Systems and methodologies are described that facilitate employing downlink precoding based on uplink sounding channel measurement and channel reciprocity in time division duplex or time division multiplex systems. In particular, mechanism are provided that enable downlink precoding in situations where user equipment antenna configuration includes an unequal number of transmit chains and receive chains. A mobile device transmits modulated sounding reference signals on each antenna during a calibration stage. The mobile device then transmits non-modulated sounding reference signals during a normal mode. A base station utilizes the modulated and non-modulated sounding reference signals to restore a downlink channel estimate employed in downlink precoding.