Large delay cyclic delay diversity (CDD) precoder for open loop multiple-input multiple-output (MIMO)
A physical channel processor on a wireless device and method for precoding for spatial multiplexing in an open-loop multiple-input multiple-output (MIMO) mobile communication system is disclosed. The method comprises the operation of receiving an input vector block from a layer mapper. The input vector block includes user equipment-specific reference signals (UE-RSs) or data in a physical downlink shared channel (PDSCH). The operation of generating a large delay cyclic delay diversity (CDD) vector block from the input vector block using a precoder configured for large delay CDD on an antenna port follows. The data can be resource element mapped with UE-RSs or channel-state information reference signals (CSI-RSs) in a physical resource block (PRB).
1. A method for precoding for spatial multiplexing in an open-loop multiple-input multiple-output (MIMO) mobile communication system, comprising:
receiving an input vector block from a layer mapper, wherein the input vector block includes user equipment-specific reference signals (UE-RSs) or data in a physical downlink shared channel (PDSCH); and
generating a large delay cyclic delay diversity (CDD) vector block from the input vector block using a precoder configured for large delay CDD on an antenna port, wherein the data is resource element mapped with UE-RSs or channel-state information reference signals (CSI-RSs) in a physical resource block (PRB).
2. The method of claim 1 , wherein the large delay CDD vector block has a rank greater than four.
3. The method of claim 1 , wherein the precoder includes a precoding matrix predefined in a codebook on a wireless device.
4. The method of claim 1 , wherein the precoder for the UE-RS or data in the PDSCH uses a precoding matrix W.
5. The method of claim 4 , wherein the precoding matrix W is a random beam forming matrix.
6. The method of claim 1 , wherein the precoder for data in the PDSCH uses a matrix product of a precoding matrix W, a diagonal large delay CDD matrix D, and a rotation matrix U.
7. The method of claim 6 , wherein the diagonal large delay CDD matrix D and the rotation matrix U are predefined based on a number of layers.
8. The method of claim 1 , wherein the precoder includes a precoding matrix configured to change from PRB to PRB.
9. The method of claim 1 , further comprising:
transmitting the large delay CDD vector block to a resource element mapper; and
mapping the large delay CDD vector block by the resource element mapper in a PRB, wherein the data in the PDSCH is mapped with UE-RSs or CSI-RSs when the large delay CDD vector block includes data in the PDSCH.
10. The method of claim 1 , wherein the precoding for UE-RSs or data in the PDSCH is defined by
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is the large delay cyclic delay diversity (CDD) vector block, W(i) is a precoding matrix of size P×v where P is a number of antenna ports used for transmission of a channel and v is a number of transmission layers, and i=0, 1, . . . , M symb ap −1, M symb ap =M symb layer where M symb ap is a number of modulation symbols to transmit per antenna port for a physical channel and M symb layer is a number of modulation symbols to transmit per antenna port for a physical channel.
11. The method of claim 1 , wherein the precoding for spatial multiplexing using antenna ports for data in the PDSCH is defined by
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is the large delay cyclic delay diversity (CDD) vector block, D(i) is a diagonal large delay cyclic delay diversity (CDD) matrix of size v×v, U is a rotation matrix of size v×v, W(i) is a precoding matrix of size P×v where P is a number of antenna ports used for transmission of a channel and v is a number of transmission layers, and i=0, 1, . . . , M symb ap −1, M symb ap =M symb layer where M symb ap is a number of modulation symbols to transmit per antenna port for a physical channel and M symb layer is a number of modulation symbols to transmit per antenna port for a physical channel.
12. The method of claim 1 , further comprising transmitting a transmission mode using a cell radio network temporary identifier (C-RNTI) to configure a user equipment (UE) for large delay CDD decoding of the PDSCH.
13. The method of claim 1 , further comprising receiving a physical uplink shared channel (PUSCH) feedback including a channel quality indicator (CQI) or a transmission rank indicator (RI) without a precoding matrix indicator (PMI).
14. The method of claim 13 , wherein receiving the PUSCH feedback includes at least two CQIs generated from at least two transport blocks.
15. A physical channel processor on a wireless device, comprising:
a precoder configured for large delay CDD on an antenna port, wherein the precoder generates a large delay cyclic delay diversity (CDD) vector block from an input vector block, the input vector block includes user equipment-specific reference signals (UE-RSs) or data in a physical downlink shared channel (PDSCH), and the the data is resource element mapped with UE-RSs or channel-state information reference signals (CSI-RSs) in a physical resource block (PRB).
16. The physical channel processor of claim 15 , further comprising a layer mapper for generating input vector block.
17. The physical channel processor of claim 15 , further comprising a resource element mapper for mapping the large delay CDD vector block in a PRB, wherein the data in the PDSCH is mapped with UE-RSs or CSI-RSs when the large delay CDD vector block includes data in the PDSCH.
18. The physical channel processor of claim 15 , wherein the precoder is configured for large delay CDD transmitted on up to eight antennas.
19. The physical channel processor of claim 15 , wherein the large delay CDD vector block has a rank greater than four.
20. The physical channel processor of claim 15 , wherein the precoder includes a precoding matrix predefined in a codebook on the wireless device.
21. The physical channel processor of claim 15 , further comprising a transceiver for transmitting a transmission mode using a cell radio network temporary identifier (C-RNTI) to configure a user equipment (UE) for large delay CDD decoding of the PDSCH.
22. The physical channel processor of claim 15 , further comprising a transceiver for receiving a physical uplink shared channel (PUSCH) feedback including a channel quality indicator (CQI) or a transmission rank indicator (RI) without a precoding matrix indicator (PMI).
23. The physical channel processor of claim 15 , wherein the physical channel processor is included in a wireless device configured to connect to at least one of a wireless local area network (WLAN), a wireless personal area network (WPAN), and a wireless wide area network (WWAN), wherein the wireless device includes an antenna, a touch sensitive display screen, a speaker, a microphone, a graphics processor, an application processor, internal memory, a non-volatile memory port, or combinations thereof.
24. A computer program product, comprising a non-transitory computer usable medium having a computer readable program code embodied therein, the computer readable program code adapted to be executed to implement a method for precoding for spatial multiplexing in an open-loop multiple-input and multiple-output (MIMO) mobile communication system comprising:
receiving an input vector block from a layer mapper, wherein the input vector block includes user equipment-specific reference signals (UE-RSs) or data in a physical downlink shared channel (PDSCH); and
generating a large delay cyclic delay diversity (CDD) vector block from the input vector block using a precoder configured for large delay CDD on an antenna port, wherein the data is resource element mapped with UE-RSs or channel-state information reference signals (CSI-RSs) in a physical resource block (PRB).
25. The computer program product of claim 24 , wherein the large delay CDD vector block has a rank greater than four.