How does satellite communication work?

March 9, 2023

The contemporary lifestyle can only be conceived thanks to satellites. Their impact on our daily lives is enormous as satellite communication systems provide transmission and reception services for television, telephony, radio, and data, resources on which our society is built.


What is the origin of these satellites?

The Russian satellite Sputnik was the first satellite launched into space. It was an aluminum sphere with a diameter of 58 centimeters and weighing just over 80 kilos with four long and thin antennas. Its mission was to obtain information about the upper layers of the atmosphere as well as the electromagnetic field of our planet. 

This milestone was achieved in 1957, and just five years later, Nasa launched the first telecommunications satellite in history, Telstar. Also spherical in shape, with a diameter of 87.6 centimeters and a weight of 77 kilograms, this satellite successfully transmitted through space the first television images, including the first transatlantic transmission, telephone calls, and telegraph images.

The success of both satellites, in the context of the Cold War, meant a change in humanity, which not only conquered a part of space but also meant a great advance in preventing natural catastrophes and achieving communication between faraway points.


Why is satellite communication so important?

Currently, there are some 5,600 satellites orbiting around our planet. These are constantly relaying analog and digital signals carrying voice, video, and data to/from one or more locations worldwide. Most of them, about 3,000, are in Low Earth Orbit (LEO), where the communications or remote sensing satellites are located. Elon Musk’s Starlink satellites, or those of SpaceX, are some examples of this type. 

This system allows a wide variety of simultaneous services: multichannel television, telephony, data, and interactive multimedia services. These technologies and advances have favored the progress of science and society, bringing closer and democratizing access to information and communication.

In addition, there are Medium Earth Orbit, High Earth Orbit, Geosynchronous Orbit, Geosynchronous Transfer Orbit, and High Heliptic Orbit satellites, which serve, among other functions, to enable navigation systems, observation of the planet, assist other satellites or geo-detection.


Communication satellites: characteristics of this technology

Communication satellites are vital for connecting different points on Earth. Satellite communication has two main components: the ground segment, which consists of transmission, reception and fixed or mobile auxiliary equipment, and the space segment, which is mainly the satellite itself.

Telecommunication satellites transmit radio frequency signals from the Earth to the satellite (uplinks) and retransmit them from the satellite to the Earth (downlinks).  Satellites use different types of frequency bands in order to function correctly. Among them are the L Band (1-2 GHz), C Band (4-8 GHz), X Band (8-12 Ghz), Ku Band (12-18 GHz) or Ka-Band (26-40 Ghz), in which BeetleSat, the next generation backhaul LEO Satellite Constellation is located and in which ARQUIMEA participates in its development.

The communication payload of a satellite is composed of a repeater and an antenna system in charge of receiving the uplink signals, filtering them to eliminate noise, and lowering the signals from the frequency to the transmission band. It is then responsible for separating the broadcast channels, which it amplifies and reassembles for transmission to Earth.


What is Spain’s role in the development of satellite communication?

The Spanish space industry  has experienced a great growth in the last decade and is currently present in satellite telecommunication programs worldwide supplying equipment to the main manufacturers.

The telecommunications market is very competitive, so the investment in R&D&I is the differential mark among the many companies involved in this sector. In Spain, some of the main components produced are:

– Radiofrequency equipment: filters, input multiplexers (IMUX) and output multiplexers (OMUX), low noise amplifiers (LNA), frequency converters, couplers, waveguides, diplexers…

– Platform: structures, thermal control, cabling…

– Antennas: reflectors, feeders, horns, active antennas…


BeetleSat, a constellation of satellites developed by ARQUIMEA

ARQUIMEA has been over 17 years developing, engineering, and producing qualified components and systems for space use and essential and highly reliable applications. During these years, we have built more than 30,000 parts supplied within the framework of ESA and NASA missions and to key satellite operators.

Currently, ARQUIMEA is working with NSLComm, an Israeli space technology company, to develop BeetleSat, the next-generation Ka-band LEO (Low Earth Orbit) satellite constellation for cellular backhaul applications. This constellation will enable a universal, secure, low-latency, cost-effective, multi-gigabit, low-latency telecommunications platform.
Discover more about ARQUIMEA’s space projects by checking our case studies.