Raspberry Pi for Home build frequency spectrum analyzer
I would like to use my Raspberry Pi to build a frequency spectrum analyzer (for the 5Ghz band) but looking at the high costs for commercial models I feel that I am missing something. So instead of just going ahead, and probably wasting a lot of time and some money, I would like to ask for some expert advice or warning. Here are my thoughts so far:
Possible solution 1: Use a 5 GHz Wifi USB adaptor to receive Radio signals (The adaptor should be able to receive a bandwidth of 40Mhz somewhere around the 5 MHz wifi frequency). I am not sure how to “tell” the wifi adaptor to provide the raw signal in digital form so that I could use the Raspberry to do a Fast Fourier Transformation on it.
Possible solution 2: Build an antenna suited to the 5GHz frequency (My understanding is that this antenna will pick up a whole bunch of frequencies with different amplitudes). Not sure if a filter would be required to clean the signal. In the next step I would connect the antenna to an Analog/Digital converter and in this way send the digital signal to the Raspberry Pi. There I would do a Fast Fourier Transformation to identify the relevant sinuous frequencies that make up the overall received signal.
Any thoughts would be really welcome. As I stated before I feel that I am missing something, probably due to my lack of profound (especially practical) knowledge of radio technology.
Jens
I would like to use my Raspberry Pi to build a frequency spectrum analyzer (for the 5Ghz band) but looking at the high costs for commercial models I feel that I am missing something. So instead of just going ahead, and probably wasting a lot of time and some money, I would like to ask for some expert advice or warning. Here are my thoughts so far:
Possible solution 1: Use a 5 GHz Wifi USB adaptor to receive Radio signals (The adaptor should be able to receive a bandwidth of 40Mhz somewhere around the 5 MHz wifi frequency). I am not sure how to “tell” the wifi adaptor to provide the raw signal in digital form so that I could use the Raspberry to do a Fast Fourier Transformation on it.
Possible solution 2: Build an antenna suited to the 5GHz frequency (My understanding is that this antenna will pick up a whole bunch of frequencies with different amplitudes). Not sure if a filter would be required to clean the signal. In the next step I would connect the antenna to an Analog/Digital converter and in this way send the digital signal to the Raspberry Pi. There I would do a Fast Fourier Transformation to identify the relevant sinuous frequencies that make up the overall received signal.
Any thoughts would be really welcome. As I stated before I feel that I am missing something, probably due to my lack of profound (especially practical) knowledge of radio technology.
Jens