MIL-STD-469B APPENDIX A
Signal substitute the test signal generator to the FSVM input. The output level should be adjusted to regain the
reference FSVM reading obtained with the radar signal. Note the resulting level as P
GEN.
40.2.4.4 If the broadband crystal detector with oscilloscope is used for the test receiver, the attenuator at the signal sampler should be adjusted to yield a level within the detector linear range. With the oscilloscope adjusted for a stable pulse display, note maximum display amplitude for reference. Adjust the test signal generator pulse width and reference the signal generator power level to the power meter as described for the measurements with the FSVM test receiver. Signal substitute the test signal generator output to the broadband crystal detector and adjust the output level to regain the reference oscilloscope display amplitude. Note the resulting level as PGEN.
40.2.5 Sample calculations.
40.2.5.1 A sample calculation of the peak power output, using the measured average power, is as follows: Measured data:
Transmitter tuned frequency (F o): 5000 MHz
Pulse width (t): 1.3 microseconds
PRF: 650 pps
Power meter reading (P M): 1.7 dBm
Attenuation inserted (A 1): 0.0 dB
Signal sampler coupling factor (A S): 50.0 dB
Transmission line attenuation, signal sampler to antenna (A 2): 1.0 dB
The average power output is calculated as follows:
Pavg = PM + AS + A1 A2
= 1.7 dBm + 50.0 dB + 0.0 dB 1.0 dB
= 47.3 dBm
The peak power output (P p, in dBm) is determined from the duty cycle (t)(PRF) using the following relationship:
Pp =
therefore,
avg + 60.0 - 10
P log (t x PRF)
Pp = 47.3 dBm + 60.0 -
10 log (1.3 x 650)
= 47.3 dBm + 30.7 dB
= 78.0 dBm.
40.2.5.2 A sample calculation of peak power output from measured peak power data follows: Measured data:
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