Techniques for supporting communication with carrier extension are described. In one design, a base carrier and at least one segment available to a user equipment (UE) for communication may be determined. At least one operating parameter for the UE may be determined based on a composite bandwidth of the base carrier and the at least one segment. The UE may communicate based on the at least one operating parameter, which may include a resource block group (RBG) size and/or a bitmap used for resource allocation on the downlink, a gap used for resource allocation with frequency hopping on the downlink, a number of hopping bits used for resource allocation with frequency hopping on the uplink, a subband size and/or a number of bandwidth parts used for channel quality indicator (CQI) reporting, a sounding reference signal (SRS) bandwidth and/or a SRS configuration for SRS transmission on the uplink, and/or other operating parameters.