求翻译：目前，降低OFDM信号PAPR的方法很多，大体可以分成三大类：信号预畸变技术、编码类技术和概率类技术。这三种方法各有特色和着眼点，但每类方法都存在着缺陷。是什么意思？

At present, methods to reduce PAPR of OFDM signal a lot, can be roughly divided into three categories: signal pre-distortion technology, coding technologies and the probability of class type of technology. These three methods have their own characteristics and focus, but each class methods are flawe

At present, reduce OFDM PAPR signals a lot of methods can be roughly divided into three broad categories: signal pre-distortive technology, encoding type of technology and technology category probability. All three of these methods has its own unique features and focus, but every such methods contai

At present, reduces OFDM signal PAPR the method to be very many, may divide into three big kinds roughly: Signal pre-distortion technology, code class technology and probability class technology.These three methods have the characteristic and the objective point respectively, but each kind of method

At present, the method for reducing the PAPR of OFDM signals many, generally can be classified into three broad categories: pre-distortion techniques of signal probability class, coding technologies and techniques. These three methods have their own characteristics and focus, but each class methods

At present, methods to reduce PAPR of OFDM signal a lot, can be roughly divided into three categories: signal pre-distortion technology, coding technologies and the probability of class type of technology. These three methods have their own characteristics and focus, but each class methods are flawe