The present invention relates to a transmit unit, a control unit and a method in a transmit unit comprising at least two antennas for transmitting signals relating to a plurality of radio channels. The transmit unit transmit signals relating to a first subset of channels from the first antenna and pilot signals from the first antenna for use a reference for the first subset of channels. The transmit unit is further arranged to transmit signals relating to a second subset of channels from the second antenna using single antenna transmission. The transmit unit also transmits pilot signals on a second type of pilot channel such as the S-CPICH, different from the first type of pilot channel, from the second antenna for use as a reference for the second subset of channels, wherein the first and second type of pilot channels are substantially covering the same area.