一篇激光调制解调的个人翻译.docVIP

8Gbit/s FSK MODULATION OF DFB LASERS WITH OPTICAL DEMODULATION DFB型Indexing terms: Optical communications, Semiconductor lasers, Optical modulation, Optical receivers 关键字：光通信，半导体激光器， 光调制，光接收机 Single-contact DFB lasers were frequency modulated by pseudorandom data at rates up to 8 Gbit/s by direct current modulation with no pre-equalisation of the modulation signal. The signals were optically demodulated by Fabry- Perot interferometers for conversion to ASK signals which were detected by a direct-detection receiver. At 8Gbit/s the receiver sensitivity was -22dBm. 以往的接触式单点分布反馈激光器8 Gbit/s。 调制信号直接使用无预均衡的电流进行调制。 已调信号由法布里-佩罗特干涉仪进行光解调，并转换成ASK信号，该信号由直接检测接收机进行检测。在8 Gbit/s的速率下，接收机的灵敏度为-22dBm。 For semiconductor lasers directly modulated at high data rates, frequency-shift-keyed (FSK) modulation formats are preferable to amplitude-shift-keyed (ASK) formats for several reasons. 对于工作在高数据率下的直接调制半导体激光器，由于各种原因，频移键控（FSK）调制比振幅键控（ASK）调制形式性能更好。 The current drive to the laser required for FSK modulation (which slightly changes the laser frequency while the laser is biased well above threshold) is typically much smaller than that required for ASK modulation (which drives the laser from a high bias level down to near threshold). 这个用于驱动激光器产生频移键控调制的电流，（产生的激光频率略有改变，并远高于阀值），通常远小于振幅键控所需的电流，并驱使激光从一个较高的偏移下降到阀值附近。 This reduction in drive requirement is especially significant at very high bit rates where high-speed, high-power laser driver circuits are difficult to fabricate 减少启动器对电流的需求具有重要意义，尤其在高比特率，高速的情况下，高功率的激光驱动电路是很难制造、实现的。 The small drive in a FSK format also leads to a relatively compact laser spectrum which minimises the problem of fibre chromatic dispersion and makes efficient use of the frequency spectrum for WDM purposes. 在FSK形式下的小驱动器也使得激光光谱变得相对紧凑，并最大限度的减少了光纤色散的问题，从而更有效的利用频谱，达到波分复用的目的。 Typically, FSK signals used in heterodyne configurations are electronically demodulated.1－8 However, FSK signals can also be optically demodulated effectively by converting the signals to baseband ASK s