Multi-standard peak canceling circuitry

Patent metadata

Field	Value
Publication number	US-9485129-B1
Application number	US-201414325184-A
Country	US
Kind code	B1
Filing date	Jul 7, 2014
Priority date	Jul 7, 2014
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

Integrated circuits with wireless communications circuitry having peak cancelation circuitry operable to perform crest factor reduction is provided. The peak cancelation circuitry may receive at least first and second carrier waveforms and may include at least a first canceling pulse generator (CPG), a second CPG, a first peak detector for performing peak detection on the first waveform, a second peak detector for performing peak detection on the second waveform, a third peak detector for performing peak detection on a combined waveform of the first and second waveforms, and a pulse allocator that receives clipping information from the three peak detectors and that controls the amount of peak cancelation that is being performed by the two CPGs. The allocator may determine whether the combined waveform contains any peaks. In response to determining that the combined waveform does not contain any peaks, the CPGs may be configured in bypass mode.

First claim

What is claimed is:

1. Circuitry, comprising:
a first input that receives a first carrier waveform;
a second input that receives a second carrier waveform;
a first circuit that receives the first carrier waveform;
a second circuit that receives the second carrier waveform, wherein the first and second circuits perform peak cancelation operations on the first and second waveforms in a first mode and bypasses the peak cancellation operations in a second mode, and wherein the first and second circuits generate corresponding waveforms in the first and second modes;
a summing circuit that receives the first and second carrier waveforms from the first and second inputs, respectively, and that outputs a combined waveform; and
a peak detection circuit that receives the combined waveform from the summing circuit and that outputs values indicative of the mode in which the first and second circuits operate.

2. The circuitry defined in claim 1 , further comprising:
outputs that are coupled to at least one antenna.

3. The circuitry defined in claim 1 , wherein the first circuit performs a first adjustable amount of peak cancelation on the first carrier waveform, and wherein the second circuit performs a second adjustable amount of peak cancelation on the second carrier waveform.

4. The circuitry defined in claim 1 , further comprising:
a second peak detection circuit that performs peak detection operations on only the first carrier waveform; and
a third peak detection circuit that performs peak detection operations on only the second carrier waveform.

5. The circuitry defined in claim 1 , wherein the first carrier waveform is transmitted according to a first wireless standard, and wherein the second carrier waveform is transmitted according to a second wireless standard, the circuitry further comprising:
an allocation circuit that takes into account different performance requirements of the first and second wireless standards and that adjusts the amount of peak cancellation that is performed on the first and second carrier waveforms by the first and second circuits, respectively.

6. A method of operating peak cancelation circuitry, comprising:
receiving a first carrier waveform at a first input;
receiving a second carrier waveform at a second input;
with a summing circuit, combining the first and second carrier waveforms into an aggregated waveform;
with a peak detector, performing peak detection on the aggregated waveform and outputting a result;
with a first canceling pulse generator circuit, receiving the first carrier waveform, a first canceling pulse, and a first weighting factor that is computed from the result, and performing a first adjustable amount of peak canceling on the first carrier waveform based on the first canceling pulse and the first weighting factor to generate a corresponding first output waveform; and
with a second canceling pulse generator circuit, receiving the second carrier waveform, a second canceling pulse, and a second weighting factor that is computed from the result, and performing a second adjustable amount of peak canceling on the second carrier waveform based on the second canceling pulse and the second weighting factor to generate a corresponding second output waveform.

7. A method of operating peak cancelation circuitry, comprising:
receiving a first carrier waveform at a first input;
receiving a second carrier waveform at a second input;
with a first canceling pulse generator circuit, receiving the first carrier waveform and performing a first adjustable amount of peak canceling on the first carrier waveform and generating a corresponding first output waveform;
with a second canceling pulse generator circuit, receiving the second carrier waveform and performing a second adjustable amount of peak canceling on the second carrier waveform and generating a corresponding second output waveform;
summing the first and second output waveforms;
with a summing circuit, combining the first and second carrier waveforms into an aggregated waveform;
with a first peak detector, performing peak detection on the aggregated waveform;
with a second peak detector, receiving the first carrier waveform from the first input and performing peak detection on the first carrier waveform;
with a third peak detector, receiving the second carrier waveform from the second input and performing peak detection on the second carrier waveform; and
controlling the first and second canceling pulse generator circuits based on outputs of the first, second, and third peak detectors.

8. The method defined in claim 7 , further comprising:
with an allocation circuit, receiving clipping information from the first, second, and third peak detectors.

9. The method defined in claim 8 , further comprising:
with the allocation circuit, determining from the received clipping information whether the aggregated waveform contains any peaks.

10. The method defined in claim 9 , wherein controlling the first and second canceling pulse generator circuits comprises:
in response to determining that the aggregated waveform contains at least one peak, generating adjustable control signals to the first and second canceling pulse generator circuits with the allocation circuit.

11. The method defined in claim 9 , wherein controlling the first and second canceling pulse generator circuits comprises:
in response to determining that the aggregated waveform does not contain any peaks, configuring the first and second canceling pulse generator circuits in bypass mode with the allocation circuit.

12. Peak cancelation circuitry, comprising:
a first input that receives a first carrier waveform;
a second input that receives a second carrier waveform;
a first canceling pulse generator that receives the first carrier waveform from the first input;
a second canceling pulse generator that receives the second carrier waveform from the second input;
a summing circuit that receives the first carrier waveform from the first input, that receives the second carrier waveform from the second input, and that outputs a combined waveform; and
a pulse allocation circuit that receives clipping information on the first carrier waveform, the second carrier waveform, and the combined waveform and that outputs control signals that adjust the amount of peak cancelation that is being performed by the first and second canceling pulse generators on the first and second carrier waveforms.

13. The peak cancelation circuitry defined in claim 12 , further comprising:
a first peak detector that performs peak detection on only the first carrier waveform; and
a second peak detector that performs peak detection on only the second carrier waveform.

14. The peak cancelation circuitry defined in claim 13 , further comprising:
a third peak detector that performs peak detection on the combined waveform.

15. The peak cancelation circuitry defined in claim 12 , wherein the pulse allocation circuit configures the first and second canceling pulse generators in bypass mode in response to determining that the combined waveform does not contain any peaks.

Assignees

• Altera Corp

Inventors

• Cope Benjamin Thomas
• Mauer Volker
• Gheitanchi Shahin
• Safari Nima

Classifications

• H04L27/2623 Primary

  Reduction thereof by clipping · CPC title