Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. Explain Multiplexing Systems?
A multiplexing system is one in which two or more signals are transmitted jointly over the same transmission channel. There are two commonly used methods for signal multiplexing. In frequency-division multiplexing (FDM), various signals are translated to nonoverlapping frequency bands. The signals are demultiplexed for individual recovery by bandpass filtering at the destination. FDM may be used with either analog or discrete signal transmission. Time - division multiplexing (TDM), on the other hand, makes use of the fact that a sampled signal is off most of the time and the intervals between samples are available for the insertion of samples from other signals. TDM is usually employed in the transmission of discrete information. Let us now describe basic FDM and TDM systems.
Figure (a) shows a simple FDM system which is used in telephone communication systems. Each input is passed through a low-pass filter (LPF) so that all frequency components above 3 kHz are eliminated. It is then modulated onto individual subcarriers with 4-kHz spacing. While all subcarriers are synthesized from a master oscillator, the modulation is achieved with single sideband (SSB). The multiplexed signal, with a typical spectrum as shown in Figure (b), is formed by summing the SSB signals and a 60-kHz pilot carrier. The bandpass filters (BPFs) at the destination separate each SSB signal for product demodulation. Synchronization is achieved by obtaining the local oscillator waveforms from the pilot carrier. Telephone signals are often multiplexed in this fashion.
A basic TDM system is illustrated in Figure (a). Let us assume for simplicity that all three input signals have equal bandwidths W. A commutator or an electronic switch subsequently obtains a sample from each input every Ts seconds, thereby producing a multiplexed waveform with interleaved samples, as shown in Figure (b). Another synchronized commutator at the destination isolates and distributes the samples to a bank of low-pass filters (LPFs) for individual signal reconstruction.More sophisticated TDM systems are available inwhich the sampled values are converted to pulse modulation prior to multiplexing and carrier modulation is included after multiplexing. Integrated switching circuits have made the TDM implementation much simpler than FDM.
Q. what is frequency synthesized signal generator? Describe its circuit in detail. OR Give the circuit details of frequency synthesizer also explain its working. OR
The Octal Inverter 74LS 240 It is similar to above octal buffer but with inverter output. The logic diagram is shown in figure below . Normal 0
Define Gain and Phase Responses? Expressing H(e j? ) in polar form as: H (e j? ) = G (?) e jφ(?) G(?) is the "gain" of the discrete-time system and φ(?) is the "phas
disadvantages of shunt&series clippers
Q. Explain the frequency response curve of a RC coupled amplifier The frequency response curve of a typical RC coupled Amplifier is shown below: In mid frequency range
Q. With a cross sectional view, explain the working of a depletion type MOSFET Draw a biasing amplifier circuit DEPLETION-TYPE MOSFET: Two types of FETs: JFETs and MOSFETs. MOS
Q. Differential amplifier to eliminate the common-mode voltage? The transducer in some cases may have a local ground that cannot be disconnected. In such a case, a separate gro
Q. The loop gain of an elementary feedback control system(see Figure) is given by G(s)·H(s), which is 10/(1+s/2)(1+s/6)(1+s/50). Sketch the asymptotic Bode plot of the loop-gain fu
Earth Leakage : Earth leakage takes place when, through some fault in an appliance or its connections. Electric current escapes to earth i.e. the body of the appliance become 'liv
Q. Determine the open-circuit output voltage v o of the system shown in Figure as a function of the input voltage v i .
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd