Advantages and disadvantages of FIR and IIR filters

FIR stands for finite impulse response. Most of the FIR full form filter is that linear phase filter When the linear phase filter is desired an FIR filter is usually used. Here this article gives information about the advantages and disadvantages of FIR as well as IIR filters to know more details about it. 

Advantages of  FIR filters :
  • FIR filter is always stable
  • It is simple
  • Design complexity generally linear
  • FIR filter are having linear phase response
  • It is easy to optimize
  • Non causal
  • Transient have a finite duration
  • Quantization noise is not much as a problem
  • Round of noise error is minimum
  • Both filtering recursive, as well as nonrecursive filter, can be also designed using FIR designing techniques
  • For designing of a filter having an arbitrary magnitude response; FIR filter designing techniques can be easily applied
  • Good performance
  • Robust
  • The necessity of computational techniques for filter implementation
  • A requirement of large storage
  • Incapability of linear phase response
Disadvantages of FIR filters :
  • Large storage requirements
  • Can not simulate prototype analog filter
  • For the implementation of FIR filter complex computational techniques are required to implement
  • It is hard to implementation than IIR
  • Expensive due to a large order
  • Require more memory
  • Time-consuming process
IIR stands for infinite impulse response. IIR Filter has a lower filter order then a corresponding FIR filter. Here this article also gives information about the advantages and disadvantages of  IIR filters to know more details about it.

Advantages of IIR filters :
  • It has a stable design
  • An IIR filter has a lesser number of side lobes in the stop band then FIR filter with the same number of parameters
  • Implementation of an IIR filter involves fewer parameters 
  • Less memory requirement
  • Lower computational complexity
  • Analog frequency and digital frequency are linearly related
Disadvantages of IIR filters :
  • This filter is useful only when the analog filter is bandlimited
  • They are harder to implement using fixed-point arithmetic, such as noise generated by calculations and also a limit cycles
  • They are more susceptible to the problem of line finite length arithmetic
  • They don't offer the computational advantages of FIR filter for the multi-rate application system
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