality of receivers; and
a plurality of active scattering devices distributed between the transmitter and the receivers;
wherein each of the plurality of active scattering devices is positioned in a direction with respect to a peak or a null of one of the OBs;
wherein each of the active scattering devices comprises a receiving section and a re-radiating section, the re-radiating sections operating as transmitting elements of a digital beam forming array at a first frequency, and
wherein the digital beam forming processor processes concurrently a plurality of input signals and generates concurrently a plurality of element signals using remote beam forming processing and transmitting the element signals to the re-radiating sections via feeder-links at a second frequency, the second frequency being higher than the first frequency, the re-radiating section receiving the element signals at the second frequency.

13. The communications system of claim 12 , wherein the remote beam forming processing is configured to form a plurality of shaped beams concurrently.

14. The communications system of claim 12 , wherein the transmitting elements are distributed on-a plurality of platforms.

15. The communications system of claim 12 , wherein the digital beam forming processor generates the element signals under concurrent performance constraints with radiation power favoring a direction toward one of the receivers while discriminating against directions toward remaining ones of the receivers.

16. The communications system of claim 12 , wherein the transmitter further comprises a wavefront multiplexing processor for processing concurrently a plurality of independent streams of information and outputting the processed independent streams of information as the input signals to the digital beam forming processor.

17. The communications system of claim 12 , wherein the digital beam forming processor transforms the input signals into a plurality of weighted input signals and generates each of the element signals as a sum of the weighted input signals.

18. The communications system of claim 12 , wherein the digital beam forming array forms a plurality of shaped beams concurrently tracking the receivers dynamically.

19. The communications system of claim 12 , wherein each of the active scattering devices comprises at least one amplifier.

20. A communications system c

Assignees

• Chang Donald C D
• Lee Juo Yu
• Spatial Digital Systems Inc

Inventors

• Chang Donald C D
• Lee Juo-Yu

Classifications

• H04B7/0452 Primary

  Multi-user MIMO systems · CPC title

• H04W72/046

  the resource being in the space domain, e.g. beams · CPC title

• H04W16/28

  using beam steering · CPC title

• H04B7/15535

  Control of relay amplifier gain (amplifier gain control in general H03G3/00; gain control reducing self - or loop interference H04B7/15578) · CPC title