Transmit and/or receive diversity is achieved using multiple antennas. In
some embodiments, a single transmitter chain within a wireless terminal is coupled
over time to a plurality of transmit antennas. At any given time, a controllable
switching module couples the single transmitter chain to one the plurality of transmit
antennas. Over time, the switching module couples the output signals from the single
transmitter chain to different transmit antennas. Switching decisions are based
upon predetermined information, dwell information, and/or channel condition feedback
information. Switching is performed on some dwell and/or channel estimation boundaries.
In some OFDM embodiments, each of multiple transmitter chains is coupled respectively
to a different transmit antenna. Information to be transmitted is mapped to a plurality
of tones. Different subsets of tones are formed for and transmitted through different
transmit chain/antenna sets simultaneously. The balance of tones allocated to the
subsets for each antenna are changed as a function of predetermined information,
dwell information, and/or channel condition feedback information.