2[2]CCIR (now ITU-R) Report 567-4. Propagation data and prediction methods for the terrestrial land mobile service using the frequency range 30 MHz to 3 GHz[R]. International Telecommunication Union, Geneva, 1990:321.
3[3]Okumura S, Ohmori Y E, Kawano T. Field strength and its variability in VHF and UHF land-mobile radio service[J]. Review of the Electrical Communications Laboratory, 1968, 16(9-10): 825-843.
4[4]Hata M. Empirical formula for propagation loss in land mobile radio services[J]. IEEE Transactions on Vehicular Technology, 1980, 29(3):317-325.
5[5]Andersen J B, Rappaport T S and Yoshida S. Propagation measurements and models for wireless communications channels[J]. IEEE Communications Magazine, 1995: 42-49.