On 4/20/22 03:06, Mark Jessop wrote:
I have to question the use of LoRa on amateur satellite bands. LoRa is a closed, patented, proprietary mode. SDR implementations of it (if they work...) are legally dubious, leaving us to have to use Semtech hardware to receive. Why are we allowing this? I thought amateur radio was meant to be open and free for all to experiment, modify, and learn?
Hello Mark,
I share your concerns with the use of LoRa for Part 97 operations. As you have mentioned, it is closed, patented, and proprietary, and has no place in our service. I feel similarly about AMBE, the voice codec used in many of the digital voice modes.
LoRa's claim to fame is resistance to interference, being a frequency-chirped spread-spectrum mode. There is no technical reason that another device or purpose-built hardware could not achieve the same sensitivity on a coordinated frequency for a given bandwidth and data rate.
Nick is correct: Individual support from large silicon vendors will be lacking until we're buying 100k+ units per year.
We need amateurs interested in using commodity hardware (ON AX5043, ADI ADF7021, etc) to step forward and start experimenting. This "new frontier" requires the combined efforts of both those experienced in RF and those comfortable in the digital/programming world to step forward and cooperate.
If this sounds like something anyone is interested in, please contact me and/or visit https://www.amsat.org/volunteer-for-amsat/
--- Zach N0ZGO