Just a general question: In regards to the Deep Space Network antennas, how does power from the transmitter of the antenna relate to the frequency used? I believe the antennas use X band frequency for uplink and downlink to communicate with the Voyager spacecrafts, but is there a limit of the power needed to reach that frequency?
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$\begingroup$ Interesting question! One of them has 400 kW on S-band but this is a special case. $\endgroup$– uhohCommented Jun 1, 2019 at 6:54
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When looking for technical information about spacecraft communications and other tech stuff, think DESCANSO. What is that? I'm glad you asked! When was the idea behind the DESCANSO Book Series first conceived, by whom, and what is it's “mission”?
In Volume 13, Deep Space Communications, Jim Taylor, Editor in Table 2.2 on page 34, you can see that the transmit power available for both the 34 meter dishes (BWG = "beam waveguide antenna") and the 70 meter dishes and for both S-band and X-band are all 20 kW.
However, the EIRP (Effective Isotropic Radiated Power) is different in each case because the gain of the antenna varies with the ratio of the diameter to the wavelength squared. So 70 m will have about +6.3 dB over 34 meters, and X-band will have +10.6 dB over S-band.
The 400 kW for the 70 meter dish at Goldstone is an exception that is rarely if ever used Has DSS-43 ever been used in high power mode (>>20 kW) for an emergency situation and the Ka-band is not used for deep space, though it is used in some cases...
- What is the highest non-optical frequency used or tested for use in deep space communication?
- Will there be “Near Space” Ka-band allocations for TESS?
