Society for Applied Microwave Electronics Engineering & Research
Ministry of Electronics & Information Technology
Government of India
Signal Processing and Navigational Electronics
(Core R&D Activity)
- 1680 MHz Radio Theodolite
India Meteorological Department (IMD) has sponsored the development of one unit of Radio Theodolite at 1680 MHz. These ground based systems are used for tracking radiosonde (RS). The Radiosonde system consists the atmospheric sensors and UHF transmitter which are flown with gas filled balloons for regular upper air monitoring. These RS units are tracked by ground based RT systems to determine the location of the RS and hence compute the wind velocity. The Radio Theodolite system has a steerable parabolic dish of dia 2.1m. The dish is mounted on a rugged platform which is capable of sustaining the wind speed of 140 Km.hr-1. The electronic system of the RT performs mono-pulse tracking with automated steering. It also has capability of automatic Frequency Control (AFC). With advance a graphical user interface (GUI) and modern data processing features the system provides a state-of art solution to the radio-sonde observations. The performance of the system was technically evaluated by the expert review committee. The system was installed at RSRW station at Santacruz, Mumbai for field trials and performance evaluation
- GPS Radiosonde
Global Positioning System (GPS) receivers are now available at affordable prices. As a result of this some of the Radiosonde (RS) units have on-board GPS receiver. The onboard GPS receiver generates accurate, high resolution positional data of the radiosonde balloon during its ascent. This balloon positional data is used for computing high Resolution Vertical Wind Profile of the atmosphere. SAMEER has successfully developed and demonstrated the GPS Radiosonde at 1680 MHz. SAMEER has signed an MoU with IMD to transfer the GPS Radiosonde technology for use in their Upper Air Data Network.
- Sun Photometer
A five channel hand held, filter photo-detector based sun-photometer has been successfully developed to estimate total columnar Ozone, water vapour and aerosol optical thickness of the atmosphere over the observation location. The low cost, portable sun-photometer is an important tool for the research and academic studies of the atmospheric aerosols, ozone and water vapour. The study of these parameters enable scientist to improve models for weather and air quality forecasting and for climate change prediction. The Department of Science and Technology (DST) has sponsored this project for the development of 5 prototype units of the Sun photometer.
- Signal conditioning card for the Radiometer-sonde and Ozone-sonde
India Meteorological Department has sponsored a project for the development of Ozone-sonde and Radiometer-sonde. These are special type of radiosonde carry sensors for the measurement of the ozone and the terrestrial radiation. These units require accurate instrumentation for the sensing circuitry and advanced statistical processing method the data.
The automatic data acquisition and processing software for ozone sonde and radiometer sonde has been completed. The special test flights for Radiometer sonde were taken in Jan 2010. Similar test flights for Ozone sonde are planned in July 2010. After successful trials, signal conditioning cards and PC based software packages would be handed over to IMD for conducting operational observations.