Duplex Pulse Interval Modulation

The pulse-position modulation (PPM) method is simple, has the highest power-utilization rate, has a small average-transmission power and error time-slot ratio, and a strong anti-jamming ability; however, it has poor bandwidth efficiency and requires symbol synchronization. Digital pulse-interval modulation (DPIM) has a complex structure, shorter symbol length, higher bandwidth efficiency, and higher power efficiency than on–off keying (OOK) without symbol synchronization.