基于多载波调制的远动信号传输

Tele-control Signal Transmission Based on Multi-carrier Modulation

单边带电力线载波机一般采用频移键控调制方式实现远动信号的传输,在话音与远动复用时,远动信号传输速率不超过600bit/s,而在远动专用时,远动信号传输速率不超过1200bit/s。为了提高远动信号的传输速率,提出了一种基于多载波调制原理实现远动信号传输的方法。该方法对输入数据进行串/并变换、数据编码,接着插入帧同步序列、信号映射,然后进行离散傅里叶反变换从而实现多载波调制;对多载波输入信号进行抽样、离散傅里叶变换、信号逆映射,然后删除帧同步序列、解码、并/串变换从而恢复出原始数据。

Single-side-band power line carrier equipment usually uses the modulating method of frequency shift keying （FSK） to implement tele-control signal transmission, in which the transmission rate exceeds neither 600 bit/s in the speech and tele- contol simultaneous multipurpose mode nor 1 200 bit/s in the tele-control single-purpose mode. To increase the tele-control signal transmission rate, this paper proposes a new transmission method based on the multi-carrier modulation （MCM） scheme. The transmission principle is to convert a serial data stream into a coded parallel data stream, insert a frame synchronization sequence into a data stream and map it, then modulate the data stream by the inverse discrete Fourier transform （IDFT）. In the reverse direction, the input multi-carrier signal is sampled, demodulated by the discrete Fourier transform （DFT） and the inverse signal mapping, then the frame synchronization sequence is removed and decoded, till finally restoring the original data using parallel-to-serial conversion.