METHOD FOR ALLOCATING PHICH AND GENERATING REFERENCE SIGNAL IN SYSTEM USING SINGLE-USER MIMO BASED ON MULTIPLE CODEWORDS WHEN TRANSMITTING UPLINK

• US 20110176502A1
• Filed: 07/22/2009
• Published: 07/21/2011
• Est. Priority Date: 07/22/2008
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Ko, Hyun Soo, Han, Seung Hee, Lee, Moon II, Kwon, Yeong Hyeon, Chung, Jae Hoon, Kim, So Yeon
• Granted Patent: US 8,503,425 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1861 Physical mapping arrangements for ACK signaling see also H04L5/0053
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0026 Division using four or more dimensions
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network

Abstract

The present invention relates to a method for generating an uplink reference signal in a system supporting plural uplink-access transmission modes. The method comprises: a step for transmitting the reference signal configuration information about the configuration of a reference signal from a base station to a user device through an uplink grant PDCCH (Physical Downlink Control Channel), and a step for receiving from the user device a sub-frame including the reference signal that is generated based on the reference signal configuration information. The reference signal configuration information is prepared for plural uplink access transmission modes and includes a cyclic shift value for the sequence of the reference signal. The reference signal is supposed to be transmitted to an uplink, and the user device is set up to be operated in the uplink-access transmission mode that corresponding to the reference signal configuration information.

Claims

1. A method of generating an uplink reference signal in a Single-User Multiple Input Multiple Output (SU-MIMO) system for transmitting one or more codewords in uplink, the method comprising:

transmitting, at a base station, reference signal configuration information indicating the configuration of reference signals to be transmitted in uplink to a user equipment through a uplink grant Physical Downlink Control Channel (PDCCH), wherein the user equipment is set to operate according to an uplink access mode corresponding to the information; and

receiving a subframe including the reference signals generated based on the reference signal configuration information from the user equipment,

wherein the reference signal configuration information includes cyclic shift values of sequences of the reference signals.

2. The method according to claim 1, wherein the reference signal configuration information includes information about cyclic shifts of N (N≦

M) reference signals among all M reference signals to be transmitted in uplink, and the information includes cyclic shift index of a reference signal used as a criterion among the N reference signals and offset information for determining cyclic shift indexes of remaining N−

1 reference signals.

3. The method according to claim 1, wherein the reference signal configuration information includes cyclic shift indexes of N (N≦

M) reference signals among all M reference signals to be transmitted in uplink.

4. The method according to claim 2 or 3, wherein the N reference signals are Constant Amplitude Zero Autocorrelaton (CAZAC) reference signals.

5. The method according to claim 2 or 3, wherein the N reference signals of the M reference signals are inserted at predetermined symbol positions of a time domain and are subjected to a Discrete Fourier Transform (DFT) process.

6. The method according to claim 2 or 3, wherein the N reference signals of the M reference signals are directly mapped to sample points corresponding to an allocated frequency transmission band at an input end of Inverse Discrete Fourier Transform (IDFT) or Inverse Fast Fourier Transform (IFFT).

7. The method according to claim 1, wherein the value M is determined according to a number of physical transmission antennas, physical transmission antennas or transmission layers of a subframe configured in the user equipment.

8. A method of allocating a Physical Hybrid automatic repeat request Indicator Channel (PHICH) for transmitting ACKnowledgement/Negative ACKnowledgement (ACK/NACK) with respect to each transmitted codeword in a Single-User Multiple Input Multiple Output (SU-MIMO) system for transmitting one or more codewords in uplink, the method comprising:

determining a number of PHICH groups; and

determining a PHICH group index and an orthogonal sequence index within the PHICH group using the number of PHICH groups,

wherein the number of PHICH groups is determined using a maximum number of codewords upon uplink transmission.

9. The method according to claim 8, wherein the PHICH group index and the orthogonal sequence index within the PHICH group are determined using a function for providing a unique offset value of each codeword.