I always wondered this myself. I had certain ideas like maybe 160 out of 255 characters in an Ethernet Packet or some other method of squeezing the data in. Turns out that my thoughts on that were not all that far-fetched…
Looking for a data pipeline that would fit these micro messages, Hillebrand came up with the idea to harness a secondary radio channel that already existed on mobile networks. This smaller data lane had been used only to alert a cell phone about reception strength and to supply it with bits of information regarding incoming calls. Voice communication itself had taken place via a separate signal.
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