1. A symbol-based processing method for downlink signals of a wireless communication device, the method comprising:receiving a first downlink signal comprising a plurality of symbols;
detecting a physical downlink shared channel (PDSCH) from the first downlink signal;
performing a first channel estimation operation using a first reference signal for demodulating the PDSCH;
performing a second channel estimation operation on at least one second symbol between at least two first symbols included in a symbol group unit based on a result of the first channel estimation operation, each time the first channel estimation operation on the symbol group unit is completed; and
performing a demodulation operation on the PDSCH based on a result of the second channel estimation operation,
wherein performing the second channel estimation operation comprises performing a time-axis or frequency-axis interpolation operation using channel values generated as the result of the first channel estimation operation and generating channel values corresponding to the at least one second symbol between the at least two first symbols.