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. How speech is transmitted in digital switching environment by using PCM/TDM?
Ans:
A digital carrier system is a communications system which uses digital pulses instead of analogue signals to encode information. Figureshows the block diagram for a digital carrier system. This digital carrier system T1 employs PCM-encoded samples from 24 voice band channels for transmission over an optical fibre transmission line or single metallic wire pair. Every voice-band channel has a band width of about 300 Hz to 3000 Hz. Again, multiplexer is simply a digital switch with 24 independent inputs and one time division multiplexed output. PCM output signals from 24 voice-band channels are sequentially selected and connected through multiplexer to transmission line.
When a T1 carrier system, D-type (digital) channel banks perform sampling, multiplexing and encoding of 24 voice-band channels, every channel comprise an eight-bit PCM code and is sampled 8000 times a second. Every channel is sampled at the same rate. Figuredemonstrates the channel sampling sequence for a 24-channel T1 digital carrier system. As the Figureillustrates each channel is sampled once each frame though not at the same instance. Every channel's sample is offset from previous channel's sample by 1/24 of the total frame time. Hence one 64-kbps PCM-encoded sample is transmitted for every voice-band channel during each frame (a frame time of 1/8000 = 125 µs). Afterwards, an extra bit (known as the framing bit) is added to every frame. Framing bit occurs once per frame (8000-bps rate) and is recovered in the receiver, where it's used to maintain frame and sample synchronization between TDM receiver andtransmitter.
Find the minimum rate of sampling that must be used to convert the message into digital form: (a) If an audio message has a spectral extent of 3 kHz. (b) If a television sign
A capacitor is charged to 100 V and then discharged by a 50 kΩ resistor. If the time constant of the circuit is 0.8 s, verify: (a) The value of the capacitor, (b) The time
Ask q uestion #Minimum 100 words accepted#
Q. Determine the function of time for the clock? Given the block diagram for a 4-bit shift-left register shown in Figure (a), draw the output (Q 0 , Q 1 , Q 2 , Q 3 , and data
Example Register to Memory Example : Write assembly language statement to copy 25H stored in register D to memory location 3052H. Solution : Assuming 3050H is s
function of a commutator in a DC motor
Arithmetic Operations Various types of arithmetic operations like addition subtraction increment and decrement are performed in 8085 microprocessor. Generally in these ope
Q. ADMM (digital multimeter) reads true rms values of current. If the peak value of each of the following periodic current waves is 5 A, find the meter reading for: (a) a sine wave
Determine Total magnetic flux: A ring is composed of three sections. The cross-sectional area is 0.001 m2 for each section. The mean lengths of each section are l a = 0.3 m,
Working and block diagram
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd