Abstract: In order to enhance the performance of low earth orbit (LEO) satellite navigation service, this paper reviews the current research status of LEO signal waveforms, which compares and analyzes the structure of LEO navigation signals based on linear frequency modulation (LFM), and investigates their multiple access implementation and parameter estimation methods. The design approach utilizing LFM signals modulated by pseudo random spread spectrum codes represents an effective signal combination method. Based on this, the performance of multiple access and the accuracy of parameter estimation can be significantly improved.