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对起、止频率为FS_FE_的带通信号的直接采样,传统上要求信号是窄带的9即F≥F_E/2),否则只能用经典的SHANNON采样定理,以不低于2F_A的采样率来采样才能恢复信号.该文采取半均匀采样技巧,突破了这一限制.对满足F_S≥F_E/3的宽带带通信号,建立了精确的恢复公式,采样率为4FE/3,低于NYQUIST率;如果F_S＜F_E/3,用TILING分析技术可以证明无论是均匀还是半均匀采样,最低采样率必然是2F_E.这表明该文所给出的宽带条件是最优的.“,”The traditional sampling theorem for band-pass signals holds only for narrow band case f>f/2 provided the cut-off frequencies are fand fe, otherwise one can only sample with at ho Nyquist rate. We im prove this' theory by introducing a semi-uniform Samping scheme for wide band-pass signals under the assumption that fs fe/3, in which the the reduced sampling rate is 4fe/3, which is las than Nyquist Nyquist 2fe. If this condition breads down, a tiling analysis assocthe with spectrum theory asserts that we must return back to Shannon's theo- ry. Thus our result is optimal, and the conditionf_e;>f_e/3 can not be tmproved.