Smallsat and CubeSat GPS antennas and GNSS systems

Roundup

CubeSat GPS antennas and GNSS systems are important for effective navigation, coordination, and payload operation. This article gives an overview of antennas that have been developed for nanosatellites, CubeSats and other small satellite form factors that are available on the global space marketplace.

The article begins with a brief introduction to GNSS systems and technology, but if you would like to skip straight to the product listings, please click here.


Introduction

As the range of applications that small satellites can carry out grows, and the systems themselves get smaller thanks to electronic miniaturization, it is increasingly important for operators to be able to access accurate information on their position while in orbit.

Effective attitude control systems enable responsive position fixes in orbit, while communications systems (operating in the X-, S-, or UHF band for example) that connect to the ground also allow satellite operators to take more active, manual control by sending commands to the relevant actuators.

Another option is for a small satellite to make use of the regionally or globally available satellite positioning systems that were primarily developed for navigation on Earth.

The general term for such networks is Global Navigation Satellite System (GNSS) with the Global Positioning System (GPS) being the most well-known.


How satellite GNSS networks operate

GNSS networks are constellations of large satellites in higher Earth orbits; typically Medium Earth Orbit (MEO), at altitudes of approximately 2,000 – 35,000 km, or Geosynchronous Orbit (GSO) at an altitude of 35,786 km.

These constellations produce global signals, across a range of frequency bands, which are picked up by terrestrial GNSS receivers in order to give accurate position information on the ground.

These are the signals used by your car’s satnav, your fitness tracking app when out for a run, or that give live location information on an expected parcel’s delivery.

CubeSat GPS antennas on the global market - car satnav

By adapting ground-based equipment, or by basing new designs for space on them, sub-system manufacturers have developed GNSS receiver systems for satellites that enable navigation information and positing activities on a CubeSat or other small satellite.

There are various structural differences between terrestrial and space-based GNSS equipment.

For example, on Earth such devices are usually built from low-cost, widely-available, commercial-off-the-shelf (COTS) parts. To operate effectively in space such components may need to be adapted to meet the huge thermal and mechanical stresses of launch, radiation-hardened, and made suitable for operating in a vacuum.

CubeSat GPS antennas and GNSS antennas play an important role in the acquisition and translation of the GNSS signal originating at one or more of the existing networks.


GNSS networks

There are several GNSS networks giving coverage across one or more countries and territories. Such networks have been launched by sovereign nations, international organizations, and even private companies.

Global satellite-based navigational systems play a fundamental role in many aspects of industrial activity, military operations, and in consumer products.

Satellite GNSS equipment will often have the ability to connect to multiple networks as needed, in order to extend coverage spatially, and to provide redundancy in the case of one signal being unreachable.

This list below gives an overview of the different networks that a small satellite antenna may be able to interact with:


GPS

The Global Positioning System (GPS) is the most common GNSS around the world. It is owned by the United States government and plays a major role in a wide variety of industrial processes, consumer products, defence applications, and intelligence services.

Note that GPS is often used synonymously with GNSS, but in fact GPS is simply a type of GNSS, in the same way that a reaction wheel is a type of attitude control system.

The GPS is operated and maintained by the U.S. Air Force and more in-depth information is available at GPS.gov, a website maintained by the National Coordination Office for Space-Based Positioning, Navigation, and Timing.

CubeSat GPS antennas enable systems to connect to the primary GPS frequency in the L-Band, between 1 and 2 GHz.

CubeSat GPS antennas on the global market - nasa gps satellite

GLONASS

The Globalnaya Navigazionnaya Sputnikovaya Sistema, or Global Navigation Satellite System, is typically referred to as GLONASS. Initially covering the former Soviet Union, GLONASS now has worldwide coverage and enables satellite navigation systems to use it alongside GPS for faster, more accurate position fixing.

GLONASS is a major part of the Russian space agency Roscosmos’ operations and operates in the following bands:

  • G1 Band: 1589.0625 MHz to 1605.375 MHz
  • G2 Band: 1242.9375 MHz to 1248.625 MHz
  • G3 Band: 1201 MHz

Galileo

A GNSS created by the European Union (EU) through the European Space Agency (ESA) and now operated by the European GNSS Agency (GSA).

Galileo was created to enable Europeans to access a global positioning system independent of GPS or GLONASS, and is freely available worldwide to an accuracy of 1 meter, which can be increased to 1 centimeter in an encrypted form for commercial customers, in the High Accuracy Service (HAS).

Galileo operates in the 1.1 to 1.6 GHz band; a frequency range that is well-suited to mobile navigation and communication services.

Each Galileo satellite is designed to broadcast 10 different navigation signals making it possible for Galileo to offer open (OS), safety-of-life (SOL), commercial (CS) and public regulated services (PRS).


BeiDou

The BeiDou Navigation Satellite System is generally referred to as BeiDou, or simply BDS, and is a worldwide GNSS created and run by the People’s Republic of China. The system was formerly called Compass and began its life by offering regional coverage in China before branching out globally.

Now in its third phase of development, the BeiDou system provides connectivity in the following open service channels:

  • B1I: 1561.098 MHz
  • B1C: 1575.42 MHz
  • B2I: 1207.14 MHz
  • B2a: 1176.45 MHz
  • B2b: 1207.14 MHz
  • B3I: 1268.52 MHz
CubeSat GPS antennas on the global market - beidou
Image credit: beidou.gov.cn.

IRNSS

The Indian Regional Navigation Satellite System (IRNSS) is a regional GNSS owned and operated by the Government of India via the Indian Space Research Organisation (ISRO). It also has the operational name Navigation with Indian Constellation (NavIC).

NavIC satellites use dual frequency bands that provide signals in the L5-band and S-band. The system is designed to provide accurate position information in a primary service area that covers India and a region extending up to 1,500 km from the country’s borders.

It also offers a level of coverage in an extended service area that lies between the primary service area and area enclosed by a rectangle from Latitude 30 deg South to 50 deg North, Longitude 30 deg East to 130 deg East. You can find out more about the system on the ISRO site.


QZSS

The Quasi-Zenith Satellite System (QZSS) is also a regional GNSS, in this case owned by the Government of Japan and operated by QZS System Service Inc. (QSS).

It is designed to complement GPS coverage in Oceania and East Asia and is sometimes referred to as the Japanese GPS. The constellation provides the following signals:

  • L1C/A, L1C, L1S, and L1Sb with a center frequency of 1575.42 MHz
  • L2C with a center frequency of 1227.60 MHz
  • L5 and L5S with a center frequency of 1176.45 MHz
  • L6 with a center frequency of 1278.75 MHz
  • S-band operating in the 2 GHz band

Find out more about the QZSS at the official website here.

More information on each of these GNSS networks is available on the operators’ websites and in this excellent article by Bliley Technologies.

Now that you have been introduced to the use cases for GNSS and GPS connectivity in small satellites, and gained an understanding of the major GNSS constellations which they may access – let’s next take a look at what you may want to consider when selecting a small satellite GNSS or CubeSat GPS antenna for your individual needs.


Understanding your requirements

We recommend a simple four-step approach for the preliminary selection of any new piece of hardware or software for a satellite or other space system.

Note that this is just a basic guide based on what we’ve learned helping hundreds of buyers select products within our marketplace and get rapid responses from suppliers.

It is just meant to help engineers make an initial assessment and shouldn’t replace formalised systems engineering approaches such as the INCOSE Model-Based Systems Engineering (MBSE) CubeSat frameworks.

  1. Specify your currently known mission parameters,
  2. Record all currently known overall design specifications of the system,
  3. Consider the range of technology that will be used in the satellite and in ancillary sub-systems, and
  4. Take into account the key performance criteria of the kind of product you wish to procure.

These criteria are explained in more detail below.


Mission parameters

The first step is to fully understand the currently known mission parameters, including both the critical applications and desirable, but not necessarily essential, objectives.

Typically the more precise mission parameters will only be established later in the process – usually iterated upon in a number of loops by considering the “system of systems.”

But having an idea of what functions your selected technology is likely to need to perform, and on what schedule and duration, will make selecting the most suitable model much easier.

Also consider the launch stresses, testing processes and regulatory compliance that the product will need to go through in order to make it into orbit, as well as any obsolescence procedures once the mission is complete.


Overall design specifications

Next, keep to hand all currently known design information about the entire unit.

This can include the volume, weight, primary structural material and more basic things such as the location, storage and transport arrangements of the major components.

You will need to make sure that the new piece of technology you choose will be suitable for these parameters.


Full range of technology

Once you are clear on exactly what tasks the new product will need to perform and the design characteristics of the satellite or other unit that it will work within, the next consideration is the full range of technology that will sit alongside the product to make sure that everything is compatible.

You may not yet know the entire range of accompanying technology (and you might need to first choose the product model you are interested in in order to make decisions on other components), but make sure you have access to all available technical specifications of sub-systems and structural components that are most likely to be used, as per the current mission plans.

It is important to understand how different sub-systems and components will interface with each other to create a high-performing satellite.

Balancing the available mass, power and volume budgets is also important, which can only be done with a clear plan of which components will be used.

Also consider how the product will work with the planned or existing ground segment to ensure effective data transfer and communication stability.

Now that you have a clear idea of what sort of product is needed for your mission, system, and existing platform setup, the next step is to compare the commercially-available products that meet these criteria according to the most relevant performance metrics.


Key performance criteria for CubeSat GPS antennas

In order to determine the optimal GNSS antenna system for your mission or service it is important to take into account technical specifications, such as:

  • Frequency – choose the most relevant and accessible operational signal band and/or central frequency for your needs (see the section on GNSS networks above for more on the available bands).
  • Antenna gain – a measure of how well the antenna can convert power into radio waves in a specified direction.
  • Polarization – a definition of the polarization of the radiated fields produced by an antenna; this is important for antenna-to-antenna communication. Usually classified as “Linearly Polarized” or “Right Hand Circularly Polarized (RHCP)”.
  • Return loss – ratio of the radio waves rejected by an antenna to those accepted.
  • Axial ratio – ratio between the minor and major axis of the polarization ellipse.
  • Mass
  • Bandwidth – the range of frequencies over which the antenna can operate effectively.
  • Directivity – a measure of how concentrated emitted radiation is, in a chosen direction.

These are just some of the most important attributes that are typically considered when designing or purchasing GNSS connectivity equipment for a small satellite, such as CubeSat GPS antennas. In the section below you can find links to further information and resources on commercially-available products.


GPS and GNSS antennas on the global market

In this section you can find a range of smallsat, nanosat, and CubeSat GPS antennas and GNSS systems on the global market. These listings will be updated when new products are added to the global marketplace for space at satsearch.com – so please check back for more or sign up for our mailing list for all the updates.

You can also view alternative satellite communications and navigational equipment categories for which we have put together the following overviews:

Click on any of the links below to find out more about the antenna systems. You can also submit a request for a quote, documentation or further information on each of the products listed, or send us a more general query to discuss your specific needs, and we will use our global networks of suppliers to find a system to meet your specifications.


A <1U antenna optimized for smallsat missions and designed to cover all GNSS frequencies and the INMARSAT L-band. It has a gain variation of less than 0.6 dBi in all individual sub-bands and features a radome to protect from radiation and electro-static discharges for polar orbit missions.

frequency

1160 — 1610 MHz (L5/E5a, E5b, L2, E6, L1/E1)
1525 — 1559 MHz (Inmarsat L-band)

realized gain

> 0.16 dB @ boresight

polarization

RHCP

return loss

< -13.35 dB

A 3D-printed ceramic antenna designed to provide high radiation tolerance in a <1U envelope. It has been specifically developed to withstand harsh environments without thermal protection due to construction material selection and solder-less feed system.

frequency

1.563 — 1.587 GHz (L1)
1.559 — 1.591 GHz (E1)

realized gain

> 5.5 dBi at boresight
> 4.3 dBi at ± 30°
> 1.1 dBi at ± 60°

polarization

RHCP

return loss

< -20 dB

The NANT antenna has an operating frequency of 1575.42 MHz, bandwidth of 20 MHz and is suitable for use with the NewSpace Systems GPS receiver, a 12-channel hardware-based receiver that utilises an established GPS chipset.

frequency

1575.42 MHz

active gain

≥ 16 dBiC (@ zenith)

polarization

Right Hand Circular (RHCP)

return loss

≤ -5 dB

The piPATCH-L1E1 is a Space-Friendly™ GPS-L1 + GALILEO E1 CubeSat active antenna module designed to provide strong signal reception in space. Featuring an integrated low noise amplifier and SAW filter, matched together with a 35×35 mm patch antenna on a large ground plane.

frequency

1575.42 MHz (GPS L1, GALILEO E1, mount-dependent)

antenna gain

1.5 dBiC (+20 dB LNA)

polarization

RHCP

return loss

-10 dB

The piPATCH-MAX is a Space-Friendly™ GPS-L1 microsatellite active antenna module designed to provide strong signals for GPS satellite reception in space. Featuring an integrated low noise amplifier and SAW filter, matched together with a 35x35 mm patch antenna and large ground plane.

frequency

1575.42 MHz (GPS L1, mount-dependent)

antenna gain

1 dBiC (+20 dB LNA)

polarization

RHCP

return loss

-10 dB

The piPATCH-L1 is a Space-Friendly™ GPS-L1 CubeSat active antenna module that fits all known CubeSat structures with M2.5 mounting holes. It has a frequency of 1.575 GHz / GPS L1, mount-dependent, a return loss of -10dB or better and a 3 dB maximum axial ratio.

frequency

1575.42 MHz (GPS L1, mount-dependent)

antenna gain

1.5 dBiC (+20 dB LNA)

polarization

RHCP

return loss

-10 dB

A miniature version of the Space-Friendly™ GPS-L1 CubeSat Active Antenna module, designed to offer strong signal for GPS satellites reception in space. Featuring a low noise amplifier, RHCP polarization, a maximum axial ratio of 3 dB and a mass of 25 g.

frequency

1575.42 MHz (GPS L1, mount-dependent)

antenna gain

-2 dBi avg. (+20 dB LNA)

polarization

RHCP

return loss

-10 dB

Designed to offer strong signals for GPS satellites reception in space, the product is a smaller version of the Space-Friendly™ GPS-L1 CubeSat Active Antenna module. It features a low noise amplifier, maximum axial ratio of 3 dB, return loss of -10dB or better, and a mass of 40 g.

frequency

1575.42 MHz (GPS L1, mount-dependent)

antenna gain

1 dBiC (+20 dB LNA)

polarization

RHCP

return loss

-10 dB

A TRL 9 Active Antenna with dual GPS L1 + GLONASS bands and up to 50 dBc-Hz SNR on ground for close-to-zenith satellites. The system features a SAW Filter, EMI shielding, and is powered via RF Coax.

frequency

1575.42 – 1602 MHz (GPS L1, GLONASS, mount-dependent)

antenna gain

1 dBiC (+20 dB LNA)

polarization

RHCP

return loss

-10 dB

A space-qualified L-band patch antenna tuned to the GPS frequency bands. The low-profile antenna is designed to provide hemispherical coverage and includes a built-in Low Noise Amplifier (LNA). It is optimized for microsats and smallsats, but can also be mounted recessed on CubeSats.

frequency

1575.42 ± 12 MHz (L1)

antenna gain

5.0 dBiC (90° zenith, free space)

polarization

RHCP

return loss

N/A

An off-the-shelf active antenna for nanosatellites. The antenna is mounted onto a Rogers PCB and is designed for GPS-L1. It is suitable for providing CubeSat platforms with positioning information and is compatible with the ISIS structures.

frequency

1572 — 1578 MHz (GPS L1 / GALILEO E1)

antenna peak gain

5.2 dBi (1575 MHz)

polarization

RHCP

return loss

> 15 dB

The AP.25E has been designed specifically for embedded (inside device) integration with GPS receiver modules where there is a GSM transmitter nearby and risk of interference and saturation.

frequency

1575.42 ± 1.023 MHz

antenna gain

+1.5 dBiC Typ. @ zenith

polarization

RHCP

return loss

N/A


Thanks for reading! If you would like further help identifying a GPS or GNSS antenna system for your specific mission or service please click here to send us a query and we’ll use our extended global networks of suppliers to find the information you need.

Have you noticed that your company isn’t included in this article? Simply send us an email today, and we’d be happy to work with you to showcase your products to the satsearch community!

cubesat
GNSS
GPS
satellite navigation
small satellite
supply chain

related articles

Blog home

Mathieu Bailly 24, February 2021

Cybersecurity for smallsats – 5 key concepts explained

Hywel Curtis 16, February 2021

Smallsat and CubeSat GPS antennas and GNSS systems

Hywel Curtis 28, January 2021

A closer look at the Indian space industry