A Novel Anti-interception Waveform in LEO Satellite System

Low Earth Orbit (LEO) satellite communication system is widely used in military deployment, field surveys and anti-terrorism activities, which means the transmitted information often has high value and confidentiality. Therefore, the anti-interception performance of LEO satellite system is significant. Single-carrier Deep Spread Spectrum (SC-DSS) signal has inherent advantage in anti-interception because of its large spreading gain, however, series of problems also exist due to the increased bandwidth. Confronting this, we propose a Non-uniform Multicarrier Deep Spread Spectrum (NUMC-DSS) waveform to serve as a superior alternative of SC-DSS. At the transmitter, NUMC-DSS signal could intelligently adjust the bandwidth, central frequency as well as transmitted power of its sub-band to avoid fixed partial-band interferences and get rid of Doppler code offset. At receiver, NUMC-DSS employs selection combining strategy to counteract the adverse effect of dynamic interference. Performance analysis of NUMC-DSS system has been presented with detailed simulation results. Quantitatively, NUMC-DSS could accomplish accurate reception when the jamming-to-signal ratio (JSR) is equal to 50dB at the cost of 0.4dB loss, while SC-DSS signal fails in reception under the same condition.