| 摘要 |
With the current explosion of information transfer, optic fibers are becoming faster all the time. Most of the recent advances in the amounts of data that these fibers can carry per time unit have come from adding more and more wavelengths (termed lambdas) to the same fiber at the same time, a method which is called DWDM (Dense Wave Division Multiplexing). Today a single optic fiber can carry up to 80 or even 160 different lambdas simultaneously and the number is likely to increase further. The fastest bit-rates achieved so far per each lambda are around 10 or 40 Gigabit per second, but it will be hard to go much beyond this, since higher bit-rates have much lower tolerance to dispersion problems. However, The demand for broadband communications, fueled mainly by the Internet growth, is still growing by a much faster rate than the growth in the abilities of optic fibers. Typically, this demand has risen in the last few years by a factor of up to 5-fold each year, and this demand will probably continue to grow. The present wisdom concentrates mainly on trying to increase the number of Lambdas per fiber, but after doubling it a few more times it will be difficult to increase it further. The present invention tries to achieve a large leap in this area by enabling putting much more fibers per cable, such as for example even 1,000 or 10,000 times more than what is being done today, with an increase in cost that is orders of magnitude smaller. The invention solves various mechanical, optical and electronic problems that stem from trying to cram so many fibers into one cable. One of the most important features is using multi-fiber flexible flat jackets that can move freely within the cable's pipe, preferably with the pipe divided into at least two cells, so that it can bend only in the desired direction and have maximum structural strength, and the connectors for these jackets can also solve many other problems. Another important feature is various methods for optimizing the efficiency of amplifying multiple fibers simultaneously. Another important feature is significantly reducing the cost of the end-equipment by using a novel method of duplicating each lambda into multiple fibers and on/off modulating it separately for each fiber, so that much less laser sources are needed.
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