A wireless device receives parameters of a configured periodic grant. The parameters indicate: a timing offset and a symbol number; a first periodicity indicating a time interval between two subsequent resources; and demodulation reference signal parameters. One or more symbols of a resource of the configured periodic grant are determining based on the timing offset, the symbol number, and the first periodicity. One or more transport blocks are transmitted, via the resource of the configured periodic grant, employing the demodulation reference signal parameters.