besself Bessel filter design. [b, a] = besself(n, Wc) [b, a] = besself (n, Wc, "high") [b, a] = besself (n, [Wl, Wh]) [b, a] = besself (n, [Wl, Wh], "stop") [z, p, g] = besself (…) […] = besself (…, "z") n: positive integer value (order of filter) W: positive real value 1).Analog 3dB cutoff frequency/frequencies for analog filter, in the range [0, Inf] {rad/sec} 2).Normalised digital 3dB cutoff frequency/frequencies for digital filter, in the range [0, 1] {dimensionless} This function generates a Bessel filter. The default is a Laplace space (s) or analog filter. If second argument is scalar the third parameter takes in high or low, the default value being low. The cutoff is Wc rad/sec. If second argument is vector of length 2 ie [Wl Wh] then third parameter may be pass or stop default is pass for bandpass and band reject filter respectively [z,p,g] = besself(...) returns filter as zero-pole-gain rather than coefficients of the numerator and denominator polynomials. [...] = besself(...,’z’) returns a discrete space (Z) filter. Wc must be less than 1 {dimensionless}.