MCQ ( UNIT 3 REVISION)

The transmission mode that supports two way simultaneous transmission between two stations

• Simplex

• Full Duplex

• Half duplex

• Full/full duplex

Pulse Time Modulation means

• PAM and PCM

• PAM and PPM

• PWM and PPM

• PCM and PPM

The type of parity generally used in VRC and LRC respectively

• Odd and even

• Even and even

• Odd and odd

• Even and odd

The 8 bit fixed length code developed by IBM

• ASCII code

• Boudot code

• EBCDIC code

• Unicode

More than one consecutive bits in the data frame unit have corrupted in reception

• Data error

• Burst error

• Single error

• Multiple error

Which of the following is used for error correction

• FEC

• LRC

• VRC

• CRC

Checksum is used for

• Error detection

• Error correction

• Error detection &correction

• Encryption

The Telex code is fixed length character code also called as

• ASCII code

• Boudot code

• EBCDIC code

• Unicode

In a communication system a device which converts voltage variations to field variations and vice versa is

• Channel

• Antenna

• Modulator

• Demodulator

The phenomenon where by the higher components of signal x(t) reappears as low frequency components in the spectrum of the sampled version of x(t) is

• Sampling

• Quantization

• Aliasing

• Encoding