Equalizer architecture tradeoffs for magnetic recording channels

The bit error rate (BER) performance of various equalizer architectures consisting of a continuous time filter (CTF) and analog adaptive FIR filter are evaluated. Among the CTFs examined are the 4th and 6th order Butterworth, and 7th order equiripple linear phase filter. FIR filters of length 3 to 10 are considered. It is shown that, with adequate optimization of the CTF boost and bandwidth, the performance of the equalizers is relatively insensitive to the number of FIR taps or the CTF type. However it is also shown that choosing a very small number of FIR taps is impractical because the space of CTF boost and bandwidth settings yielding close to optimum performance becomes extremely small.