METHOD AND APPARATUS FOR MAPPING A PLURALITY OF LAYERS TO A PLURALITY OF ANTENNA PORTS IN A WIRELESS COMMUNICATION SYSTEM

• US 20130070732A1
• Filed: 02/21/2011
• Published: 03/21/2013
• Est. Priority Date: 02/19/2010
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Noh, Min Seok, Chung, Jae Hoon, Ko, Hyun Soo, Han, Seung Hee, Lee, Moon Il
• Granted Patent: US 8,923,250 B2
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 7/0473 taking constraints in layer or codeword to antenna mapping into account
• CPC Class Codes: H04J 13/18 Allocation of orthogonal codes
• CPC Class Codes: H04L 5/0016 Time-frequency-code
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• 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 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04L 5/0082 at predetermined intervals
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels

Abstract

Provided are a method and apparatus for allocating a plurality of layers to a plurality of antenna ports in a wireless communication system. The method comprises: mapping the plurality of layers to the respective antenna ports; and mapping demodulation reference signals (DMRS) of the plurality of layers to a first code division multiplexing (CDM) set or to a second CDM set, and transmitting the signals via the plurality of antenna ports.

Claims

1-15. -15. (canceled)

16. A method of allocating a plurality of layers to a plurality of antenna ports in a wireless communication system, the method comprising:

mapping the plurality of layers to the plurality of antenna port, respectively, and

mapping demodulation reference signals (DMRSs) of the plurality of layers to a first code division multiplexing (CDM) set or a second CDM set among radio resources and transmitting the DMRSs through the plurality of antenna ports,

wherein the DMRSs mapped to a first CDM set in a first resource block (RB), from among the DMRSs of the plurality of layers, are mapped to a second CDM set in a second RB different from the first RB, and

the DMRSs mapped to a second CDM set in the first RB, from among the DMRSs of the plurality of layers, are mapped to a first CDM set in the second RB different from the first RB.

17. The method of claim 16, wherein a number of the plurality of layers is an odd number.

18. The method of claim 16, wherein the DMRSs of the plurality of layers are mapped to a predetermined CDM set irrespective of a number of the plurality of layers.

19. The method of claim 16, wherein the first CDM set or the second CDM set is mapped to predetermined specific antenna ports of the plurality of antenna ports irrespective of the number of the plurality of layers.

20. The method of claim 19, wherein antenna ports mapped to the first CDM set and antenna ports mapped to the second CDM set are mutually exclusively.

21. The method of claim 16, wherein:

the first CDM set occupies a Resource Element (RE) allocated to first, sixth, and eleventh subcarriers of sixth and seventh Orthogonal Frequency Division Multiplexing (OFDM) symbols of each slot, and

the second CDM set occupies an RE allocated to second, seventh, and twelfth subcarriers of sixth and seventh OFDM symbols of each slot.

22. The method of claim 16, wherein a maximum of four layers in the first CDM set or the second CDM set are multiplexed according to a CDM method based on an orthogonal code.

23. The method of claim 22, wherein a length of the orthogonal code is 4.

24. The method of claim 16, wherein the DMRSs of the plurality of layers are transmitted with identical power.

25. An apparatus in a wireless communication system, comprising:

a radio frequency (RF) unit for transmitting demodulation reference signals (DMRSs) of a plurality of layers through a plurality of antenna ports; and

a processor connected to the RF unit,

wherein the processor is configured for;

mapping the plurality of layers to the plurality of antenna ports, respectively; and

mapping the DMRSs of the plurality of layers to a first code division multiplexing (CDM) set or a second CDM set of radio sources, and

wherein the DMRSs mapped to a first CDM set in a first resource block (RB), from among the DMRSs of the plurality of layers, are mapped to a second CDM set in a second RB different from the first RB, and

the DMRSs mapped to a second CDM set in the first RB, from among the DMRSs of the plurality of layers, are mapped to a first CDM set in the second RB different from the first RB.

26. The apparatus of claim 25, wherein a number of the plurality of layers is an odd number.

27. The apparatus of claim 25, wherein the DMRSs of the plurality of layers are mapped to a predetermined CDM set irrespective of a number of the plurality of layers.

28. The apparatus of claim 25, wherein the first CDM set or the second CDM set is mapped to predetermined specific antenna ports of the plurality of antenna ports irrespective of the number of the plurality of layers.