| 摘要 |
PROBLEM TO BE SOLVED: To provide a user with accurate information that predicts not only the current reception sensitivity but also the reception sensitivity in the further. SOLUTION: A received signal is inputted to a reception tuner 8 and a sensitivity measurement tuner 10. The tuner 10 measures the reception sensitivity for all frequencies within a prescribed range. Detected sensitivity is stored in a sensitivity storing part 14. A controlling part 2 compares the current sensitivity with the past sensitivity before a waiting time and calculates reception sensitivity increase/decrease information. The current sensitivity and the sensitivity increase/decrease information are shown with an arrow on a display 20. The length of the arrow shoes sensitivity dimensions and the direction of the arrow shows the sensitivity increase/decrease information. A user who sees the arrow knows the current sensitivity and further predicts how sensitivity will change in the further. It is preferable to adjust the waiting time that is a processing cycle, in accordance with the moving speed of a mobile body. |
