Safran CORTEX CRT Quantum User Manual page 53

Satellite Ranging
1.6.3.

Ranging standards

Ranging tones

Code length

Integration time

Downlink tone tracking

PLL bandwidth (2 Bn)
 Measurement standard deviation ≤ 1dB vs theory in the presence of noise

Phase measurement resolution

PN Ranging Measurement degradation

Ambiguity solving (after Doppler compensation on minor tones and programmable phase corrections)

Distance measurement resolution

Local ranging capability

Doppler Rate Aid capability and Doppler Aid capability

Hybrid Ranging:
o
Uplink:

MTC2: PCM/SRRC-UQPSK / ETSI EN301 926 compliant +:
 Chiprate up to 3.9 Mchips/s
 Code Length: I rail
 Code Length: Q rail
 RRC rolloff from 0.2 to 0.9
o
Downlink:

Carrier is PM modulated by ranging tones.

Up to 8 tones defined by ratio tone frequency / long code epoch rate (code on Q rail)

Integration time in multiples of long code Epoch period.
© Safran Data Systems
COMMAND RANGING & TELEMETRY UNIT CORTEX
CRT QUANTUM USER'S MANUAL
ESA tone and ESA code standards
ESA-like and USB tone standards (programmable frequencies and tone
sequence)
INMARSAT and LMCO tone standards
PN Codes (CRT eXplorer only)
Hybrid Ranging (SQPN uplink / PM downlink)
Tone frequency
Number of tones
0 to 24 (ESA code standard), 2 or 4 (PN Codes)
0.25 to 500 seconds
2nd-order digital PLL
0.1 to 8 Hz (CRT XL Quantum)
0.001 to 8 Hz (CRT eXplorer)
0.0055° (360°/216)
< 0.5 dB from theory (vs noise). See section 3.6.12
1 ns
This document is the property of Safran Data Systems.
It cannot be duplicated or distributed without expressed written consent.
: 2 Hz to 1.5 MHz
: 1 major tone, 1 to 6 minor tones (8 for USB)
L
9 ≤ L ≤ 13
2 -1,
L X
5 ≤ X ≤ 9
(2 -1)2
Ref. DTU 100042
Is.Rev. 5.17
Date: Dec. 03, 2021Sept.
30, 2021
Page 28