## Lecture 6

- Phase
- 270 degrees = 3/2 pi
- 360 degrees = 2 pi
- 180 degrees = pi
- 90 degrees = ½ pi

- 270 degrees = 3/2 pi
- Wavelength
- Pi = vt
- pi(
*f*) = v

- Pi = vt
- periodic signals
- with fundamental frequency of
*f*_{0}= 1/t Hz may be represented by the 'fourier series', defined as:

- with fundamental frequency of
- Sampling
- Obtain the value of signal every T seconds
- Choice of T is determined b how fast a signal changes, it, the frequency of content of the signal
- Nyquist sampling theorem says:
- Sampling rate (1/T) >= maximum frequency in the signal

- Sampling rate (1/T) >= maximum frequency in the signal
- An analogue signal
- Defined for all time can have any amplitude

- Defined for all time can have any amplitude
- Discrete time signal:
- Defined for multiples of T can have any amplitude
- Must be sure sampling rate is greater than maximum frequency of the signals

- Defined for multiples of T can have any amplitude

- Choice of T is determined b how fast a signal changes, it, the frequency of content of the signal
- Quantization
- Approximate signal to certain levels. Number of levels used to determine the resolution
- Digital signal
- Defined for multiples of T amplitude limited to a few levels

- Defined for multiples of T amplitude limited to a few levels

- Approximate signal to certain levels. Number of levels used to determine the resolution

## No comments:

Post a Comment