| 摘要 |
PROBLEM TO BE SOLVED: To prevent the falling into a communication impossible state when a receiving state deteriorated because of interference concerning the communication systems of a mobile object in which a mobile station radio-communicates through a base station. SOLUTION: Plural interference detection stations 2 to 9 are fixedly arranged within the prescribed zone of the base station 1. These interference detection stations 2 to 9 are connected with the base station 1 by a cable line and on the other hand, constantly receives a transmitted radio wave from the base station. A receiving state monitoring means 2a receives a transmission signal from the base station and monitors a receiving state. When the transmission signal is judged to receive prescribed interference, an interference detection signal output means 2b outputs an interference detection signal to the base station through the cable line. At the time of receiving the interference detection signal, a carrier switching control means 10 switches the carrier of the transmission signal sent from the base station to the carrier of another frequency if a prescribed condition is satisfied. |
