DASH7 is an ultra-low power wireless technology standard based on ISO 18000-7 that operates at 433MHz. It was developed for the Department of Defense and allied militaries. DASH7 uses very little energy through an RF wakeup mechanism, allowing devices to last for months or years on battery power. It is well-suited for applications involving low latency, low power wireless communication through materials like water, earth, and concrete, such as sensor networks and networks where devices move. More information can be found on the DASH7 website.

1. INTRODUCTION TO
DASH7 TECHNOLOGY
JP Norair
Co-chair, DASH7 Technology Working Group
24 June 2009

2. www.dash7.org
Ultra-low Energy
What is Wireless Data Technology
• Based on the ISO 18000-7 standard
DASH7? • Mandated by U.S. Department of
Defense, allied militaries
• Typical range: 250 m (up to 5 km)
• 433 MHz
• 28 kbps
DASH7 is to ISO 18000-7 • Extendable to 2-hop (ad hoc),
sensor, security, and other features
what WiFi is to IEEE 802.11

3. www.dash7.org
Why does DASH7
use 433 MHz ?

4. www.dash7.org
~1 MHz AM Radio
THERE ARE MANY
FREQUENCIES ~100 MHz FM Radio
Best Signal Strength
Best Data Rate
AVAILABLE 433 MHz DASH7
900 MHz 2G/3G Cellular
Each frequency band has its own strengths
and weaknesses. Low-power, two-way 2 GHz US 3G Cellular
communication typically can only be done
in one of the bands to the left.
2.45 GHz WiFi, Bluetooth

5. www.dash7.org
~1 MHz AM Radio
~100 MHz FM Radio
433 MHz DASH7
433 MHz DASH7
900 MHz 2G/3G Cellular
900 MHz 2G/3G Cellular
2.45 GHz WiFi, Bluetooth
2 GHz US 3G Cellular
Of these bands, there areGHz three can be used in most countries
2.45 only WiFi, Bluetooth
without paying the local government for a license.

6. www.dash7.org
433 MHz DASH7
433 MHz DASH7
900 MHz 2G/3G Cellular
2.45 GHz WiFi, Bluetooth
2.45 GHz WiFi, Bluetooth
And only two that can be used internationally
without a license

7. www.dash7.org
Range
te
Ra
ta
Da
Signa
l Pene
tratio
n
A technology should be used in applications that maximize its strengths.
Technologies without strengths will struggle even if they have no weaknesses.

8. www.dash7.org
2.45 GHz
• High Data Rate • High Power
• Multiple Channels • Short Range
• Streaming Video • WiFi Interference 433 MHz
Range
te
2.45 GHz • Long Range
Ra
• Penetrates Concrete
• Medium Data Rate • Very Short Range (Great Coverage)
ta
• Frequency Hopping • Poor Coverage • Ultra Low Power
Da
• Streaming Audio • Medium Power • No Major Interference
2.45 GHz • Low Data Rate
• Some Antenna Limitations
• Low Power • WiFi Interference
• Poor Coverage Signa
• Short Range l Pene
tratio
n
A technology should be used in applications that maximize its strengths.
Technologies without strengths will struggle even if they have no weaknesses.

9. www.dash7.org
How does DASH7
use so little energy?

10. www.dash7.org
DASH7 HAS RF WAKEUP
Avg:
DASH7 uses a wakeup signal to achieve low
30 - 60
latency, low power, and elegant architecture. µW
The wakeup mechanism requires little overhead
and has a latency of only 2.5 - 5 seconds.
ZigBee has no wakeup and must use an
inflexible scheduling mechanism to
Avg. achieve low power. Recalibrating the
300 - 600 scheduler is a massive power drain, and it
µW must happen whenever devices move.
Source: DASH7 Technology Whitepaper ZIGBEE DOES NOT

11. www.dash7.org
• Months or years of battery runtime,
not days or weeks.
Avg: • Less battery = less cost
30 - 60
µW • Ability to use calculator-style solar cell
• Ability to use “energy harvesting”
• Ability to use flat-flex batteries
WHAT DOES THIS MEAN IN REAL TERMS?

12. www.dash7.org
Is DASH7 Ideal for
your Applications?

13. www.dash7.org
DASH7 USES
Bursty
BLAST
Light data
DASH7 technology takes advantage of the
basic strengths of the 433 MHz band to ASynchronous
provide a reliable, low-complexity solution
to many information-related problems. Transitive
We call this BLAST.

14. www.dash7.org
Perfect For:
• Low Latency AND Low Power
Bursty • Communicates through water, earth, and
even concrete.
Light data • Sensor networks
• Networks where devices move
ASynchronous
Transitive Not Optimized For:
• Streaming Data (e.g. real-time video)
• Other download-centric networks

15. www.dash7.org
DASH7 900MHz Batt-Assist Passive 13.56MHz NFC Passive
May Interfere with Nothing: Frequency independent Cellular Radio Certain DC-DC converters
Restricted, due to interference &
Antenna Placement May be put anywhere de-tuning of cellular antenna May be put anywhere
Min Antenna Size 20 x 20 x 0.05 mm 20 x 50 x 0.1 mm 30 x 30 x 0.05 mm
Active Current 10 mA 50 mA 50 mA
Listening Current 10 µA 10 µA 10 µA
SIM Card Integration Very Possible Active Current may be too high Active Current may be too high
Estimated Range Read/Write: 5 - 250 m (Scalable) Read: 1 m, Beacon: 50 m Read: 1 m, Write: 10 cm
DASH7’s low power, frequency
DASH7 CAN INTEGRATE independence, and light data
characteristics make it easier to
WITH CELLULAR implement into handsets than
passive IT/AIDC technologies are.

16. www.dash7.org
DASH7 HAS AN
HDK
An HDK is available that mates the new
STM32 microcontroller to a 433 MHz radio
and an assortment of sensors:
• Temperature, Humidity, Ambient Light
• MEMS accelerometer
• GPS
The open-source OpenTag library runs on
the HDK to provide DASH7 functionality

17. www.dash7.org
www.dash7.org
End Users
Systems
Integrators
FAQ’s | Whitepapers | How to Join Entrepreneurs
For more information, Academia
Software
Developers
please contact the Semiconductor
ISO 18000-7
DASH7 Alliance.
Licensees
Companies