An adaptive UWB modulation scheme for optimization of energy, BER, and data rate

For many networks, different types of data require various QoS (quality of service) constraints such as bit error rate (BER), data rate, or energy dissipation. High data rate, low power dissipation, and simple RF circuitry make ultra wideband (UWB) an attractive technology to meet many QoS requirements. Typical UWB systems are built to meet QoS constraints even under the worst environmental conditions, although the worst environmental conditions occur infrequently. To prevent this waste of resources, we propose a UWB physical layer that adapts its modulation scheme to meet QoS requirements efficiently. The system employs m-ary PPM and adapts its pulse repetition interval (PRI) and/or the number of bits per symbol (log₂m). Compared to a non-adaptive system, the adaptive system can improve BER up to 50%, energy by 60%, or data rate by 260%.