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Hi, I'm John Gentile!

Welcome to my personal blog and technical notes! I'm passionate about solving interesting engineering problems. I like to be the "geek that can speak", so this site is mainly just for fun, but also acts as a continuous culmination of notes and thoughts that I'm learning (publicly) along the way. I'm a hacker (in the old-school, curiousity sense) and enjoy all things digital electronics, FPGAs, SDRs, DSP, embedded/low-level software, applied math and Machine Learning (ML), etc. See what I'm reading on goodreads.

LoRa Signal Decode

Once again, a neat challenge from DrSDR to decode a hidden string in a LoRa-like waveform. We are given some basic properties of the signal, namely the sampling frequency is 48kHz with 12khz bandwidth and spreading factor of 16. There are 4 chirps at start for sync, and each symbol is 4 bits, with 16 different symbols overall.

Posted by John Gentile on July 19, 2026

FPGA DSP Design & Verification with LLMs

Put simply, LLMs have gotten crazy good recently, going beyond typical software coding tasks, to even tackling HDL design. As those with experience in digital design know, this domain is not as simple to “code” as software: you’re really trying to coerce a chain of- often proprietary- EDA tools to map a desired function to a series of wires and hardware-specific primitives. Nonetheless, and even with much less open-source/high-quality training data, recent models have made leaps and bounds progress.

Posted by John Gentile on March 24, 2026

Unknown Chirp Message Decode

Another unknown signal challenge from DrSDR, the Chip-Text-Message- here a series of linear frequency modulated (LFM) chirps are representing bits, and we need to find the underlying text message in the waveform. An “upchirp” (where frequency is increasing as ejωte^{j \omega t}) represents a bit 1, where as an opposite “downchirp” (where frequency decreases as e−jωte^{-j \omega t}) represents a bit 0.

Posted by John Gentile on September 30, 2025

Unknown BPSK Decode

I saw an interesting DSP challenge come up in r/DSP, DrSDR/BPSK-Decode, in which a .wav file is given and we are looking to demodulate and decode the signal to get an “Amazon gift card claim code”.

Posted by John Gentile on September 29, 2025




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