Multi-cell signals in OFDM wireless networks
A wireless device receives control messages indicating CSI measurement resources of cells belonging to at least two base stations or belonging to at least two sectors of a base station. The wireless device measures CSI employing at least CSI measurement resources of the cells. The wireless device quantizes the measured CSI jointly across cells and encodes and transmits the jointly quantized CSI. The wireless device receives a resource assignment for data packet(s). The wireless device receives signals carrying the data packets from multiple cells.
1. A wireless device comprising:
a) one or more communication interfaces;
b) one or more processors; and
c) memory storing instructions that, when executed, cause said wireless device to:
i) receive from a first base station at least one control message indicating channel state information (CSI) measurement resources of a subset of cells, a CSI measurement resource corresponding to a plurality of resource elements in a plurality of subframes on an antenna port of a cell in said subset of cells, cells in said subset of cells belonging to at least two base stations comprising said first base station or belonging to at least two sectors of said first base station;
ii) measure CSI employing at least said CSI measurement resources of said subset of cells;
iii) quantize said measured CSI jointly across cells in said subset of cells;
iv) encode and transmit said jointly quantized CSI according to a physical uplink control channel format;
v) receive, from said first base station on one serving cell in said subset of cells, at least one resource assignment for at least one data packet; and
vi) simultaneously receive signals from multiple cells in said subset of cells, said signals carrying said at least one data packet for said wireless device, said multiple cells belonging to said at least two base stations or belonging to at least two sectors of said first base station.
2. The wireless device of claim 1 , wherein said CSI is represented by a matrix.
3. The wireless device of claim 1 , wherein said CSI is represented by a precoding matrix indicator.
4. The wireless device of claim 1 , wherein an instance of said CSI comprises a precoding matrix indicator calculated for said subset of cells.
5. The wireless device of claim 1 , wherein said at least one control message comprises:
a) a CSI reference signal subframe configuration parameter;
b) a CSI reference signal antenna port configuration parameter; and
c) a CSI reference signal radio resource configuration parameter.
6. The wireless device of claim 1 , wherein said at least one control message indicates a plurality of subframes for said CSI measurement.
7. The wireless device of claim 1 , wherein said CSI measurement resources determine sub-band or wideband CSI measurement, wherein said wideband CSI measurement corresponds to CSI measurement on a carrier bandwidth.
8. The wireless device of claim 1 , wherein said CSI measurement resources comprise reference signals in said sub-band or said wideband.
9. The wireless device of claim 7 , wherein a physical uplink control channel format determines whether any of the following measurements are comprised in said CSI:
a) a channel quality indicator (CQI);
b) a precoding matrix indicator (PMI);
c) a precoding type indicator (PTI); and
d) a rank indicator (RI).
10. A first base station comprising:
a) one or more communication interfaces;
b) one or more processors; and
c) memory storing instructions that, when executed, cause said first base station to:
i) transmit to a wireless device at least one control message indicating channel state information (CSI) measurement resources of a subset of cells, a CSI measurement resource corresponding to a plurality of resource elements in a plurality of subframes on an antenna port of a cell in said subset of cells, cells in said subset of cells belonging to at least two base stations comprising said first base station or belonging to at least two sectors of said first base station;
ii) receive and decode jointly quantized CSI according to a physical uplink control channel format, wherein CSI is measured employing at least said CSI measurement resources of said subset of cells, and said measured CSI is quantized jointly across cells in said subset of cells to generate said jointly quantized CSI;
iii) transmit, to said wireless device on one serving cell in said subset of cells, at least one resource assignment for at least one data packet; and
iv) transmit signals of said at least one data packet to said wireless device, said at least one data packet being transmitted employing multiple cells, said multiple cells belonging to said at least two base stations or belonging to at least two sectors of said first base station.
11. The first base station of claim 10 , wherein said at least one control message comprises:
a) a CSI reference signal subframe configuration parameter;
b) a CSI reference signal antenna port configuration parameter; and
c) a CSI reference signal radio resource configuration parameter.
12. The first base station of claim 10 , wherein said at least one control message indicates a plurality of subframes for said CSI measurement.
13. The first base station of claim 10 , wherein said CSI measurement resources determine sub-band or wideband CSI measurement, wherein said wideband CSI measurement corresponds to CSI measurement on a carrier bandwidth.
14. The first base station of claim 10 , wherein a physical uplink control channel format determines whether any of the following measurements are comprised in said CSI:
a) a channel quality indicator (CQI);
b) a precoding matrix indicator (PMI);
c) a precoding type indicator (PTI); and
d) a rank indicator (RI).
15. A wireless network comprising a subset of cells belonging to at least two base stations comprising a first base station or belonging to at least two sectors of said first base station, said wireless network configured to:
i) transmit, by said first base station to a wireless device, at least one control message indicating channel state information (CSI) measurement resources of said subset of cells, a CSI measurement resource corresponding to a plurality of resource elements in a plurality of subframes on an antenna port of a cell in said subset of cells;
ii) receive and decode jointly quantized CSI according to a physical uplink control channel format, wherein CSI is measured employing at least said CSI measurement resources of said subset of cells, and said measured CSI is quantized jointly across cells in said subset of cells to generate said jointly quantized CSI;
iii) transmit, by said first base station to said wireless device on one serving cell in said subset of cells, at least one resource assignment for at least one data packet; and
iv) simultaneously transmit signals from multiple cells in said subset of cells, said signals carrying said at least one data packet for said wireless device, said multiple cells belonging to said at least two base stations or belonging to at least two sectors of said first base station.
16. The wireless network of claim 15 , wherein an instance of said CSI comprises a precoding matrix indicator calculated for said subset of cells.
17. The wireless network of claim 15 , wherein said at least one control message comprises:
a) a CSI reference signal subframe configuration parameter;
b) a CSI reference signal antenna port configuration parameter; and
c) a CSI reference signal radio resource configuration parameter.
18. The wireless network of claim 15 , wherein said at least one control message indicates a plurality of subframes for said CSI measurement.
19. The wireless network of claim 15 , wherein said CSI measurement resources comprise reference signals in said sub-band or said wideband.
20. The wireless network of claim 15 , wherein a physical uplink control channel format determines whether any of the following measurements are comprised in said CSI:
a) a channel quality indicator (CQI);
b) a precoding matrix indicator (PMI);
c) a precoding type indicator (PTI); and
d) a rank indicator (RI).