Mica, Mica2, MicaZ

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Mica, Mica2, MicaZ

• Katarzyna Bilinska
• Marcin Filo
• Rafal Krystowski
• Supervisor Dr. Waltenegus Dargie

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Agenda

• Motivation
• Architecture MICA, MICA2, MICA z
• Sensing sub-system
• Operating system
• Communication phases
• Test of Mica Mica2

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Motivation

• Elimination of human involvement in gathering
  information
• Smart environment relies first and foremost on
  sensory data from the real world.

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What is Mica?
Mica, responsible for -processing, -storage
-power supply - sending data to base station
Sensing board, responsible for -sensing
Ref. 1
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Why mica?

• Mica wireless platform serves as a foundation for
  the emerging possibilities.
• Nearly a hundred research groups currently use
  Mica nodes
• Mica is created with off-the-shelf hardware
• Mica does not require use of predefined protocols
  (except Mica Z)

Ref. 3
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System architecture
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Logical architecture
RFCommunication
Power management
Processing
Secondary storage
I/OSub-system
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Logical architecture
RFCommunication
Power management
Processing
Secondary storage
I/OSub-system
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Processing sub-system

• Functions
• Application execution
• Resource management
• Peripherial interaction

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Processing Sub-System Mica

• Atmel AVR Atmega 103L (MCU)
• 121 Instructions - Most Single Clock Cycle
  Execution
• Up to 6 MIPS Throughput at 6MHz
• 128k Bytes of In-System Programmable Flash
• 4K Bytes Internal SRAM
• 4K Bytes of In-System Programmable EEPROM
• 53 Programmable I/O Lines
• 3 hardware timers, 1 external UART, 1 SPI port
• Atmel AVR AT90S2313 coprocessor
• 8-pin flash-based microcontroler with an internal
  system clock
• 5 programmable I/O Lines
• Maxim DS2401 (silicon serial number)
• Low cost ROM device
• Unique, factory-lasered and tested 64-bit
  registration number guaranteed no two parts alike
  
• No power requirements (no need for an external
  power source)
• Minimal electronic interface (typically a single
  port pin of a microcontroller)

Used to load the programme into main processor
Used to identify Mica
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Processing Sub-System Mica2, MicaZ

• Atmel AVR Atmega 128L (MCU)
• 133 Instructions - Most Single Clock Cycle
  Execution
• Up to 16 MIPS Throughput at 16MHz
• 128k Bytes of In-System Programmable Flash
• 4K Bytes Internal SRAM
• 4K Bytes of In-System Programmable EEPROM
• 53 Programmable I/O Lines
• 3 hardware timers, 2 external UART, 1 SPI port
• self reprogramable
• hardware multiplier
• JTAG debugging support (real-time, in-system
  debugging)
• Maxim DS2401 (silicon serial number)
• Low cost ROM device
• Unique, factory-lasered and tested 64-bit
  registration number guaranteed no two parts alike
  
• No power requirements (no need for an external
  power source)
• Minimal electronic interface (typically a single
  port pin of a microcontroller)

No need in MicaZ
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Logical architecture
RFCommunication
Power management
Processing
Secondary storage
I/OSub-system
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I/O Sub-System

• Functions
• Interface with sensing boards
• Interface with programming boards
• Program and communicate with other devices

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I/O Sub-System

• The I/O subsystem interface consists of a 51-pin
  expansion connector
• eight analog lines,
• eight power control lines,
• three pulse-width-modulated lines,
• two analog compare lines,
• four external interrupt lines,
• an I2C-bus from Philips Semiconductor,
• an SPI bus,
• a serial port,
• a collection of lines dedicated to programming
  the microcontrollers.

Ref. 3
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Logical architecture
RFCommunication
Power management
Processing
Secondary storage
I/OSub-system
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Secondary storage Sub-System

• Functions
• stores sensor data logs
• temporarily holds program images received over
  the network interface

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Secondary storage Sub-System

• 4 Mb (512 kB) memory organized as 2048 pages of
  264 bytes each
• Single 2.5V - 3.6V or 2.7V - 3.6V Supply
• Serial Peripheral Interface (SPI) Compatible
• 20 MHz Max Clock Frequency
• Two 264-byte SRAM Data Buffers Allows Receiving
  of Data while Reprogramming the Flash Memory
  Array
• Low Power consumption
• 4 mA Active Read Current Typical
• 2 µA CMOS Standby Current Typical

AT45DB041B
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Logical architecture
RFCommunication
Power management
Processing
Secondary storage
I/OSub-system
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Power management Sub-System

• Functions
• regulate the systems supply voltage

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Power management Sub-System (Mica)

• Maxim1678 DC-DC converter provides a constant
  3.0V supply

3 V

• A solid 3V supply is required for radio operation
• Lower voltage can be used to conserve energy
  when the radio is not in use

• Battery produces energy between 3.2V and 2.0V
• In an alkaline battery more than 50 energy lies
  below 1.2 V

• Converter takes input voltage down to 0.8V and
  boosts it to 3.0V

Ref. 3
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Power management Sub-System (Mica2/Z)

• LM 4041 (precision voltage reference )
• Calibrate the battery voltage

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Logical architecture
RFCommunication
Power management
Processing
Secondary storage
I/OSub-system
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Communication Sub-System

• Functions
• Transmit and receive data wirelessly
• Coordinate with other nodes

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Communication Sub-Systemimplementation MICA

• Radio TR 1000
• modulates-demodulates bit
• Send data to processor bit by bit
• AVR (Atmega 103L)
• Protocol proccesing
• Transmission power controler DS 1804
• Hardware accelerators
• Serialization accelerator
• Timing accelerator

What is it? Why do we need them?
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Hardware Accelerators

• I/O alone - recorded a maximum bandwidth of
  10Kbps
• I/O with hardware accelerators - we have been
  able to reach speeds of 50 Kbps

Ref. 4
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Hardware Accelerators Overview
We are using hardware accelerators for
SYNCHRONIZATION
BIT TIMING
BIT SAMPLING

• each hardware accelerators has been built out of
  standard microcontroller functional
  units and rely on I/O programmed to detect
  start symbol

Ref. 4
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Hardware Accelerators Timing Accelerator
- automatically captures the exact timing of the
edge transition of the timing pulse - incoming
signal is automatically sampled every .25 us
- detection of the start symbol gives us an
indication of when the timing pulse will
arrive - once the timing information is
captured, software then uses it to configure a
serialization accelerator that automatically
times and samples the individual bits
Ref. 4
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Hardware Accelerators Synchronization Accelerator
-captures exact timing of incoming packet (within
one clock cycle 250ns) during the
synchronization phase of packet
reception -information available to
application software
Ref. 4
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Communication Sub-Systemimplementation MICA 2

• Radio CC1000
• Modulation demodulation
• Hardware coding-decoding (Menchester)
• Hardware synchronization
• Send data to processor byte by byte
• Power control
• AVR(Atmega 128L)
• Protocol processing

No need of hardware accelerators
No need of DS1804
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Communication Sub-Systemimplementation MICA z

• Radio CC2420 (802.15.4 ZigBee)
• Send data to processor in packets
• Modulation, demodulation
• Protocol processing
• Synchronization
• Coding, decoding
• Error detection, corection
• Acknowledgements

No need of MCU in protocol processing
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Communication
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Radio sub-system architecture
Felxibility Direct access to signal
strength Rich interface Wide filed of
decisions for programmist

• -transmission speed limited by processor speed
• - neccesity of low level programming

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Radio sub-system architecture

• hardware support for synchronization and
  coding/decoding

-limited flexibility
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Radio sub-system architecture

• lack of felxibility

easy to programme 802.15.4 MAC hardware
support 802.15.4 MAC hardware security
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Architecture-summary
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Mica Architecture
Ref. 3
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Sensing Sub-System
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Sensing Sub-System

• Functions
• Sampling physical signals/phenomena
• Different types of sensors
• Photo-sensor
• Acoustic Microphone
• Magnetometer
• Accelerometer
• Sensor Processor Interface
• 51 Pin Connector
• ON-OFF switches for individual sensors
• Multiple data channels

Ref. 1
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Other sensor boards

• Ultrasonic transceiver Localization
• Used for ranging
• Up to 2.5m range
• 6cm accuracy
• Dedicated microprocessor
• 25kHz element

Basic Sensor board Light (Photo), Temperature,
Acceleration, Magnetometer, Microphone, Tone
Detector, Sound
Ref. 1
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Operating system
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Operating system

• The Mica hardware platform has been designed to
  support the TinyOS execution model
• TinyOS is an event based operating system
• TinyOS allows for an application designer to
  select from a variety of system components in
  order to meet application specific goals.

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Communication phases
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RF Wakeup
- it is necessary to put a collection of nodes to
sleep for a long period of time - a radio signal
is used to wake the nodes - RF based wake-up
protocol - nodes have to periodically turn on the
radio and check for wakeup signal
Cost of checking (radio on time) (radio power
consumption)
-power consumption of the radio times the time
the radios is on
Power consumption (checking
frequency) (cost of checking)
-frequency of energy used each time it checks for
the signal times the the check
Avarage wakeup time ½ (checking
period) 1/(2 checking frequency)
-minimize the time a radio must be turned on each
time a node checks for the wakeup signal
-minimize the checking
frequency
Ref. 4
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Localization

• RF localization
• - radio additional sensor
• - radio - analog sensor to detect the strength of
  an incoming signal
• automatically determine the physical position
  of members
• central controller can look at the signal
  strength of each individual bit as well as the
  level of the background noise
• -sender helps the receiver determine the
  reception strength more accurately.

Acoustic localization -an alternative to RF
localization -more accurate
Ref. 4
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Wireless Communication Phases
Transmission
Data to be Transmitted
Encoded data to be Transmitted
Reception
Encoded data received
Data Received
Ref. 4
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Test of Mica, Mica2
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Test of MICA, MICA2

• Assumptions
• measuring packet delivery rate
• The nodes distributed in an ad-hoc manner Impact
  of the different conditions in the absence of
  interfering transmissions
• Nodes placed in a variety of different positions
• near the ground or elevated,
• with or without LOS,
• different levels of obstructions
• (furniture, walls,trees)
• distances from 2 to 50 meters

Mica 1
Mica 2
Ref. 2
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Test of MICA, MICA2

• Experiment facts
• 3 different Environments
• Outdoor habitat reserve
• Urban outdoor environment
• Office building
• 2 Radio type (TR1000, CC1000)
• 6 different Transmission power settings
• Mica from 10dBm to 0 dBm
• Mica2 from 20dBm to 10 dBm
• Packet size
• 25, 50, 100, 150 and 200 bytes
• up to 16 nodes in outdoor and up to 55 nodes in
  indoor experiments
• packet delivery data from more than 300,000
  packet probes
• each node transmitting 200 packets

Ref. 2
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Test of MICA, MICA2
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Test of MICA, MICA2
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Test of MICA, MICA2
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Test of MICA, MICA2-results

• Reception rate , distance

Outdoor Habitat, Mica 2, low outputpower (-10dBm)
Outdoor Habitat, Mica 2, mediumhighoutput power
(1dBm)

• Reception rates vary drastically from 100 to 0
• larger density of data points near the 100 mark
  for almost all the distance range
• links with reception rate lower than 50 appear
  at a larger minimum distance from the source (13
  meters)

• Reception rates vary drastically from 100 to 0
• links with reception rate lower than 50 appear
  at 7m

• increasing the transmission output power
  produces an increase in the number of links with
  good reception rate
• existence of bad links is not completely
  eliminated when increasing the transmission
  output power
• bad links tend to appear at almost any power
  setting used

Ref. 2
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Test of MICA, MICA2-results

• reception rate, distance, power lewel

Outdoor Habitat, Mica 2
Outdoor Urban Mica 2
Indoor office, Mica 1

• General decrease in the reception rate as we
  increase the distance from the source
• Assumptions of packet delivery based exclusively
  on distance from the source can be erroneous in
  practice

Ref. 2
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Test of MICA, MICA2-results

• Reception rate , distance, the same environment

Outdoor Urban, Mica 2 with Low Power (-10dBm)
Outdoor Urban, Mica 2, with High Power (5dBm)
Outdoor Urban, Mica 1, with High Power (-1dBm)

• no significant difference in packet delivery
  between large and small packet sizes, with only a
  small decrease in performance for larger packet
  sizes.

Ref. 2
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Test of MICA, MICA2-results, summary

• General decrease in the reception rate as we
  increase the distance from the source
• there is no clear correlation between packet
  delivery and distance in an area of more than 50
  of the communication range
• Tendency that the higher transmission level the
  higher reception rate
• Mica1 gives worse results due to less
  transmission power

Ref. 2
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References

• 1 www.xbow.com
• Crossbow MPR-MIB Users Manual Revision B, June
  2006
• Crossbow Mica, Mica2, MicaZ Datasheet
• 2 Alberto Cerpa, Naim Busek and Deborah Estrin
  SCALE A tool for Simple Connectivity Assessment
  in Lossy Environments CENS Technical Report 21
  Center for Embedded Networked Sensing, University
  of California, Los Angeles (UCLA) Los Angeles, CA
  90095, USA September 5, 2003
• 3 Jason L. Hill, David E. Culler MICA A
  WIRELESS PLATFORM FOR DEEPLY EMBEDDED NETWORKS
• 4 Jason Hill and David Culler A wireless
  embedded sensor architecture for system-level
  optimization
• 5 Datasheets Atmel 128l, Atmel 103l, Maxim
  1678, RM 4041, DS1804, TR1000, CC1000, CC2420
• 6 Joseph Polastre, Robert Szewczyk, and David
  Culler (Computer Science Department University of
  California, Berkeley) Telos Enabling Ultra-Low
  Power Wireless Research
• 7M.Sc. Thesis by Martin Leopold Power
  Estimation using the Hogthrob Prototype Platform
• 8Deepak Ganesan, Tom Schoellhammer TinyOS
  Platforms and Foundations
• 9Jason Hill (WEBS retreat 1/14/2002) MICA
  Node Architecture

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Thank you for your attention

• Do you have any questions?