O1 Upgrade of the platform for channel sounding and data transmission

In the previous project (ENVISERA) we designed a new platform for NVIS data transmission and channel sounding. That platform is completely reconfigurable and is able to both transmit and sound the channel in any bandwidth from 0 Hz to 40 KHz. However, the platform is not as compact as it should be and is not prepared to work autonomously for long time periods during the Antarctic winter. In this working package, we will upgrade the NVIS node in the following aspects:

  • Size reduction, especially in the power amplifier stage.
  • Power consumption reduction, with a better control of the duty cycles and the sleeping stages.
  • Use of solar energy and wind power for an autonomous work during the Antarctic winter.

 

O2 Installation of the testbed between the Artigas Base in King George and Juan Carlos I Base in Livingston

Thanks to the cooperation of the Antarctic Institute from Uruguay (http://www.iau.gub.uy), a permanent radio-link will be established between the Artigas Base in King George Island and the Juan Carlos I Base in Livingston Island. The Artigas Base is operational during the whole year, so the node installed there can be mains-powered during the Antarctic winter. On the other side, the node installed in Juan Carlos I Base needs to be battery-powered. The tests will be done during the campaign 2021-22.
 

O3 Design of compact HF antennas

One of the main drawback of the communication systems using the HF band is the huge size of the antennas. If you try to reduce the size of the antenna, the gain and efficiency will necessarily decrease. However, there are some geometries (loops, boosters) that can reduce the losses of the HF antenna even when you reduce the dimensions to tenths of the wavelength. In order to compensate the antenna losses, we will take advantage of the benefits of the polarization change introduced by the ionosphere in the ordinary and extraordinary wave. Hence, the goal is to design compact HF antennas able to receive both right-hand and left-hand circular polarization waves.

In this working package, we will have the invaluable support of Dr. Jaume Anguera (JA), who is an eminent researcher in the design of antennas for mobile and wireless communications. If we apply antenna reduction techniques from the wireless world to the HF band, we envisage promising results for the NVIS sensors placed in Antarctica. The antennas will be first simulated and then implemented and tested in our field laboratory in Cambrils. In the last campaign we will install them in the Antarctic bases.
 

O4 Study of the NVIS channel throughout the year

In this proposal, we take a step forward in the knowledge of the NVIS channel behaviour. As the link will be operational the whole year, we will be able to sound the NVIS channel in Antarctica where there are no other facilities to do so. In that sense, the researchers of the Ebre Observatory (OE) have expressed an interest about the results of that sounding, which are complementary to the ionograms obtained during the Antarctic summer in the Juan Carlos I. For a better sounding, we will transmit in the whole HF band, from 3 to 30 MHz.
 

O5 Upgrade of the communication capabilities of the NVIS node

At the end of the previous project (ENVISERA), the NVIS node is able to communicate in a 3 KHz bandwidth for a given transmission frequency. The bit-rate may reach 5 Kbps, which is enough for most of the sensors in the market. The node can collect data from other surrounding sensors via Zigbee, a well-known wireless standard for sensors. In this proposal, we will upgrade the communication capabilities of the NVIS node in the following aspects:

  • Automatic selection of the transmission frequency. The NVIS channel is highly variable, with a big amount of interference and channel interruptions. In that sense, a system provided with Automatic Link Establishment (ALE) strategies would be really welcomed. 
  • Significant increase of bit-rate. Preliminary results show that a higher bandwidth up to 30 KHz could be used, thereby increasing the bit-rate allowing low resolution video-conference and a greater number of sensors connected to the node.
  • Polarization diversity techniques to improve the robustness of the communication. By using two synchronised receivers for both the ordinary and the extraordinary wave the robustness of the reception can be significantly increased making transmission power below 1 W feasible. The power consumption of the whole system decreases and the power requirements for the set of batteries during the Antarctic winter fits the current specifications of the Juan Carlos I base.
     

O6 Design of distributed computing and delay tolerant protocols to ensure data transmission in harsh environments

Given the harshness of the Antarctic environment in terms of delay, BER, jitter, etc., a specific reliable data communications protocol needs to be developed in order to enable (1) the proper end-to-end operation of applications running on top of the NVIS infrastructure (e.g., metering data broadcasting, messaging, alerts), (2) multiple users can take advantage of the physical infrastructure concurrently, and (3) an optimal management of all the available computation resources deployed at the Antarctic bases that the NVIS network links. This logical communications layer (also referred to as middleware) will enable a seamless integration of prospective data-driven applications deployed at the Antarctica bases by adapting to the available computation resources and existing physical communications constraints in real-time. Additionally, the development of this middleware will bring a significant advance within the area of distributed computing by combining techniques from Delay Tolerant Networks and Unreliable Distributed Computing.
 

O7 Dissemination of results

We have planned a specific objective dedicated to the dissemination of results. In this proposal, we make three levels of dissemination:

  • Global dissemination: a project web site, with a public and a private zone where all the documents, results and events are registered.
  • National dissemination: our university belongs to La Salle, an international educational institution with more than 1.000.000 students in 80 countries. Only in Spain, there are more than 100 Lasallian centres of primary and high school. In this proposal, we will prepare two workshops addressed to high school students, one about radio-communications in Antarctica and the other about the history of the colonization of Antarctica and the research activities that take place there. A minimum of 30 workshops/conferences will be given by not only the members of the research group, but also by final year students.
  • Dissemination for ham radio operators: as NVIS communications may be interesting for ham radio operators throughout the world, we will publish an open source platform (hardware and software) that ham radio operators can build by themselves. This platform can be connected to their amateur radio stations and allow them to exchange messages, audio-messages and pictures in a very easy way.