METHOD AND APPARATUS FOR CONTROLLING UPLINK DATA TRANSMISSION IN WIRELESS COMMUNICATION SYSTEM

• US 20170127402A1
• Filed: 10/28/2016
• Published: 05/04/2017
• Est. Priority Date: 10/30/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kweon, Ki-Suk, Lim, Han-Na, Park, Jung-Shin, Lee, Joo-Hyung, Lee, Ji-Cheol, Lee, Jin-Sung, Lee, Hyung-Ho
• Granted Patent: US 10,462,793 B2
• Time in Patent Office: Days
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: H04W 72/52 based on load
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

The present disclosure relates 5G or pre-5G communication systems for supporting higher data transmission rate than those by LTE or other post-4G communication systems. Disclosed are a method and apparatus for determining a window size in a wireless communication system. The method includes determining an uplink data rate of the UE on a wireless link, determining that a maximum data size transmittable through an internet session including the wireless link is the window size for the internet session based on the uplink data rate, and transmitting uplink data through the internet session based on the determined window size.

Claims

1. A method for determining a window size in a wireless communication system, the method comprising:

determining an uplink data rate of a user equipment (UE) on a wireless link;

determining that a maximum data size transmittable through an internet session including the wireless link is the window size for the internet session based on the uplink data rate; and

transmitting uplink data through the internet session based on the determined window size.

2. The method of claim 1, wherein determining the uplink data rate comprises:

obtaining a number of resource blocks (nRB) and a modulation and coding scheme (MCS) assigned to the UE based on resource allocation information received from a base station;

determining a transport block size (TBS) based on the MCS and the nRB;

determining whether to use the MCS that is not set to 0 and updated last to determine the uplink data rate based on a throughput autocorrelation of the UE; and

determining that the TBS is the uplink data rate.

3. The method of claim 1, further comprising:

obtaining a number of resource blocks (nRB) and a modulation and coding scheme (MCS) assigned to the UE based on resource allocation information received from a base station;

determining an index corresponding to an MCS section where the MCS assigned to the UE belongs by referring to information on a plurality of the MCS sections each of which includes at least one MCS; and

determining the window size based on the index,

wherein the window size is determined by adding a reference window size corresponding to the index to a difference between the MCS assigned to the UE and an MCS corresponding to the reference window size and a predetermined weight.

4. The method of claim 1, wherein determining the uplink data rate comprises determining the uplink data rate using radio channel information that is not set to 0 and updated last when a first value indicating a time taken for a throughput autocorrelation value of the UE to decrease a predetermined value is larger than a second value indicating a length of a period during which uplink radio channel information received from a base station is not updated.

5. The method of claim 1, further comprising determining the window size based on channel quality information (CQI) measured for a downlink when a first value indicating a time taken for a throughput autocorrelation value of the UE to decrease a predetermined value is not larger than a second value indicating a length of a period during which uplink radio channel information received from a base station is not updated.

6. The method of claim 1, further comprising determining the window size according to an equation when a first value indicating a time taken for a throughput autocorrelation value of the UE to decrease a predetermined value is not larger than a second value indicating a length of a period during which uplink radio channel information received from a base station is not updated, wherein the equation is given:

CWND(t)=(CWND_latest−

CWND_default)exp{−

k(t−

t_latest)³}+CWND_default

k=f{CQI}

If, CQI_current−

CQI_latest>

0,f{CQI}=increasing value or increasing function

If, CQI_current−

CQI_latest>

0,f{CQI}=increasing value or increasing function

where CWND(t) means the window size at a time t, CWND_latest means the window size latest updated, CWND_default means a predetermined default window size, t_latest means a time when CWND_latest is determined, CQI_current means channel quality information (CQI) currently measured for a downlink, and CQI_latest means the CQI latest measured.

7. The method of claim 1, wherein when the current RSRP is not lower than a predetermined threshold, the window size is calculated according to an equation given:

CWND(t)=k*R(t)*S_RTT(t)/MSS,k<

1

R(t)=(1−

a)*R(t−

1)+a*f{RSRQ},a<

1

where CWND(t) means the window size at a time, k is a predetermined constant, R(t) is the uplink data rate estimated based on a current RSRQ and a past RSRQ, R(t−

1) means the uplink data rate estimated in the past, f{RSRQ} is a value related to the uplink data rate predicted based on the current RSRQ, S_RTT(t) is a minimum round trip time (RTT) of the internet session, and MSS is a maximum segment size transmittable through the internet session.

8. The method of claim 1, wherein determining the uplink data rate further comprises determining the uplink data rate based on at least one of a maximum data rate corresponding to an MCS used for the internet session and a data rate supported by an access point (AP) in which the UE accesses for the internet session.

9. The method of claim 1, wherein determining the window size further comprises computing the window size based on at least one of a signal strength measured by the UE, a load of an AP accessed by the UE for the internet session, or the uplink data rate, and

wherein the load of the AP is calculated based on a channel utilization included in a basic service set (BSS) load in a beacon signal received from the AP, and

wherein the load of the AP is estimated based on an interval between beacon signals received by the UE and a beacon interval received through a beacon signal from the AP at a time of determining the window size.

10. The method of claim 1, wherein the window size is calculated by an equation given:

11. An apparatus in a user equipment (UE) for determining a window size in a wireless communication system, the apparatus comprising:

a controller configured to;

determine an uplink data rate of the UE on a wireless link; and

determine that a maximum data size transmittable through an internet session including the wireless link is the window size for the internet session based on the uplink data rate; and

a transmitter configured to transmit uplink data through the internet session based on the determined window size.

12. The apparatus of claim 11, wherein the controller is further configured to:

obtain a number of resource blocks (nRB) and a modulation and coding scheme (MCS) assigned to the UE based on resource allocation information received from a base station,

determine a transport block size (TBS) based on the MCS and the nRB;

determine whether to use the MCS that is not set to 0 and updated last to determine the uplink data rate based on a throughput autocorrelation of the UE; and

determine that the TBS is the uplink data rate.

13. The apparatus of claim 11, wherein the controller is further configured to:

obtain a number of resource blocks (nRB) and a modulation and coding scheme (MCS) assigned to the UE based on resource allocation information received from a base station,

determine an index corresponding to an MCS section where the MCS assigned to the UE belongs by referring to information on a plurality of the MCS sections each of which includes at least one MCS; and

determine the window size based on the index, wherein the window size is determined by adding a reference window size corresponding to the index to a difference between the MCS assigned to the UE and an MCS corresponding to the reference window size and a predetermined weight.

14. The apparatus of claim 11, wherein the controller is further configured to determine the uplink data rate using radio channel information that is not set to 0 and updated last when a first value indicating a time taken for a throughput autocorrelation value of the UE to decrease a predetermined value is larger than a second value indicating a length of a period during which uplink radio channel information received from a base station is not updated.

15. The apparatus of claim 11, wherein the controller is further configured to determine the window size based on channel quality information (CQI) measured for a downlink when a first value indicating a time taken for a throughput autocorrelation value of the UE to decrease a predetermined value is not larger than a second value indicating a length of a period during which uplink radio channel information received from a base station is not updated.

16. The apparatus of claim 11, wherein the controller is configured to determine the window size according to an equation when a first value indicating a time taken for a throughput autocorrelation value of the UE to decrease a predetermined value is not larger than a second value indicating a length of a period during which uplink radio channel information received from a base station is not updated, wherein the equation is given:

CWND(t)=(CWND_latest−

CWND_default)exp{−

k(t−

t_latest)³}+CWND_default

k=f{CQI}

If, CQI_current−

CQI_latest>

0,f{CQI}=increasing value or increasing function

If, CQI_current−

CQI_latest>

0,f{CQI}=increasing value or increasing function

where CWND(t) means the window size at a time t, CWND_latest means the window size latest updated, CWND_default means a predetermined default window size, t_latest means a time when CWND_latest is determined, CQI_current means channel quality information (CQI) currently measured for a downlink, and CQI_latest means the CQI latest measured.

17. The apparatus of claim 11, wherein when the current RSRP is not lower than a predetermined threshold, the window size is calculated according to an equation given:

CWND(t)=k*R(t)*S_RTT(t)/MSS,k<

1

R(t)=(1−

a)*R(t−

1)+a*f{RSRQ},a<

1

where CWND(t) means the window size at a time, k is a predetermined constant, R(t) is the uplink data rate estimated based on a current RSRQ and a past RSRQ, R(t−

1) means the uplink data rate estimated in the past, f{RSRQ} is a value related to the uplink data rate predicted based on the current RSRQ, S_RTT(t) is a minimum round trip time (RTT) of the internet session, and MSS is a maximum segment size transmittable through the internet session.

18. The apparatus of claim 11, wherein the controller is further configured to determine the uplink data rate based on at least one of a maximum data rate corresponding to an MCS used for the internet session and

a data rate supported by an access point (AP) in which the UE accesses for the internet session.

19. The apparatus of claim 11, wherein the controller is further configured to calculate the window size based on at least one of a signal strength measured by the UE, a load of an AP accessed by the UE for the internet session, or the uplink data rate, and

wherein the load of the AP is calculated based on a channel utilization included in a basic service set (BSS) load in a beacon signal received from the AP, and

wherein the load of the AP is estimated based on an interval between beacon signals received by the UE and a beacon interval received through a beacon signal from the AP at a time of determining the window size.

20. The apparatus of claim 11, wherein the window size is calculated by an equation given: