Advice needed about rocket performances

[mheslep]

you would need 200,000 times this power

Dish size on Wu's spacecraft is also a factor in that multiple. Though as you point out, if the craft is powered by laser it can certainly communicate far more efficiently. Without googling, I wonder if NASA is considering such for future deep space spacecraft . Maybe the improvements in solid state laser power make this a possibility, or not.

 

[mfb]

The factor 200,000 times is for spacecraft -> inner solar system only (and you can reduce it with a larger dish for the spacecraft ). For the other direction, you probably want a smaller dish and a larger sender power - if you increase power by a factor of 1000, you can reduce the dish size by a factor of 1000, reducing the 70m dish to a 2m dish (ignoring issues with angular resolution here).
And this is for radio waves. I did not find numbers (apart from the data transmission rate) for NASA's test, but apparently it gives better data rates with lower power.