What is oversampling of ADC?
Oversampling is a popular method to improve ADC resolution. The input is sampled at a rate higher than the minimum required Nyquist sampling rate, fs.
Does oversampling improve resolution error?
Oversampling is capable of improving resolution and signal-to-noise ratio, and can be helpful in avoiding aliasing and phase distortion by relaxing anti-aliasing filter performance requirements. A signal is said to be oversampled by a factor of N if it is sampled at N times the Nyquist rate.
How do I get a higher resolution ADC?
The accuracy of a low-resolution ADC can be improved by oversampling the input signal using the ADC and subjecting it to low-pass filtering, using a FIR filter to filter out the quantization noise, and then decimating it.
What is an oversampling ratio?
Oversampling Rate – this is a resampling rate based on the original sampling rate. For example, if the original sample rate is 48 kHz, an oversampling rate of 2x infers a resampling or upsampling rate of 96 kHz. Upsampling – the process of resampling a signal at a higher rate than the incoming signal.
How does oversampling improve ADC resolution?
Oversampling Description As a general guideline, oversampling the ADC by a factor of four provides one additional bit of resolution, or a 6 dB increase in dynamic range. Increasing the oversampling ratio (OSR) results in overall reduced noise and the DR improvement due to oversampling is ΔDR = 10log10 (OSR) in dB.
What is decimation in ADC?
• Decimation decreases the sample rate of a signal by. removing samples from the data stream. • Decimation includes digital low pass (anti-aliasing) filter. followed by a decimator.
Does oversampling cause aliasing?
Oversampling reduces or completely gets rid of 3 forms of potential distortion a signal can have: aliasing, clipping, and quantization distortion.
How is ADC resolution calculated?
It is expressed as the number of bits output by the ADC. Therefore, an ADC which converts the analog signal to a 12-bit digital value has a resolution of 12 bits. -1. With a 3.3 V reference voltage, the resolution is 3.3/212 = 3.3/4096 = 0.805 (mV).
How can I increase my ADC SNR?
For the case of oversampling, where the signal bandwidth is less than the Nyquist bandwidth, the theoretical SNR of the ADC is increased by 3 dB each time the fs is doubled.
What is Delta Sigma 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).
How is ADC sound calculated?
Calculate 10 × log (fSAMPLE/2) = 10 × log (65Msps/2) = 75.1dB. The converter’s normalized Nyquist band noise power is found by subtracting 75.1dB from -66dBm resulting in -141.1dBm in a 1Hz bandwidth. The resulting effective ADC noise figure = -141.1dBm – KTB = -141.1dBm – (-174dBm) = 32.9dB.