An emergency distress beacon is a small battery‐powered device that can be carried on board of ships (called EPIRB = Emergency Position Indicating Radio Beacon), aircraft (called ELT = Emergency Locator Transmitter) and on people (called PLB = Personal Locator Beacon). Once
activated it transmits a signal that is detectable by governmentsearch and rescue authorities. These beacons are regulated by Cospas‐Sarsat, an international organisation for the search and rescue of persons in distress. The Cospas‐Sarsat system uses a constellation of satellites orbiting the globe and a network of earth stations to provide distress alert and location information to rescue teams anywhere in the world. Using the signals transmitted by the beacon, the system calculates its position to within a few km. The beacon's correct operation depends to a great extent on the stability of the reference oscillator that is used to generate the 406 MHz transmitter signal.
Traditionally Oven Controlled Crystal Oscillators (OCXO) have been used for this function. However an OCXO needs significant power and time to heat the internal oven whereas the new Rakon RFPT100 TCXO has a power consumption of only 6mW (typ.) and instantaneously provides a stable output frequency. This results in increased battery life or alternatively allows the use of a smaller battery. The smaller battery reduces system cost and allows future beacons to be smaller and lighter.
The RFPT100 TCXO makes use of Rakon's Pluto™ ASIC which is a fourth‐order temperature compensation chip. The Pluto™ ASIC uses certain patented features, which enables it to achieve the critical medium term stability, previously unattainable