GNSS Devices: The Key to Position Sensing
One of Epson's sensing solution technologies is position sensing, and our key devices are our Global Navigation Satellite System (GNSS) devices. Epson's GNSS devices achieve revolutionary low power consumption and high precision and miniaturization. They are also compatible with Japan's "Michibiki" Quasi-Zenith Satellite System and boast a high reception sensitivity.
Epson began developing position sensing device technology in 1996, when it started developing low power consumption GPS technology (GPS: Global Positioning System). Then, in 1998, we released the Locatio. This was a GPS-equipped PDA, which could be considered the prototype of today's smartphones. Afterwards, in the mid-2000s, we began supplying GPS modules to major domestic mobile phone manufacturers. Through this and other activities, we have worked hard to develop GPS and GNSS technology for roughly a quarter of a century.
GNSS devices that correctly detect position using satellite radio waves
GNSS is a system originally created for military use to determine the current position on the
Earth's surface by using radio waves from satellites. Today this technology is included in various products
ranging from car navigation systems to airplanes, smartphones, watches and cameras. And it has become an
essential element of people's lives.
GNSS devices constantly receive signals (GNSS radio waves) from four or more satellites. Position information about each satellite is obtained from the signals, and the distance to the satellite is calculated from the time it takes the signal to arrive. From this, the device knows that it is somewhere on the surface of a sphere centered around the satellite from which the signal was received. By combining information received from multiple satellites, it can measure its current position on the surface of the Earth.
Accurately measuring the distance to a satellite requires measuring the precise time it takes for a signal to arrive. Therefore, the satellites are equipped with high-precision atomic clocks that have a measurement error of within one second in every 100,000 years. GNSS devices employ high-precision clocks, which utilize crystal oscillators, and minimize measurement error by carrying out measurements with compensation for the time it takes signals to arrive from four or more satellites.
Epson's position sensing technology contributes to safety and security
Epson position sensing technology achieves high precision and low power consumption via
multiple technologies. These include high frequency analog technology that we've cultivated through
semiconductors, algorithm software technology that includes signal processing technology and position
calculation technology, low power consumption Digital Temperature Compensated Crystal Oscillator (DTCXO)
technology specialized for position sensing, and Smart Duty control technology that provides automatic
control in accordance with the satellite signal reception environment.
Direct signals from the satellite, and indirect waves occurring due to reflection off things such as buildings in downtown high-rise areas, can cause multi-path errors. Epson technologies employ original algorithms to assess and optimize these signals, and significantly improve reception accuracy.
In addition, these technologies are used at Epson to identify the time zone for the current position using GNSS satellite radio waves alone. This has given birth to the Trume, an original analog watch that always displays the correct time.
In the future, we anticipate GNSS technology being applied for industrial and business uses, such as to prevent loss or theft of construction equipment, heavy machinery, shipping containers and the like, by equipping them with GNSS devices that will allow their position to be known. We also foresee small, easy-to-use dedicated consumer devices for preventing crime or watching over children.
In addition to GNSS devices, Epson has numerous sensing devices that utilize its core proprietary sensing technology. We have also analyzed big data gathered through sensors over many years to accumulate a vast amount of data and algorithms. Epson intends to use its family of sensing devices and the new value obtained through analyzing big data to create an algorithm platform. This will form the core of our efforts to deliver high precision position information through position sensing technology, and thereby help to create a safe, secure and sustainable society.