The satellite industry’s revenue was $208 billion in 2015. There are four segments to the satellite industry: satellite manufacturing, satellite launch equipment, ground-based equipment, and satellite services. Satellite services is by far the largest segment and continues to be a key driver for the overall satellite industry. So, what has a satellite done for you lately? I believe most people would be surprised at just how much modern life depends on satellites services. If the 1381 satellites currently in operation happen to shut down, modern life would be significantly disrupted. Global finance, telecommunications, transportation, weather, national defense, aviation, and many other sectors rely heavily on satellite services. There are three primary segments in the satellite services market: satellite navigation, satellite communications, and Earth observation. Navigation satellites are used for the global distribution of navigation signals and data in order to provide positioning, location, and timing services. Examples of available services are traffic management, surveying and mapping, fleet and asset management, and autonomous driving technology—driverless cars and trucks are expected to be the next big thing. Telecommunication satellites or SATCOM examples are television, telephone, broadband internet, and satellite radio. These systems can provide uninterrupted communications services in the event of disasters that damage ground-based telecommunication networks. Both business and commercial aircraft in-flight internet and mobile entertainment are growing segments of the market. Earth observation satellites are used for the transmission of environmental data. Space-based observations of the Earth promote sustainable agriculture and aid in the response to climate change, land and wildlife management, and energy resources management. Earth observation satellites aid in the safeguard of water resources and improve weather forecasts, so there is a very wide and growing range of satellite services.
So what types of electronic systems are used on satellites? The basic elements of a spacecraft are divided into two sections: the platform or bus and the payload. The platform consists of the five basic subsystems that support the payload: the structural subsystem, the telemetry subsystem, tracking and command subsystems, the electric power and distribution subsystem, the thermal control subsystem, and the attitude and velocity control subsystem. The structural subsystem is the mechanical structure and provides stiffness to withstand stress and vibration. It also provides shielding from radiation for the electronic devices. The telemetry, tracking, and command subsystems include receivers, transmitters, antennas, sensors for temperature, current, voltage, and tank pressure. It also provides the status of various spacecraft subsystems. The electric power and distribution subsystems convert solar into electrical power and charge the spacecraft batteries. The thermal control subsystem helps to protect electronic equipment from extreme temperatures. And finally, the attitude and velocity control subsystem is the orbit control system that consists of sensors to measure vehicle orientation and actuators (reaction wheels, thrusters), and to apply the torques and forces needed to orient the vehicle in the correct orbital position. Typical components of the attitude and control system include Sun and Earth sensors, star sensors, momentum wheels, inertial measurement units (IMUs), and the electronics required to process the signals and control the satellites position.
The payload is the equipment in support of the primary mission. For GPS navigation satellites, this would include atomic clocks, navigation signal generators, and high power RF amplifiers and antennas. For telecommunications systems, the payload would include antennas, transmitters and receivers, low noise amplifiers, mixers and local oscillators, demodulator and modulators, and power amplifiers. Earth observation payloads would include microwave and infrared sounding instruments for weather forecasting, visible infrared imaging radiometers, ozone mapping instruments, visible and infrared cameras, and sensors.
The integration of Analog Devices and Hittite Microwave a few years ago now allows us to cover the dc to 110 GHz spectrum. ADI solutions range from navigation, radar, communication systems below 6 GHz, satellite communications, electronic warfare, radar systems in the microwave spectrum, radar systems, and satellite imaging in the millimeter wave spectrum. Analog Devices offers more than 1000 components covering all RF and microwave signal chains and applications. The combination of Hittite’s full spectrum of RF function blocks, attenuators, LNAs, PAs, and RF switches, in conjunction with Analog Devices portfolio of high performance linear products, high speed ADCs, DACs, active mixers, and PLLs can provide end-to-end system solutions.