| 摘要 |
PURPOSE:To prevent leakage of a transmission intermediate frequency carrier output and a transmission RF carrier output to a reception section in a same case resulting in causing the occurrence of same channel interference when a same frequency carrier is used for the transmission and reception in the TDMA/TDD system radio telephone set. CONSTITUTION:A frequency divider type orthogonal modulator 111 having a frequency divider 202 which receives a local signal whose frequency is four times an intermediate frequency and divides the frequency of the local signal to 1/4 and generates a carrier whose phase differs by 90 deg.. and outputting an intermediate frequency carrier applying orthogonal modulation to the modulated signal with the carrier features to stop the operation of the frequency divider 202 at reception and does not output the orthogonal modulation intermediate frequency carrier. |
