I have written software to detect the transmission of frequency sequences.
I'm using Geortzel's Algorithm to filter desired frequencies from a data array. The data array is generated from audio capture. I am transmitting a sequence of bits encoded in two frequencies,
Currently, my signal-to-noise ratio is not satisfactory and even with scaling and thresholding of the signals, I am getting too many false positives.
I've had the idea to use two independent frequencies to represent each the mark and the space (4 frequencies in total) and only register a valid signal if both are detected simultaneously. This seems like it would only approximately double the computation time which is acceptable.
Would this improve improve the accuracy of my detection, or would it have no effect on my signal-to-noise ratio? Would it also increase the likelihood of false negatives and missed detections?