u/Pheonixrulr

Hello,
My university team (me and friends from B.tech EEE dept) are finalizing a funded pitch to build a permanent ground station in Chennai, India. The objective is to capture and decode live C-band weather imagery and telemetry directly from INSAT-3DS (~4.7 GHz).

Before we send the BoM for funding pitch, our mentor recommended posting a sanity check on different forums and subreddits.

We are in SRMIST KTR (main campus), chennai trying for INSAT-3DS

The Architecture:
(since the satellite dish will be at the roof pointing at the sattelite, and the project lab is 2 floors down)

• Antenna: 1.8m Prime Focus Mesh Dish on a non-penetrating roof mount with concrete ballast.
• RF Front End: C-Band feedhorn with a scalar ring feeding into a standard C-Band LNA.
• Digitization (On-Roof): Airspy R2 or HackRF One connected to an Intel NUC (or Raspberry Pi 5).
• Enclosure: All electronics housed in a waterproof enclosure, mounted behind the dish for shade. We are thinking of using waterproof nylon cable glands.
• Data Transport: Cat6 Ethernet running two floors down to the lab.
• Software Pipeline: SatDump running in server mode on the roof PC, streaming the 10 MSPS IQ data to the lab PC for QPSK demodulation and decoding.
• The specs of the PC getting the data is not finalized yet but we were considering atleast intel i5(or higher), 12gb ddr4 RAM (or higher and cheaper) and 512 gb storage hdd (or more)

Link Budget Estimate:

• Target Satellite: INSAT-3DS (74°E)
• Distance: ~36,000 km
• Frequency: ~4.7 GHz
• Estimated Link Margin: ~10 dB (assuming a 1.8m mesh dish at ~55% efficiency).

Where we need your critique:

1. C-Band Interference: Chennai is a major coastal city with local radar and heavy 5G deployment. Will a standard C-band LNA get saturated, and should we budget for a dedicated cavity bandpass filter before the LNA?
2. Thermals: Chennai ambient temperatures hit 40°C (104°F). Even in the shade of the dish, will an Intel NUC or Pi 5 thermal-throttle while processing a continuous 10 MSPS QPSK stream inside a sealed box with only a breather vent?
3. Mechanical Alignment: Any practical tips for perfectly centering a feedhorn on a multi-petal mesh dish without access to professional laser alignment tools?

We appreciate any blunt feedback or teardowns of this plan before we spend institutional money. Thanks.