Radio communication apparatus

Abstract

Abstract PURPOSE: To improve the reception spurious response by securing the oscillation of the frequency higher than the reception frequency of the 1st intermediate frequency by the amount equivalent to the 2nd intermediate frequency at the local oscillation part where the 1st intermediate frequency is converted into the 2nd intermediate frequency. CONSTITUTION: The radio communication apparatus consists of antenna 1, common filter 2, transmission part 3, reception part 4', frequency synthsizer 30 and control part 31 each. And with application of the channel CH designation No. to terminal Y, the 1st local oscillation is selected from control part 31. The 2nd local oscillation part 32 comprises crystal oscillator 33 featuring the frequency higher than 1st intermediate frequency f i1 by 2nd intermediate frequency f i2 , crystal oscillator 34 featuring the frequency lower than f i1 by f i2 , oscillation part 35 plus switches 36 and 37 each. Thus the selection is decided between these two oscillators with every CH designation No. and by the CH designation which is memorized previously at control part 31. In this way, the reception spurious response can be improved greatly, thus omitting the highly rated common filter and thus realizing an effective utilization of the frequency. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Katsuhiro Shiomi

Bibliographic Details