TagAlong: Efficient Integration of Battery-Free Sensor Tags in - PowerPoint PPT Presentation

TagAlong: Efficient Integration of Battery-Free Sensor Tags in Standard Wireless Networks Carlos Pérez-Penichet Diliushi Piumwardane Christian Rohner Thiemo Voigt

Attractive Applications 2

Attractive Applications 2

Battery-free Tag Commodity Device

Battery-free Tag Messages Commodity Device

Battery-free Tag Messages C a r r i e r Commodity Device

Battery-free Tag Messages C a r r i e r Commodity Commodity Device Device

Challenges Energy Latency Interference 4

TagAlong 5

TagAlong • Parallelize interrogations • Share carrier generators when possible • Synchronize tag interrogations 5

System Model A 0 A 3 A 2 A 1 A 4 Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

System Model A 0 A 3 A 2 A 1 A 4 Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

System Model T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Slotframe Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Slotframe Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 6

Tag Interrogation T 1 Host Carrier Generator T 1 Host Carrier Generator 7

Tag Interrogation T 1 Host Carrier Generator T 1 Host TX Carrier Generator RX 7

Tag Interrogation T 1 Host Carrier Generator T 1 Host TX Carrier Generator RX Carrier 7

Tag Interrogation T 1 Host Carrier Generator T 1 RX Host TX TX (req) Carrier Generator RX Carrier 7

Tag Interrogation T 1 Host Carrier Generator T 1 RX TX (reply) Host TX TX (req) RX Carrier Generator RX Carrier Carrier 7

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 8

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Additional Latency Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 8

System Model Edge/Cloud T 1 A 0 A 3 A 2 A 1 A 4 T 2 Must reduce length of tags’ schedule T 3 . . . to minimize energy, latency and spectum overhead Nodes Tags Nodes Tags Nodes Tags A 0 T 1 T 1 T 1 A 1 C C C A 2 T 2 C T 2 C T 2 C . . . A 3 C C C A 4 T 3 T 3 T 3 8

Example T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Sequential Schedule cycle 1 2 3 cycle 1 2 3 A 0 T 1 A 0 T 1 A 1 C A 1 C A 2 T 2 A 2 T 2 C A 3 C C A 3 A 4 T 3 A 4 T 3 9

Example T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 Share carrier generators Sequential Schedule . . . to save energy, time and spectrum cycle 1 2 3 cycle 1 2 3 A 0 T 1 A 0 T 1 A 1 C A 1 C A 2 T 2 A 2 T 2 C A 3 C C A 3 A 4 T 3 A 4 T 3 9

Example T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 TagAlong’s Schedule Sequential Schedule cycle 1 2 3 cycle 1 2 3 A 0 T 1 A 0 T 1 A 1 C A 1 C A 2 T 2 A 2 T 2 C A 3 C C A 3 A 4 T 3 A 4 T 3 9

Example T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 TagAlong’s Schedule Sequential Schedule cycle 1 2 3 cycle 1 2 3 A 0 T 1 A 0 T 1 A 1 C A 1 C A 2 T 2 A 2 T 2 C A 3 C C A 3 A 4 T 3 A 4 T 3 9

Example T 1 A 0 A 3 A 2 A 1 A 4 T 2 T 3 TagAlong’s Schedule Sequential Schedule cycle 1 2 3 cycle 1 2 3 A 0 T 1 A 0 T 1 A 1 C A 1 C A 2 T 2 A 2 T 2 C A 3 C C A 3 A 4 T 3 A 4 T 3 9

Tag Interrogation T 1 T 2 Host Carrier Generator Other Host T 1 Host Carrier Generator Other Host T 2 10

Tag Interrogation T 1 T 2 Host Carrier Generator Other Host T 1 Host TX Carrier Generator RX Other Host TX T 2 10

Tag Interrogation T 1 T 2 Unmodulated carrier as carrier request Host Carrier Generator Other Host avoids collissions in shared carrier generators T 1 Host TX Carrier Generator RX Other Host TX T 2 10

Tag Interrogation T 1 T 2 Host Carrier Generator Other Host T 1 Host TX CG Carrier Generator RX Other Host CG T 2 10

Tag Interrogation T 1 T 2 Host Carrier Generator Other Host T 1 Host TX CG Carrier Generator RX Carrier Other Host CG T 2 10

Tag Interrogation T 1 T 2 Host Carrier Generator Other Host T 1 RX TX (reply) Host TX CG TX (req) RX Carrier Generator RX Carrier Carrier Other Host CG TX (req) RX T 2 RX TX (reply) 10

System Overview 1. Collect network topology in cloud/edge 2. Compute schedule with constraint solver 3. Disseminate new schedule 11

Power 300 per Interrogation Carrier Power per Tag [µW] Sequential 250 TagAlong 200 150 2 3 4 5 6 Number of Tags 12

With Real Testbed Topologies A 1 A 5 A 2 A 4 A 3 A 6 A 8 A 7 13

With Real Testbed Topologies T 3 T 1 A 1 A 5 A 2 A 4 A 3 T 2 A 6 T 4 A 8 A 7 T 6 T 5 13

With Real Testbed Topologies 10 10 Dedicated Slots Necessary Carriers Necessary Slots Testbed 1 Testbed 2 Testbed 3 5 5 0 2 4 6 8 10 2 4 6 8 10 Number of Tags Number of Tags 14

Conclusions 1. First system to coordinate carriers for battery-free devices 2. Implemented and tested in real testbed 3. Optimizes latency, energy consumption and spectrum usage 15

Thank You