中国科学F辑(英文版)
中國科學F輯(英文版)
중국과학F집(영문판)
SCIENCE IN CHINA(Series F)
2002年
3期
174-180
,共7页
邹红星%卢旭光%戴琼海%李衍达
鄒紅星%盧旭光%戴瓊海%李衍達
추홍성%로욱광%대경해%리연체
time-frequency analysis%Wigner-Ville distribution%cross-term cancellation
Wigner-Ville distribution (WVD) is recognized as being a powerful tool and a nucleus in time-frequency representation (TFR) which gives an excellent time-frequency concentration, and more importantly, has many desirable properties. A major shortcoming of WVD is the inherent cross-term (CT) interference. Although solutions to this problem from the bulk of contributions to the literature concerning TFR are currently available, none has been able to completely eliminate the CT's in WVD. It is therefore a common belief that if there exists an auxiliary time-frequency distribution (TFD) which has the same auto-terms (AT's) as that in WVD, but has CT's with the opposite sign, then, by adding the auxiliary TFD to WVD, an ideal TFD, which preserves the concentration of WVD while annihilating the CT's, is readily obtained. However, we prove that the auxiliary TFD does not exist. Moreover, it is found that in general, CT free joint distributions with their concentrations close to that of WVD do not exist either.