M. Bilal Aziz;Stavros Giannakopoulos;Alexander Grabowski;Peter Andrekson
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引用次数: 0
Abstract
The use of long pseudo-random bit sequences to emulate random data in optical transmission links often gives rise to degradation of the receiver sensitivity for a given target bit error rate resulting in a power budget penalty. This is a well know fact and conventionally attributed to the non-ideal response of the system at very low frequencies. Here, we investigate this in the context of directly-modulated vertical-cavity surface emitting laser (VCSEL) based optical interconnects. We observe, both in simulations and in experiments, a substantial increase in the penalty with long sequences especially at symbol rates exceeding the VCSEL bandwidth. Our results show that this is related to the high frequency dynamic behavior of the VCSEL itself and we identify a few certain short bit sequences that cause the large penalty observed. We also show that the penalty can be significantly reduced by a simple modification of the sequences.
期刊介绍:
IEEE Photonics Technology Letters addresses all aspects of the IEEE Photonics Society Constitutional Field of Interest with emphasis on photonic/lightwave components and applications, laser physics and systems and laser/electro-optics technology. Examples of subject areas for the above areas of concentration are integrated optic and optoelectronic devices, high-power laser arrays (e.g. diode, CO2), free electron lasers, solid, state lasers, laser materials'' interactions and femtosecond laser techniques. The letters journal publishes engineering, applied physics and physics oriented papers. Emphasis is on rapid publication of timely manuscripts. A goal is to provide a focal point of quality engineering-oriented papers in the electro-optics field not found in other rapid-publication journals.