7 November 2017

SkyOFDM 28-tone, 65.6Bd BPSK, 2.6KHz bandwidth

These transmissions have been spotted during the last weekend on 4155.0 KHz/USB by ANgazu using a remote KiwiSDR located in Norway.
The waveform has a bandwidth of 2600 Hz and uses OFDM technology for 28 channels, each with BPSK modulation at rate of 65.6 symbols/sec. Speed and modulation are confirmed by analyzing the whole signal and also a single channel.
Almost certainly it is a Skysweep Technologies proprietary waveform, probably test transmissions. The user is unknown.

Fig. 1 - analysis of the whole signal
Fig. 2 - analysis of the upper channel