Patent ID: 7804395

Claim:
A mobile radio communication system estimating the positional relationship between the own moving terminal and the other moving terminal around a view obstruction, wherein the other moving terminal serves as a transmitting station in the mobile radio communication system and includes a transmission antenna having a predetermined transmission power level and a predetermined mounting height, wherein the own moving terminal serves as a receiving station in the mobile radio communication system and includes two reception antennas having different mounting heights, the mounting height of one reception antenna being different from that of the other reception antenna by a certain value or higher; reception power level detecting means for detecting the reception power level of a signal transmitted from the transmission antenna of the other moving terminal for every reception antenna; and absolute value determining means for determining whether the absolute value of the difference between the detected reception power levels is lower than a first power threshold value, wherein, if the absolute value is lower than the first power threshold value, the own moving terminal determines that the other moving terminal is positioned within the visual range of the own moving terminal, the distance from the own moving terminal to the other moving terminal being shorter than a predetermined distance B P , or that the other moving terminal is positioned outside the visual range of the own moving terminal, the distance to the visual range of the own moving terminal being shorter than the predetermined distance B P , and wherein, if the absolute value is higher than or equal to the first power threshold value, the own moving terminal determines that the other moving terminal is positioned within the visual range of the own moving terminal, the distance from the own moving terminal to the other moving terminal being longer than or equal to the predetermined distance B P , or that the other moving terminal is positioned outside the visual range of the own moving terminal, the distance to the visual range of the own moving terminal being longer than or equal to the predetermined distance B P .