Ceyear 4051 Series, Руководство пользователя

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8. Specifications and test methods
8.5 Performance characteristics test
653
4051 band division is ensured at the stage of design and manufacturing of the instrument.
b) Test procedure
1) Reset 4051 and set the center frequency as 1 GHz and the frequency span as 1 kHz.
2) Use the frequency diagnosis function in the analyzer system to display current first LO frequency LO1 as
5.95 GHz. According to design regulations, N value of band 0 is 0.5, and IF1 is 1.975 GHz, LO2 is 2.4
GHz, IF2 is 425MHz, LO3 is 500MHz and IF3 is 75MHz. Currently band 0 meets the frequency
conversion formulae 1 ~ 3.
IF
1
=N * LO
1
-RF .......................................................................................................... (1)
IF
2
= LO
2
-IF
1
................................................................................................................ (2)
IF
3
= LO
3
-IF
2
............................................................................................................... (3)
3) Reset 4051 and set the center frequency as 1 GHz and the frequency span as zero.
4) Use the frequency diagnosis function in the analyzer system to display current first LO frequency LO
1
as
6.225 GHz. According to the design, N value of band 0 is 0.5, and IF
1
is 5.225 GHz, LO2 is 4.8 GHz, IF
2
is 425MHz, LO3 is 500MHz and IF
3
is 75MHz. Currently band 0 meets the frequency conversion
formulae 4 ~ 6.
IF
1
=N * LO1-RF ......................................................................................................... (4)
IF
2
= IF1-LO
2
............................................................................................................... (5)
IF
3
= LO
3
- IF
2
.............................................................................................................. (6)
5) Each band has a frequency point according to band division (not in the band cross-covered region). Since
N value of band 2 is 1, that of band 3 and 4 is 5, and that of band 5 is 8, IF
2
is 425 MHz, LO
3
is 500 MHz
and IF
3
is 75 MHz. Band 2, 3 and 5 meet the frequency conversion formulae 6 and 7; band 4 meets the
frequency conversion formulae of 6 and 8.
IF
2
=N * LO
1
-RF .......................................................................................................... (7)
IF
2
=RF-N * LO
1
.......................................................................................................... (8)
c) Test records and data processing
6)
If all LO frequencies meet the frequency conversion formulae, “compliant” should be noted in the 4051
Record Sheet, otherwise it should be considered as noncompliant.
8.5.1.1.3 Frequency reference
a) Test items
Frequency reference is the basis of measurement by the spectrum analyzer. The frequency reference has a
high requirements for frequency accuracy and stability and uses complicated test equipment of the aging rate
and the temperature stability, featuring long test time and inapplicability in the production site test. During
acceptance and identification of the signal analyzer and production inspection, the main test target is the
reference frequency accuracy. The design nominal value of the frequency reference components can be used
to obtain the initial calibration accuracy. The aging rate and the temperature stability can be obtained by
sending sampled frequency reference components from production batches of each year to be tested by the
measurement body with the surveyor's certificate. See ―Regulation for Verification of Quartz Crystal
Oscillator in Electronic Measuring Instruments (JJG180-2002)‖ or equivalent methods for more details of test
methods.
b) Test equipment
Synthesized signal generator (E8257D/1464 is recommended)
Frequency standard
c) Test steps