Contents
What is Delta Modulation in ADC?
A delta modulation (DM or Δ-modulation) is an analog-to-digital and digital-to-analog signal conversion technique used for transmission of voice information where quality is not of primary importance. In delta modulation, the transmitted data are reduced to a 1-bit data stream.
What is Sigma-Delta type ADC?
Delta-sigma (ΔΣ; or sigma-delta, ΣΔ) modulation is a method for encoding analog signals into digital signals as found in an analog-to-digital converter (ADC).
What are the disadvantages of delta modulation?
Disadvantages of delta modulation:
- Slope overload distortion.
- Granular or idle noise.
- High bit rate.
- Its practical usage is limited.
- Poor start-up response.
- It requires a predicator and hence it is very complex.
- Modulator overload when slope of the signal is too high.
What kind of demodulator is used in delta modulation techniques?
Explanation: The demodulator used in delta modulation is a simple form of integrator. Explanation: Sources of noise in delta modulation are granularity and slope overload.
How is decimation used in the delta-sigma ADC?
Decimation is the process of discarding the unnecessary samples and is used as a mechanism to reduce the data rate to a usable value whilst maintaining the information according to the Nyquist Criterion. The Delta-Sigma ADC has two sampling rates, the input sampling rate (Fs) and the output data rate (Fd).
What is the ratio of FS to FD in Delta Sigma?
The ratio of Fs to Fd is known as the Decimation Ratio (DR). By reducing the filter’s passband and increasing the DR, whilst maintaining the same Fs, the effective number of bits (ENOB) for a Delta-Sigma ADC can be increased. Likewise, the bandwidth of the ADC can be increased at the expense of ENOB.
How is the delta sigma ADC different from the Nyquist rate ADC?
The Delta-Sigma ADC works a little differently from the Nyquist-rate ADC. It relies upon oversampling and noise shaping to achieve high-resolution conversions.
What is the theory behind a delta delta ADC?
Abstract: This in-depth article covers the theory behind a Delta-Sigma analog-to-digital converter (ADC). It specifically focuses on the difficult to understand key digital concepts of over-sampling, noise shaping, and decimation filtering.