A new modulation technique based on pulse position modulation and code shift keying
A Time Hopping Pulse Spacing Modulation (TH-PSM) system, which combines the pulse position modulation system with code shift keying, is proposed. The following performances are analyzed; (1) data transmission rate, (2) error rate in a single-user case, (3) error rate in a mufti-user case, and (4) spectral efficiency. Consequently, the data transmission rate of the proposed system is higher than that of the conventional Spread Spectrum Pulse Position Modulation (SS-PPM) system. The proposed system can improve the probability of block error by increasing the number of information bits per spreading code. Moreover; the spectral efficiency of the proposed system is higher than that of the conventional system. The proposed system is more attractive than the conventional SS-PPM system for optical communications; power-line communications, and UWB communications.
pulse position modulation code shift keying spread spectrum pulse position modulation spread-spectrum communications time-hopping spread spectrum