User's Manual

CSM System Time – GPS & LFR/HSO Verification

68P09258A31–A

Oct 2003

1X SCt 4812T BTS Optimization/ATP

3-52

Table 3-20: GPS Initialization/Verification

Step Action

10 Observe the following typical response if the CSM is warmed up.

c:17486 off: –11, 3, 6 TK SRC:0 S0: 3 S1:–2013175,–2013175

c:17486 off: –11

, 3, 6 TK SRC:0 S0: 3 S1:–2013175,–2013175

c:17470 off: –11

, 1, 6 TK SRC:0 S0: 1 S1:–2013175,–2013175

c:17486 off: –11

, 3, 6 TK SRC:0 S0: 3 S1:–2013175,–2013175

c:17470 off: –11

, 1, 6 TK SRC:0 S0: 1 S1:–2013175,–2013175

c:17470 off: –11

, 1, 6 TK SRC:0 S0: 1 S1:–2013175,–2013175

11 Verify the following GPS information (underlined text above, from left to right):

– Lower limit offset from tracked source variable is not less than –60 (equates to 3µs limit).

– Upper limit offset from tracked source variable is not more than +60 (equates to 3µs limit).

– TK SRC: 0 is selected, where SRC 0 = GPS.

12 Enter the following commands at the CSM> prompt to exit the debug mode display.

debug dpllp

LFR Initialization/Verification

The LORAN–C LFR is a full size card that resides in the C–CCP Shelf.

The LFR is a completely self-contained unit that interfaces with the

CSM via a serial communications link. The CSM handles the overall

configuration and status monitoring functions of the LFR.

The LFR receives a 100 kHz, 35 kHz BW signal from up to 40 stations

(8 chains) simultaneously and provides the following major functions:

S Automatic antenna pre-amplifier calibration (using a second

differential pair between LFR and LFR antenna)

S A 1 second ±200 ηs strobe to the CSM

If the BTS is equipped with an LFR, follow the procedure in Table 3-21

to initialize the LFR and verify proper operation as a backup source for

the GPS.

NOTE

If CSMRefSrc2 = 2 in the CDF file, the BTS is equipped with

an LFR. If CSMRefSrc2 = 18, the BTS is equipped with an

HSO.