Decode the coded data by using the Viterbi algorithm with the specified trellis structure, 34 for its traceback depth, truncated operation mode, and hard decisions. Convolutionally encode the data, by using the specified trellis structure. It is normally syncronous with clock extraction (Note clock extraction requires some digital encoding on the tx end.) Normally it involves 2 frequencies one of which would represent a 0 and the other a 1. FSK is Frequency shift keying and is an old technique for sending digital info on an analog channel.WinAFSK Homepage WinAFSK is a program that allows you to view packet radio traffic, with your radio's audio output connected to your sound device's microphone connector, or with a SDR device or also WebSDR, using an application such as Virtual Audio Cable.In addition, a package called Signal Analyzer has the ability to analyze digital signals with great complexity and variety. WinRadio's Universal FSK decoder Spectrum analyzer, character analysis, can estimate baud rates (with some modes) and a bit inversion parser.Some HID readers can output RS-232 serial data instead of Weigand. My Arduino Wiegand decoder demonstrates this for both the 26 bit and 35 bit formats. To decode the bit sequences from HID RFID readers using Wiegand, I usually connect the readers to a microcontroller and implement the decoding there.
