If there were n healthy satellites above the mask, a receiver with k channels would need to evaluate Nopt geometries, where Nopt is given by a straightforward combination, as shown in Equation .
However, it is easy to see that the amount of geometries to evaluate can easily become infeasible as n and k change.
While KF can be utilized as an offline or online algorithm based on what the optimization objective is (i.e., what the system model from Equations and represents), in practical applications concerning autonomous vehicles, it really is typically found in an online fashion.
Although not always in the LEO context, the most typical examples of KF implementations in neuro-scientific autonomous vehicles are sensor fusion and/or trajectory tracking .
The method typically does not consume significant resources from the machine and adds negligible delay to the operation; thus, it remains a highly utilized method, but not always for optimization but instead as a method for estimation, tracking, etc.
For the simulations, we considered a rural scenario with a Line of Sight condition.
Which means that direct vision between user receiver and satellites was achieved, as well as low density of scatters and multipath components.

discuss existing limitations of high-speed scenarios for autonomous vehicles.
One limitation in today’s terrestrial technologies with regard to autonomous vehicle services may be the requirement for ubiquitous and seamless coverage, which should be as near 100% as possible.
To be able to address this challenging limit, satellite-based networks, such as leo, together with their integration with terrestrial networks, have begun being investigated in the literature, e.g., in .
The authors in considered a Speech Emotion Recognition application for autonomous vehicles, for which a 5G-enabled Space-Air-Ground Integrated Network was designed.
As such, the work explored ground, space, and user segments for the use of interest, nonetheless it only provided the look and architecture of the network, without explaining the related optimization processes.
However, the user-segment optimization linked to SER was covered in great detail, because they explained the Artificial Intelligence model used for acoustic data modeling.

High-speed Scenarios Based On Leo Satellites For Future Autonomous Vehicles

We will add a discussion concerning the known design parameters of these systems later inside our paper.
Use of the Earth’s orbits, specifically low-earth orbits , has significantly increased in recent years.
This follows rapid growth in institutional applications and in the commercialisation of space activities, driven by lower launch costs and high expected returns in the data-intensive downstream segments.
At the same time, space debris are accumulating and may reach uncontrollable levels unless effective action is taken.

To better model the orbits, a Simplified Deep Space Perturbation model was used along with the Matlab Satellite Communication Toolbox.
The SDP4 model accounts for the effects of the oblateness of the planet earth and atmospheric drag effects in the satellite orbit, among other effects.
The main optimization problem with regards to the ground segment refers to the optimization of the number and placement of ground stations all over the Earth so that they are in a position to offer good monitoring, management, and control of most LEO satellites in the sky.
However, currently, there are hardly any studies in open access describing optimization methods for LEO ground segments.
In contrast, many such studies exist for MEO GNSS systems, in fact it is to be expected that a number of the optimization mechanisms previously proposed for GNSS are also applicable in the LEO context.
Consequently, in this section, we will present the metrics and methods that have seen successful in either case.

The major advantages of absolute station keeping reported in in comparison to relative station keeping are a priori Sat position estimates, better quality control, less propellant requirements, less complexity, and cost.
It also highlights that for autonomous station keeping, the absolute station keeping is better since it is implemented with a more substantial sequence of small ΔV maneuvers, rather than few small impulsive maneuvers.
Sat station keeping can be achieved through low thrust maneuvers or impulsive maneuvers.
Both maintenance schemes and propulsion systems are widely studied for LEO constellations.
If we aim to achieve full automation in high-speed cases, future networks of autonomous vehicles could have stringent requirements regarding communications, positioning, and sensing characteristics, which are not yet fully met by current cellular and IoT technologies.
A listing of these stringent requirements is given in Table 4, as well as example studies from the literature which have addressed these challenges to some extent and offered various solutions to them.

Soyuz Launches 34 Oneweb Satellites

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More recently, in August 2021, Telesat announced that it expects to receive a CAD1.44 billion ($1.17 billion) investment from the federal government of Canada to aid Telesat Lightspeed.
The venture was launched in Xiongan, the “New Area” situated 100 km southwest of Beijing, established in April 2017 as a development hub.
In September 2021,

  • “Having a flag behind us is really helpful, and Bharti brings incredible telco-know-how, execution capability and scale.”
  • The same day OneWeb announced that it had signed its first two client agreements marking the beginning of its commercialization.
  • This brings OneWeb’s total in-orbit constellation to 358 satellites—just over half of its planned 648 LEO satellite fleet.

This would have considerable negative impacts on the provision of a number of important government services and would almost certainly also curb economic growth and additional development in the area sector.
The societal costs will be unequally distributed, with some rural regions harder hit, given their growing reliance on satellite communications specifically.
Regions which have limited surface observations for, e.g. weather forecasting, would also be disadvantaged.
On Friday from the spaceport in Kazakhstan, OneWeb, a telecommunications company with its headquarters in London, launched 34 satellites into space.
The space-segment optimization, as mentioned above, includes all optimization steps that take place within the satellite constellation, and such optimization steps can happen in multiple layers.

In Europe, the EU supports a Consortium for European Space Surveillance and Tracking , with Consortium members providing surveillance and tracking services to all or any EU countries, institutions, and public and private operators.

Noise Complaints Help Bring Down Launch Startup Spaceryde

Gingiss said about 50 % of the parts on each spacecraft result from North America, and the other half come from Europe.
Like OneWeb, SpaceX says it could start serving high-latitude regions the Starlink broadband coverage this season, accompanied by the inauguration of global service.
The last group of OneWeb satellites flew off the Fregat’s dispenser around 3 hours, 45 minutes into the mission.
About an hour later, officials received telemetry data confirming the deployment of most 34 satellites.
First, two of the 325-pound (147.5-kilogram) satellites separated from the top of the cluster.
The remaining 32 spacecraft separated in sets of four at intervals of around 20 minutes, with maneuvers by the Fregat’s smaller attitude control thrusters among to guarantee the satellites did not collide.
The main engine of the Fregat upper stage ignited 2 times to place the 34 OneWeb satellites right into a targeted polar orbit roughly 280 miles above Earth, having an inclination of 87.4 degrees to the equator.

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