Upload
rudra-kumar-mishra
View
212
Download
0
Tags:
Embed Size (px)
DESCRIPTION
bb
Citation preview
Chapter4Transmitters and ReceiversGeneralized TransmittersAM PM GenerationInphase and Quadrature GenerationSuperheterodyne ReceiverFrequency Division Multiplexing**
RUDRA KUMAR MISHRA
Generalized TransmittersAny type of modulated signal can be represented byThe complex envelope g(t) is a function of the modulating signal m(t)TransmitterModulating signalModulated signalExample:*Eeng 360 *
RUDRA KUMAR MISHRA
Generalized TransmittersR(t) and (t) are functions of the modulating signal m(t) as given in TABLE 4.1Two canonical forms for the generalized transmitter:Figure 427 Generalized transmitter using the AMPM generation technique.*Eeng 360 *
RUDRA KUMAR MISHRA
Generalized Transmittersx(t) and y(t) are functions of the modulating signal m(t) as given in TABLE 4.1Fig. 428 Generalized transmitter using the quadrature generation technique.*Eeng 360 *
RUDRA KUMAR MISHRA
IQ (In-phase and Quadrature-phase) Detector*Eeng 360 *
RUDRA KUMAR MISHRA
Generalized ReceiversReceiversTuned Radio Frequency (TRF) Receiver:Composed of RF amplifiers and detectors. No frequency conversionIt is not often used.Difficult to design tunable RF stages.Difficult to obtain high gain RF amplifiersSuperheterodyne Receiver:Downconvert RF signal to lower IF frequencyMain amplifixcation takes place at IF Two types of receivers:*Eeng 360 *
RUDRA KUMAR MISHRA
Tuned Radio Frequency (TRF) Receivers Composed of RF amplifiers and detectors. No frequency conversion. It is not often used. Difficult to design tunable RF stages. Difficult to obtain high gain RF amplifiers*Eeng 360 *
RUDRA KUMAR MISHRA
Heterodyning*Eeng 360 *
RUDRA KUMAR MISHRA
Superheterodyne ReceiversSuperheterodyne Receiver Diagram*Eeng 360 *
RUDRA KUMAR MISHRA
Superheterodyne Receiver *Eeng 360 *
RUDRA KUMAR MISHRA
Superheterodyne Receivers The RF and IF frequency responses H1(f) and H2(f) are important in providing the required reception characteristics.*Eeng 360 *
RUDRA KUMAR MISHRA
Superheterodyne Receivers*Eeng 360 *
RUDRA KUMAR MISHRA
Superheterodyne Receivers*Eeng 360 *
RUDRA KUMAR MISHRA
Superheterodyne Receiver Frequencies *Eeng 360 *
RUDRA KUMAR MISHRA
Superheterodyne Receiver Frequencies *Eeng 360 *
RUDRA KUMAR MISHRA
Frequency Conversion Process*Eeng 360 *
RUDRA KUMAR MISHRA
Image Frequencies Image frequency not a problem. Image frequency is also received*Eeng 360 *
RUDRA KUMAR MISHRA
AM Radio Receiver*Eeng 360 *
RUDRA KUMAR MISHRA
Superheterodyne Receiver Typical Signal Levels*Eeng 360 *
RUDRA KUMAR MISHRA
Double-conversion block diagram.*Eeng 360 *
RUDRA KUMAR MISHRA
**