Previous year question paper for CS2 (Diploma Electronics & Communication Engineering 5th)

1. Introduction: (02hrs)

Basic block diagram of digital and data communication systems. Their

comparison with analog communication systems.

2. Coding (06hrs)

a) Introduction to various common codes 5 bit Baudot code, 7 bit

ASCII,ARQ, EBCDIC

b) Code error detection and correction techniques - Redundancy,

parity,block check character (BCC), Vertical Redundancy check

(VRC),Longitudinal Redundancy Check (LRC), Cyclic Redundancy

check(CRC), Hamming code

3. Digital Modulation Techniques: (08hrs)

a) Basic block diagram and principle of working of the following:

-Amplitude shift keying (ASK): Interrupted continuous wave (ICW), two

tone modulation

- Frequency Shift keying (FSK)

- Phase shift keying (PSK)

4.Data Transmission:

Characteristics/working of data transmission circuits;

band width requirements, data transmission speeds, noise, cross talk,

echo suppressors, distortion, equalizers. (06 hrs)

5. UART, USART:-

- Principle of operation of UART, USART

- Need and function in communication systems (06 hrs)

6. Modems: (06hrs)

Need and function of modems, Mode of modems operation (low speed,

medium speed and high speed modems). Modem interconnection, Modem

data transmission speed, Modem modulation method, Mode minter

facing (RS 232 Interface, other interfaces).

7. Telemetry: (06 hrs)

Radio-telemetry, and its application. Block diagram of TDM and FDM

telemetry system.

8. Electronic Exchange: (08hrs)

8.1 Typical telephone network. Various switching offices (Regional Centre,

District Centre, Toll Centre, Local Office) and their hierarchy.

8.2 Principles of space division switches. Basic block diagram of a digital

exchange and its working.

8.3 Combined space and time switching: Working principle of STS and TST

switches.

8.4 Functions of the control system of an automatic exchange. Stored

programme Control (SPC) processor and its application in electronic

exchange and rural telephone exchange.

8.5 Introduction to PBX, PABX and EPABX. Function of PBX. PABX relation

with central office. Modern PABX capabilities

9. Operation of Cellular Mobile Telephone System. (06hrs)

Concept of cells and frequency reuse. Special features of cellular mobile

telephone. Block diagram of Mobile phone and its working.

10. Facsimile (FAX) (02hrs)

Basic idea of FAX system and its applications. Principle of operation and

block diagram of modern FAX system. Important features of modern FAX

machines