Intermodulation distortion in analog magnetic recording

Intermodulation distortion in analog magnetic recording is analyzed. Analyses are carried out both for two-signal superimposed recording in audiotape recorders and for color and video signal superimposed recording in video recorders. An error function is used to simulate tape magnetization characteristics assuming a Gaussian switching field distribution. Intermodulation distortion in video color signal recording is analyzed by using an M-H loop trace method taking into account recording demagnetization and by dividing the tape layer into thin layers. Computed results show good agreement with measured data, even with this simple model, without using iterative demagnetizing computation.