Access terminals are adapted to facilitate closed-loop transmit diversity in wireless communications systems. According to one example, an access terminal can calculate an uplink error rate for even slot indexes and a separate uplink error rate for odd slot indexes in an uplink frame to be transmitted. A respective downlink error rate can be estimated for an in-phase (I) component and a quadrature-phase (Q) component of a downlink transmission. The access terminal may further estimate a phase-related weight that was applied to the downlink transmission based on the downlink error rates and the uplink error rates. Other aspects, embodiments, and features are also included.