Presumably those types of devices aren’t required to be particularly accurate in terms of frequency distribution, so could just focus on a single frequency or event just act as a noise source, rather than an instrument for transmitting information.
It is once you apply enough Carson's Rule to it. (At this level, the term CW is usually used in contrast to pulse modulation, rather than all forms of modulation in general as would be the understood usage at HF.)
That's the question, whether the ADS system has much modulation BW at all. HUSIR has 8 GHz, which is a fair bit. My guess is that the ADS uses its gyrotron(s) as single-stage oscillators, like the giant microwave oven it is, rather than as amplifiers for a carrier that's generated and modulated at a much lower level. Modulating a CW gyrotron oscillator directly would involve manipulating high magnetic or electric fields at unrealistic rates, and any useful degree of signal purity or short-term stability would likely be off the table entirely.
OTOH the .PDF talks about PRF and pulse width, and specifies a 40% duty cycle, so who knows. If it is indeed a pulsed system, I don't see how it differs from whatever ADS uses. The specs aren't particularly challenging.
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[ 3.9 ms ] story [ 31.7 ms ] threadThe truck-mounted ADS is gyrotron-based like HUSIR, but apparently they are working on more-portable GaN-based sources (https://jnlwp.defense.gov/About/Frequently-Asked-Questions/A...).
The novel requirement must be the need for wider modulation bandwidth, or something like that.
That's the question, whether the ADS system has much modulation BW at all. HUSIR has 8 GHz, which is a fair bit. My guess is that the ADS uses its gyrotron(s) as single-stage oscillators, like the giant microwave oven it is, rather than as amplifiers for a carrier that's generated and modulated at a much lower level. Modulating a CW gyrotron oscillator directly would involve manipulating high magnetic or electric fields at unrealistic rates, and any useful degree of signal purity or short-term stability would likely be off the table entirely.
OTOH the .PDF talks about PRF and pulse width, and specifies a 40% duty cycle, so who knows. If it is indeed a pulsed system, I don't see how it differs from whatever ADS uses. The specs aren't particularly challenging.