On the Capacity of Mid-latitude High Frequency Ionospheric Channel
Résumé
In this paper we consider the theoretical characterization of the ionospherictransmission. More accurately, we derive a closed form expression of the average capacityfor Mid-latitude High Frequency (HF) ionospheric channels. Heretofore, this problem hasbeen studied for Rayleigh channels when each tap of the impulse response has a Rayleighdistribution without characterizing the variance of this distribution. In this paper, we extendthese works to HF ionospheric channels by evaluating the variance of the amplitude attenuationversus the Doppler spread and then the channel capacity. For a multipath HF ionosphericchannel, we model the Doppler phenomenon as a Gaussian profile which is suggested for HFenvironments. Finally, we derive a closed form expression of the average channel capacityusing the probability density function (pdf) of the instantaneous impulse response. Numericalresults on both simulated and real measured data are derived at the end of the paper.