Ambiguity/Aliasing cancellation or reduction for staggered reference signals

An apparatus for a wireless communication system is described. The apparatus is to transmit a reference signal on a common set of resource elements, REs, the common set of REs used by one or more further apparatuses in the wireless communication system to transmit the reference signal so that the reference signals of the apparatus and of the one or more further apparatuses use the same REs. The apparatus is to transmit the reference signal using a plurality of OFDM symbols, each OFDM symbol having a comb structure, and some or all of the OFDM symbols having different comb offsets, and apply the same sequence to each OFDM symbol, the sequence having a zero auto correlation property, the apparatus and the one or more further apparatus using for a common RE the same sequence. The apparatus is to apply a phase correction to an OFDM symbol before transmission, wherein the phase correction is applied in the time domain or in the frequency domain by multiplying the ODFM symbol with a correction factor e<jfc>, and wherein the correction factor e<jfc> depends on the comb factor and the comb offset of the OFDM symbol and is independent of the resource element.