Wireless Communication

A periodic signal is always:

• a.Could be either analogue or digital.

• b.Both analogue and digital.

• c.Digital.

• d.Analogue.

A signal is periodic when:

• The same signal pattern repeats every 1 second.

• The same signal pattern repeats every 1 Hz.

• The same signal pattern repeats over time.

• The same signal pattern repeats over frequency.

Assuming two level signalling, what is the channel capacity if its frequency range is 100-400Hz according to Nyquist’s capacity measure in a noise free channel?

• 300bps.

• 600bps

• 500bps.

• 300Hz.

• 500Hz.

Select 3 of the below options that can describe a digital signal.

• The signal may be discontinuous

• The signal is discontinuous

• The signal intensity maintains a constant value for some period of time.

• The signal may be discrete.

• The signal is discrete.

If the signal over noise ratio (S/N) is equal to 1000 what is the SNR in dB?

• None of the above

• 20

• 40

• 30

Which one of the following cases is Digital data to digital signal?

• Computer communication using telephone line

• Computer communication using ISDN.

• Home telephone system.

• Digital mobile communication system

According to Shannon what is the formula to calculate the channel maximum capacity on a noisy channel in bps (where C the channel capacity in bps and B the channel bandwidth in Hz)?

• C = SNRlog2(1+B).

• C = Blog2(SNR+1).

• C = SNRlog10(1+B).

• C = Blog2(SNR).

Select 3 of the below signals you think are analogue.

• Voice

• Pressure

• Video

• .ASCII code

Wave length is measured in

• Hz

• Cycles per metre

• Metres

• Seconds

Which of the following are key factors that affect the transmission in any wireless communication system? (Multiple answers).

• Attenuation

• Delay distortion

• Signal power

• Interference