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This looks like a job for Elon Musk. An array of solar powered satellites (possibly above the orbital plane) could be in proximity of both planets to form a mesh relay. This would create a network allowing continuous communication through solar conjunctions or other line of sight barriers.

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In the far field, the size of a simply-shaped beam will increase proportional to distance: $$w \approx \text{factor} \ \times L$$ where $w$ is the width and $L$ is the distance. Let's see if we can find the factor that explains all that data. There are two common simple shapes we use for the initial beam. One is a circular disk of uniform brightness (like a ...

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Below the table is the note: Laser aperture size: 80mm, Ka-band antenna size: 300mm, X-band antenna size: 600mm. Assuming physical limits for lowest possible beam size. 90% of the problem is solved by looking at $d/\lambda$ which is the initial diameter of the beam expressed in wavelengths. From the following: Will there be "Near Space" Ka-band ...

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Partial answer: To some extent optical links can be almost completely immune to sunlight! Temporal The signals are modulated on a "carrier frequency" the baseline rate at which the laser is modulated. For TV and appliance remote controls using infrared LEDs the frequency is something like 38 kHz, but for a telemetry signal using a modulated ...

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What does total noise power (received plus system) mean? Noise that's received by the antenna (everything on-frequency that isn't your desired signal, from other transmitters to lightning storms to the Sun), plus noise generated inside the receiver itself (all amplifiers are imperfect and add some noise; all resistors generate thermal noise; other ...

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What does total noise power (received plus system) mean? Usually it means everything that is not the signal you want. Noise can come from interference from other radio transmitters, other electronics devices and thermal noise inside the receiver system itself. A satellite based system does have some potential advantages compared to ground towers: Reception ...

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What the heck is Δ𝑓? You guessed it correctly: it is the bandwidth occupied by the signal. It is determined by the system you are dealing with. Let's take LTE (the standard used by our smartphones -aka 4G) as example. The standard stipulates that your device must support several CHANNEL bandwidths: 1.4,3,5,10,15,20 MHz. To derive the respective occupied ...

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This is interesting! At first I thought that optical communication always wins because the $\lambda/d$ for a 30 cm diameter telescope at 850 nm is about 350,000 whereas for a 3 meter dish on a deep space spacecraft at 8 GHz or 32 GHz Ka band is only 80 or 320. That factor of 1000 in $\lambda/d$ is a factor of a million in signal strength at the other end, or ...

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