Joint 5G NR-NTN and GNSS Overlay in MEO: Experimental Assessment of Navigation Data Robustness under DSSS–OFDM Coexistence

October 7, 2026·
Idir Edjekouane
,
Alejandro Gonzalez Garrido
,
Jevgenij Krivochiza
,
Jorge Querol
,
Symeon Chatzinotas
· 2 min read
DOI
Abstract
Recent advances in Joint Communication and Positioning (JCAP) motivate the integration of navigation signals within communication waveforms. This paper investigates a hybrid Direct-Sequence Spread Spectrum (DSSS)–Orthogonal Frequency-Division Multiplexing (OFDM) waveform in which a low-power legacy Global Positioning System (GPS) L1 Coarse/Acquisition (C/A) signal carrying the Legacy Navigation Message (LNAV) message is intentionally overlaid on a Fifth Generation (5G) New Radio (NR) Non-Terrestrial Network (NTN) downlink. The focus is on the Global Navigation Satellite System (GNSS)-side ability to acquire, track, and demodulate the navigation message in the presence of structured 5G interference. The study considers a Medium Earth Orbit (MEO) scenario representative of the SES O3b mPOWER constellation at an altitude of approximately 8000 km. First, MEO Doppler dynamics are characterized using representative orbital parameters, and Monte Carlo (MC) simulations are performed to evaluate LNAV recovery versus Signal-to-Interference-plus-Noise Ratio (SINR) for different transmitted Signal-to-Interference Ratio (SIR) levels. Performance is assessed using navigation-centric metrics, including Bit Error Rate (BER), valid 6 s subframe decoding, valid decoding of the first three subframes, and complete 30 s LNAV frame recovery. The same 35 s reference composite waveform is then transmitted in a continuous loop through the SES O3b mPOWER transparent MEO relay. For each tested SIR level, 300 s of baseband In-phase and Quadrature (I/Q) samples are recorded and processed offline using a MATLAB-based GNSS receiver with 5G Synchronization Signal Block (SSB)-assisted frequency initialization. Simulation results show that, in the considered MEO scenario, Doppler dynamics are moderate and do not constitute the dominant limitation; performance is mainly governed by thermal noise and 5G interference. Experimental results demonstrate reliable LNAV recovery down to approximately -25 dB transmitted SIR, while end-to-end recovery becomes unreliable at -30 dB and below. Since the effective received SINR is not directly available, the experimental results are interpreted as practical transmitted-SIR thresholds.
Type
Publication
Proceedings of the Satellite Division’s International Technical Meeting (Online)/Proceedings of the Satellite Division’s International Technical Meeting (CD-ROM)
publication

Abstract & Overview

Recent advances in Joint Communication and Positioning (JCAP) motivate the integration of navigation signals within communication waveforms. This paper investigates a hybrid Direct-Sequence Spread Spectrum (DSSS)–Orthogonal Frequency-Division Multiplexing (OFDM) waveform in which a low-power legacy Global Positioning System (GPS) L1 Coarse/Acquisition (C/A) signal carrying the Legacy Navigation Message (LNAV) message is intentionally overlaid on a Fifth Generation (5G) New Radio (NR) Non-Terrestrial Network (NTN) downlink. The focus is on the Global Navigation Satellite System (GNSS)-side ability to acquire, track, and demodulate the navigation message in the presence of structured 5G interference. The study considers a Medium Earth Orbit (MEO) scenario representative of the SES O3b mPOWER constellation at an altitude of approximately 8000 km. First, MEO Doppler dynamics are characterized using representative orbital parameters, and Monte Carlo (MC) simulations are performed to evaluate LNAV recovery versus Signal-to-Interference-plus-Noise Ratio (SINR) for different transmitted Signal-to-Interference Ratio (SIR) levels. Performance is assessed using navigation-centric metrics, including Bit Error Rate (BER), valid 6 s subframe decoding, valid decoding of the first three subframes, and complete 30 s LNAV frame recovery. The same 35 s reference composite waveform is then transmitted in a continuous loop through the SES O3b mPOWER transparent MEO relay. For each tested SIR level, 300 s of baseband In-phase and Quadrature (I/Q) samples are recorded and processed offline using a MATLAB-based GNSS receiver with 5G Synchronization Signal Block (SSB)-assisted frequency initialization. Simulation results show that, in the considered MEO scenario, Doppler dynamics are moderate and do not constitute the dominant limitation; performance is mainly governed by thermal noise and 5G interference. Experimental results demonstrate reliable LNAV recovery down to approximately -25 dB transmitted SIR, while end-to-end recovery becomes unreliable at -30 dB and below. Since the effective received SINR is not directly available, the experimental results are interpreted as practical transmitted-SIR thresholds.

Publication Metadata

  • Authors: Idir Edjekouane, Alejandro Gonzalez Garrido, Jevgenij Krivochiza, Jorge Querol, Symeon Chatzinotas
  • Venue: Proceedings of the Satellite Division’s International Technical Meeting (Online)/Proceedings of the Satellite Division’s International Technical Meeting (CD-ROM) (2026)
  • Research Areas: 6G-NTN, Satellite Communications, GNSS & Positioning, SDR & Experimental Testbeds
  • DOI: 10.33012/2026.20684
6G-NTN Satellite Communications GNSS & Positioning SDR & Experimental Testbeds