Cascaded second-order sections

1. What is the advantage of implementing an IIR filter as a cascade of 2nd order sections?
2. What is a SOS filter?
3. What is second-order IIR filter?
4. What is an SOS Matrix?

What is the advantage of implementing an IIR filter as a cascade of 2nd order sections?

IIR Cascaded Second-Order Sections Form I

Comparing with the IIR Direct Form structures, the IIR Cascaded Second-Order Sections Form structures have more computational complexity. However, the cascaded structures help alleviate finite word length effects.

What is a SOS filter?

The SOS-filter is a simple sequence of two shaped pulses designed to populate and to store singlet spin order in coupled spin systems. The SOS-filter can be introduced as a block of an arbitrary NMR pulse sequence when one needs to detect only the spins that have passed through a long-lived singlet state.

What is second-order IIR filter?

2nd order IIR filter sometimes referred to as a 'bi-quad'. Internally, it has a fully pipelined architecture permitting the highest possible sample rates for IIR filtering. The SOS block is modular allowing any number of SOS blocks to be joined in series to implement higher order IIR filters. Key Design Features.

What is an SOS Matrix?

sos is an L-by-6 matrix that contains the coefficients of each second-order section stored in its rows. Row vectors b and a contain the numerator and denominator coefficients of H(z) stored in descending powers of z.