Thoughts on future research

Jan Beutel

Meso-scale energy scavenging

• Renewable energy sources (e.g. solar)• Energy conversion/storage (e.g. supercap, battery)• Energy usage based on user demand

• Software controlled system components• Target very high efficiencies (system-wide)

• Electricity currently has a bright energy future• Potential for energy scavenging to be integrated into

every/many devices

Meso-scale energy scavenging

• Solar is already widely used and successful

• uW class (1 cell), e.g. wristwatches, calculators

• mW class (few cells) is still underdeveloped

• W & kW class (panel based, on- and off-grid), e.g. camping/boats, grid connected

Meso-scale energy scavenging

• State of “few watts” energy scavenging– A few initial trials in WSN community (papers) -> POC– Accurate models are inexistent– Dimensioning and system design largely unclear– Storage options largely unexplored– Systems are always designed in two separate phases

• solar controller and energy consumers

Meso-scale energy scavenging

• Not just an electronic/hw problem

• Storage or usage?• Load balancing?• Accurate models?• Methods & tools for analysis• System design aspects• Control of power/tasks• Limits

Multi-rate low-power wireless

• Example: IEEE 802.11 (Wi-Fi) for WSNs– Gainspan SOC, 2x ARM7, WLAN, LP-modes

Multi-rate low-power wireless

• Industry focuses on ever more bandwidth– e.g. MIMO systems (IIS/ISI ETH Zurich)

Multi-rate low-power wireless• SoCs are finally here• Every (consumer) device has multiple interfaces

• Our niche would be on efficiency, adaptivity• Large dynamic range from bits/minute to MBytes/sec• Trade-off of many different parameters (latency, protocol

features, redundancy)• Relatively easy to prototype on multi-radio systems

• Related work: Bahl (wakeup radio), industry, communication community …