| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to receive only a burst of high reception electric field level even when the burst of low reception electric field level is laid over the burst of high reception electric field level by making a UW detection window for a UW detection circuit open only when the reception electric field level is higher than a threshold. SOLUTION: A control part 8 sets a threshold in a reception electric field level comparison control means 10 in advance before starting level boarding operation. The reception electric field level comparison control means 10 compares an A/D conversion value (a reception electric field level) obtained from an A/D conversion means 9 during the level boarding operation with the threshold set by the control part 8 and, only when the reception electric field level is higher than the threshold, it is control so that a UW detection window of a UW detection part 5 is made to open. When the reception electric field level is lower than the threshold, it is control so that the UW detection window of the UW detection part 5 is made to close. |
