Optical Wireless Link Availability and Bit Error Ratio

In this article the determination of the time ratio of the optical wireless link (OWL) availability is considered. The possibility how to realize the bit error rate tester with El/Tl interface is presented. By means of this indicator we are able to establish the bit error ratio (BER) of the specific optical link and the percentage of link unavailability. We can determine these parameters for arbitrary time period. The influence of atmospheric attenuation on links parameters listed above is interesting. In this article the statistics of meteorological visibility for the year 2006 is also stated. With these data we can determine the percentage that the certain value of atmospheric attenuation occurs. Eventually it is shown that not only meteorological visibility is important for the OWL function.