【多选题】
【多选题】关于OFDM技术，下列说法正确的是（ ）。
A. OFDM系统的输出是多个子信道信号的叠加，如果多个信号的相位一致，所得到的叠加信号的瞬时功率就会远远高于信号的平均功率，即OFDM系统的PAPR较高。
B. LTE上行链路所采用的SFDMA多址接入技术基于DFTspreadOFDM传输方案。
C. OFDM调制对发射机的线性度，功耗提出了很高的要求，所以在LTE上行链路，基于OFDM的多址接入技术并不适合用在UE侧使用。
D. 上行采用SC-FDMA后，在降低峰均比的同时，也降低了频谱效率。
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