Method and device for transmitting uplink information

• US 10,624,047 B2
• Filed: 05/15/2017
• Issued: 04/14/2020
• Est. Priority Date: 05/13/2016
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Li, Yingyang, Wang, Yi, Zhang, Shichang
• Primary Examiner(s): Sorowar, Golam
• Application Number:
  US16/099,008
• Publication Number:
  US 20190159143A1
• Time in Patent Office: 1,065 Days
• CPC Class Codes: H04W 52/08 Closed loop power control
• CPC Class Codes: H04W 52/14 Separate analysis of uplink or downlink
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0473 the resource being transmission power
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/02 Hybrid access
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]
• CPC Class Codes: H04W 74/0816 with collision avoidance
• CPC Class Codes: H04W 80/08 Upper layer protocols network arrangements or communication protocols for networked applications H04L67/00

Abstract

The present disclosure relates to a communication method and system for converging a 5^th-Generation (5G) communication system for supporting higher data rates beyond a 4^th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. The present application provides a method for transmitting uplink information, which includes the following: a UE detects control information, i.e., UL-Grant for scheduling uplink data transmissions from a base station; determines according to the control information, the number of PRBs resource allocated by the base station, determining a maximum transmission power allowed in the current sub-frame, determines an uplink transmission power of the UE; executes an LBT according to UL-Grant configurations, and starts an uplink data transmission after the LBT is successful. By adopting the method of the present disclosure, the total uplink transmission power of an entire cell in one sub-frame is controlled, so as to realize coexistence with other devices. Further, by reasonably setting an LBT time period and power increase transition time, the probability of collisions among devices is reduced.

Claims

1. A method for transmitting uplink information, the method comprising:

detecting, by a user equipment (UE), control information including uplink (UL)-Grant for scheduling uplink data transmissions;

determining a maximum transmission power allowed in a current sub-frame according to the control information including the UL-Grant;

determining an uplink transmission power of the UE;

executing listen before talk (LBT) according to the UL-Grant;

increasing the uplink transmission power of the UE to a certain strength Pa in a time period of Ta after a power increase transition time starts, wherein Ta and Pa are selected so that a channel is to be detected as busy by other devices nearby after the power increase transition time of a device starts, in case that the LBT is successful; and

performing an uplink data transmission according to the increased uplink transmission power, in case that the LBT is successful.

2. The method of claim 1, wherein determining the maximum transmission power allowed in the current sub-frame, comprises:

determining, according to a power offset P_O,c, the maximum transmission power allowed of the UE by P_CMAX,c(i)+P_O,c, and

wherein the determining the uplink transmission power of the UE comprises;

determining the uplink transmission power of the UE in a sub-frame i of a cell c according to the following formula,

3. The method of claim 1,

wherein determining the maximum transmission power allowed in the current sub-frame comprises:

determining, according to the control information including the UL-Grant, the maximum transmission power allowed of the UE as P_m,UE,c(i), and

wherein the determining the uplink transmission power of the UE comprises;

determining the uplink transmission power of the UE in a sub-frame i of a cell c according to the following formula,

4. The method of claim 1, wherein determining the maximum transmission power allowed in the current sub-frame, and determining the uplink transmission power of the UE comprises:

determining, by the UE, according to the control information including the UL-Grant, the uplink transmission power P_PUSCH,c(i) in sub-frame i of a cell c and the maximum power spectral density Power Spectral Density (PSD) allowed D_m,UE,c(i) of the UE; and

transmitting, by the UE, uplink signals according to the uplink transmission power P_PUSCH,c(i) when the PSD of the uplink transmission using P_PUSCH,c(i) is smaller than or is equal to D_m,UE,c(i); and

otherwise, reducing, by the UE, the uplink transmission power till the PSD of the uplink transmission is smaller than or is equal to D_m,UE,c(i).

5. The method of claim 1, wherein performing the uplink data transmission according to the uplink transmission power determined after the LBT is successful comprises at least one of the following:

for CAT2 and CAT4, starting the power increase transition time of the UE following the last CCA time slot of the LBT operation immediately;

or

for NO LBT, deferring T3 us after the ending of a downlink transmission, taking such a moment as the start timing of the power increase transition time of the UE, wherein T3 is the length of the deferred time.

6. The method of claim 5, wherein the LBT comprises:

for CAT4, occupying, by the UE, the channel only when CAT4 detection is finished before a moment t;

for CAT2, occupying, by the UE, the channel only when the channel is detected as idle for T1 us before the moment t;

for NO LBT, the length of period between the moment t and the ending of the downlink transmission is T3 us, wherein the start timing of the uplink transmission scheduled by a base station is t;

or

for CAT4, occupying, by the UE, the channel only when CAT4 detection is finished before moment t−

Tt;

for CAT2, occupying, by the UE, the channel only when the channel is detected as idle for T1 us before the moment t−

Tt;

for NO LBT, the length of period between the moment t−

Tt and the ending of a downlink transmission is T3 us, wherein the start timing of the uplink transmission scheduled by a base station is t, and the power increase transition time of the UE is Tt.

7. The method of claim 1, wherein performing the uplink data transmission according to the uplink transmission power determined in case that the LBT is successful comprises at least one of the following:

for CAT2 and CAT4, the last CCA time slot of the LBT of the UE comprising the power increase transition time of the UE;

or

for NO LBT, a later part of the T3 us time period after the ending of a downlink transmission comprising the power increase transition time of the UE.

8. The method of claim 1, wherein performing the uplink data transmission according to the uplink transmission power determined after the LBT is successful comprises at least one of the following:

for CAT2 and CAT4, the last CCA time slot of the LBT of the UE comprising a first part of the power increase transition time of the UE;

or

for NO LBT, a later part of the T3 us time period after the ending of a downlink transmission comprises the first part of the power increase transition time of the UE.

9. The method of claim 8, wherein the LBT comprises:

for CAT4, occupying, by the UE, the channel only when CAT4 detection is finished before moment t−

Tr;

for CAT2, occupying, by the UE, the channel only when the channel is detected as idle for T1 us before the moment t−

Tr;

for NO LBT, occupying, by the UE, the channel after a time period of T3 us from the ending of the downlink transmission, wherein the start timing of the uplink transmission scheduled by a base station is t, and the residual time of the power increase transition time between the LBT ending moment and the start timing of the uplink transmission scheduled by the base station is Tr;

or

for CAT4, occupying, by the UE, the channel only when CAT4 detection is finished before moment t;

for CAT2, occupying, by the UE, the channel only when the channel is detected as idle for T1 us before the moment t;

for NO LBT, occupying, by the UE, the channel after a time period of T3 us from the ending of the downlink transmission, wherein the start timing of the uplink transmission scheduled by the base station is t, and a last part of the power increase transition time of the UE is the moment t.

10. The method of claim 1, wherein performing the uplink data transmission comprises:

in a time period of Tb after starting of a power decrease transition time of the UE, reducing a transmission power of the UE to be below a certain strength Pb, wherein Tb and Pb are selected so that the channel is to be detected as idle by other devices nearby after the power decrease transition time of one device starts.

11. The method of claim 1, wherein performing the uplink data transmission according to the uplink transmission power determined after the LBT is successful comprises:

at T1+x us after the start timing of OFDM symbol 0 of the sub-frame, performing, by the UE, the uplink data transmission according to the uplink transmission power determined, wherein T1 is a channel idle time required by CAT2, and x is a predetermined value or a value configured by higher layer signaling;

or

at T1+TA+z us after the start timing of OFDM symbol 0 of the sub-frame, performing, by the UE, the uplink data transmission according to the uplink transmission power determined, wherein T1 is a channel idle time required by CAT2, TA is a time advancement of the UE, and z is a predetermined value or a value configured by higher layer signaling.

12. A base station for transmitting uplink information, the base station comprising:

a transceiver; and

a controller coupled with the transceiver and configured to control to;

transmit, to a user equipment (UE), control information including uplink (UL)-Grant for scheduling uplink data transmissions, and

receive, from the UE, an uplink data transmission according to an increased uplink transmission power, in case that the LBT is successful,

wherein a maximum transmission power allowed in a current sub-frame according to the control information including the UL-Grant is determined by the UE,

wherein the uplink transmission power of the UE is determined,

wherein listen before talk (LBT) according to the UL-Grant is executed by the UE, and

wherein the uplink transmission power of the UE to a certain strength Pa in a time period of Ta after a power increase transition time starts is increased by the UE in case that the LBT is successful, wherein Ta and Pa are selected so that a channel is to be detected as busy by other devices nearby after the power increase transition time of a device starts.

13. A user equipment (UE) for transmitting uplink information, the UE comprising:

a transceiver; and

a controller coupled with the transceiver and configured to control to;

detect control information including uplink (UL)-Grant for scheduling uplink data transmissions,

determine a maximum transmission power allowed in a current sub-frame according to the control information including the UL-Grant,

determine an uplink transmission power of the UE,

execute listen before talk (LBT) according to the UL-Grant,

increase the uplink transmission power of the UE to a certain strength Pa in a time period of Ta after a power increase transition time starts, wherein Ta and Pa are selected so that a channel is to be detected as busy by other devices nearby after the power increase transition time of a device starts, in case that the LBT is successful, and

perform an uplink data transmission according to the increased uplink transmission power, in case that the LBT is successful.