基于复小波变换的OCWDM多载波调制系统用于DVB-T

Multicarrier Modulation Based on Dual-Tree Complex Wavelet Transform Applied in DVB-T

用二元树复小波变换取代OFDM中的傅立叶变换,应用于DVB系统.在DVB-T中,将OrthogonalComplex Wavelet Division Multiplex(OCWDM)多载波调制系统在高斯信道、平坦衰落信道、频率选择性信道中进行仿真.同OFDM相比较,OCWDM在高斯信道和平坦衰落信道下误码率有着明显的降低;在频率选择性信道下,OCWDM的误码率也低于OFDM.OCWDM有着很好的抗噪声和抗衰落、抗多径特性.DTCWT的小波基具有正交性,不需要循环前缀来消除码间干扰和子载波间干扰,简化了OCWDM调制过程.DTCWT可以直接通过数字滤波器实现,运算复杂度低,硬件实现简单.OCWDM在DVB系统中有着很好的应用前景.

Dual-Tree Complex Wavelet Transform（DTCWT） replaces DFT in OWDM applied in DVB system.In DVB-T,Orthogonal Complex Wavelet Division Multiplex（OCWDM） is simulated in gauss channel,flat fading channel and frequency selective channel.The results show that OCWDM has much lower BER compared with OFDM in gauss channel and in flat fading channel.Also in frequency selective channel OCWDM outperforms OFDM.OCWDM has good de-noising property,anti-fading property and anti-multipath property.OCWDM does not need CP to reduce ISI and ICI because of its orthogonality.It simplifies modulation steps.DTCWT can be realized by digital filters.It reduces computational complexity and OCWDM can be realized by hardware easily.OCWDM applied in DVB-T has a broad sight.