| 摘要 |
<p>PURPOSE:To measure the quantity of propagation attenuation between a transmission antenna and a reception antenna by using a signal in the course of relaying, by allowing a transmission signal frequency slightly to offset from a reception signal frequency, and detecting a transmission signal component contained in a reception signal. CONSTITUTION:After a signal inputted from the transmission antenna 1 (outgoing line signal) is shifted by a few definite frequency (e.g., 100Hz) by a frequency converter 12, and is amplified by an amplifier 13, it is transmitted as a transmission signal from the transmission antenna 4. When the transmission antenna and the reception antenna are coupled, a ripple equal to the shift quantity is generated in a reception signal envelope, and the magnitude of the ripple is proportional to coupling quantity between the transmission and the reception antenna. A level detector 16 detects the presence and absence of a level for the whole outgoing lines, and monitors a channel being used by a base station. The smallest value of the attenuation quantity among the measured propagation attenuation quantities of respective bands between the transmission and reception antennas is considered to be the propagation attenuation quantity between the transmission and the reception antennas, and at the time of the installation of a radio repeater, a repeating gain is set so as not to exceed said attenuation quantity.</p> |
