A first wireless device receives, from a second wireless device and via a physical sidelink control channel (PSCCH), sidelink control information that includes a number of demodulation reference signal (DMRS) antenna ports and resource assignment of a physical shared channel (PSSCH) received in one or more first resources. The first wireless device determines a second reference signal received power (RSRP) of the PSSCH based on a measurement of a first RSRP of the PSSCH and at least one of: the number of DMRS antenna ports or measurement of a channel busy ratio (CBR). The first wireless device transmits, via one or more second resources selected based on the second RSRP and that are for transmission within a set of candidate resources, one or more transport blocks via the one or more second resources.