EME and Weak signal communication
IQ+XT Software Define Radio exciter
IQ+ XT (144Mhz RF Exciter)
Download preliminnary documentation here
Performance measure on the RC1 (proto Nr.6)
RF power output: +10dBm
Harmonic response: better than 75dBc up to 5th harmonic.
LO leackage: >=75dB
Image rejection: >=80dB
Side band noise: @20KHz = -130dBc/Hz
@50KHz = -133dBc/Hz
The IQ+XT reach -156dBc/Hz@50KHz
After test several options for a Local oscillator I was able to reach a side band noise of -156dBc/Hz@50KHz just using a better oscillator with much less phase noise.
I'm preparing a document about the experiment I did to probe where the limits are for the LTC5598 (the IQ modulator used on the IQ+XT) and the results are promising, stay tune.