Dynamic transmission antenna reconfiguration in wireless networks

1. A method of wireless communications implementable in a cellular network comprising a cell served by multiple antennas located at one or more base stations configured to provide wireless services to a wireless device in the cell, comprising:

configuring a first antenna group to include a first antenna from the multiple antennas located at the one or more base stations to transmit common system information, a common reference signal, and data according to a first format and a second format to the wireless device in the cell;

configuring a second antenna group to include a second antenna different from the first antenna to transmit data according to the second format, without transmitting common system information or common reference signals, to the wireless device in the cell; and

dynamically assigning, based on a network operational status, antennas from the multiple antennas located at the one or more base stations to either the first antenna group or the second antenna group.

2. The method recited in claim 1 , further comprising:

using one or more antennas of a macro base station in the cell as the first antenna group to provide wireless coverage to a macrocell covered by the macro base station; and

using one or more antennas of a micro base station in the cell operating at a power level lower than the macro base station as the second antenna group to provide wireless coverage to a microcell that occupies a smaller geographic area than the macrocell and overlaps at least partially with the macrocell.

3. The method recited in claim 1 , wherein the network operational status includes at least one of: whether or not legacy mobile stations incapable of using the second format are present in the microcell, data traffic load in the macrocell and data traffic load in the microcell.

4. The method recited in claim 1 , wherein the first format uses transmission parameters derived from a common reference signal and the second format uses transmission parameters derived from a dedicated reference signal.

5. The method recited in claim 1 , further comprising:

using one or more first antennas of a base station in the cell as the first antenna group to provide wireless coverage to the cell; and

using one or more second antennas from the base station in the cell as the second antenna group to provide wireless coverage to the cell.

6. A wireless communications apparatus, comprising:

a first antenna configurator that configures a first antenna group to include a first antenna from the multiple antennas located at one or more base stations to transmit common system information, a common reference signal, and data according to a first format and a second format to the wireless device in the cell;

a second antenna configurator that configures a second antenna group to include a second antenna different from the first antenna to transmit data according to the second format, without transmitting common system information or common reference signals, to the wireless device in the cell; and

a dynamic antenna assignor that dynamically assigns, based on a network operational status, antennas from the multiple antennas located at the one or more base stations to either the first antenna group or the second antenna group.

7. The apparatus recited in claim 6 , further including:

a macrocell controller that uses one or more antennas of a macro base station in the cell as the first antenna group to provide wireless coverage to a macrocell; and

a microcell controller that uses one or more antennas of a micro base station in the cell operating at a power level lower than the macro base station as the second antenna group to provide wireless coverage to a microcell that occupies a smaller geographic area than the macrocell and overlaps at least partially with the macrocell.

8. The apparatus recited in claim 6 , wherein the network operational status includes one of: whether or not legacy mobile stations incapable of using the second format are present in the microcell, data traffic load in the macrocell and data traffic load in the microcell.

9. The apparatus recited in claim 6 , wherein the first format uses transmission parameters derived from a common reference signal and the second format uses transmission parameters derived from a dedicated reference signal.

10. The apparatus recited in claim 6 , wherein:

the first configurator is further configured to use one or more first antennas of a base station in the cell as the first antenna group to provide wireless coverage to the cell; and

the second configurator is further configured to use one or more second antennas from the base station in the cell as the second antenna group to provide wireless coverage to the cell.