Methods, systems, and devices for wireless communications are described. In some wireless communications systems, a wireless device may broadcast a discovery preamble to identify a receiving device or to identify a suitable beam for communicating with a receiving device prior to broadcasting a discovery message to the receiving device. In such systems, the wireless device may use the techniques described herein to generate the discovery preamble and to reduce interference between discovery preamble transmissions and avoid data loss. In one example, a wireless device may append a cyclic prefix (CP) to a discovery preamble with a suitable length to protect the discovery preamble from interference from another transmission. In another example, the wireless device may generate a cyclically periodic signal including multiple copies of the discovery preamble so a receiving device may be able to receive a portion of the signal and identify the discovery preamble.