Appeal 2007-0680
Application 10/655,901
1 Grubb teaches many arrangements for optical communication
2 systems. Grubb teaches that optical pump energy can be supplied to an
3 optical fiber counter, and/or co-directionally to signal propagation (Grubb,
4 col. 9, ll. 10-26). Grubb teaches an arrangement in figure 5(a) where there
5 are several fiber segments 28, 30 and 40 and there are several pumping
6 sources (lasers items 32 and couplers 36). Figure 5(a) depicts the pumping
7 energy going through a distributor (item 24) and being coupled in manner
8 that appears to forward and reverse pump the fibers (note, signal propagation
9 is left-to-right, the splitters appear to provide pumping power to fibers to the
10 left (counter pumping) and the right (co-pumping)). However, the
11 description of figure 5(a) states that the pump source provides power
12 “counter-directionally to the optical signals being transmitted.” (Grubb, col.
13 9, ll. 28-33). Further, we note that Grubb states that distributor 24 is “known
14 in the art” and provides no explanation of whether it produces an even split
15 of the signal or an uneven split of the signal. Thus, we do not find
16 substantial evidence that the embodiment depicted in figure 5(a) teaches
17 splitting the power from one source to counter pump one fiber segment and
18 co-pump another segment or that the distributor (item 24) unequally splits
19 the beam.
20 Fludger teaches that systems which use Raman fiber amplifiers may
21 be co-pumped or counter-pumped (Fludger, introduction on p. 15). Fludger
22 discusses the effects of each on relative intensity noise (RIN). Fludger
23 concludes that in counter-pumped Raman amplification the different
24 directions of propagation cause the noise to be low pass filtered (Fludger,
25 conclusion on p. 17). We find no discussion in Fludger of splitting the beam
5
Page: Previous 1 2 3 4 5 6 7 8 9 10 Next
Last modified: September 9, 2013