Safran CORTEX CRT Quantum - ESA Code Standard

COMMAND RANGING & TELEMETRY UNIT CORTEX
CRT QUANTUM USER'S MANUAL
Ref. DTU 100042
Is.Rev. 5.17
Date: Dec.
03, 2021Sept. 30, 2021
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Page 168
 Scenario 3 (select Fixed amb.):
The set time for the major and minor tones depends on two factors:
 the RAU PLL bandwidth (parameter Loop Bandwidth)
 the maximum one-way satellite distance (parameter: Maximum Distance)
PLL bandwidth (2Bn) = 1 to 8 Hz:
Ta = Ts = 2 +


(in seconds)
T =


(in seconds)
PLL bandwidth (2Bn) < 1 Hz:
Ta = Ts =





(in seconds)
T =


(in seconds)
where d is the programmed maximum satellite-to-earth distance and c is the light speed (3 x 10
8
m/s). Values are rounded up to the nearest whole number of resolution steps (resolution step ≈
13.1 ms).
Ambiguity solving (distance computation) is performed in the range 0 to the wavelength of the
lowest virtual minor tone. Do not use this setting in case of non-integer ratio between minor tone
“Q” factors.
 Scenario 4 (select No fixed):
The set times for the major and minor tones are as per scenario 3. Ambiguity solving is as per
scenario 2. Use this setting in case of non-integer ratio between minor tone “Q” factors.
3.6.4.7.2. ESA Code Standard
The ambiguity distance is given by the code length parameter.
The tone and code set times (sequence timing) are automatically adjusted, depending on the loop bandwidth, the
code length and the tone frequency (see sections 3.6.11.3 to 3.6.11.5).