MU120131A/32A PON Quick Start Guide
32
5. Monitoring E-PON Systems
This part explains the procedure for monitoring E-PON systems.
In concrete terms, we shall capture PON system Frames and check that MPCP (Multi-Point
Control Protocol) control and the OAM (Operations, Administration, and Maintenance) function
are operating correctly. Additionally, how to check the OLT DBA (Dynamic Bandwidth Allocation)
function and how to change priority are explained as well.
In other words, the procedures for testing service provider services are explained.
5.1. Connecting DUT
Connecting with Coupler
OLT
ONU
3 dB Coupler
ONU
ONU
・
・
・
1310 nm
1490 nm
P
out
= -3 to +2 dBm (PX10),
P
out
= +2 to +7 dBm (PX20)
P
out
= -1 to +4 dBm (PX10),
P
out
= -1 to +4 dBm (PX20)
P
in
= -24 to -3 dBm (PX10, PX20)
P
in
= -24 to -1 dBm (PX10),
P
in
= -27 to -6 dBm (PX20)
MD1230 Optical sensitivity: -22 to -3 dBm (1260 to 1580 nm)
1490 nm
1310 nm
<3 dB Coupler Specifications>
Wavelength =1260 to 1360,
1480 to 1580 nm
Insertion Loss
≦
3.70 dB
Port2
Port1
ATT
ATT
Insert a 2 x 2 coupler between the OLT in the PON system and splitter. Here the
coupler is connected directly after the OLT.
Note: When the distance between the OLT and ONU is short, sometimes the
equipment permissible optical power range may be exceeded. In this case,
insert an optical attenuator (ATT) directly after the OLT.
Since light has directivity, connect the coupler end of the side monitoring the Down
signal (1490 nm) to Port 1 of the MU120132A (Unit5) as shown in the above diagram.
Connect the Up signal (1310 nm) to Port 2. Since high power light is input to the receiver,
use a 6 dB optical ATT inserted at the input section of the measuring instrument when the
OLT and each ONU use 1000Base-PX10, and a 12 dB optical ATT when they use
1000Base-PX20. (This is not necessary when the power is -3 dBm or less.)
*The coupler characteristics are as described above. Use a coupler with a normal
extinction ratio (50:50) from any maker.
Note: Normally, since the reflected/leakage light is 40 to 50 dB less, the impact on
the optical signal is small, but reflection from an open connector can have an