Ultra Low Power Transmitters For Wireless Sensor Networks

Ultra Low Power Transmitters for Wireless Sensor Networks

Ultra-Low Power Wireless Technologies for Sensor Networks

transconductance e?ciency of all critical devices in order to reduce the n- essary bias current. However, reducing the current density also results in a severely decreased device f . An optimization of the current density is re- T quired to provide the correct balance between transconductance e?ciency and bandwidth. Plots such as Figure 2. 1 are useful tools for designers when choosing appropriate transistor bias points. Technology scaling allows greatly increased f realization for a given IC. Thus, weak inversion biasing for RF T design will become increasingly useful in future technology nodes. Throughout this work, the IC of critical transistors will be discussed. Most of the RF devices are biased in moderate to weak inversion to achieve enhanced transconductance e?ciency and reduced bias current. 2. 2 MEMS Background The relatively new ?eld of Radio Frequency Microelectro Mechanical Systems (RF MEMS) provides unique opportunities for RF transceiver designers. This section provides background on RF MEMS and provides insight into the - portunities presented by these new technologies. The ?eld of RF MEMS - cludes the design and utilization of RF ?lters, resonators, switches, and other passive mechanical structures constructed using bulk processed integrated c- cuit fabrication techniques. To date, these devices have been commercially used as discrete board-mounted components, primarily used to enhance the miniaturization of mobile phones. However, RF MEMS components have the potential to be batch fabricated using existing integrated circuit fabrication techniques.

Architectures and Synthesizers for Ultra-low Power Fast Frequency-Hopping WSN Radios

Wireless sensor networks have the potential to become the third wireless revolution after wireless voice networks in the 80s and wireless data networks in the late 90s. Unfortunately, radio power consumption is still a major bottleneck to the wide adoption of this technology. Different directions have been explored to minimize the radio consumption, but the major drawback of the proposed solutions is a reduced wireless link robustness. The primary goal of Architectures and Synthesizers for Ultra-low Power Fast Frequency-Hopping WSN Radios is to discuss, in detail, existing and new architectural and circuit level solutions for ultra-low power, robust, uni-directional and bi-directional radio links. Architectures and Synthesizers for Ultra-low Power Fast Frequency-Hopping WSN Radios guides the reader through the many system, circuit and technology trade-offs he will be facing in the design of communication systems for wireless sensor networks. Finally, this book, through different examples realized in both advanced CMOS and bipolar technologies opens a new path in the radio design, showing how radio link robustness can be guaranteed by techniques that were previously exclusively used in radio systems for middle or high end applications like Bluetooth and military communications while still minimizing the overall system power consumption.