MobileAccess 1000 System, Руководство по установке и настройке

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Appendices MobileAccess™ 1000/1200
28
UM-1000, Revision 2.2
Following the completion of the insertion loss test, the return loss test determines the
optical signal power that returns to the laser. The return power affects the laser,
changing the laser’s base current.
4.1.3 Test Equipment
In order to perform these tests, the following equipment is necessary:
•
Light source (for wavelength 1310nm , 0dbm)
•
Optical power meter
•
Optical coupler (hosed and connectorized)
•
Fiber optic jumper
•
Adapter parts for the cable connectors
For information about equipment suppliers, contact MobileAccess.
4.1.4 Optical Insertion Loss Measurement Test
The optical insertion loss measurement tests the attenuation of the cable. The
insertion loss’ value should be minimal and remain in scale to 0.4dB/Km.
The insertion loss measurement can be performed in two methods:
•
Two point test
•
Single point test
4.1.4.1 Method #1: Two Point Test
Connection description: Light source connected at one end of the cable and an
optical power meter at the other end.
Light
source
Optical
power
meter
Figure 4-1: Two Point Test
1. Connect light source directly to the optical power meter.
2. Measure light source signal power, verifying power of 0dBm.
3. Connect light source to cable end.
4. Connect optical power meter to cable at other end.
5. Measure light source signal power using the optical power meter.
6. Calculate the difference between two signals (dB):
(Insertion loss)dB = (Light source signal at one end)dBm – (Measured signal at other end)dBm