Ka-band propagation experiment

Ka-band propagation experiment is a national level study administered by Space Applications Centre (SAC), Ahmedabad and NESAC is one of its participatory agency. ISRO is planning to utilize Ka- band radio frequency for communication purpose in India. But Ka- band radio frequency is more susceptible to high signal attenuation during rain and cloudy weather, which will seriously degrade the services. To study the effects of these meteorological parameters on Ka Band radio propagation this experiment has been planned by SAC, Ahmedabad.

The main studies that will be carried out over Indian Tropical region are:

  • Test and verify different rain rate distribution prediction models

  • Comparison of different attenuation prediction models with measurements.

  • Fade slope analysis

  • Test frequency scaling techniques

  • Study of Site diversity concept

  • Study the effects of Hydrometeors

  • Test tropospheric scintillation prediction models

  • Study depolarisation effects especially during thunderstorms.

  • Study Lingering effects

  • Study the effects of clouds

  • Develop Time Series Model of Channel Impairments

The Main outcome of the experiment will be:

  • Validation and selection of a suitable Rain rate distribution prediction and selection of an attenuation prediction model, suitable to be used in different rainfall rate climate zones, over Indian Tropical region.

  • Assessment of performance of “Mitigation Techniques”, based on validation of different FMT algorithms and frequency scaling technique.

  • Selection and validation of suitable tropospheric scintillation prediction model, for Indian region.

  • Understanding of fading effects (from fade slope analysis), depolarization effects and lingering effects in Ka band.

Under this project, a number on equipment like Disdrometer, Microrain Radar (MRR), Rain Gauge, Datalogger etc has been already commissioned and functional. Meteorological data archival and analysis is going. A Dual frequency Beacon Transmitter (20.2 and 30. 5 GHz), Radiometer etc will be installed very soon. A special cabin has been constructed for housing the equipments under the project.