←back to thread

Things you can do with a Software Defined Radio (2024)

(blinry.org)
940 points mihau | 4 comments | 16 Sep 25 14:35 UTC | HN request time: 0.105s | source
Show context
amelius ◴[16 Sep 25 15:25 UTC] No.45263574[source]▶
Is there SDR for the GHz range of signals used by modern equipment?
replies(4): >>45263614 #>>45263616 #>>45265098 #>>45266651 #
rlmineing_dead ◴[16 Sep 25 15:29 UTC] No.45263614[source]▶
You can get an AD9363 clone of the USRP b210 online for like, 300 USD?

The AD9363 stock is only supposed to be 325mhz to 3.8ghz but stuff like the plutoSDR which uses it manages to get the transceiver all the way from 70mhz to 6ghz like the more expensive AD9361 used in the real USRP B210s

Benefit is you can transmit stuff too, not just receive unlike the RTL-SDR which is RX only

replies(1): >>45263727 #
Bender ◴[16 Sep 25 15:38 UTC] No.45263727[source]▶
Is there anything like this that can go down to 15 MHz or lower? including transmit and several analog modes of modulation USB LSB NFM WFM AM CW at least
replies(2): >>45264024 #>>45268261 #
1. kavouras ◴[16 Sep 25 15:59 UTC] No.45264024{3}[source]▶
If I understand what you're saying, you can do any modulation scheme with sdr, it doesnt depend on the model
replies(1): >>45264082 #
2. Bender ◴[16 Sep 25 16:03 UTC] No.45264082[source]▶
Groovy. Are there any limiting factors such as processor speed and what is the best software that does it all on Linux? I have no idea what ratio of magic smoke is in the software vs. ratio of magic smoke is in the hardware.
replies(2): >>45266902 #>>45282878 #
3. pests ◴[16 Sep 25 19:37 UTC] No.45266902[source]▶
The output of a usb radio like this is a set of IQ values which is the raw data from the ADC. The amount of values (samples) you get is device dependent and also limited by your interface. The RTL SDR 4 over usb can do up to 2.4-3.5MHz. The ADC on that device is 8 bit so you will get two 8 bit, IQ numbers per sample.

You can tune into remote SDR’s people set up to work with this data without having your own device or download recordings others have made.

It is this raw sample data that you then demodulate according to whatever scheme required on the PC side.

A great resource I found was pysdr.org. I had absolutely no background in RF and very little python experience but that guide explains everything from the ground up from how the IQ samples are physically generated and read in an antenna, all the modulation schemes you mentioned, and how to code useful things with the various devices. No affiliation but a great resource.

4. esseph ◴[17 Sep 25 23:44 UTC] No.45282878[source]▶
There are levels to this that can get very expensive very fast depending on what your intent is, and how comfortable you are with programming various FPGAs.