Comprehension
Directions: Read the passage and answer the following four questions.
A digital filter uses a digital processor to perform numerical calculations on sampled values of the signal. The processor may be general-purpose such as a PC or specialized DSP chip. The analog input signal must first be sampled and digitized using an ADC. The resulting binary numbers, representing successive sampled values of the signal, are transferred to the processor, which carries out numerical calculations on them. These calculations typically involve multiplying the input values by constants and adding the products together. The results of these calculations, which now represent sampled values of the filtered signal, are converted back to the single using a DAC
Read the following statements regarding digital filters:
(i) its operation is determined by a program stored in the processor’s memory.
(ii) It cannot handle low-frequency signals accurately.
(iii) It can only be changed by redesigning the circuitry.
(iv) It is extremely stable with respect to both time and temperature.
Which of the above statements are correct?
Choose the correct answer from the code given below:
1. (i) and (ii)
2. (ii) and (iii)
3. (iii) and (iv)
4. (i) and (iv)
