She has recently begun to slouch over her typewriter.最近，她坐在打字机前就开始变得无精打采的。He straightened himself from a slouch.他一改刚才的无精打采，挺直了腰杆。Sit up straight. Don't slouch.挺起胸坐直，别歪歪斜斜的。...
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.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 provi...