PADS Power Aware Distributed Systems Architecture Approaches

1. PADSPower Aware Distributed SystemsArchitecture Approaches USC Information Sciences InstituteBrian Schott, Bob Parker UCLAMani Srivastava Rockwell Science CenterCharles Chien

2. Instrument a state-of-the-art sensor node to understand and baseline power consumption in current sensor systems. Rockwell WINS is modular: Power Board StrongARM Board Radio Board Sensor Board WINS representative of other sensor nodes in the community. We plan to adapt this node to allow module-level power instrumentation and logging both in the lab and in the field. Sensor Network Baseline

3. Goals Insert a power isolation board between each module. Signals are passed through, power supplies are isolated. Microcontroller provides power monitoring and power control from a host’s serial port (workstation, laptop or iPAQ). Status Four channel instrumentation board completed and was used at SITEX01. Power isolator currently in fabrication. StrongARM Radio Sensor PADS Power Isolator PADS Power Isolator PADS Power Isolator Power Instrumentation Battery Pack

4. Measurement Approach • Measurement Device – Configured to measure the power performance of sensor node in real time • Measurement Data - Used in SensorSim to characterize the nodes’ power performance Measurement Device Sensor Node

5. Research Platform Status • PADS team has been surveying existing sensor node platforms inside and outside community. • mAMPS-1, MIT, StrongARM, ECOS. • Not available to community until Fall 2001. • PicoNode, UCB, StrongARM, ECOS. • Still a candidate architecture. Would have to produce own radio with proper P-A hooks and migrate to • WINS, Rockwell, StrongARM, MCOS/ECOS • Some aspects of design are closed. • WINS 2.0, Sensoria, SH4, Linux • Closed architecture. • ARL CAuS? • Limitation of these nodes is direct dependence on StrongARM (bus master, signaling, control).

6. System Connector IEEE 1386 Mezzanine mAMPS-1 Node Processor Architecture Battery (3.3-5V) DC/DC +5V Boost DC/DC +3.3V Buck +3.3V [1:0] +5V Digital logic supply [4:1] USB IRQ SPI Peripheral Pwr. En. Peripheral Chip Sel. RS232 [15:0] Core Voltage Select Flash [19:2] [4:0] DC/DC +0.9-2.1V Buck [31:0] Core Power DATA StrongARM SA-1110 ADDRESS SPI [19:2] [19:1] MEMORY On-Board Sensor Threshold [31:0] [31:0] Intel GDS1110BB Gain Select

7. System Connector Data Bus [15:0] Signal Ground Address [4:1] Peripheral Chip Select [1:0] Memory Control (~WE, ~OE) RS-232 USB peripheral port Synch. Serial Port (SPI) Peripheral Power Enable [1:0] +3.3V ~IRQ Battery Supply Power Ground 64-pin IEEE 1386 Mezzanine connector

8. PicoNode I Off-the-shelf fully programmable communication/computation node 20 nodes operational; new bluetooth and power boards Orders for nodes due by July 1! • Currently supporting the following efforts • Sensors for smart buildings • Seismic monitoring • Local Positioning research • Ad-hoc networking and media-access research • New physical layers (Bluetooth and others) sensor digital power bluetooth radio

9. ARL CAuS Implementation Proof of concept system achieved 4 orders of magnitude reduction in Size x Weight x Power metric FY99 CAS Gen I FY01 CAS Gen II • Enabled by Adaptive Computing • Supports a wide range of sensors • Move the processing to the sensor head • Low power, high computational throughput • Field upgradeable to support emerging algorithms Courtesy of Bae/ARL

10. AtmelAVR RFMRadio Ultrasound Receiver INT Ultrasound Transmitter UCLA Medusa II • Initial prototype competed: Medusa • Design of Medusa II(using non-SensIT resources) • Longer range ultrasound (15-20m) • Radio Power Control & RSSI circuitry • More computation (Atmel THUMB) • Goal: Hybrid Radio-acoustical localization • use radio for long-range when ultrasound is unable to find a neighbor • Medusa used standalone or as a location coprocessor to sensor nodes

11. Scalable Signal Processing Dynamic Voltage Scaling Power Management for Wireless Sensor Nodes Sensors Radio CPU Dynamic Modulation Scaling Coordinated Power Management Power Manager Real Time Operating System

12. Distributed Sensor Node Approach • Make each module an independent actor on a multi-master serial bus such as I2C (400Kb, 4Mb*). • 87C554 Microcontroller - 16 mA Active, 4 mA Idle, 50 uA Shutdown. • Create common command set for peer to peer communication and control of modules. • Localize specific processing as close to modules as possible (perform energy threshold on seismic board, packet forwarding on radio board, etc.). • A StrongARM may be used for application control and data processing, but could distribute “event handlers” to local microcontrollers and power down most of the time. I2C + Power

13. PADS Research Platform Plan • Focus code development in summer using existing SA1/SA2 development boards, radios, and sensors. • Activate ISI hardware team to invent or leverage existing node stack definition that can be reasonably replicated and deployed. • Build TI TMS320VC5509 DSP processor module. • Build SA2 processor module. • Deploy PADS research platform at ARL Summer ’02 exercise demonstrating 10X power improvement over existing baseline node capabilities.