Uncovering the secrets of satellite life cycle testing
The aerospace industry is facing its most intense competition since the original space race, with many companies accelerating the development of space exploration capabilities in the hope of achieving greater scale and lower costs while resisting new risks.
Whether it is a High Throughput Satellite (HTS) microwave payload or telemetry, tracking and control (TT&C), every satellite and its subsystem must undergo extremely rigorous testing and verification to ensure that they operate consistently and normally during their mission.
Design and Simulation
Design Optimization
System Integration and Simulation
Production
Environmental Testing
The newly released Satellite Measurement Handbook
Will give you a deeper understanding
Testing throughout the satellite life cycle.
Register now to download the full manual
Today, I will show you what a satellite goes through before it goes into space.
1. Design and Simulation
Ensure through simulation
Smooth sailing from planning to operation
Satellite missions have a unique set of link budget obstacles to overcome. These obstacles include Doppler shift, atmospheric distortion, time delay, extreme temperature fluctuations, high power levels driving amplifiers into nonlinear regions, and the extremely harsh conditions of the space environment. Satellite missions must succeed the first time or fail. Digital modeling of satellite communication systems in such a rapidly changing environment can shorten design time and speed up manufacturing, while increasing mission success and reducing production costs.
Track and Communications Lifecycle Simulation
You can integrate the electronic system-level (ESL) design tools of Keysight PathWave System Design software (SystemVue) with AGI’s System Tool Kit (STK) software to enable engineers to accurately simulate and validate signals in the rapidly changing space environment.
PathWave System Design Software Usage
Simulation with channel dynamics data imported from STK
2. Design Optimization
Through hardware semi-physical testing
Accelerate innovation
The new generation of satellite constellations supports high-capacity, low-latency networks. Such networks will require higher frequencies and greater bandwidth to achieve uninterrupted connectivity around the world. After completing system simulation, accelerate your design process through hardware semi-physical testing. At this time, you need to use the assistance of test equipment to complete the transformation from digital models to hardware models during semi-physical (HIL) testing.
Fast development cycles with PathWave System Design Software
Custom modulation analysis
New proprietary modulation formats used in aerospace, defense, and satellite communications define signals with unique geometries and even asymmetric forms. New transmitters must be thoroughly characterized through measurements such as modulation quality, gain, and flatness.
Use the 89600 VSA as a reference receiver to calculate parameters such as error vector magnitude (EVM), frequency error, etc., using coupling markers between the symbol bits and the IQ or time domain to evaluate the demodulated bits.
Performing Custom IQ Modulation Analysis Using the VSA
Wideband signal analysis for satellite testing
Wideband communications applications such as Ka-, V-, and W-band HTS systems support high data rates. Characterizing amplifiers used in these applications can present unique challenges. Metrics such as EVM, noise power ratio (NPR), gain compression, and phase distortion provide a good indication of how a component will perform in a system. Evaluating these results over the operating power and temperature range can provide a deeper understanding of the amplifier's performance. This solution provides wideband signal analysis with high dynamic range at an affordable price.
Wideband signal analysis test
A Deeper Look at Phase Noise
Communications satellite transponders, whether bent-pipe or digital regenerative, contribute a small amount of noise to the received signal. Satellite transceivers transfer the phase noise of the local oscillator to the mixer output signal during the frequency conversion stage, which reduces the signal-to-noise ratio and increases the bit error rate (BER). Therefore, phase noise is a very important parameter when receiving low-power signals.
N5511A Phase Noise Test System.
50 kHz to 40 GHz
Modulation Distortion Applications
In satellite communication systems, high power amplifiers and low noise amplifiers are key links in the transmission chain to provide the required power to the antenna. In order to maximize efficiency, high power amplifiers such as traveling wave tube amplifiers (TWTAs) and solid-state power amplifiers are often driven close to saturation power, especially in orbiting satellites. When these devices are driven to high power levels, the nonlinear characteristics of the devices will cause distortion of the modulated signal, which may be unrecognizable. The nonlinear response of the power amplifier (PA) directly affects the BER in demodulation. In addition to the poor BER in the channel, the spectrum regrowth caused by nonlinear characteristics will also generate unnecessary power in adjacent channels, making carrier aggregation impossible. Therefore, understanding the linear characteristics of the RF link is critical to ensure the quality of satellite communications.
3. System Integration and Simulation
Testing the entire communication system
The commercial trend of geostationary orbit (GEO) HTS satellite systems and new space low earth orbit (LEO) constellations has brought new challenges to component and system level satellite testing. In order to utilize higher frequencies and larger bandwidths in satellites, more complex testing and characterization are required to ensure that components and systems meet the demanding space requirements. The design, verification and manufacturing of satellite components and systems are inseparable from various test scenarios, for which spectrum analysis and signal generation are the basis of a powerful test system.
Keysight M9384B
and M9383B VXG Microwave Signal Generator
Satellite operators are currently facing the challenge of transmitting more data at higher speeds to more users within the available spectrum bandwidth. To overcome this challenge, operators are using higher-order orthogonal frequency division multiplexing (OFDM) and more complex modulation techniques. As modulation becomes more complex, it becomes increasingly difficult to view waveforms in the time or frequency domain and diagnose signal quality issues. Therefore, modulation accuracy measurements are the best choice for characterizing digitally modulated signals at the system level. With PathWave Vector Signal Analysis (89600 VSA) software, you can measure more than 75 signal standards and modulation types, including satellite communications.
Keysight products enable you to generate and analyze video signals commonly used in direct broadcast satellite systems. These signals include DVB-S/S2/S2X, as well as standard or custom communications signals from DC to V-band and other bands, such as custom IQ, OFDM and 5G signals. These tools are essential for testing the entire satellite system. You can use the same product to perform digital system verification to debug a wide range of signals, whether it is sensor data on a controller area network bus, or cutting-edge, LVDS or SpaceWire/SpaceFibre signaling in digital channelized or regenerative satellites.
Keysight PathWave VSA (89600)
Custom IQ Analysis Software
Test satellite system functionality prior to launch
Satellite, aerospace and airborne radios must meet stringent reliability requirements. Failure of these communication links could result in loss of life-critical data. Test conditions need to closely mimic the operating environment of these radios, not only at the link level but also at the multi-link network level.
PROPSIM Satellite Channel Simulation Solution creates realistic test conditions in the lab for current and future satellite and aerospace communication systems. Create dynamic scenarios and model entire satellite grid constellations to push test standards to their orbital altitudes.
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Simulate extreme RF propagation channel conditions in the lab:
- Long delay Doppler
- Variable delay
- Multipath
- Path loss and rain attenuation
Use PROPSIM to identify and resolve issues early in the development process, thereby shortening development cycles.
Keysight PROPSIM Satellite Channel Simulator
4. Production
Reliable manufacturing process
Repairing space and satellite components in orbit after deployment is not only costly, but also difficult and practically impossible. Therefore, it is critical to maintain the highest quality levels throughout the production process, especially when production scales up.
Establishing production and testing processes that match production speed are both crucial links in production.
5. Environmental testing
Thermal vacuum chamber testing
Equipment used in space applications undergoes rigorous environmental testing to prove that it can survive the extreme conditions of launch and space. Accurately simulating the extreme environmental conditions of space requires testing satellites in thermal vacuum (TVAC) chambers. Testing can run around the clock for several months. Thermal vacuum chamber testing is usually the final test performed, and it is also the most complex and expensive test. Detailed planning is usually required six to 18 months in advance of the test in order to be successful. Testing in a thermal vacuum chamber can cost up to $1 million per day, so it is important to ensure that all measurements are accurate. Thermal vacuum testing helps to identify possible problems, such as outgassing of equipment or materials that could contaminate the satellite environment, design flaws that could cause materials to overheat, and corona (metal vapor arcing) effects that could cause problems in low-pressure environments.
Since satellite testing tasks are extremely complicated, in addition to the above, the following items should be considered for testing and verification before the satellite is launched:
Phased array antenna testing, solar array simulation, satellite power and data bus testing , etc.
Please click the button to view the comprehensive satellite testing plan.
We are committed to helping enterprises, service providers and government customers accelerate innovation and create a secure and connected world. Since the founding of HP in 1939, Keysight Technologies has been operating independently as a new electronic test and measurement company on November 1, 2014. We continue to uphold the same entrepreneurial spirit and passion to start a new journey, inspire global innovators and help them achieve goals beyond imagination. Our solutions are designed to help customers innovate in 5G, automotive, IoT, network security and other fields.
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