Method and apparatus for controlling transmission rate of physical layer

Patent metadata

Field	Value
Publication number	US-9887802-B2
Application number	US-201514677266-A
Country	US
Kind code	B2
Filing date	Apr 2, 2015
Priority date	Aug 1, 2014
Publication date	Feb 6, 2018
Grant date	Feb 6, 2018

Abstract

Method and apparatus for controlling a physical layer protocol data unit (PPDU) transmission rate of a physical layer in a first terminal are provided. The method includes: obtaining a media access control protocol data unit (MPDU) retransmission frequency of the first terminal in a first period, where the first terminal is a station or an access point in a wireless network; if the MPDU retransmission frequency is less than a frequency threshold, promoting the PPDU transmission rate in a second period; and else, suppressing the PPDU transmission rate in the second period, where the second period is following and adjacent to the first period along a time axis. The PPDU transmission rate may be adjusted adaptively according to a channel's practical transmission state, the physical layer rate may be prevented from decreasing continuously in noisy channel environment, and a throughput rate may be improved in real time.

First claim

What is claimed is:

1. A method for controlling a physical layer protocol data unit (PPDU) transmission rate of a physical layer in a first terminal, comprising:
Obtaining a media access control protocol data unit (MPDU) retransmission frequency of the first terminal in a first period, where the first terminal is a station (STA) or an access point (AP) in a wireless network;
if the MPDU retransmission frequency is less than a frequency threshold, increasing the PPDU transmission rate of the physical layer in the first terminal in a second period;
if the MPDU retransmission frequency is greater than or equal to the frequency threshold, decreasing the PPDU transmission rate of the physical layer in the first terminal in the second period, where the second period is following and adjacent to the first period along a time axis; and
transmitting PPDUs with the increased PPDU transmission rate or the decreased PPDU transmission rate in the second period.

2. The method according to claim 1 , wherein obtaining the MPDU retransmission frequency comprises:
obtaining a first number, where the first number represents the number of MPDUs transmitted by the first terminal in the first period;
obtaining a second number, where the second number represents the number of MPDUs retransmitted by the first terminal in the first period;
if the first number is greater than or equal to a first threshold, determining the MPDU retransmission frequency based on Equation (1),

RR
=

Tx_Retry
⁢
_Cnt

Tx_Total
⁢
_Cnt

(
1
)

where RR represents the MPDU retransmission frequency, Tx_Total_Cnt represents the first number, and Tx_Retry_Cnt represents the second number; and
if the first number is less than the first threshold, determining the retransmission frequency to be zero.

3. The method according to claim 1 , wherein the frequency threshold increases with the increment of a noisy level of a channel.

4. The method according to claim 3 , wherein the noisy level of the channel decreases with the increment of a first ratio, where the first ratio is obtained based on Equation (2),
A=C/B   (2)

where A represents the first ratio, B represents the number of a first set of data comprising all first data received by the first terminal in the first period, C represents a second set of data comprising a portion of the first data received by the first terminal in the first period, where each media access control (MAC) target address of the second set of data is the first terminal, where the first data comprise aggregation frames and non-aggregation frames.

5. The method according to claim 3 , wherein the noisy level of the channel is determined based on a norm of the noisy level of the channel, and the norm of the noisy level of the channel is determined by:
obtaining a third number, where the third number represents the number of PPDUs received by the first terminal in the first period;
obtaining a fourth number, where the fourth number represents the number of Acknowledgement (ACK) frames or block ACK frames received by the first terminal in the first period;
obtaining a fifth number, where the fifth number represents the number of the first data received by the first terminal in the first period, which are not ACK frames or block ACK frames and whose MAC target addresses are the first terminal; and
if the difference between the third number and the fourth number is greater than or equal to a second threshold, determining the norm of the noisy level of the channel based on Equation (3),

CCA_Freq
=

1
-

Rx_MPDU
⁢
_Cnt

Rx_PPDU
⁢
_Cnt

-

Rx_ACK
⁢
_Cnt

(
3
)

where CCA_Freq represents the norm of the noisy level of the channel, Rx_PPDU_Cnt represents the third number, Rx_ACK_Cnt represents the fourth number, and Rx_MPDU_Cnt represents the fifth number.

6. The method according to claim 5 , further comprising: if the difference between the third number and the fourth number is less than the second threshold, determining the norm of the noisy level of the channel to be zero.

7. The method according to claim 5 , further comprising: determining the frequency threshold corresponding to the norm of the noisy level of the channel based on a first mapping relation.

8. The method according to claim 1 , wherein increasing the PPDU transmission rate of the physical layer in the first terminal in the second period comprises: if the PPDU transmission rate of the physical layer in the second period reaches a rate threshold, remaining the PPDU transmission rate of the physical layer in the second period.

9. The method according to claim 8 , wherein the rate threshold is related to first parameters, where the first parameters comprise powers or signal strength indication values of PPDUs received by the first terminal in the first period.

10. The method according to claim 9 , wherein the rate threshold is obtained by:
obtaining an average value of the first parameters received by the first terminal in the first period;
obtaining a rate corresponding to the average value according to a second mapping relation; and
determining the rate as the rate threshold, where the second mapping relation is determined based on a relation between sensitivity of a physical layer rate stipulated in the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard and the first parameters.

Assignees

• Spreadtrum Comm Shanghai Co

Inventors

• Xie Xin
• Jiang Ping
• Lv Xueli
• Chen Guochu

Classifications

• H04L1/20

  using signal quality detector · CPC title

• H04L1/0002 Primary

  by adapting the transmission rate · CPC title