The main objective of the project is to develop a novel Low Power Wide Area Network (LPWAN) technology that can meet the demands of the Internet of Things (IoT) applications in network capacity, data rate, and range. The proposed technology is referred to as ZCNET, which modulates data on the Zadoff-Chu sequence in the physical layer and uses ALOHA in the Medium Access Control layer. ZCNET is expected to outperform existing LPWAN technologies such as LoRa, Sigfox, RPMA, Weightless, etc.
The following is a quick comparision between ZCNET and other LPWAN technologies:
| Bandwidth (kHz) | Functioning SNR or Communication Distance | PHY Rate (kbps) | MAC | Capacity (b/s/Hz) | |
| LoRa [5] | 125 | -18 dB | 0.209 | ALOHA | less than 0.0017 |
| Sigfox [2,6] | 192 | similar to LoRa | 0.033 | ALOHA | less than 0.011 |
| RPMA [1] | 1000 | similar to LoRa | 0.06 | ALOHA | less than 0.018 |
| Weightless [4] | 100 | shorter comm. distance than LoRa | 0.625 | mixed | less than 0.025 |
| ZCNET | 120 | -20 dB, better than LoRa | 0.237 | ALOHA | more than 0.042 |
The following are some details and explanations about the comparison:
- The performance of LoRa was obtained by simulation. The performance of ZCNET is obtained with simulation. The capacity values of other technologies are based on the official documents of the companies and are fairly loose upper bounds.
- The network capacity measures the payload received by the Access Point (AP), excluding overhead such as the Medium Access Control (MAC) header and Cyclic Redundancy Check (CRC). In the evaluation, the payload size is only 12 bytes per packet for ZCNET. Larger payload will lead to higher capacity.
- The comparison is for more challenging wireless channel conditions, under which the most robust Modulation and Coding Scheme (MCS) should be used. As an LPWAN is expected to cover a large area, most nodes will likely be under challenging channel conditions.
- Only Weightless has a higher physical layer data rate than ZCNET, which is however at the cost of a shorter communication distance. The SNR threshold of Weightless is -17.5 dB in flat channels, 2.5 dB higher than ZCNET, even when ZCNET was evaluated under more challenging channels. Most LPWAN technologies, including ZCNET, use an ALOHA-style MAC. Weightless, on the other hand, prefers scheduled uplink access, although also offers contended uplink access as an option. The scheduled access will lead to additional complexity, overhead, and latency.
References:
- RPMA Technology for Internet of Things. https://www.ingenu.com/portfolio/how-rpma-works-the-making-of- rpma/.
- Sigfox Technical Overview. https://www.sigfox.com/en/what-sigfox/technology.
- Simulation & experimentation tools for LoRa networks. http://lora.tti.unipa.it/.
- Weightless-P System specification. http://www.weightless.org/about/weightless-specification.
- Olivier Bernard, Andre Seller, and Nicolas Sornin. Low power long range transmitter. EP2763321A1, 2015.
- Minh-Tien Do, Claire Goursaud, and Jean-Marie Gorce. Interference Modelling and Analysis of Random FDMA schemes in Ultra Narrowband Networks. In The Tenth Advanced International Conference on Telecommunications (AICT), pages 132–136, 2014.
- Robert L. Frank, Solomon A. Zadoff, and R. C. Heimiller. Phase shift pulse codes with good periodic correlation properties (corresp.). IRE Trans. Information Theory, 8(6):381–382, 1962.