Apparatus and method for transmitting/receiving a pilot sequence in a mobile communication system using space-time trellis code

An apparatus for transmitting a sequence for channel estimation through M transmission antennas in a mobile communication system, the apparatus comprising:

• a sequence generator for generating the sequence for the channel estimation;
• P encoders for receiving P information bit streams and encoding the received P information bit streams with a space-time trellis code (STTC);
• M modulators for modulating information bit streams encoded from the P encoders as a punctured code into modulation symbol streams respectively;
• M puncturers for puncturing at least one modulation symbol in a predetermined position at each transmission antenna for each of the modulation symbol streams output from the M modulators;
• and
• M multiplexers individually connected to the M transmission antennas, for multiplexing each of the punctured signals output from the M puncturers and the sequence to be inserted in the predetermined position,
• wherein at least one of puncturing positions for the modulation symbol streams is different from other puncturing positions at each antenna in a same transmission period.