No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Design and Implementation of Pulse-Based Protocol with Chirp Spread Spectrum for Massive IoT
... It is shown in [2] that APCMA has a higher success probability than CSMA/CA, while [3] shows experiments of high-density communication using 500 APCMA transmitters. In [4], the pulses in the APCMA codewords are enhanced to be modulated by Chirp Spread Spectrum (CSS) to improve reception sensitivity and facilitate long-distance communication. ...
For the realization of an Internet of Things (IoT) with high densities of devices it is necessary that wireless communication protocols are developed that offer (1) low energy consumption, (2) simplicity of encoding and decoding, (3) an asynchronous mode of communication, and (4) an effective but simple method to deal with interference between transmissions. This paper presents the implementation, experimentation, and analysis of a protocol on the MAC sublayer that encodes information in terms of silent intervals between pulses. Based on the representation of patterns of sparse pulses, this encoding has the potential for extremely low power consumption at the transmitter side. It also results in only few conflicts between messages that are broadcast on the same band overlapped in time, while no synchronization between transmitters and receivers is necessary. The protocol is demonstrated experimentally on the 315 MHz band with 100 senders and one receiver configured in a Star topology. Theoretical analysis confirms that the probability of conflicts between messages is low, even if the number of devices increases to the order of ten thousand. This protocol facilitates the implementation of IoT devices that are restricted in terms of hardware and energy resources.
Wireless sensor networks (WSNs) are typically characterized by a limited energy supply at sensor nodes. Hence, energy efficiency is an important issue in the system design and operation of WSNs. In this paper, we introduce a novel communication paradigm that enables energy-efficient information delivery in wireless sensor networks. Compared with traditional communication strategies, the proposed scheme explores a new dimension - time, to deliver information efficiently. We refer to the strategy as Communication through Silence (CtS). We identify a key drawback of CtS - energy - throughput trade-off, and explore optimization mechanisms that can alleviate the trade-off. We then present several challenges that need to be overcome, primarily at the medium access control layer of the network protocol stack, in order to realize CtS effectively.
Asynchronous Pulse-Code Multiple Access (APCMA) has been proposed as a brain-inspired communication protocol based on pulse-like signals (Peper et al, The Brain & Networks, 2018). Encoding data as intervals between pulses, APCMA allows multiple transmitters to transmit pulse trains at arbitrary times. While this typically causes collisions in conventional multiple access protocols, it does not do so in APCMA. Even if pulse trains collide and a receiver receives a mixture of them, they are disentangled by a demodulation algorithm that is based on a spike automaton, which is a type of finite automaton that is designed to recognize specific sequences of pulses. This makes APCMA especially suitable for data multiplexing in a communication system that lacks carrier-sense functionality. In this paper, we apply the APCMA protocol to an electrical power packet routing system. The power packet router lacks carrier-sense functionality, which would be necessary for transmission from multiple sources in a conventional communication protocol. We design and implement the modulation and the demodulation protocols of APCMA on a FPGA in power packet router devices. Our experimental results show that the proposed APCMA-based power routing system can transmit multiple power packets simultaneously without collisions.
To realize massive IoT environments, we proposed Asynchronous Pulse Code Multiple Access (APCMA). APCMA encodes information as intervals between pulses. The sparse signal of APCMA allows a large number of devices to share the limited radio resources. In this paper, we evaluate APCMA with a variety of setting and find that code division of two and duty cycle of 0.01 % can provide 10000 devices with the per-device throughput of about 3.46 bps with 99 % precision. It also is shown that APCMA outperfoms LoRaWAN and CDMA.
Brain-like communication based on spikes has potential advantages in terms of energy consumption, but it is unclear what type of encoding of information allows good robustness to errors. This paper shows how to construct Error Correcting Codes that are particularly applicable to spike-based signals. We adopt an encoding based on Inter-Spike Intervals, and show how the addition of a few “check” spikes makes the codes robust to interference with other spikes. Key in our construction is the use of finite automata that are adapted to recognize specific spike trains. Once the first few spikes are received by such spike automata, they can predict the timing of subsequent spikes, and use this prediction to test whether a spike train is a valid message or not. The proposed spike encoding may find application in wireless sensor networks, in which low energy consumption rather than high data rates is a priority.
Low Power Wide Area (LPWA) networks are attracting a lot of attention primarily because of their ability to offer affordable connectivity to the low-power devices distributed over very large geographical areas. In realizing the vision of the Internet of Things (IoT), LPWA technologies complement and sometimes supersede the conventional cellular and short range wireless technologies in performance for various emerging smart city and machine-to-machine (M2M) applications. This review paper presents the design goals and the techniques, which different LPWA technologies exploit to offer wide-area coverage to low-power devices at the expense of low data rates. We survey several emerging LPWA technologies and the standardization activities carried out by different standards development organizations (e.g., IEEE, IETF, 3GPP, ETSI) as well as the industrial consortia built around individual LPWA technologies (e.g., LORa Alliance,WEIGHTLESS-SIG, and DASH7 Alliance). We further note that LPWA technologies adopt similar approaches, thus sharing similar limitations and challenges. This paper expands on these research challenges and identifies potential directions to address them. While the proprietary LPWA technologies are already hitting the market with large nationwide roll-outs, this paper encourages an active engagement of the research community in solving problems that will shape the connectivity of tens of billions of devices in the next decade.
Unlocking the potential of the internet of things
- J Manyika
- M Chui
- P Bisson
- J Woetzel
- R Dobbs
- J Bughin