In a communication system, a base station transmits power setting information in a downlink Physical Downlink Shared Channel (PDSCH). A mapping scheme between overhead signals and reference signal (RS) overhead ratios, and the traffic-to-pilot ratios (T2P) calculation methods are established. A user-specific T2P ratio for certain OFDM symbols, a RS overhead ratio and a calculation method selected from the plurality of T2P calculation methods are assigned to a wireless terminal. An overhead signal corresponding to the assigned RS overhead ratio and the assigned T2P calculation method is selected in accordance with the mapping scheme and transmitted to the wireless terminal. In addition, the user-specific traffic-to-pilot ratio is transmitted to the wireless terminal. The wireless terminal calculates the traffic-to-pilot ratios across different transmission antennas and different OFDM symbols based on the received traffic-to-pilot ratio, the RS overhead ratio and the T2P calculation method indicated by the RS overhead signal.