| 摘要 |
PURPOSE:To prevent data missing due to invasion of external noise and to make the equipment operationable with low power by providing a feedback path comprising of a 1st transceiver and a 2nd transceiver and a signal path. CONSTITUTION:An amplified signal from a 1st transceiver 12 is received by a 2nd transceiver 12a and a signal received by a mixer 18a in the 2nd transceiver 12a is mixed with an output signal of the 2nd transceiver 12a to generate a 2nd difference frequency. The 2nd difference frequency is amplified to a level able to be detected when the input signal is not a signal with a proper difference frequency and controls the output frequency of the data signal sent from the 2nd transceiver 12a. The output frequency of the data signal controls the 1st difference frequency generated in the 1st transceiver 12 and controls the 1st and 2nd transceivers 12, 12a to make the operation of the feedback path complete. Thus, even when a supply power level is low with noisy environment, the data communication is surely and safely attained. |
