The wigner distribution of sum-of-cissoids and sum-of-chirps processes for the modelling of stationary and non-stationary mobile channels Conference Paper uri icon

abstract

  • This paper concerns the time-frequency analysis of stationary and non-stationary multipath flat fading channels. For the modelling of stationary multipath fading channels, we use a sum-of-cisoids (SOCi) process, while the non-stationary channel is modelled by a sum-of-chirps (SOCh) process that captures the time-variant Doppler effect caused by speed variations of the mobile station. For the time-frequency analysis, we apply the concept of the Wigner distribution. Closed-form solutions are provided for the Wigner distribution of SOCi and SOCh processes. It is shown that the obtained Wigner distributions can be expressed by the sum of an auto-term representing the true Doppler power spectral density (PSD) and an interfering cross-term that does physically not exist. A simple method is proposed to eliminate the interfering cross-term. The proposed method allows tracing the instantaneous Doppler frequencies of multipath fading channels in non-stationary propagation environments, which is an important topic in mobile radio channel modelling. © 2016 IEEE.

publication date

  • 2016-01-01