Input Frequency; Table 32: Examples Of Downlink Converter Setup With - Safran CORTEX CRT Quantum User Manual

3.8.1.1. Input Frequency

The frequency domain can be:

60 to 78 MHz for IF legacy operation. In this case, the EFC programs automatically the bypass
function

930 to 2400 MHz for L/S-Band Operation.
Important Note
Please note that,

To obtain an accurate base-band transposition of the RF signal, there are two parameters to be set:

The RF converter frequency (with 5MHz step*) for down conversion L/S band to the intermediate
band

The Input frequency of the IF Receiver (with an accuracy of the Microhertz) for the down conversion
intermediate band to base band
The IF frequency shall be adapted accordingly to the RF frequency.
The formulas given the RF converter frequency and the IF frequency are:
EFC converter frequency = the multiple of 5MHz nearest to the RF input frequency
IF frequency = 70MHz + (RF input frequency – EFC converter frequency)
*Remark: The local oscillator used on the EFC board has been chosen to guarantee a good phase noise. In
return the frequency step of the oscillator is 5 MHz.
Here below some examples of downlink conversion setup:
RF input
signal
frequency
975 MHz
975,1 MHz
2203,5 MHz
© Safran Data Systems
COMMAND RANGING & TELEMETRY UNIT CORTEX
CRT QUANTUM USER'S MANUAL
EFC converter
frequency
975 MHz
975 MHz
2205 MHz
Table 32: Examples of downlink converter setup with EFC
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It cannot be duplicated or distributed without expressed written consent.
IF signal frequency
70 + (975 – 975) = 70 MHz
70 + (975,1 – 975) = 70,1 MHz
70 + (2203,5 – 2205) = 68,5 MHz
Safran Data Systems
.
Ref. DTU 100042
Is.Rev. 5.17
Date: Dec.
03, 2021Sept. 30, 2021
IFR input
frequency
70 MHz
70,1 MHz
68,5 MHz
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