POWER AMPLIFICATION APPARATUS FOR MASSIVE MIMO BASE STATIONS

• US 20160365906A1
• Filed: 06/12/2015
• Published: 12/15/2016
• Est. Priority Date: 06/12/2015
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Mobile Communications Incorporated (Sony Group Corp.)
• Inventors: KUSUNOKI, Shigeo
• Granted Patent: US 10,187,093 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H04B 1/0475 with means for limiting noise, interference or distortion H04B1/0483 takes precedence
• CPC Class Codes: H04B 2001/0408 with power amplifiers
• CPC Class Codes: H04B 7/0413 MIMO systems

Abstract

A Multi-Input Multi-Output base station includes a plurality of transmitter blocks. Each block includes a time-domain base band signal source circuit that generates an output, a low pass filter circuit coupled to the base band source circuit that filters the output of the base band source circuit, and a signal level adjuster circuit coupled to the base band signal source circuit and the low pass filter and that adjusts the output of the base band signal source circuit based on an output of the low pass filter.

Claims

1. A Multi-Input Multi-Output base station comprising:

a plurality of transmitter blocks, each including

a time-domain base band signal source circuit configured to generate an output;

a low pass filter circuit coupled to the base band source circuit and configured to filter the output of the base band source circuit; and

a signal level adjuster circuit coupled to the base band signal source circuit and the low pass filter and configured to adjust the output of the base band signal source circuit based on an output of the low pass filter.

2. The Multi-Input Multi-Output base station according to claim 1, wherein the output of the base band signal source circuit is coupled to a signal input of the signal level adjuster circuit, the output of the low pass filter circuit is coupled to a control input of the signal level adjuster circuit, and an output of the signal level adjuster corresponds to an adjusted output of the base band signal source circuit.

3. The Multi-Input Multi-Output base station according to claim 1 wherein the signal level adjuster circuit further comprises:

a reference voltage generator circuit configured to generate a reference voltage;

a signal multiplier circuit configured to generate a plurality of multiplier signals; and

circuitry configured to determine a multiplier signal of the plurality of multiplier signals generated by the signal multiplier circuit with which to adjust the output of the base band signal source circuit based on the output of the low pass filter circuit.

4. The Multi-Input Multi-Output base station according to claim 3, wherein the circuitry includes a comparator circuit configured to compare the output of the low pass filter circuit to the reference voltage, and a selector circuit configured to select one of the plurality of multiplier signals based on an output of the comparator circuit.

5. The Multi-Input Multi-Output base station according to claim 3 wherein a first of the plurality of multiplier signals is greater than a second of the plurality of multiplier signals.

6. The Multi-Input Multi-Output base station according to claim 5, wherein the circuitry is configured to select the second of the plurality of multiplier signals when the output of the low pass filter circuit is greater than the reference voltage.

7. The Multi-Input Multi-Output base station according to claim 5, wherein the circuitry is configured to select the second of the plurality of multiplier signals when the output of the low pass filter circuit is greater than the reference voltage.

8. The Multi-Input Multi-Output base station according to claim 3, wherein the signal level adjuster circuit is configured to adjust the output of the base band signal source circuit using a look up table of predetermined compensation values.

9. The Multi-Input Multi-Output base station according to claim 8, wherein each of the transmitter blocks further include a power amplifier circuit, and the compensation values in the look-up table compensate for nonlinearity in the power amplifier circuit.

10. The Multi-Input Multi-Output base station according to claim 1, wherein the signal level adjuster circuit is further configured to receive an output from at least one other transmitter block.

11. The Multi-Input Multi-Output base station according to claim 8 further comprising:

a pre-coder circuit coupled to a data source and configured to pre-code data from the data source according to the following equation

X=H^H*G<sup>−

1</sup>*S

where H is a channel matrix

H^H is a conjugate transpose of the channel matrix;

G=H*H^H

G<sup>−

1</sup> is the inverse of G.

16. The Multi-Input Multi-Output base station according to claim 1, wherein the base station includes at least one hundred transmitter blocks.

12. A Multi-Input Multi-Output system, comprising:

circuitry configured to

generate an output signal,

low pass filter the output signal to generate a filtered output signal; and

adjust the output signal based on the filtered output signal.

13. The Multi-Input Multi-Output system according to claim 12, wherein the circuitry is further configured to

generate a reference voltage,

generate a plurality of multiplier signals, and

determine one of the plurality of multiplier signals with which to adjust the output signal based on the filtered output signal.

14. A method for each of a plurality of transmitter blocks in a Multi-Input Multi-Output base station, comprising:

generating, with circuitry, a reference voltage;

generating, with the circuitry, a plurality of multiplier signals; and

determining, with the circuitry, one of the plurality of multiplier signals with which to adjust the output signal based on the filtered output signal.

15. The method according to claim 14, further comprising:

generating, with the circuitry, a reference voltage;

generating, with the circuitry, a plurality of multiplier signals; and

determining, with the circuitry, one of the plurality of multiplier signals with which to adjust the output signal based on the filtered signal.