A transmitting apparatus for transmitting signals in a multi carrier system on the basis of a frame structure, each frame comprising at least two preamble patterns adjacent to each other in the frequency direction and at least two data patterns, said transmitting apparatus comprising a pilot mapper configured to map the same sequence of pilot signals on frequency carriers of each of said at least two preamble patterns in a frame, each preamble pattern having the same length, a data mapper configured to map data on frequency carriers of said at least two data patterns in a frame, a transformer configured to transform said preamble patterns and said data patterns from the frequency domain into the time domain in order to generate a time domain transmission signal, and a transmitter configured to transmit said transmission signal.