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Sorry about the question above on dwell time – I had asked about this under a general section back in June 2017 and forgot about it (120 uS / tune dwell time, 20 uS settling time was the answer given then – I assume it’s still correct). I would still like to know what the noise floor would be at 30 kHz RBW with 1 THz / sec sweep speed. I know it will likely increase as you go up in frequency. Thanks again.
Justin – thanks for all of the answers. The SM200A is clearly of interest to me and probably a whole bunch of other folks in the RF community. You guys are doing a great job at SignalHound.
Is the smallest RBW using the onboard FPGA then 250 MHz / 16384 =~ 15.26 kHz? Also, can the FPGA be configured (via the SM200A API) to yield nice even bin sizes, like 25 kHz? That would yield about 800,000 bins / sweep or about 3.2 MB sweep (4 bytes/bin)? With 120 uS min dwell time, it appears you can do a sweep in 15.625 mS + tune time, at least on paper. Is 50 sweeps / sec doable then with 25 kHz RBW? (50 * 3.2 MB / sweep = 160 MB/sec)
Can you elaborate on the sample rate of the A/D using 40 MHz patches vs 160 MHz patches? Are the patches fixed across the whole spectrum for a given scan (i.e. using 40 MHz patches requires about 500 patches to cover 100 kHz to 20 GHz, whereas using 160 MHz patches requires 1/4 as many or 125)? Also, is the FFT processing for a scan still performed in the host computer or is it performed in the FPGA instead? If performed in the host, it would seem that the USB3 speed is the limiting factor on scan speed for small RBW (ie 1 kHz).
Sorry for the confusion – I forgot about the processing gain of the FFT (I can see how a fast 14-bit ADC + FFT gain could get you there). Still another question – is the 110 dB dynamic range spur-free dynamic range across the entire 20 GHz range? If so, what are the conditions for this measurement (RBW, input signal levels, etc)? Sorry for the questions – I wish I had been at IMS2017 and would have asked the questions in person! The SM200A performance certainly appears very astonishing given the price point of < $12k.
Forgive me if this isn’t the correct forum to ask this question – I didn’t see another forum that appeared more appropriate. I’m curious about the dynamic range spec of the SM200A. More specifically, how is dynamic range defined for the analyzer? For example, if when in full spectrum scan mode (20 GHz), if each tune is say 160 MHz wide (125 tunes / sweep), can the analyzer distinguish a -130 dBm signal from a -20 dBm signal within the same tune? I’m assuming a very small RBW has to be used to get the noise floor down, but if you can scan 20 GHz once / second with 1khz bins and get 110 dB of dynamic range within a tune, then I’m going to do everything I can to get my company to buy one! That would seem to imply some extremely high performance A/D device that I’m not aware of. Thanks ahead of time for answering.
The SM200A looks very good! When can I get one? Any pricing information (even if just an estimate)?
