Distribution of clipping noise between bands

Patent metadata

Field	Value
Publication number	US-11228330-B2
Application number	US-202017066960-A
Country	US
Kind code	B2
Filing date	Oct 9, 2020
Priority date	Oct 16, 2019
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

A method comprising: obtaining a first radio signal and a second radio signal, determining a first envelope signal based on the first radio signal and a second envelope signal based on the second radio signal, determining a preview envelope signal based on the first envelope signal and the second envelope signal, determining a common clipping gain signal based on the preview envelope signal, determining a first clipping gain signal based on the common clipping gain signal and a first weighing factor, determining a second clipping gain signal based on the common clipping gain signal and a second weighing factor, performing a first crest factor reduction for the first radio signal utilizing the first clipping gain signal, and performing a second crest factor reduction for the second radio signal utilizing the second clipping gain signal.

First claim

The invention claimed is:

1. An apparatus comprising at least one processor, and at least one non-transitory memory including a computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to:
obtain a first radio signal and a second radio signal, wherein the first radio signal is different from the second radio signal;
determine a first envelope signal based on the first radio signal and a second envelope signal based on the second radio signal, wherein the first envelope signal is different from the second envelope signal;
determine a preview envelope signal based on the first envelope signal and the second envelope signal;
determine a common clipping gain signal based on the preview envelope signal;
determine a first clipping gain signal based on the common clipping gain signal and a first weighing factor;
determine a second clipping gain signal based on the common clipping gain signal and a second weighing factor;
wherein the first clipping gain signal is different from the second clipping gain signal;
wherein the first weighing factor is different from the second weighing factor;
perform a first crest factor reduction for the first radio signal utilizing the first clipping gain signal; and
perform a second crest factor reduction for the second radio signal utilizing the second clipping gain signal.

2. An apparatus according to claim 1 , wherein at least one of the first clipping gain signal or the second clipping gain signal is constrained.

3. An apparatus according to claim 2 , wherein:
the first clipping gain signal is constrained with the first envelope signal and the first weighing factor to determine a first clipping gain constrain signal; or
the second clipping gain signal is constrained with the second envelope signal and the second weighing factor to determine a second clipping gain constrain signal.

4. An apparatus according to claim 1 , wherein the first radio signal is placed at a first radio frequency bandwidth and the second radio signal is placed at a second radio frequency bandwidth, different from the first radio frequency bandwidth.

5. An apparatus according to claim 1 , wherein the first and/or the second crest factor reduction comprises a plurality of crest factor reduction iterations.

6. An apparatus according to claim 1 , wherein the first and the second radio signals comprise a composite signal or a carrier signal.

7. An apparatus according to claim 1 wherein the at least one memory and the computer program code are further configured, with the at least one processor, to cause the apparatus to pulse shape and protect against over-clipping.

8. An apparatus according to claim 1 wherein the apparatus is a radio frequency unit.

9. An apparatus according to claim 1 wherein the apparatus is comprised in a terminal device or an access node.

10. An apparatus according to claim 1 , wherein the first weighing factor and the second weighing factor sum to a value, the value being less than one when there are more than two weighing factors, and the value being equal to one when there are two weighing factors.

11. A method comprising:
obtaining a first radio signal and a second radio signal, wherein the first radio signal is different from the second radio signal;
determining a first envelope signal based on the first radio signal and a second envelope signal based on the second radio signal, wherein the first envelope signal is different from the second envelope signal;
determining a preview envelope signal based on the first envelope signal and the second envelope signal;
determining a common clipping gain signal based on the preview envelope signal;
determining a first clipping gain signal based on the common clipping gain signal and a first weighing factor;
determining a second clipping gain signal based on the common clipping gain signal and a second weighing factor;
wherein the first clipping gain signal is different from the second clipping gain signal,
wherein the first weighing factor is different from the second weighing factor;
performing a first crest factor reduction for the first radio signal utilizing the first clipping gain signal; and
performing a second crest factor reduction for the second radio signal utilizing the second clipping gain signal.

12. A method according to claim 11 , wherein at least one of the first clipping gain signal or the second clipping gain signal is constrained.

13. A method according to claim 11 , wherein the first radio signal is placed at a first radio frequency bandwidth and the second radio signal is placed at a second radio frequency bandwidth, different from the first radio frequency bandwidth.

14. A method according to claim 11 wherein the first and/or the second crest factor reduction comprises a plurality of crest factor reduction iterations.

15. A method according to claim 11 , wherein the first and the second radio signals comprise a composite signal or a carrier signal.

16. A method according to claim 11 the method further comprising pulse shaping and protecting against over-clipping.

17. A non-transitory computer readable medium comprising program instructions for causing an apparatus to perform at least the following:
obtaining a first radio signal and a second radio signal, wherein the first radio signal is different from the second radio signal;
determining a first envelope signal based on the first radio signal and a second envelope signal based on the second radio signal, wherein the first envelope signal is different from the second envelope signal;
determining a preview envelope signal based on the first envelope signal and the second envelope signal;
determining a common clipping gain signal based on the preview envelope signal;
determining a first clipping gain signal based on the common clipping gain signal and a first weighing factor;
determining a second clipping gain signal based on the common clipping gain signal and a second weighing factor;
wherein the first clipping gain signal is different from the second clipping gain signal;
wherein the first weighing factor is different from the second weighing factor;
performing a first crest factor reduction for the first radio signal utilizing the first clipping gain signal; and
performing a second crest factor reduction for the second radio signal utilizing the second clipping gain signal.

18. A non-transitory computer readable medium according to claim 17 , wherein at least one of the first clipping gain signal or the second clipping gain signal is constrained.

19. A non-transitory computer readable medium according to claim 17 , wherein the first radio signal is placed at a first radio frequency bandwidth and the second radio signal is placed at a second radio frequency bandwidth, different from the first radio frequency bandwidth.

20. A non-transitory computer readable medium according to claim 17 wherein the first and/or the second crest factor reduction comprises a plurality of crest factor reduction iterations.

21. A non-transitory computer readable medium according to claim 17 , wherein the first and the second radio signals comprise a composite signal or a carrier signal.

22. A non-transitory computer readable medium according to claim 17 the non-transitory computer readable medium further comprising pulse shaping and protecting against over-clipping.

Assignees

• Nokia Solutions & Networks Oy

Inventors

• Haza Grzegorz
• Ceszkiel Radoslaw
• Wolff Gunter
• Jelonnek Björn

Classifications

• H03F2200/451

  the amplifier being a radio frequency amplifier · CPC title

• H03F1/3241

  using predistortion circuits (H03F1/3211, H03F1/3217 take precedence) · CPC title

• H04B1/0475

  with means for limiting noise, interference or distortion (H04B1/0483 takes precedence) · CPC title

• H04B1/14

  Automatic detuning arrangements · CPC title

• H04L27/2623 Primary

  Reduction thereof by clipping · CPC title