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
*
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IQ (In-phase and Quadrature-phase) Detector*Eeng 360 *
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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 *
Superheterodyne Receivers The RF and IF frequency responses
H1(f) and H2(f) are important in providing the required reception
characteristics.*Eeng 360 *
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Superheterodyne Receivers*Eeng 360 *
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Superheterodyne Receivers*Eeng 360 *
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Superheterodyne Receiver Frequencies *Eeng 360 *
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Superheterodyne Receiver Frequencies *Eeng 360 *
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Frequency Conversion Process*Eeng 360 *
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Image Frequencies Image frequency not a problem. Image frequency
is also received*Eeng 360 *
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AM Radio Receiver*Eeng 360 *
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Superheterodyne Receiver Typical Signal Levels*Eeng 360 *
