Hybrid precoder

• US 9,900,064 B2
• Filed: 10/03/2013
• Issued: 02/20/2018
• Est. Priority Date: 10/03/2012
• Status: Active Grant

• Current Assignee: Sckipio Technologies S.I Ltd.
• Original Assignee: Sckipio Technologies S.I Ltd.
• Inventors: Verbin, Rami, Keren, Rani, Reina, Guy
• Primary Examiner(s): Oh, Andrew
• Application Number:
  US14/432,930
• Publication Number:
  US 20150244418A1
• Time in Patent Office: 1,601 Days
• Field of Search: None
• CPC Class Codes: H04B 2001/0416 having gain or transmission power control
• CPC Class Codes: H04B 3/32 Reducing cross-talk, e.g. by compensating
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04B 7/0417 Feedback systems
• 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 7/0686 Hybrid systems, i.e. switching and simultaneous transmission
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA

Abstract

A method employing linear precoding and non-linear precoding for transmitting data between at least two transmitters and a plurality of receivers via a plurality of communication channels over a plurality of subcarrier frequencies, the method comprising the procedures of transmitting by either one of said at least two transmitters, at least two training signals to respective said receivers; receiving by respective said receivers, said at least two training signals; evaluating channel characteristics of at least part of said communication channels, according to said at least two training signals; determining a precoding scheme selection that defines for at least part of said communication channels, over which of said subcarrier frequencies, said data transmitted shall be preceded using either one of linear precoding and non-linear precoding, according to evaluated said channel characteristics; precoding said data according to determined said precoding scheme selection; and transmitting said data according said precoding scheme selection.

Claims

1. A method employing linear precoding and non-linear precoding for transmitting payload data between at least two transmitters and a plurality of receivers via a plurality of communication channels, each said communication channel over a plurality of subcarrier frequencies, the method comprising the procedures of:

transmitting by at least one of said at least two transmitters, at least two training signals to respective said receivers;

receiving by respective said receivers, said at least two training signals;

evaluating communication channel characteristics of at least part of said communication channels, according to said at least two training signals;

determining a precoding scheme selection for each said subcarrier frequency whereby said payload data to be transmitted shall be precoded using either one of linear precoding and non-linear precoding, according to evaluated said channel characteristics;

precoding said payload data according to determined said precoding scheme selection; and

transmitting said payload data according said precoding scheme selection.

2. The method according to claim 1, wherein said communication channel characteristics are selected from a list consisting of:

respective responses of said communication channels;

signal-to-noise ratio (SNR);

level of far-end crosstalk (FEXT);

signal-to-FEXT ratio;

the signal-to-noise-plus-interference ratio (SNIR);

noise characteristics of said communication channels;

channel matrix elements of said communication channels for at least part of said subcarrier frequencies; and

attributes of said communication channels that influence transmission and reception parameters.

3. The method according to claim 1, wherein said precoding scheme selection is at least partly determined such that for said payload data transmitted over those said subcarrier frequencies exhibiting FEXT levels that are above a threshold value shall be said precoded using said non-linear precoding and said payload data transmitted over those said subcarrier frequencies exhibiting FEXT levels that are below said threshold value shall be said precoded using said linear precoding.

4. The method according to claim 1, wherein said precoding scheme selection is determined per subcarrier frequency in said subcarrier frequencies, independently.

5. The method according to claim 1, wherein said procedure of evaluating involves generating error signals by respective said receivers, wherein said error signals are determined by comparing received signals by said receivers to respective said at least two training signals.

6. The method according to claim 1, further comprising the procedure of determining whether each one of said at least two training signals are respectively to be either one of:

precoded, and non-precoded;

wherein in case said at least two training signals are determined to be said precoded, they shall be said transmitted over those said subcarrier frequencies determined to convey said payload data transmitted using said linear precoding, and in case said at least two training signals are determined to be non-precoded, they shall be transmitted over those said subcarrier frequencies determined to convey said transmitted payload payload data using said non-linear precoding.

7. The method according to claim 1, further comprising a procedure of receiving by at least one of said receivers said payload data which is precoded, wherein said at least one of said receivers applies a modulo arithmetic operation to said payload data said precoded by using said non-linear precoding.

8. The method according to claim 1, wherein said precoding scheme selection is communicated to said receivers.

9. A hybrid precoder system employing linear precoding and non-linear precoding for transmitting payload data between at least two transmitters and a plurality of receivers via a plurality of communication channels, each said communication channel over a plurality of subcarrier frequencies, the at least two transmitters are communicatively coupled, respectively, with the plurality of receivers, the hybrid precoder system comprising:

a linear precoder for linear precoding said payload data;

a non-linear precoder for non-linear precoding said payload data;

a controller coupled with said linear precoder and said non-linear precoder, said controller at least partly evaluates channel characteristics of at least part of said communication channels, said controller further determines a precoding scheme selection for each said subcarrier frequency whereby said payload data to be transmitted shall be precoded using either one of linear precoding and non-linear precoding, according to determined said channel characteristics; and

an input selector, coupled with said linear precoder and said non-linear precoder, said input selector selects which of the linear precoded payload data and the non-linear precoded payload data is outputted by said hybrid precoder system, according to said precoding scheme selection.

10. The hybrid precoder system according to claim 9, wherein said communication channel characteristics are selected from a list consisting of:

respective responses of said communication channels;

signal-to-noise ratio (SNR);

level of far-end crosstalk (FEXT);

signal-to-FEXT ratio;

the signal-to-noise-plus-interference ratio (SNIR);

noise characteristics of said communication channels;

channel matrix elements of said communication channels for at least part of said subcarrier frequencies; and

attributes of said communication channels that influence transmission and reception parameters.

11. The hybrid precoder system according to claim 9, wherein said precoding scheme selection is determined per subcarrier frequency in said subcarrier frequencies, independently.

12. The hybrid precoder system according to claim 9, wherein said at least two transmitters transmit said linear precoded payload data and said non-linear precoded payload data to respective said receivers, via respective said communication channels, according to said precoding scheme selection.

13. The hybrid precoder system according to claim 9, wherein said controller transmits said precoding scheme selection to said receivers via a forward logical channel, said forward logical channel couples said controller with said receivers.

14. The hybrid precoder system according to claim 9, wherein of said receivers apply modulo arithmetic operation to received said payload data said precoded by using said non-linear precoding, according to said precoding scheme selection.