Techniques to support independent power control of multiple channels in CDMA systems (e.g., a W-CDMA system) that define a single power control feedback steam on the uplink, which is to be used for downlink power control. In one aspect, the single feedback stream is 'time shared' among multiple channels requiring individual power control. Various time-sharing schemes may be used to implement multiple (substantially parallel) feedback substreams based on the single feedback stream, and different combination of feedback rates may also be achieved for the substreams. Each feedback substream may be assigned to, and used for power control of, a respective channel. In another aspect, multiple feedback substreams are implemented based on multiple fields in newly defined slot formats.