Doppler Computing - Safran CORTEX CRT Quantum User Manual

3.3.4.4. Doppler Computing

The Doppler measurements are computed owing to the accumulated phase interpolated every ���� seconds
according to the formula :
where ∆�� is the computed Doppler, ��
-32
resolution of 2 cycle.
The Doppler error is:
With:
Where:
And:
Where:
So:
Where D(t) is the input Doppler
A typical second-order Doppler variation of 10 Hz.s
error lower than (4.16x10
Hz for a sampling period Ts of 10s.
© Safran Data Systems
COMMAND RANGING & TELEMETRY UNIT CORTEX
CRT QUANTUM USER'S MANUAL
∆��(�� + ���� ��
is the IF Receiver centre frequency and �� the accumulated phase with a
������
(�� + ���� ��
�� ⁄ ) =
������
�� ( �� + ���� ) = �� ( �� ) + ���� × ��
‖ ���� (�� + ����) ‖ ≤
��
����
��'(�� + ���� ��
⁄ ) = ��' ( �� ) +
(�� + ���� ��
‖����'
��
��
����
(�� + ���� ��
‖�� ⁄ )‖ ≤
������
����
-3 -9
+ 6.25x10 ) Hz for a sampling period Ts of 0.1 s, and lower than (41.6 + 6.25x10
This document is the property of
It cannot be duplicated or distributed without expressed written consent.
�� �� ( ��+���� ) −�� ( �� )
⁄ ) = × − ��
����
�� ����
�� ( �� + ���� ) − �� ( �� )
− ��'(�� + ���� ��
����
�� ��
���� ����
' ''
( �� ) +
(��) + ��
�� ��
��
����
× ������ ‖��
��!
��∈]��,��+����[
��
( ���� ��
⁄ )
'' (��)
× �� (��) + ��
�� ��
��
( ���� ��
⁄ )
⁄ )‖ ≤ × ������
��!
��∈]��,��+����[
����
( �� )
( �� ) ‖ +
× ������ ‖��
����
��∈]��,��+����[
-2
and third-order Doppler variation of 10
Safran Data Systems
.
Ref. DTU 100042
Is.Rev.
Date:
03, 2021Sept. 30, 2021
,
������
⁄ )
( �� )
( �� ) + ����
�� (�� + ����)
��
(��)
(��)‖
(�� + ���� ��
( �� ) + ����' ⁄ )
��
(��)
‖�� (��)‖
��
(��)
× ������ ‖�� (��)‖
��∈]��,��+����[
-4
Hz.s
5.17
Dec.
-3
give a phase
-3
)
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