Software Defined Radio Architecture MCQs on “Hardware Architecture – 2”.
1. ____ is used to optimize voltage standing wave ratio.
a) Antenna-matching unit
b) Radiating element
c) Antenna tuner
d) Power amplifier
Answer: c
Clarification: Antennas, operating over a wide frequency range, use antenna tuner to optimize the voltage standing wave ratio. It also results in improvement of radiation efficiency.
2. In ____ antenna, the interface boundary between radio and antenna is blurred.
a) multiple input multiple output
b) single input single output
c) single input multiple output
d) multiple input single output
Answer: a
Clarification: Wide bandwidth, large number of parallel receivers, and modem signal processing blur the interface boundary between radio and antenna in multiple input multiple output antennas.
3. Full duplex means _____
a) only transmission
b) only reception
c) transmission and reception but not at the same time
d) transmission and reception
Answer: d
Clarification: Full duplex means transmission and reception will be carried out simultaneously. Filtering may be done to prevent interference between high power transmission signal and low power received signal.
4. ____ filters can be used to aid full duplex communication.
a) Surface wave acoustic
b) Surface acoustic wave
c) Skin wave acoustic
d) Skin acoustic wave
Answer: b
Clarification: Full duplex means transmission and reception will be carried out simultaneously. Bulk acoustic wave filters, Surface acoustic wave filters, Yttrium-Iron-Garnet circulators are complex structures used to aid full duplex communication.
5. The dynamic range of signals during reception may be maximized by ____
a) frequency conversion
b) automatic gain control
c) frequency conversion and filtering
d) filtering
Answer: b
Clarification: The dynamic range of signals that can be processed at the receiver may be maximized by automatic gain control. Frequency conversion and filtering are done to minimize interference within the operating range of the radio.
6. The error corrected bits are ____ to complete the communication process.
a) grouped
b) re-transmitted
c) parsed
d) discarded
Answer: c
Clarification: The error corrected bits are parsed to identify the header, address, message, traffic, etc. The expected service is delivered to the user after being processed by various protocol layers.
7. The ____ are converted to ____ by ____ detector/demodulator combination.
a) bits, symbols, bit
b) symbols, bits, symbol
c) bits, symbols, symbol
d) symbols, bits, bit
Answer: b
Clarification: The symbols, obtained from down conversion process, are converted to bits by symbol detector/demodulation combination. Matched filter is an example for a detector.
8. Which among the following options have forward error correction integrated into the demodulation process?
a) Trellis code modulation
b) Soft decoding
c) Trellis code modulation and soft decoding
d) Block codes
Answer: a
Clarification: Forward error correction is carried out to reduce the number of bits received in error. It can be integrated into demodulation process such as in Trellis code modulation. It can be closely associated with demodulation process such as in soft decoding of convolution codes.
9. Which of the following is not included under MAC processing?
a) Framing
b) Frame synchronization
c) Error detection
d) IP addressing