A music recorded at a studio is to be transmitted over a distance of 100 km using a wireless digital transmission system
Posted: Wed Apr 27, 2022 6:15 pm
A music recorded at a studio is to be transmitted over a
distance of 100 km using a wireless digital transmission system.
The signal X (t) = 2 Sin (300πt) is produced by an electronic
musical instrument. This signal is first captured by a microphone
(i.e., transducer), which converts the signal into an electric
signal at the same frequency but at an amplified amplitude of +5/-5
V. The electrical signal then enters the transmitter of the
communication system. Here, the incoming signal is first digitized
using a 3 bit Analogue to Digital Converter. The digitized signal
is then encoded with Unipolar NRZ coding technique having a maximum
voltage level of +2V. Next, the digital data signal is modulated
with a carrier frequency of 3 GHz using Amplitude Shift Keying
(ASK) technique. The maximum amplitude of the modulated signal is
+5V. The signal is then transmitted using wireless media. The
wireless channel has an SNR threshold of 30 dB and a maximum
bandwidth of 22 MHz. A half-wave dipole (i.e., Omni-directional)
antenna is used as the transmission media. Due to external noise
and atmospheric conditions, the transmitted signal gets attenuated
and unwanted frequencies gets added to the signal.
B. With reference to the encoded signal, explain the drawbacks
of Unipolar NRZ and suggest a method to overcome them
distance of 100 km using a wireless digital transmission system.
The signal X (t) = 2 Sin (300πt) is produced by an electronic
musical instrument. This signal is first captured by a microphone
(i.e., transducer), which converts the signal into an electric
signal at the same frequency but at an amplified amplitude of +5/-5
V. The electrical signal then enters the transmitter of the
communication system. Here, the incoming signal is first digitized
using a 3 bit Analogue to Digital Converter. The digitized signal
is then encoded with Unipolar NRZ coding technique having a maximum
voltage level of +2V. Next, the digital data signal is modulated
with a carrier frequency of 3 GHz using Amplitude Shift Keying
(ASK) technique. The maximum amplitude of the modulated signal is
+5V. The signal is then transmitted using wireless media. The
wireless channel has an SNR threshold of 30 dB and a maximum
bandwidth of 22 MHz. A half-wave dipole (i.e., Omni-directional)
antenna is used as the transmission media. Due to external noise
and atmospheric conditions, the transmitted signal gets attenuated
and unwanted frequencies gets added to the signal.
B. With reference to the encoded signal, explain the drawbacks
of Unipolar NRZ and suggest a method to overcome them