written 7.8 years ago by | • modified 2.9 years ago |
Mumbai University > Electronics and Telecommunication Engineering > Sem 6 > Data Communication
Marks: 10 Marks
Year: Dec 2016
written 7.8 years ago by | • modified 2.9 years ago |
Mumbai University > Electronics and Telecommunication Engineering > Sem 6 > Data Communication
Marks: 10 Marks
Year: Dec 2016
written 7.8 years ago by |
Binary Frequency Shift Keying (BFSK)
Time domain representation:
The transmitted signal can be represented as:
$$s_i(t)=\bigg\{^{\sqrt{\dfrac{2T_b}{T_b}}\cos(2 \pi f_il), 0\lt1\le T_b} _{0,\hspace{2cm} elsewhere}$$
$$f_1=f_c+\dfrac{1}{2T_b} \ \ \ \ f_2=f_c-\dfrac{1}{2T_b}$$
The minimum frequency spacing between two adjacent frequency slots to ensure orthogonality for the continuous phase BFSK is
$\dfrac{1}{2T_b}$
Phase Discontinuous Frequency Shift Keying
Generation of BFSK
Coherent Detection of BFSK
Bandwidth of FSK:
The null to null bandwidth of FSK is
$B.W \gt 2R_b$
Power Spectral density of BFSK
We need two phasor
Two carrier are used .The frequency are selected in such a way that two carrier will be orthogonal to each other.
$∫_0^{Tb}\sqrt{2p} \cos(2πf_Ht) \sqrt{2p} \cos(2πf_Lt) = 0$