Telecommunication

Tellecommunication

TELECOMMUNICATION 1
Table of Contents
Question A: Layer One...........................................................................................................................2
Question C: data transmission: Error correction and multiplexing........................................................5
Question D: local and wide area networks............................................................................................8
Question F: OSI protocol stack listing..................................................................................................10
References...........................................................................................................................................11

TELECOMMUNICATION 2
Question A: Layer One
1. Amplitude modulation
The amplitude modulation is defined as the technique which is used in the field of
communication for improving the amplitude of the input signal. In such kind of
modulation technique, the input signal is multiplied with the large amplitude carrier
signal in order to enhance the amplitude level of the applied signal (Ozolins, et al.,
2017). Moreover, the amplitude of the carrier signal is varied in the proportion to the
message signal which is transmitted from the source. It is observed that the modulation
technique has the potential to provide the large amplitude signal which can improve the
strength of the signal and receiver can receive better output. The carrier signal is a
simple sine wave with a large amplitude which is mixed with the applied input message
signal. After multiplying the message signal with the carrier signal consumers can
improve the level of amplitude and transmitted from the transmitter system to receiver
(Paul, Bruce, & Roberts, 2017). It has been identified that the receiver gets the better
signals if the consumer uses the amplitude modulation technique and reduce the
distortion and noise from the signal. All these steps are used in the amplitude
modulation during data transmission and data is transmitted with the help of the
communication channel.
Figure: a carrier signal
(Source: Ryu, et al., 2015)
Figure: message signal

TELECOMMUNICATION 3
(Source: Ryu, et al., 2015)
Figure: AM-modulated signal
(Source: Ryu, et al., 2015)
2. Frequency modulation
The frequency modulation is a part of the modulation process that encodes the
information in the form of the carrier signal by changing the frequency value of the
input signal. Mainly, this process is used for the communication purpose and it
improves the level of frequency at the receiver side (Ryu, et al., 2015). The message
signal that has less frequency range is mixed with the carrier signal that has a large
frequency range and provides a modulated signal with better frequency. Moreover, the
applied signal is combined with the high level frequency which is called as the carrier
wave and the communication channel is used for data transmission. in which the source
produce the information or input signal and passed through the transducer which
provides the signal in the form of electrical waves (Silveri, Tuorila, Thuneberg, &
Paraoanu, 2017). The input signal is multiplied with the carrier signal and passed
through the buffer amplified for improving the frequency of the message signal. At the
receiver side, a demodulator circuit is used in order to convert the modulated signal in
the original form and receiver get better results by using this technique.
3. Types of layer one media
Type of layer one media Environments Reason