Covert wireless communication over uplink satellite-terrestrial network

The emerging deployment of large-scale Low Earth Orbit (LEO) satellite constellations provides seamless global coverage. However, the increasing number of satellites also introduces significant security challenges, such as eavesdropping and illegal communication behavior detection. This paper investigates covert wireless communication over uplink satellite-terrestrial network, focusing on scenarios with warden satellites. By accounting for shot noise generated by ambient signals from terrestrial interferers, the terrestrial transmitter Alice can effectively hide its signal from warden satellites. Leveraging stochastic geometry, the distributions of distances between transmitter and satellites are analyzed, enabling the assessment of uplink performance and interference within a satellite's coverage area. Approximate expressions for detection error probability and transmission outage probability are derived. Based on the theoretical analysis, an optimal scheme is proposed to maximize covert throughput under the constraint of the average detection error probability of the most detrimental warden satellite. Extensive Monte Carlo simulations experiments are conducted to validate the accuracy of analytical methods for evaluating covert performance.