Preamble Design and Detection for 5G Enabled Satellite Random Access

This paper deals with the crucial issue of random access (RA) preamble design and detection for fifth generation new radio (5G NR) enabled satellite communication systems. In consideration of the characteristics of satellite environment and system compatibility, a long preamble sequence is first constructed by cascading multiple different root Zadoff-Chu (ZC) sequences with large sub-carrier interval in time domain. Then, we further present a multiple sequence joint correlation (MSJC) based one-step timing detection scheme to effectively estimate the value of timing advance (TA), which is capable of flexibly adjusting the number of available ZC sequences involved in correlation operation. The superiority of the proposed method is mathematically validated in terms of robustness to carrier frequency offset (CFO), mitigation of noise, as well as computational complexity. Numerical results in a typical low-earth-orbit (LEO) based non-terrestrial network (NTN) scenario demonstrate that the proposed method, without the pre-compensation of timing and frequency offset, can achieve a remarkable timing performance improvement in comparison with the existing methods.