CURRENT ITU-R SG3 INTERESTS
Working Party 3J
· Radio noise models at VHF and higher, especially for impulsive noise
· Variations of ground wave field strengths at LF/MF over urban terrain, and with season
· Free space optical propagation models
· Ground scatter at 18-48 GHz especially measured data for links from satellites, high altitude platforms and aircraft
· Statistics on the duration of rainfall events for dynamic effects of rain attenuation
· Building and vehicle entry propagation losses above 100 GHz
· Propagation through vegetation - data needed
· Risk analysis and variability statistics in relation to communication links
· Effects of building materials on radio propagation
· Effects of refraction on Earth-space propagation paths (Rec. ITU-R P.834)
Working Party 3K
· Point-area path specific prediction methods in the range 1-3 GHz where terrain profiles are available
· Short range - indoor and outdoor propagation data – delay profiles fro broadband – angular spread for MIMO
· Wireless broadband at millimetre wavelengths
· Ultra Wide Band in the frequency range 1-10 GHz
· Propagation data for land mobile services
· Use of digital terrain maps for propagation predictions
Working Party 3L
· System performance and reliability for digital modulation techniques at HF
· Model of delay and frequency spread caused by ionospheric features on HF wideband (100 kHz) transmission channels
· Amplitude and phase scintillation of trans-ionospheric signals, their frequency dependence, cumulative statistics, and geographic modelling for low and high latitudes
· Satellite to satellite propagation modelling through the ionosphere and troposphere (eg earth grazing paths)
· The optimum use of ionospheric models in automatic channel evaluation systems
· Power Line Transmission (or Broadband Powerline) emission characteristics
· Variability of ionospheric conditions and predictability of effects on HF systems
Working Party 3M
· Short-delay multipath in aeronautical communication and navigation systems on landing approach
· Prediction method for free space optical propagation
· Propagation prediction associated with land mobile-satellite services (Rec. ITU-R P.681)
· Evaluation of interference signals and coordination distance for earth stations (Rec. ITU-R P.452 and P.620)
· Earth-space propagation prediction (Recs. ITU-R P.618 and 531)
· Propagation prediction for line-of-sight systems
_______________________
