Techniques for sending control information in a wireless communication system are described. In an aspect, a user equipment (UE) may send data for control information in a resource block with frequency division multiplexing (FDM) and may send pilot in the resource block with frequency-domain code division multiplexing (CDM). The UE may determine multiple groups of subcarriers to use to send data in multiple symbol periods of the resource block based on a predetermined pattern or a pseudo-random hopping pattern. Each group may include consecutive subcarriers to support localized FDM. The multiple groups may include different subcarriers to provide frequency diversity and possibly interference averaging. The UE may send modulation symbols for data (e.g., in the time domain) on the multiple groups of subcarriers in the multiple symbol periods. The UE may send a reference signal sequence for pilot on multiple subcarriers in each symbol period for pilot.