Analog-To-Digital convertor Sampler Quantization Coding.

Sampling of analog signal This is the conversion of a continuous-time signal into discrete-time signal obtained by taking samples of the continuous-time signal at discrete-time instant

Quantization of Continues –Amplitude Signals Quantizer convert the continouse amplitude into finite sets of discrete value called quantization level There is an error due to this conversation called quantization error … The distance between the two levels is Δ and its computed as

Example (1-3):- Consider the analog signal x(t) is an input to analog to digital convertor,what is the output of sampler and quantizer if the sampling rate is 1Hz. Let the number of quantization level =11 Where, take only 9 samples.

Coding of Quantized Samples With a word length of b bit we can create different binary numbers

Digital-To-Analog converters

Discrete time signals

representation of the discrete time signal 3. Sequence representation An infinite-duration signal or sequence with the time origin (n=0) indicated by the symbol ↑ is represented as

Some elementary discrete time signals

b. Amplitude modification of discrete time signal Amplitude scaling The sum of two signals The product of two signals

H.w : For the signal shown below,sketch the following signals X(n-2) X(n+3).δ(n-2) X(n-1)+u(-n+1)

Classification of discrete time signal Even and Odd signals:- A real-valued signal is said to be even if for all n x(n) = x(-n) Whereas a signal is said to be odd if for all n x(n) = -x(-n) X(n)=xe(n)+xo(n) To find the even part of x(n) Whereas to find the odd part of x(n)

Example 2.3: - Find the even and odd parts of the following signal: Periodic and Aperiodic Sequences A signal x(n) is said to be periodic if and only if x(n)=x(n+N) for all n. Example 2.4: Determine if the following signal is periodic or not then find its period