RATE CONTROL WITH TRANSMITTER POWER OPTIMIZATION

• US 20200136661A1
• Filed: 10/30/2019
• Published: 04/30/2020
• Est. Priority Date: 10/31/2018
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Inventors: ELIAZ, Amir Dov, STAHL DISKIN, Nir, STOPLER, Daniel, GAIKWAD, Rohit, ERCEG, Vinko, AGARWAL, Peyush, ABDELAAL, Rana A., RYU, Hyoung Keun
• Granted Patent: US 11,777,539 B2
• Time in Patent Office: Days
• 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: H04W 52/0261 managing power supply demand, e.g. depending on battery level
• CPC Class Codes: H04W 52/228 using past power values or information
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 52/365 Power headroom reporting
• CPC Class Codes: H04W 52/52 using AGC [Automatic Gain Control] circuits or amplifiers

Abstract

A transmit power optimization and rate-control system includes a transmitter circuit having one or more power amplifiers transmit radio-frequency (RF) signals at a transmission (Tx) rate and a Tx power level. A receiver circuit receives RF signals, decodes the received RF signals and provides one or more Tx status feedbacks. A rate-control module adjusts the Tx rate based at least on a channel condition. A probing engine generates at least two consecutive frames at a first Tx power level, and a second Tx power level in response to a trigger causes the transmitter to transmit the at least two consecutive frames, and processes respective Tx status feedbacks received in response to transmission of the two consecutive frames in order to optimize the Tx power of the transmitter.

Claims

1. A transmit power optimization and rate-control system, the system comprising:

a transmitter circuit including one or more power amplifiers and configured to transmit radio-frequency (RF) signals at a transmission (Tx) rate and a Tx power level;

a receiver circuit configured to receive RF signals, decode the received RF signals and provide one or more Tx status feedbacks;

a rate-control module configured to adjust the Tx rate based at least on a channel condition; and

a probing engine configured to;

generate at least two frames at a first Tx power level and a second Tx power level in response to a trigger;

cause the transmitter to transmit the at least two frames; and

process respective Tx status feedbacks received in response to transmission of the at least two frames in order to optimize the Tx power of the transmitter.

2. The system of claim 1, wherein the rate-control module is further configured to determine an updated Tx rate based on the channel condition and an updated Tx power.

3. The system of claim 1, wherein the first Tx power level is determined by incrementing a current Tx power by a delta (Δ

) and the second Tx power level is determined by decrementing the current Tx power by the Δ

, wherein a value of the Δ

is within a range of about 0.1 dB to 0.7 dB.

4. The system of claim 3, further comprising a scheduler module configured to generate the trigger, and wherein each of the at least two frames comprise consecutive frames and include multiple consecutive probing packets.

5. The system of claim 1, wherein the at least two frames comprise consecutive frames including a +Δ

frame and a −

Δ

frame, and wherein each of the +Δ

frame and the −

Δ

frame is coupled with an aggregated media access control (MAC) protocol data unit (AMPDU).

6. The system of claim 5, wherein the probing engine is configured to retrieve a first packet success rate (PSR) from an acknowledgment (ACK) signal placed in a Tx status feedback corresponding to the +Δ

frame and retrieve a second PSR from an ACK signal placed in a Tx status feedback corresponding to the −

Δ

frame.

7. The system of claim 6, further comprising a Tx probing detector comprising a subtraction module, a filter and a control loop, wherein the Tx probing detector is configured to perform a power-level discrimination by subtracting the second PSR from the first PSR, filtering a PSR subtraction result and providing an adjustment to a current Tx power level based on the filtered PSR subtraction result.

8. The system of claim 7, wherein the power-level discrimination is seamless to the rate-control module and is configured to cause minor impact to a rate-control sensing.

9. The system of claim 1, wherein adjustment of the Tx rate and optimization of the Tx power are achieved by limiting an error vector magnitude (EVM) and maximizing a link throughput, and wherein the optimization of the Tx power optimizes receiver-side signal-plus-noise and distortion (SINAD).

10. The system of claim 1, wherein Tx power backoff is reflected from a previous Tx rate when a new Tx rate is selected.

11. The system of claim 10, wherein the receiver circuit is configured to generate a metric value for a link-budget gain based on a Tx power optimization, wherein the metric value is used to check whether the transmitter is capable of supporting the Tx power optimization and to enable a distortion recovery receiver (DRR) technique.

12. A method of Tx power optimization and rate control, the method comprising:

transmitting, by a transmitter circuit, RF signals at a Tx rate and a Tx power level, the RF signals including at least two frames at a first Tx power level and a second Tx power level;

receiving, from a receiver circuit, Tx status feedbacks in response to transmission of the at least two frames;

adjusting the Tx rate based at least on a channel condition; and

processing the received Tx status feedbacks to retrieve ACK signals relating to the at least two frames placed in the Tx status feedbacks in order to optimize the Tx power of the transmitter.

13. The method of claim 12, wherein the at least two frames comprise consecutive frames, and wherein adjusting the Tx rate is performed based on the channel condition and an updated Tx power.

14. The method of claim 12, further comprising determining the first Tx power level by incrementing a current Tx power by a delta (Δ

) and determining the second Tx power level by decrementing the current Tx power by the Δ

, wherein a value of the Δ

is within a range of about 0.1 dB to 0.7 dB.

15. The method of claim 14, further comprising retrieving a first packet success rate (PSR) from an ACK signal placed in a Tx status feedback corresponding to a +Δ

frame and retrieving a second PSR from an ACK signal placed in a Tx status feedback corresponding to a −

Δ

frame.

16. The method of claim 15, further comprising performing a power level discrimination by subtracting the second PSR from the first PSR, filtering a PSR subtraction result and providing an adjustment to a current Tx power level based on the filtered PSR subtraction result.

17. The method of claim 12, wherein adjustment of the Tx rate and optimization of the Tx power are achieved by limiting an EVM and maximizing a link throughput, and wherein the optimization of the Tx power optimizes receiver-side SINAD.

18. A station for facilitating communication in a wireless local area network, the station comprising:

one or more memories; and

one or more processors coupled to the one or more memories, the one or more processors configured to cause;

transmitting at least two frames at a first Tx power level and a second Tx power level;

processing a response frame indicating a Tx status feedback associated with the at least two frames;

determining a channel condition using the Tx status feedback;

adjusting a current Tx rate based on the channel condition; and

optimizing Tx power of a transmitter of the station based on the Tx status feedback associated with the at least two frames.

19. The station of claim 18, wherein the at least two frames comprise consecutive frames, and wherein the one or more processors is further configured to determine the first Tx power level by incrementing a current Tx power by a Δ

and to determine the second Tx power level by decrementing the current Tx power by the Δ

, wherein a value of the Δ

is within a range of about 0.3 dB to 0.7 dB.

20. The station of claim 19, wherein the one or more processors is further configured to:

retrieve a first PSR from an ACK signal placed in a Tx status feedback corresponding to a +Δ

frame and retrieve a second PSR from an ACK signal placed in a Tx status feedback corresponding to a −

Δ

frame; and

perform a power-level discrimination by subtracting the second PSR from the first PSR, filtering a PSR subtraction result and providing an adjustment to a current Tx power level based on the filtered PSR subtraction result.