








Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Community
Ask the community for help and clear up your study doubts
Discover the best universities in your country according to Docsity users
Free resources
Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors
HERE IS SOME QUESTIONS LISTED BELOW AND ANSWERS IN THIS ATTACHED PDF 1 . what is meant by data communication and explain its characteristics. 2.WRITE A BOUT DIFFERENT TRANSMISSION MODES. 3.explain different digital t o analog conversion techniques. 4. explain different ANALOG to analog conversion techniques
Typology: Assignments
1 / 14
This page cannot be seen from the preview
Don't miss anything!
Only when communicating devices are part of a hardware and software-based communication system do data communications occur. In a computer, Data communication allows electronic or digital data to be sent between two or more devices regardless of
their geographical location, transmission medium, or data substance. The message, sender, receiver, transmission medium, and protocol are all crucial elements in data communication. ⦿ Characteristics of Data Communication Data communication has four critical characteristics that are as follows:
2. Half-Duplex Mode – In half-duplex mode, each station can both transmit and receive, but not at the same time. When one device is sending, the other can only receive, and vice versa. The half-duplex mode is used in cases where there is no need for communication in both directions at the same time. The entire capacity of the channel can be utilized for each direction. Example: Walkie-talkie in which message is sent one at a time and messages are sent in both directions. Channel capacity=Bandwidth * Propagation Delay
3. Full-Duplex Mode – In full-duplex mode, both stations can transmit and receive simultaneously. In full_duplex mode, signals going in one direction share the capacity of the link with signals going in another direction, this sharing can occur in two ways: - Either the link must contain two physically separate transmission paths, one for sending and the other for receiving. - Or the capacity is divided between signals traveling in both directions. Full-duplex mode is used when communication in both directions is required all the time. The capacity of the channel, however, must be divided between the two directions. Example: Telephone Network in which there is communication between two persons by a telephone line, through which both can talk and listen at the same time. Channel Capacity=2* Bandwidth*propagation Delay
This technique uses two frequencies, f1 and f2. One of them, for example f1, is chosen to represent binary digit 1 and the other one is used to represent binary digit 0. Both amplitude and phase of the carrier wave are kept intact.
Analog-to-Analog Conversion Analog signals are modified to represent analog data. This conversion is also known as Analog Modulation. Analog modulation is required when bandpass is used. Analog to analog conversion can be done in three ways:
Amplitude modulation is implemented by means of a multiplier. The amplitude of modulating signal (analog data) is multiplied by the amplitude of carrier frequency, which then reflects analog data. The frequency and phase of carrier signal remain unchanged.
In the modulation technique, the phase of carrier signal is modulated in order to reflect the change in voltage (amplitude) of analog data signal. Phase modulation is practically similar to Frequency Modulation, but in Phase modulation frequency of the carrier signal is not increased. Frequency of carrier is signal is changed (made dense and sparse) to reflect voltage change in the amplitude of modulating signal