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First Fully Digital Radio Transmitter Built Purely From Microprocessor Tech
Zothecula writes For the first time in history, a prototype radio has been created that is claimed to be completely digital, generating high-frequency radio waves purely through the use of integrated circuits and a set of patented algorithms without using conventional analog radio circuits in any way whatsoever. This breakthrough technology promises to vastly improve the wireless communications capabilities of everything from 5G mobile technology to the multitude devices aimed at supporting the Internet of Things (IoT).
No actual info in article, just hype and buzzwords.
Strange things are afoot at the Circle-K.
Must be a slow news day. You can't patent algorithms
Harrison's Postulate - "For every action there is an equal and opposite criticism"
No problem generating RF with digital circuits; it has been done for decades. The trick is to generate clean frequencies with no significant harmonic content and no spurs. Now perhaps the cicuits used in this article are digital and analog on one silicon substrate. Certainly a DAC can be made using a semiconductor resistor network fabbed on the same substrate as the digital electronics. And capacitors and inductors can be fabbed on a silicon substrate. I would like to see the details of what they are actually doing. "Pure digital" sounds like a phony to me.
OK, no real technical data and some absurd claims here.
First all-digital transceiver? No. There have been others. Especially if you allow them to have a DAC and an ADC and no other components in the analog domain, but even without that, there are lots of IoT-class radios with direct-to-digital detectors and digital outputs directly to the antenna. You might have one in your car remote (mine is two-way).
And they have to use patented algorithms? Everybody else can get along with well-known technology old enough that any applicable patents are long expired.
It would be nicer if there was some information about what they are actually doing. If they really have patented it, there's no reason to hold back.
Bruce Perens.
People have done this on TI calculators (& likely other systems with similarly little shielding & sufficient clock rates). No hardware support needed—just cause some long enough trace (e.g. on the data bus) to oscillate at the correct frequency. Granted, a 6 MHz Z80 can pretty much only only do AM radio (& can only be picked up right next to the radio), but the principle is not new.
I could build a "Fully Digital Radio Transmitter" in a few minutes using a Crystal and a CMOS gate.
The 1620 was an all digital machine built of discrete transistors. As an undergraduate, we wrote programs that caused the machine to alternate between two loops at a variable rate. The computer radiated so many harmonics that this could be heard all across the AM band where no strong station existed. We programmed it to play (mostly) classical music, "Flight of the Bumblebee" was the perennial favorite. Any truly all digital transmitter will generate harmonics outside of the allowable FCC band, so at the very least they need a really good analog bandpass filter on the output.
Uh, The spark gap transmitters used by Hertz and Marconi were digital (Morse code is a digital protocol) and for the most part the only tuning was done by the antenna. Latter there was some sort of tank circuit or resonant tuning added, but I don't think so in the beginning.
I already listen to music from my Raspberry Pi using it as a transmitter with no analogue components - http://naich.net/wordpress/?p=...