This project turns a Gemtek W1700 K Wi-Fi 7 router into a wideband software-defined radio receiver. Its MediaTek MT7996 radio captures raw 14-bit IQ samples at up to 320 Msps, the Airoha AN7581 SoC streams them over 10 Gb Ethernet, and a Linux host displays live spectrum and waterfall views in the browser alongside the receiver's controls.
The system can observe the entire 2.4 GHz band at 320 Msps in real time, with an optional "flatten" correction that compensates for decimation roll-off. A 262,144-point FFT runs on every sample at 100 spectra per second. Sample rates of 40, 80, 160 or 320 Msps are supported on every band, and the local oscillator can be tuned across the 2.4, 5 and 6 GHz bands, retuning mid-stream in about 1 ms.
The MT7996 runs only custom firmware: a ROM patch, WM and WA built from the project repository, with no MediaTek code. It initializes the radio from a cold power-on, based on register-level analysis of MediaTek's own initialization and calibration, and accepts commands for LO, sample rate, capture, gain and filter from the host. To fit the 10 Gb link, half of the slices at 320 Msps are packed to 28 bits per sample pair on the radio's own cores, a process that is lossless and automatic.
Installation requires a W1700 K, a 3.3 V USB serial adapter, an Ethernet cable and a 10 Gb Ethernet NIC on the host. Running make builds everything from public sources, and the included test suites can be run with make check.
Source: Hacker News · Summarized by HeadlinesBriefing