time-全讯担保网

digital am broadcasting (damb) channels are investigated in detail. first, the normalised ici power of time-variant damb channels is calculated to determine the range of total subcarriers of an ofdm-based damb system. the number of subcarriers provides a base for the subsequent channel estimation. then, two time-frequency channel estimators with real coefficients are constructed and analysed for a damb system based on ofdm. finally, their ber performance is simulated in damb channels. in conclusion, the 1-d estimator provides a better trade-off between ber performance and computational complexity than a 2-d estimator. the low complexity of a 1-d estimator makes it suitable for use in wireless communication systems such as wlan, dvb and so on.