--
[例句] 本发明提供一种用来将一输入信号降频为一输出信号的混频器. The invention provides a mixer which an input signal into an output signal through frequency reduction.
[例句] 直接降频转换接收器架构能够以较低成本提高无线系统基站接收器的性能. Framework of direct - down conversion receiver can provide upper performance with lower cost for wireless base receiver.