An adaptive frequency and time hopping PPM UWB for multiple access communication

Typical ultra wide band (UWB) systems are built to meet quality of service (QoS) constraints under multiple access environment. We propose a UWB physical layer that adapts its number of frequency and time hops to efficiently meet QoS requirements. The proposed adaptive UWB uses side information to know the current QoS and adjusts its number of frequency and time hops accordingly. The system employs adaptive frequency and time hopping pulse position modulation (AFTH-PPM). We have derived an expression for the bit error probability for single user and multiple user synchronous transmitter case under additive white Gaussian noise (AWGN). The bit error rate (BER) performance is evaluated under AWGN with multiple access communication.