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 numbering plan is achieved in modern telephony?
Ans:
The purpose of numbering plan is to uniquely identify every subscriber connected to a telecommunication network. A numbering plan may be closed, semi open or open. An open-numbering plan permits wide variation in the number of digits to be used to identify a subscriber within a multi exchange area or within a country. This plan is used in nations equipped extensively with non-Director Strowger switching systems. In such cases numbering scheme is generally an exact image of network structure changes. A semi-open plan permits number lengths to differ by almost one or two digits. Today, this technique is the most common and is used in many countries. In closed numbering plan or Uniform numbering scheme, number of digits in a subscriber number is fixed. A world numbering plan or international numbering plan has been defined by CCITT in its recommendations E.160-E.163. For numbering purposes, world is divided into zones as displayed in figure. Every zone is given a single digit code. For European zone two codes have been allotted due to large number of countries within this zone. Each international telephone number comprises two parts as demonstrated in figure. Country code contains one, two or three digits, first digit being the zone code in which the country lies. In cases where an integrated numbering plan already covers an entire zone, countries in that zone are identified by single digit zone code itself.
Existence of world numbering plan places restriction on the national numbering plan of each country. Number of digits in an international subscriber number is limited to an absolute maximum of 12. In practical, with a few exceptions, world numbers are limited to 11 digits. As a result, number of digits available for a national numbering plan is 11-N, where N is number of digits in country code.
Generally a national number comprises three parts as demonstrated in figure. Area or trunk code identify a particular numbering area or multi exchange area of the called subscriber and thus determine routing for a trunk call and a charge for it. According to CCITT international usage, a numbering area is identified as that area in that any two subscriber use identical dialling procedure to reach other subscriber in the network. An exchange code identifies a specific exchange within a numbering area. It determine routing for incoming trunk call from another numbering area or for a call originating from one exchange and destined to another one in same numbering area. Subscriber line number is used to select called subscriber line at terminating exchange. In CCITT terminology, combination of exchange code and subscriber line number is called the subscriber number which is number listed in the telephone directory.
Question 1 (a) Describe the functions of the modulator and source encoder in a digital communications system. (b) By using appropriate examples, distinguish between th
Q. Effect of feedback on dynamic response and bandwidth? Let us consider the block-diagram representation of the open-loop system shown in Figure 16.2.5(a), whose direct transf
Q. What is the need of the resistance used in a clipper? Resistor is used in a clipper to limit the current through the diode. To avoid the damage due to excessive current thro
Insulators have (A) A full valence band. (B) An empty conduction band. (C) A large energy gap. (D)All the above. Ans: Insulators have a large energy gap.
Voltage Quadrupler : A voltage quadrupler circuit is shown in fig. which provides output voltage V0 = 4 Vm. Operation : Capacitor C 1 , C 2 and C 3 charges to Vm, 2Vm and 2Vm
Chopper Configuration Chopper are classified in five different classes according to their operating capability in particular quadrant. The current directions and voltage
analysis and detail working of bootstrap sweep circuit
Q. Define Resistance in lumped-circuit? An ideal resistor is a circuit element with the property that the current through it is linearly proportional to the potential differenc
Design and using Pspice, evaluate a single-stage transistor amplifier amplifier to meet the following specifications: * Power supply - 12V dc. · *Voltage gain - 120 when Vin
Q. Let a(t) = [1 + m A x(t)] and x(t) = cos 2πf m t, f m c , and x c (t) = A(t) cos 2πfct . (a) With m A =1, sketch one full period of the AM wave and draw the envelope by co
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