Wireless Sensor Network Platforms - Datasheets versus Measurements

Wireless Sensor Network Platforms − Datasheets versus Measurements ITG Fachgruppen 5.2.1/5.2.4

Peter Trenkamp [email protected]

University Bremen, Germany 29th of September 2011

Peter Trenkamp: WSN Platforms - Datasheets versus Measurements

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Outline Introduction Datasheet based Evaluation Measurement based Evaluation Serial Interface Radio Frequency Interface Unmodulated Carrier Measurement RF Output Power vs. Supply Voltage Outdoor Line-of-Sight Measurement Conclusion & Outlook


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Introduction

I

Antenna / External antenna connector

I

RF interface

I

Serial interface

I

Microcontroller

I

Other peripherals

Zolertia’s Sensor Mote: "Z1" Peter Trenkamp: WSN Platforms - Datasheets versus Measurements

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Datasheet Evaluation of the Components WSN Mote → Radio Chip RF Output WSN Mote (Max/Min) Sensitivity WSN Mote Link Budget Microcontroller Baud Rate

TelosB CC2420

ZigBit Amp AT86RF230

Z1 CC2420

CM3300 CC2420

0/-25 dBm

20/0 dBm

0/-25 dBm

20/-5 dBm

-94 dBm

-104 dBm

-95 dBm

-103 dBm

95 dB MSP430F1611 115200

124 dB Atmega1281V 57600

95 dB MSP430F2617 115200

123 dB MSP430F1611 115200


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Throughput Measurements on the Serial Interface TelosB

Notebook ZigBit Amp

Z1

Serial Connection (USB)

CM3300

Measurement Setup

Inter-send time in binary milli seconds: IST = 62, 30, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 3 mis Peter Trenkamp: WSN Platforms - Datasheets versus Measurements

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Throughput Measurements on the Serial Interface 100

Carried Traffic [kbit/s]

80

Carried Traffic vs. Offered Traffic for a 34 byte Message Comparison of different Platforms Theoretic Limit TelosB ZigBit Amp Z1 CM3300

60

40

20

00

20

40 60 Offered Traffic [kbit/s]

80

100


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Throughput Measurements on the Radio Interface Sender

Receiver

TelosB

TelosB

ZigBit Amp

ZigBit Amp

Notebook

USB Connection Radio Link Z1

Z1

CM3300

CM3300

Measurement Setup IST = 124, 62, 30, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4 mis Peter Trenkamp: WSN Platforms - Datasheets versus Measurements

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Throughput Measurements on the Radio Interface Carried Traffic vs. Offered Traffic for a 45 byte Message Basestation: Refer to Legend / Sending Mote: TelosB Theoretic Limit TelosB ZigBit Amp Z1 CM3300

100

80



80

Carried Traffic vs. Offered Traffic for a 45 byte Message Basestation: Refer to Legend / Sending Mote: ZigBit Amp Theoretic Limit TelosB ZigBit Amp Z1 CM3300

100

60

40

20

60

40

20

0

20


Throughput Measurements Sending Mote: TelosB

80

100

0

20


80

100

Throughput Measurements Sending Mote: ZigBit Amp Peter Trenkamp: WSN Platforms - Datasheets versus Measurements

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Maximum Throughput (Serial and Radio Interface) WSN Mote →

TelosB

ZigBit Amp

Z1

CM3300

Serial Interface

46.4 kBit/s

23.2 kBit/s

69.6 kBit/s

46.4 kBit/s

Radio IF (receive)

49.4 kBit/s

35.6 kBit/s

82.9 kBit/s

50.8 kBit/s

Radio IF (send)

24.8 kBit/s

82.9 kBit/s

29.5 kBit/s

25.3 kBit/s


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Unmodulated Carrier Measurement

Power Spectral Density [dBm/Hz]

0

Spectrum Analyzer

Spectral Analysis using Unmodulated Single Carrier (USB Powered) Z1 rc0163 Carrier Power (max): -4.6 dBm Z1 rc0149 Carrier Power (max): -4.63 dBm

Center Frequency of Channel 26

10

20

30

40

50 2479.6

TelosB

CM3300

2479.7

2479.8

2479.9

2480.0 2480.1 Frequency [MHz]

2480.2

2480.3

2480.4

USB Powered

Z1

RF Connection (Coax Cable)

Power Spectral Density [dBm/Hz]

0

Spectral Analysis using Unmodulated Single Carrier (1.48V Battery Powered) Z1 rc0163 Carrier Power (max): -4.8 dBm Z1 rc0149 Carrier Power (max): -4.74 dBm

Center Frequency of Channel 26

10

20

30

40

Measurement Setup

50 2479.6

2479.7

2479.8

2479.9

2480.0 2480.1 Frequency [MHz]

2480.2

2480.3

2480.4

Battery Powered Peter Trenkamp: WSN Platforms - Datasheets versus Measurements

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Results of the Unmodulated Carrier Measurement

WSN Mote → RF Output WSN Mote (Datasheet) RF Output WSN Mote (Meas.) Deviation (Log.)

TelosB

ZigBit Amp

Z1

CM3300

0 dBm

20 dBm

0 dBm

20 dBm

-1.03 dBm

N/A

-4.60 dBm

12.52 dBm

1.03 dB

N/A

4.60 dB

7.48 dB


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RF Output Power versus the Supply Voltage Battery Power vs. Output Power using Single Carrier Test Mode (Channel 11) Z1: rc0149 max. Output Power: -1.85 dBm Z1: rc0163 max. Output Power: -1.7 dBm

20

1.2

15

1.4

10

1.6

Output Power [dBm]

Output Power [dBm]

1.0

1.8

Battery Power vs. Output Power using Single Carrier Test Mode (Channel 11) CM3300: 1-1 max. Output Power: 12.3 dBm CM3300: 2-2 max. Output Power: 12.49 dBm

5 0

2.0 5 2.2 10 2.4 1.0

1.5

2.0 Battery Voltage [V]

Sending Mote: Z1

2.5

3.0

151.0

1.5

2.0 Battery Voltage [V]

2.5

3.0

Sending Mote: CM3300


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Attenuated Signal Performance (Wired) RF Attenuator

Computer 192.168.1.2 Network Connection 192.168.1.1 USB Connection

USB Connection

Sending Mote

Receiving Mote A

- 3 dB

- 3 dB

RF Coupler Receiving Mote B RF Connection (Coax Cable)

Measurement Setup


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Attenuated Signal Performance (Wired) Part I 0

20

Sequence Number vs. RSSI with Sending Mote: ZigBit Amp Basestations are shielded by Metallic Box TelosB RSSI (min): -92 dBm Seq Nr (max): 940 Pkt Lost: 4 ZigBit Amp RSSI (min): -91.0 dBm Seq Nr (max): 832 Pkt Lost: 9 Z1 RSSI (min): -91 dBm Seq Nr (max): 896 Pkt Lost: 180 CM3300 RSSI (min): -90 dBm Seq Nr (max): 971 Pkt Lost: 3

0

20

Sequence Number vs. RSSI with Sending Mote: CM3300 Basestations are shielded by Metallic Box TelosB RSSI (min): -92 dBm Seq Nr (max): 894 Pkt Lost: 14 ZigBit Amp RSSI (min): -91.0 dBm Seq Nr (max): 759 Pkt Lost: 9 Z1 RSSI (min): -91 dBm Seq Nr (max): 856 Pkt Lost: 5 CM3300 RSSI (min): -89 dBm Seq Nr (max): 912 Pkt Lost: 1

Rel. Damping of 100 dB


60

40 RSSI [dBm]

RSSI [dBm]

40


60

80


80 Rel. Damping of 50 dB

1000

200

400

Rel. Damping of 50 dB 600 Sequence Number

Sending Mote: ZigBit Amp

800

1000

1000

200

400

600 Sequence Number

800

1000

Sending Mote: CM3300


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Attenuated Signal Performance (Wired) Part II (Sensitivity)

Sending Mote → Receiving Mote ↓ 1. CM3300 2. TelosB 3. Z1 4. ZigBit Amp

TelosB dB

Z1 dB

ZigBit Amp dB

CM3300 dB

0.0 -3.4 -7.6 -19.1

0.0 -4.8 -6.4 -17.1

0.0 -3.9 -9.4 -17.4

0.0 -3.5 -7.0 -19.1


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Outdoor Line-of-Sight Measurement

Measurement Setup Peter Trenkamp: WSN Platforms - Datasheets versus Measurements

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Outdoor Line-of-Sight Measurement RSSI Values Distances vs. RSSI (Mean and Measurement Uncertainty) with Sending Mote: ZigBit Amp Theo. RSSI (min/max): -83.17/-23.09 dBm PTx: 18.0 dBm GTx: 4.0 dB GRx: 5.0 dB TelosB RSSI (min/max): -81.77/-25.93 dBm 30 ZigBit Amp RSSI (min/max): -91.0/-46.72 dBm Z1 RSSI (min/max): -88.37/-38.0 dBm CM3300 RSSI (min/max): -75.37/-26.77 dBm 40 20

50

50 RSSI [dBm]

RSSI [dBm]

Distances vs. RSSI (Mean and Measurement Uncertainty) with Sending Mote: TelosB Theo. RSSI (min/max): -102.87/-42.79 dBm PTx: -1.0 dBm GTx: 3.3 dB GRx: 5.0 dB TelosB RSSI (min/max): -90.97/-55.42 dBm 30 ZigBit Amp RSSI (min/max): -91.0/-78.98 dBm Z1 RSSI (min/max): -90.64/-67.85 dBm CM3300 RSSI (min/max): -88.71/-45.47 dBm 40 20

60

60

70

70

80

80

90

90

1000

50

100

150

200 250 Distance [m]

Sending Mote: TelosB

300

350

400

1000

50

100

150

200 250 Distance [m]

300

350

400

Sending Mote: ZigBit Amp Peter Trenkamp: WSN Platforms - Datasheets versus Measurements

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Results from the Outdoor Line-of-Sight Measurement Range Performance

Sending Mote → Receiving Mote ↓ TelosB ZigBit Amp Z1 CM3300

TelosB Distance

ZigBit Amp Distance

Z1 Distance

CM3300 Distance

112.5 m 97.5 m 82.5 m 135 m

> 409 m > 409 m > 409 m > 409 m

90 m 2.6 m 60 m 60 m

290 m 180 m 240 m 290 m


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Conclusion

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The performance of the 4 platforms differ significantly from each other and from the datasheets

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The CM3300 platform shows the best and the Z1 platform shows the worst overall performance in the mentioned tests

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The ZigBit Amp possesses a weak receiver performance

I

Asymmetric radio link behavior occurs due to the usage of different platforms and different voltage levels


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Outlook

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Evaluation of further nodes

I

Further simulation based evaluation of asymmetric radio links in TOSSIM using Blip 2.0 with MRHOF


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Thanks for your attention!


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