English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

This paper presents an analysis work for suitable signal modulation schemes on Narrowband 3 kHz HF channels. The most efficient power for each constellation size in QAM and PSK schemes are calculated in the 3 kHz channel. In addition to simulation proofs, the results were proven in real experiments. In a simulated work, the data were tested through two channel types; AWGN and Waterson channel. While in real scenario data are transmitted from Tehran to Semnan city. For both the simulated and real scenarios, two modulation schemes, QAM and PSK, were tested. It was proved that 32 QAM has the best performance over Narrow Band 3 kHz HF channels. The results are considered a good reference for later enhancement of non-contiguous techniques or 3 kHz single tone in order to enhance the bit rate for any HF link.

QAM and PSK modulation performance analysis over narrow band HF channel