Multi-user transmissions

• US 9,391,745 B2
• Filed: 02/12/2016
• Issued: 07/12/2016
• Est. Priority Date: 06/13/2000
• Status: Expired due to Term

• Current Assignee: Comcast Cable Communications LLC (Comcast Corporation)
• Original Assignee: Comcast Cable Communications LLC (Comcast Corporation)
• Inventors: Agee, Brian G., Bromberg, Matthew C.
• Primary Examiner(s): ODOM, CURTIS B
• Application Number:
  US15/042,280
• Publication Number:
  US 20160164647A1
• Time in Patent Office: 151 Days
• US Class Current: 1/1
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0443 utilizing "waterfilling" technique
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0465 taking power constraints at power amplifier or emission constraints, e.g. constant modulus, into account
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity
• CPC Class Codes: H04L 27/26 Systems using multi-frequency codes H04L27/32 takes precedence
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 27/2605 Symbol extensions, e.g. Zero Tail, Unique Word [UW]
• CPC Class Codes: H04L 27/2607 Cyclic extensions
• CPC Class Codes: H04L 27/2627 Modulators
• CPC Class Codes: H04L 27/2646 using feedback from receiver for adjusting OFDM transmission parameters, e.g. transmission timing or guard interval length
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 40/04 based on wireless node resources
• CPC Class Codes: H04W 52/241 : taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/265 : taking into account the quality of service QoS
• CPC Class Codes: H04W 52/42 : in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 72/00 : Local resource management
• CPC Class Codes: H04W 72/04 : Wireless resource allocation
• CPC Class Codes: H04W 72/044 : based on the type of the allocated resource
• CPC Class Codes: H04W 72/0453 : Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/23 : in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/542 : using measured or perceived quality
• CPC Class Codes: H04W 88/08 : Access point devices
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

Methods and systems are described for orthogonal frequency division multiplexing (OFDM) transmission of data associated with multiple nodes and/or users. A plurality of weights may be determined based on, for example, feedback from one or more nodes. The feedback from each node may be indicative of weighting information. A multiple-input multiple-output (MIMO)-capable node may transmit OFDM transmissions, which may be time and frequency coincident, using the plurality of weights. For example, the MIMO-capable node may transmit a first OFDM transmission using at least a first weight of the plurality of weights and a second OFDM transmission using at least a second weight of the plurality of weights. This may allow the MIMO-capable node to, for example, transmit OFDM transmissions to multiple users via one or more common time-frequency channels.

Claims

1. A method comprising:

receiving, from a first node, first feedback indicative of first weighting information;

receiving, from a second node, second feedback indicative of second weighting information;

determining, based at least in part on the first feedback and the second feedback, a plurality of weights; and

transmitting, via an antenna array of a multiple-input multiple-output (MIMO)-capable third node;

a first orthogonal frequency division multiplexing (OFDM) transmission, using at least a first weight of the plurality of weights, that comprises first data associated with the first node; and

a second OFDM transmission, using at least a second weight of the plurality of weights, that comprises second data associated with the second node,

wherein the first OFDM transmission and the second OFDM transmission are time and frequency coincident.

2. The method of claim 1, wherein the first weighting information identifies a first weighting to be used for transmission by the MIMO-capable third node and the second weighting information identifies a second weighting to be used for transmission by the MIMO-capable third node.

3. The method of claim 1, wherein the first feedback is based at least in part on interference observed by the first node and the second feedback is based at least in part on interference observed by the second node.

4. The method of claim 1, wherein the transmitting comprises transmitting at least the first OFDM transmission and the second OFDM transmission using a multiple access scheme.

5. The method of claim 1, wherein the first OFDM transmission and the second OFDM transmission being time and frequency coincident comprises transmitting the first OFDM transmission via at least a first time-frequency channel and the second OFDM transmission via at least the first time-frequency channel.

6. The method of claim 1, wherein the first data comprises a first OFDM symbol and the second data comprises a second OFDM symbol.

7. The method of claim 1, wherein the transmitting comprises transmitting the first OFDM transmission via at least a first antenna of the antenna array and transmitting the second OFDM transmission via at least a second antenna of the antenna array.

8. The method of claim 1, wherein one or both of the first OFDM transmission or the second OFDM transmission comprises at least one of a rank 1 OFDM transmission or a rank 2 OFDM transmission.

9. A method comprising:

receiving, from a first node, first feedback indicative of first weighting information;

receiving, from a second node, second feedback indicative of second weighting information;

determining, based at least in part on the first feedback and the second feedback, a plurality of weights;

transmitting, via at least one antenna of an antenna array of a multiple-input multiple-output (MIMO)-capable third node, via at least a first time-frequency channel, and using at least a first weight of the plurality of weights, a first orthogonal frequency division multiplexing (OFDM) transmission that comprises first data associated with the first node; and

transmitting, via one or more antennas of the antenna array, via at least the first time-frequency channel, and using at least a second weight of the plurality of weights, a second OFDM transmission that comprises second data associated with the second node.

10. The method of claim 9, wherein the first weighting information identifies a first weighting to be used for transmission by the MIMO-capable third node and the second weighting information identifies a second weighting to be used for transmission by the MIMO-capable third node.

11. The method of claim 9, wherein the first feedback is based at least in part on interference observed by the first node and the second feedback is based at least in part on interference observed by the second node.

12. The method of claim 9, wherein the transmitting the first OFDM transmission and the transmitting the second OFDM transmission comprise transmitting at least the first OFDM transmission and the second OFDM transmission using a multiple access scheme.

13. The method of claim 9, wherein the first time-frequency channel comprises a plurality of tones.

14. The method of claim 9, wherein the first data comprises a first OFDM symbol and the second data comprises a second OFDM symbol.

15. The method of claim 9, wherein:

the transmitting the first OFDM transmission via the at least one antenna comprises transmitting the first OFDM transmission via at least a first antenna of the antenna array; and

the transmitting the second OFDM transmission via the one or more antennas comprises transmitting the first OFDM transmission via at least a second antenna of the antenna array.

16. The method of claim 9, further comprising selecting the first time-frequency channel based at least in part on the first feedback and the second feedback.

17. A method comprising:

receiving, from a first node, a first uplink transmission indicative of first weighting information;

receiving, from a second node, a second uplink transmission indicative of second weighting information;

determining, based at least in part on the first uplink transmission and the second uplink transmission, a plurality of weights;

transmitting, via at least one antenna of a plurality of antennas of a multiple-input multiple-output (MIMO)-capable third node and using at least a first weight of the plurality of weights, a first orthogonal frequency division multiplexing (OFDM) downlink transmission that comprises first data associated with the first node; and

transmitting, via one or more antennas of the plurality of antennas and using at least a second weight of the plurality of weights, a second OFDM downlink transmission that comprises second data associated with the second node,

wherein the first OFDM downlink transmission and the second OFDM downlink transmission are time and frequency coincident.

18. The method of claim 17, wherein the first weighting information identifies a first weighting to be used for downlink transmission by the MIMO-capable third node and the second weighting information identifies a second weighting to be used for downlink transmission by the MIMO-capable third node.

19. The method of claim 17, wherein the first uplink transmission is based at least in part on interference observed by the first node and the second uplink transmission is based at least in part on interference observed by the second node.

20. The method of claim 17, wherein the transmitting the first OFDM downlink transmission and the transmitting the second OFDM downlink transmission comprise transmitting at least the first OFDM downlink transmission and the second OFDM downlink transmission using a multiple access scheme.

21. The method of claim 17, wherein the first data comprises a first OFDM symbol and the second data comprises a second OFDM symbol.

22. The method of claim 17, wherein:

the transmitting the first OFDM transmission via the at least one antenna comprises transmitting the first OFDM transmission via at least a first antenna of the plurality of antennas; and

the transmitting the second OFDM transmission via the one or more antennas comprises transmitting the first OFDM transmission via at least a second antenna of the plurality of antennas.

23. The method of claim 17, further comprising selecting, based at least in part on the first uplink transmission and the second uplink transmission, at least a first time-frequency channel, wherein the first OFDM downlink transmission and the second OFDM downlink transmission being time and frequency coincident comprises transmitting the first OFDM downlink transmission via at least the first time-frequency channel and the second OFDM downlink transmission via at least the first time-frequency channel.

24. A method comprising:

receiving, from a first node, first feedback indicative of first weighting information;

receiving, from a second node, second feedback indicative of second weighting information;

determining, based at least in part on the first feedback and the second feedback, a plurality of weights; and

transmitting, by a multiple-input multiple-output (MIMO)-capable third node, via one or more antennas of a plurality of antennas and using orthogonal frequency division multiplexing (OFDM);

first data, associated with the first node, using at least a first weight of the plurality of weights; and

second data, associated with the second node, using at least a second weight of the plurality of weights,

wherein the transmitting the first data is time and frequency coincident with the transmitting the second data.

25. The method of claim 24, wherein the first weighting information identifies a first weighting to be used for transmission by the MIMO-capable third node and the second weighting information identifies a second weighting to be used for transmission by the MIMO-capable third node.

26. The method of claim 24, wherein the first feedback is based at least in part on interference observed by the first node and the second feedback is based at least in part on interference observed by the second node.

27. The method of claim 24, wherein the transmitting comprises transmitting at least the first data and the second data using a multiple access scheme.

28. The method of claim 24, wherein the transmitting the first data time and frequency coincident with the transmitting the second data comprises transmitting the first data via at least a first time-frequency channel and the second data via at least the first time-frequency channel.

29. The method of claim 24, wherein the first data comprises a first OFDM symbol and the second data comprises a second OFDM symbol.

30. The method of claim 24, wherein the transmitting comprises transmitting the first data and the second data via different antennas of the plurality of antennas.