Dig Out Your Brick Phone! Bringing AMPS Back with GNU Radio presented at ShmooCon 2017

by Brandon Creighton,

Summary : AMPS, the first widely deployed cellular network in the US, was old enough that it had been designed by pre-breakup Bell, yet robust enough to survive for decades in service. Unlike LTE or even GSM, it was also a protocol simple enough to be described in a fairly short specification; if you wanted to you could listen to calls with a TV tuner (or modified phone).
This is a talk on the design and implementation of gr-amps, a set of GNU Radio blocks that can turn a TX-capable software-defined radio into a base station for AMPS devices–including that brick phone in your basement. No background in SDR is necessary to follow along (but it doesn’t hurt).
Expect detours into near-forgotten phreaker history: the weaknesses that enabled phone cloning, the efforts of wireless carriers and the US government to fight exploitation, and more.