| 摘要 |
PURPOSE:To expand the service area by sending weak radio wave of the same content from each of plural transmission antennas in a different frequency and setting each transmission frequency in the range of reception frequency locking of the receiver receiving a weak radio wave so as to eliminate the operation such as zone switching at the reception side. CONSTITUTION:Weak radio wave sending points A0, A1...A4 radiate the radio wave of the same content in different transmission frequencies. Then the transmission frequency at the transmission points A0, A1,...A4 of each zone is set in the reception frequency locking range of the receiver. Thus, when an FM receiver is being moved, the transmission frequency of the zone is locked in the AFC circuit of the receiver and the receiver is automatically tuned to the transmission frequency. Thus, in forming the sender size by plural transmission frequencies slightly different so as to be locked sufficiently in the AFC circuit at the reception side as a multizone, the reception side can receive the signal in plural zones consecutively without the need of any operation such as zone changeover. |
