Energy-adaptive Pulse Amplitude Modulation for IR-UWB Communications Under Renewable Energy
Impulse Radio Ultra-wideband (IR-UWB) technique has long been recognized for its unique carrierless operation as compared with other communication techniques. The simple and low-cost structure offers great advantages for self-powered embedded wireless systems, in which energy efficiency is a challenging issue due to the fact that most renewable energy sources only offer limited and unstable power supply. In this paper, we present an energy-adaptive Pulse Amplitude Modulation technique for self-powered IR-UWB based communication systems to improve data rate and or time coverage. The basic idea is derived from the fact that domain-specific information in such applications are often available; thus, by jointly exploiting the wireless channel conditions and the non-deterministic characteristics of renewable energy sources, the proposed technique dynamically adjusts the modulation level to enhance the sustainable operation under the unreliable energy supply. Simulation results demonstrate that the proposed technique achieves a much higher data rate and better time coverage than conventional UWB systems. The proposed technique is also insensitive to many practical issues such as the battery aging effect.
ir-uwb renewable energy pam wban transmitter