RANDOM ACCESS METHOD AND APPARATUS FOR USE IN WIRELESS COMMUNICATION SYSTEM SUPPORTING DUAL CONNECTIVITY

• US 20180184478A1
• Filed: 02/02/2018
• Published: 06/28/2018
• Est. Priority Date: 03/21/2014
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: JANG, Jaehyuk, KIM, Soenghun, VAN LIESHOUT, Gert-Jan, KIM, Youngbum
• Granted Patent: US 10,485,045 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
• CPC Class Codes: H04W 52/30 using constraints in the total amount of available transmission power
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 52/36 with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 52/365 Power headroom reporting
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 52/48 during retransmission after error or non-acknowledgment
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 76/15 Setup of multiple wireless link connections

Abstract

A random access method and an apparatus of a terminal for performing random access procedure to multiple base stations in parallel in a Long Term Evolution (LTE) system supporting dual connectivity are provided. The method includes determining whether a first preamble transmission to a first cell of a first base station is overlapped with a second preamble transmission to a second cell of a second base station in a time domain, determining, when the first preamble transmission is overlapped with the second preamble transmission in the time domain, whether a sum of transmit powers calculated for the first and second preamble transmissions is greater than a maximum allowed transmit power of the terminal, and controlling, when the sum of the first and second preamble transmit powers is greater than the maximum allowed transmit power, the transmit power calculated for the second preamble transmission.

Claims

1. A method by a terminal communicating with a master base station and a secondary base station, the method comprising:

identifying that a transmission of a first preamble on a primary cell of the master base station is overlapped with a transmission of a second preamble on a secondary cell of the secondary base station in a time domain and a sum of transmission powers determined for the transmissions of the first preamble and the second preamble is greater than a maximum allowed transmission power of the terminal;

transmitting the first preamble on the primary cell based on the transmission power determined for the transmission of the first preamble;

adjusting the transmission power determined for the transmission of the second preamble;

transmitting the second preamble on the secondary cell based on the adjusted transmission power; and

if no random access response is received within a predetermined period, skipping an increase of a number of transmission of the second preamble and retransmitting the second preamble at a transmission power determined based on the number of trans mission of the second preamble.