| 1. |
- Carlos, Perez Penichet, et al.
(författare)
-
Augmenting IoT networks with backscatter-enabled passive sensor tags
- 2016
-
Ingår i: Proceedings of the 3rd Workshop on Hot Topics in Wireless. - New York, NY, USA : ACM. - 9781450342513 ; , s. 23-27
-
Konferensbidrag (refereegranskat)abstract
- The sensing modalities available in an Internet-of-Things (IoT) network are usually fixed before deployment, when the operator selects a suitable IoT platform. Retrofitting a deployment with additional sensors can be cumbersome, because it requires either modifying the deployed hardware or adding new devices that then have to be maintained. In this paper, we present our vision and work towards passive sensor tags: battery-free devices that allow to augment existing IoT deployments with additional sensing capabilities without the need to modify the existing deployment. Our passive sensor tags use backscatter transmissions to communicate with the deployed network. Crucially, they do this in a way that is compatible with the deployed network's radio protocol, and without the need for additional infrastructure. We present an FPGA-based prototype of a passive sensor tag that can communicate with unmodified 802.15.4 IoT devices. Our initial experiments with the prototype support the feasibility of our approach. We also lay out the next steps towards fully realizing the vision of passive sensor tags.
|
|
| 2. |
- Di Lascio, Elena, et al.
(författare)
-
Poster Abstract : LocaLight - A Battery-free PassiveLocalization System Using Visible Light
- 2016
-
Konferensbidrag (refereegranskat)abstract
- Most existing indoor localization systems are battery-powered and use the changes in Radio Frequency (RF) signals to localize objects. In this paper, we present LocaLight: a battery-free indoor localization system that localizes objects using visible light by tracking the shadow they cast. By sensing a drop in the intensity of ambient light caused by the presence of a shadow, LocaLight localizes the object. Since the position of the shadow can be predicted, it is possible to localize the object in a sensitive area by carefully positioning the light sensors and the overhead lights. Our initial results suggest that LocaLight achieves an accuracy comparable to many of the state-of-the art solutions that use RF.
|
|
| 3. |
- Hewage, Kasun, et al.
(författare)
-
modBulb : a modular light bulb for visible light communication
- 2016
-
Konferensbidrag (refereegranskat)abstract
- Due to several interesting properties such as large bandwidth and immunity against radio interference, Visible Light Communication (VLC) has caught the attention of the research community. Current efforts are, however, hampered by the lack of open source platforms. We present modBulb, an open, modular light bulb. modBulb is a VLC transmitter that can be customized to the application's requirements. modBulb enables modulation and other processing through an MCU for flexibility and ease of programming or an FPGA for applications that require higher efficiency. Furthermore, modBulb supports several driving circuits to balance the trade-off between energy efficiency and switching noise. Last but not least, the light source itself can be selected according to the application's requirements. We present experiments that demonstrate modBulb's salient properties.
|
|
| 4. |
- Hilmia, Abdalah, et al.
(författare)
-
Poster Abstract:BouKey : Location-Based Key Sharing Using Visible LightCommunication
- 2016
-
Konferensbidrag (refereegranskat)abstract
- Visible Light Communication (VLC) is an emerging communication channel serving as a complement to traditional wireless communication. Visible light has many advantages over other communication channels like its inability to penetrate opaque objects. Securely sharing secret keys is a known problem in computer security. Sharing security keys using Radio Frequency (RF) communication is prone to sniffing attacks. In this paper, we introduce a system called BouKey which uses visible light to share keys. This makes BouKey immune to through the wall sniffing attacks. BouKey divides the key and shares it using multiple transmission bulbs allowing the key to be received in a specific area only. Our initial results show that the characteristics and height of the receiver, as well as the transmission angle play a key role in determining the shape and size of this area.
|
|
| 5. |
- Perez Penichet, Carlos, et al.
(författare)
-
Demo : Passive Sensor Tags
- 2016
-
Ingår i: Mobicom'16. - New York, NY, USA : ACM. - 9781450342261 ; , s. 477-478
-
Konferensbidrag (refereegranskat)abstract
- The sensing capabilities of an Internet-of-Things (IoT) network are usually fixed at deployment. Adding new sensing modalities is a cumbersome process because it requires altering the deployed hardware. We introduce passive sensor tags that allow to easily and seamlessly add new sensors to existing IoT deployments without requiring hardware modifications or additional energy sources. Passive sensor tags employ backscatter communication to generate transmissions that can be decoded by the radio transceivers present in today's IoT devices. Furthermore, unlike recent works, our approach does not require dedicated infrastructure to generate the unmodulated carrier used for backscatter communication. The demo showcases our prototype of a passive sensor tag collecting sensor data and delivering it to unmodified commodity IoT devices using passive 802.15.4 transmissions.
|
|
| 6. |
- Pérez-Penichet, Carlos, et al.
(författare)
-
Do Multiple Bits per Symbol Increase the Throughput of Ambient Backscatter Communications?
- 2016
-
Ingår i: EWSN '16 Proceedings of the 2016 International Conference on Embedded Wireless Systems and Networks. - 9780994988607 ; , s. 355-360
-
Konferensbidrag (refereegranskat)abstract
- Backscatter wireless communications have exceptionally stringent power constraints. This is particularly true for ambient backscatter systems, where energy and wireless carrier are both extracted from weak existing radio signals. The tight power constraints make it difficult to implement advanced coding techniques like spread spectrum, even though such techniques are effective in increasing the communication range and robustness in this type of systems. We draw inspiration from ?code, a previous backscatter coding approach, where data bits are encoded in single-data-bit chip sequences of considerable length to gain robustness. We introduce a new coding technique that encodes several bits in a single symbol in order to increase the data rate of ambient backscatter, while maintaining an acceptable compromise with robustness. We study the proposed technique by means of simulations and characterize the bit error rate and data rate dependencies. A comparison with ?code is drawn and the benefits of each approach are analyzed in search for the best strategy for increasing data rate while maintaining robustness to noise.
|
|
