Statistical Modeling of Low-Latitude Long-Distance Hf Ionospheric Multi-Mode Channels

Abstract

Studies have been reported in the literature on High Frequency (HF) radio channels in mid-latitude areas more frequently than in low latitudes, where the ionospheric channels might behave differently. This paper reports a statistical model of HF sky wave channel complex impulse response and its parameters, i.e., channel gain, path gain, phase shift, and delay spread statistics, derived from both simulation and measurement on a 3044 km link in Indonesia. Evaluations show that multipaths observed with respect to their propagation delays form multiple clusters corresponding to different propagation modes. The channel gain is found to be Rayleigh distributed, whereas the rms and maximum delay spread exhibit Rayleigh and Gaussian distributions, respectively. This model can be used in performance evaluation of digital communication schemes in low-latitude HF channels.

Ionospheric Channel Impulse Response Measurement System for NVIS Propagation Mode Over Java Island Based on Low‐Cost SDR Platform

“…In the equatorial region, especially over Indonesia, there are only a few measurements of ionospheric channel characteristics, namely those carried out by Kurniawati et al (2018) and Harris and Scholz (2006). Kurniawati et al (2018) conducted an ionospheric CIR measurement with a 3,840 km circuit distance for 2 weeks in 2018.…”

“…In the equatorial region, especially over Indonesia, there are only a few measurements of ionospheric channel characteristics, namely those carried out by Kurniawati et al (2018) and Harris and Scholz (2006). Kurniawati et al (2018) conducted an ionospheric CIR measurement with a 3,840 km circuit distance for 2 weeks in 2018. They reported the distribution of Delay spread with mean values in the range of 0-100, 100-500, and 500-1,300 ms for three cluster multi-hop modes, namely 2F, 3F, and 4F.…”

“…From the configuration of the site's location, the system could measure the ionospheric CIR from single-hop and double-hop ionospheric "reflection" points. The ionospheric channel characteristics measured by Kurniawati et al (2018) and Harris and Scholz (2006) represent various combinations of skywave propagation modes based on their site's distance. Those long-range propagation modes differ from the near vertical incidence skywave (NVIS) propagation, where the distances are less than 200 km.…”

“…Kurniawati et al. (2018) conducted an ionospheric CIR measurement with a 3,840 km circuit distance for 2 weeks in 2018. They reported the distribution of Delay spread with mean values in the range of 0–100, 100–500, and 500–1,300 ms for three cluster multi‐hop modes, namely 2F, 3F, and 4F.…”

Design of Sliding Correlator Channel Sounder for Ionospheric Channel Probing Based on Software Define Radio

“…The channel sounder on the SDR platform has been implemented (Kurniawati, Hendrantoro, & Taufik, 2018;Mukti et al, 2014;Samayoa, Kock, Blume, & Ostermann, 2018). However, there are rooms to be investigated further on the technical design and the system performance based on ITU recommendation for ionospheric channel estimation, especially when dealing with the hardware limitations on available SDR.…”