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. Describe about Boltzmann constant? The constant η in Figure (b) stands for the noise power spectral density, expressed in terms of power per unit frequency (W/Hz). Statistic
Use PSpice to solve for the amplitude and phase of the current and the voltage across the inductor in the circuit shown in Figure(a).
can you let me know how much it would be for the answer to a question that has 2 parts
what is a button cells and how is it used on a low current electronic circuit
Determine the i-v characteristic of the network shown in Figure by the use of breakpoint analysis.
Why dummy coil is used in wave winding porpose of dc generator
Discuss the control words (ICWS) of IC8259. The Intel 8259 is a single chip programmable interrupt controller. It is compatible with 8086, 8088 and 8085 microprocessor. It is a
what is segmentation?
XTHL Exchange top of the stack with HL Instruction The contents of top two location of the stack are exchanged with the contents of HL register pair. The contents of reg
A DC shunt motor rotating at 1560 RPM is supplied from a 240-V source. The line current supplied to the motor is equal to 27 A. The shunt field resistance of the motor is equal to
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