基于离散哈特莱变换的LACO-OFDM低复杂度接收方法研究

Study of LACO-OFDM low-complexity reception method based on discrete Hartley transform

在分层非对称限幅光正交频分复用(LACO-OFDM)中,采用离散哈特莱变换(DHT)可以弥补采用快速傅里叶变换(FFT)时存在的频谱效率不高的缺陷,但在接收端多层信号的分离仍存在计算复杂度高的问题。结合DHT-LACO-OFDM信号的时域对称和反对称特性,提出一种基于时域重构的分层信号接收方法,在时域把叠加的信号进行分层接收。研究结果表明,相比于传统的时频域结合的迭代接收方式,基于时域重构的分层信号接收方法在误比特性能上与传统的迭代接收方式几乎相同,但计算复杂度约降低为原来的一半。

In the layered asymmetric clipped optical orthogonal frequency division multiplexing(LACO-OFDM), the use of discrete Hartley transform(DHT) can makes up for the low spectral efficiency of fast Fourier transform(FFT), but there is still a problem of high computational complexity in the separation of multi-layer signals at the receiving end. Combined with the time-domain symmetry and anti-symmetry characteristics of the DHT-LACO-OFDM signal, a layered signal receiving method based on time domain reconstruction is proposed, in which the superimposed signal is received layered in the time domain. The results of the study show that, compared with the traditional iterative receiving method combining time-frequency domain, the layered signal receiving method based on time-domain reconstruction has almost the same bit error performance as the traditional iterative receiving method, but the computational complexity is reduced by half.