Methods, systems, and devices for wireless communication are described that support communication of information buts based on reference signal index modulation (RS-IM). A base station and a UE may transmit a number of downlink and uplink information bits (e.g., downlink control bits, uplink control bits) using index modulation schemes applied on references signals. A base station and a UE may transmit reference signal transmissions using reference signal index modulation, in which a set of information bits may be encoded using one or more coding techniques, in conjunction with RS-IM techniques, to enhance reliability of some or all of the information bits. Error detection bits may be added to the information bits, and included when coding is performed. Coding may include channel coding, repetition of reference signals for combining at a receiving device, or any combinations thereof.