Method for sending preamble sequence and user equipment

Patent metadata

Field	Value
Publication number	US-2016234787-A1
Application number	US-201615018348-A
Country	US
Kind code	A1
Filing date	Feb 8, 2016
Priority date	Aug 13, 2013
Publication date	Aug 11, 2016
Grant date	—

Abstract

The present invention discloses a method for sending a preamble sequence and user equipment. The method includes: determining a transmit power for sending a preamble sequence, where the transmit power meets the following formula: Power=min{Pmax,PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL}, where Power is the determined transmit power, Pmax is a maximum transmit power of user equipment, PL is obtained by estimating according to a downlink path loss, and PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter is a target receive power of the preamble sequence, where PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter =preambleInitialReceivedTargetPower+DELTA_PREAMBLE−X i +(preamble_transmission_counter−1)*powerRampingStep; and preambleInitialReceivedTargetPower is an initial target receive power of the preamble sequence, DELTA_PREAMBLE is a power offset based on a format of the preamble sequence, powerRampingStep is a power ramp step, preamble_transmission_counter is a repetition count for transmitting the preamble sequence, and X i is a power offset corresponding to a preamble sequence resource pool i for coverage enhancement random access; and sending the preamble sequence according to the determined transmit power.

First claim

What is claimed is:

1 . A method for sending a preamble sequence, the method comprising:
determining a transmit power for sending a preamble sequence, wherein the transmit power meets the following formula:
Power=min{ P max,PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL}, wherein
Power is the determined transmit power, Pmax is a maximum transmit power of user equipment, PL is obtained by estimating according to a downlink path loss, and PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter is a target receive power of the preamble sequence, wherein
PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter =preambleInitialReceivedTargetPower+DELTA_PREAMBLE− X i +(preamble_transmission_counter−1)*powerRampingStep, and

preambleInitialReceivedTargetPower is an initial target receive power of the preamble sequence, DELTA_PREAMBLE is a power offset based on a format of the preamble sequence, powerRampingStep is a power ramp step, preamble_transmission_counter is a retransmission count of the preamble sequence, and X i is a power offset corresponding to a preamble sequence resource pool i for coverage enhancement random access; and sending the preamble sequence according to the determined transmit power.

2 . The method according to claim 1 , wherein the power offset X i meets
PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL−Pmax≦Δ, wherein Δ≧0, and Δ is a constant and a preset threshold.

3 . The method according to claim 2 , further comprising:
determining the power offset X i , wherein determining the power offset X i comprises:
searching for the power offset X i in ascending order of power offsets, or searching for the power offset X i in ascending order of repetition counts for transmitting the preamble sequence.

4 . The method according to claim 2 , wherein sending the preamble sequence comprises:
transmitting the preamble sequence by using a repetition count corresponding to the preamble sequence resource pool i for coverage enhancement random access.

5 . The method according to claim 2 , wherein the determined transmit power is PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL.

6 . The method according to claim 2 , wherein the power offset X i is a coverage enhancement amount that is corresponding to the repetition count corresponding to the preamble sequence resource pool i for coverage enhancement random access.

7 . The method according to claim 2 , wherein determining a transmit power for sending a preamble sequence comprises:
obtaining PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter by performing calculation according to the power offset X i , and sending the preamble sequence according to PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter , to perform the preamble_transmission_counter th random access; if the preamble_transmission_counter th random access fails, increasing preamble_transmission_counter by one, keeping X i unchanged, and calculating the following again: RECEIVED_TARGET_POWER i preamble _ transmission _ counter ; and if a condition that PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL−Pmax≦Δ is met, performing transmission by using the repetition count corresponding to the preamble sequence resource pool i for coverage enhancement random access, wherein the transmit power is PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL; or if a condition that PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL−Pmax≦Δ is not met, searching for the power offset X i in ascending order of repetition counts or the power offsets X i , and determining whether the found power offset X i meets PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL−Pmax≦Δ; and if a minimum value of X i that meets the foregoing formula is found, performing transmission by using the repetition count corresponding to the preamble sequence resource pool i for coverage enhancement random access, wherein the transmit power is PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL; or if the foregoing inequality cannot be met after all X i are traversed, performing transmission by using a repetition count corresponding to a preamble sequence resource pool i for coverage enhancement random access that is found at last, wherein the transmit power is Pmax.

8 . The method according to claim 1 , wherein information about the preamble sequence resource pool i for coverage enhancement random access is obtained from system information or is preset.

9 . The method according to claim 8 , wherein the information about the preamble sequence resource pool i for coverage enhancement random access comprises at least one type of the following information:
the repetition count corresponding to the preamble sequence resource pool i for coverage enhancement random access and a coverage enhancement amount corresponding to the preamble sequence resource pool i for coverage enhancement random access.

10 . User equipment, comprising:
a processor configured to execute the following operation by invoking an operation instruction:
determining a transmit power for sending a preamble sequence, wherein the transmit power meets the following formula:
Power=min{ P max,PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL},

wherein Power is the determined transmit power, Pmax is a maximum transmit power of the user equipment, PL is obtained by estimating according to a downlink path loss, and PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter is a target receive power of the preamble sequence, wherein
PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter =preambleInitialReceivedTargetPower+DELTA_PREAMBLE− X i +(preamble_transmission_counter−1)*powerRampingStep, and

preambleInitialReceivedTargetPower is an initial target receive power of the preamble sequence, DELTA_PREAMBLE is a power offset based on a format of the preamble sequence, powerRampingStep is a power ramp step, power_transmission_counter is a repetition count for transmitting the preamble sequence, and X i is a power offset corresponding to a preamble sequence resource pool i for coverage enhancement random access; and
a sender configured to send the preamble sequence according to the determined transmit power.

11 . The user equipment according to claim 10 , wherein the power offset X i meets:
PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL−Pmax≦Δ, wherein Δ≧0, and Δ is a constant and a preset threshold.

12 . The user equipment according to claim 11 , wherein the processor is further configured to:
search for the power offset X i in ascending order of power offsets; or search for the power offset X i in ascending order of repetition counts for transmitting the preamble sequence.

13 . The user equipment according to claim 11 , wherein the sender is further configured to transmit the preamble sequence by using a repetition count corresponding to the preamble sequence resource pool i for coverage enhancement random access.

14 . The user equipment according to claim 11 , wherein the determined transmit power is:
PREAMBLE_RECEIVED_TARGET_POWER i preamble _ transmission _ counter +PL.

15 . The user equipment according to claim 11 , wherein the power offset X i

Assignees

• Huawei Tech Co Ltd

Inventors

• Liu Deping

Classifications

• H04W52/325

  Power control of control or pilot channels · CPC title

• H04W52/50

  at the moment of starting communication in a multiple access environment · CPC title

• H04W52/367 Primary

  Power values between minimum and maximum limits, e.g. dynamic range · CPC title

• H04W52/28

  using user profile, e.g. mobile speed, priority or network state, e.g. standby, idle or non-transmission · CPC title

• H04W52/242

  taking into account path loss · CPC title