METHOD OF ALLOCATING REFERENCE SIGNALS IN MIMO SYSTEM

• US 20100103949A1
• Filed: 10/11/2007
• Published: 04/29/2010
• Est. Priority Date: 10/12/2006
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Jae Wan, Jung, Jin Hyuk, Ko, Hyun Soo, Ihm, Bin Chul, Chun, Jin Young
• Granted Patent: US 7,929,417 B2
• Time in Patent Office: Days
• US Class Current: 370/468
• CPC Class Codes: H04B 7/0447 utilizing uniform distribution
• CPC Class Codes: H04B 7/0697 using spatial multiplexing
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 25/0228 with direct estimation from sounding signals
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2655 Synchronisation arrangements
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver

Abstract

There is provided a method of allocating reference signals in a multiple-input multiple-output (MIMO) system. The method includes allocating a first reference signal, a second reference signal and a third reference signal in a first OFDM symbol so that the first reference signal, the second reference signal and the third reference signal do not overlap with each other and allocating the first reference signal, the second reference signal and a fourth reference signal in a second OFDM symbol so that the first reference signal, the second reference signal and the fourth reference signal do not overlap with each other. The first reference signal and the second signal are allocated in a regular intervals in a single OFDM symbol.

Claims

1. A method of allocating reference signals in a multiple-input multiple-output (MIMO) system, the reference signals allocated over a plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols and a plurality of subcarriers, the method comprising:

allocating a first reference signal, a second reference signal and a third reference signal in a first OFDM symbol so that the first reference signal, the second reference signal and the third reference signal do not overlap with each other; and

allocating the first reference signal, the second reference signal and a fourth reference signal in a second OFDM symbol, wherein the first reference signal and the second signal are allocated in a regular intervals in a single OFDM symbol.

2. The method of claim 1, wherein in the first OFDM symbol a null symbol is allocated to a subcarrier on which any one of the first reference signal, the second reference signal and the third reference signal is not allocated.

3. The method of claim 1, wherein in the second OFDM symbol a null symbol is allocated to a subcarrier on which any one of the first reference signal, the second reference signal and the fourth reference signal is not allocated.

4. The method of claim 1, wherein all transmit powers for the first reference signal, the second reference signal and the third reference signal are the same in the first OFDM symbol.

5. A method of allocating reference signals in a MIMO system, the reference signals allocated over a plurality of OFDM symbols and a plurality of subcarriers, the method comprising:

allocating a first reference signal for a first antenna and a second reference signal for a second antenna to two OFDM symbols, the two OFDM symbols which are separated from each other; and

allocating a third reference signal for a third antenna and a fourth reference signal for a fourth antenna to one of the two OFDM symbols, respectively.

6. The method of claim 5, wherein transmit powers of a plurality of antennas used for transmitting the reference signals is the same on a single OFDM symbol.

7. The method of claim 5, wherein a null symbol is allocated to a subcarrier on which any one of the reference signals is not allocated in the two OFDM symbols.