MWG201A Vaisala GPS Processor Unit

The Vaisala DigiCORA MW11A / MARWIN MW12A Automatic Rawinsonde Sets' measurements are based on the use of a free flying balloon-carried radiosonde, transmitting data to the ground station at a frequency of400*406 MHz. Pressure, temperature and humidity (PTU) are measured by sensors in the radiosonde. The speed and direction of wind is determined by means of navigation networks (Navaid) or GPS navigation satellites. The sonde includes a Navaid receiver module or a GPS111 module for this purpose.

The Navaid signals and GPS wind finding data are relayed to the ground station for processing and wind vector computation. The VLF or Loran-C networks or GPS navigation satellites can be used in wind finding. The VLF based wind finding includes Communications VLF and Alpha navigation networks. The VLF and Loran-C methods cannot be used simultaneously.

The standard system configuration includes a directional antenna receiving signals from distances up to 200 km. Also an omnidirectional and portable antenna can be used. A whip antenna with preamplifier and a GPS antenna are needed for monitoring the Navaid networks and the GPS satellites, respectively.

The MW11A/MW12A receives and processes radiosonde signals in real time. The signals are converted to upper-air meteorological data consisting of pressure, temperature and relative humidity. Furthermore the MW11A/ MW12A delivers the collected PTU and wind data to other processing devices such as Personal Computers (PC).

The MW11A/MW12A comprises power supply, ra-diosonde receiver with control processor and signal filters, signal processing units for PTU and wind finding, and Main Processor Unit including program storage. The processor units communicate via asynchronous serial data channels.