Radio Communication System – Block Diagram and types: Radio communication is very popular technique of communicating a message. The radio waves are electromagnetic waves produced due to escape of electrical energy into free space. They have a frequency range from a few hertz to gigahertz. They travel with a velocity of light i.e., 3 x …
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Foster Seeley Detector – Circuit Diagram, Working and its Phasor Diagram: The circuit diagram of the Foster Seeley detector is shown in Fig. 22.54. This Foster Seeley Detector circuit consists of an inductively coupled double tuned circuit in which both primary and secondary coils are tuned to the same frequency (intermediate frequency). The centre of …
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Balanced Slope Detector – Working, Advantages and Disadvantages: The circuit of a balanced slope detector is shown in Fig. 22.53 (a). This circuit employees two slope detectors connected back to back to the opposite ends of a centre tapped secondary of the transformer. Thus voltages supplied to the two sides are in phase opposition. The …
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Simple Slope Detector – Circuit diagram and its Characteristics: The circuit diagram of a simple slope detector is depicted in Fig. 22.52(a). This Slope Detector circuit consists of a tuned circuit which is slightly detuned from the carrier frequency ωc. In other words, the circuit uses two tuned circuits which are tuned to two different …
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Transistor Detector Circuit Working Principle: It is possible to achieve amplitude demodulation by using a three-element electronic device. A typical example of such a configuration is illustrated in Fig. 22.51. This circuit is called a transistor detector. In addition to detection of the modulated carrier input signal, it also furnishes amplification of the modulating signal. …
Linear Diode Detector or Envelope Detector: Diode detection is called the envelope detection as it recovers the audio frequency signal envelope from the composite signal. Diode detector is also called the linear detector as its output is proportional to the voltage of the input signal. Linear diode detector makes use of rectification property of a …
Square Law Detector Circuit and Working Principle: The square law detector circuit is used for demodulating modulated signal of small amplitude (i.e., below 1 V) so that the operating region may be restricted to the nonlinear portion of the V-I characteristics of the device. Figure 22.48 shows the circuit of a square law detector. It …
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Amplitude Detection Process: Amplitude Detection – The process of demodulation demands that the modulated wave has some definite average value and the carrier wave is separated out. Hence in demodulation of an AM wave two operations, viz. rectification of the modulated wave and elimination of the RF component of the modulated wave are involved. Essentials …
What is Demodulation or Detection? – Need of demodulation: Demodulation or detection is a process of recovering the original modulating signal (intelligence) from the modulated carrier wave i.e., the demodulation is a process reverse of the process of modulation. Need of demodulation: The wireless signals transmitted from a transmitter consist of RF carrier waves and …
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Single Sideband Modulation (SSB): Single Sideband Modulation (SSB) can he obtained by passing the output of a carrier suppressor (product modulator) through filter circuits that are selective to transmit one sideband while suppressing the other. However, this method is suitable only for obtaining Single Sideband Modulation corresponding to low or moderate carrier frequencies. The other …