Novel Low Duty Cycle Schemes: from Ultra Wide Band to Ultra Low Power

Electronic devices steadily penetrate almost every area of life and transform our surrounding more and more into a dense heterogeneous wireless network. To enable the potential of such a network, a wireless technology with high scalability potential is required supporting devices with ultra low power consumption as well as high data rates. Ultra wideband (UWB) is a promising technology inherently supporting such a system scalability. However, ultra low power communication is still a major challenge. A rigorous low duty cycle operation of UWB impulse radio (UWB-IR) transceivers seems a potential key to ultra low power communication. Thereby, two different approaches are possible. Low pulse rate (LPR) systems realize the low duty cycle by a large pulse repetition period. High pulse rate (HPR) systems achieve the low duty cycle by burst-wise transmission at high peak data rate. Analysis and optimization of these two approaches is the main contribution of this thesis. National authorities impose hard constraints on peak and average transmit power of UWB devices, which makes transmit power an important optimization parameter. Therefore, the impact of peak and average power constraints on UWB-IR signals is analyzed with focus on the Federal Communications Commission’s (FCC) regulations. A joint maximization of peak and average transmit power leads then to modified LPR and HPR schemes with important gains in link margin, coverage and performance. The modified LPRs correspond to a novel type of UWB-IR schemes directly derived from the FCC peak power constraint. They are especially suited for rich scattering environments and drastically increase the TX/RX-scalability in the sense of a tunable trade-off between transmitter and receiver complexity. Moreover, for energy detectors (ED) with a fixed, sufficiently large