Block Diagram Of A Communication System Computer Science Essay

Block Diagram Of A Communication System Computer Science Essay The doorway to the nowadays wireless communication systems was opened by Guglielmo Marconi when he transmitted the three-dot Morse code for alphabet ‘ S ‘ by the use of electromagnetic waves over a 3-KM link in 1895. This laid the foundation of modern communication systems ranging from broadcasting, satellite transmission and radio eventually progressing to nowadays cell phones. It wouldn’t be wrong to say that wireless communication has indeed revolutionized our present society A sudden increase has been observed in the expansion of radio systems during the last two decades. We have seen great evolution in Wireless communication systems from 1G narrowband analog systems in the 1980s to the 2G narrowband digital systems in the 1990s. Now the existing 3G wideband multimedia systems are being deployed. In the meantime, research and progress in the future-generation wideband multimedia radio systems is vigorously being pursued worldwide. To connect mobile users to th e public switched network the United States introduced first radiotelephone service by the end of the 1940s. Improved Mobile Telephone Service was launched by Bell Systems in 1960s due to which lots of improvements like direct dialing and increase in bandwidth took place. IMTS formed the bases of the first analog cellular systems. The term cellular was used due to the fact that coverage areas were split cells, they had a low power transmitter and receiver. BLOCK DIAGRAM OF A COMMUNICATION SYSTEM Figure 1. Block diagram of a general communication system. ANALOG vs. DIGITAL COMMUNICATION SYSTEMS Definition of Digital A method of storing, processing and transmitting information through the use of distinct electronic or optical pulses that represent the binary digits 0 and 1. Advantages of Digital low-priced reliable Easy to manipulate Flexible Compatible with other digital systems The information in digital form can only be transmitted without any degradation through a noisy channel In corporated networks Disadvantages of Digital Sampling Error As compared to analogue, larger bandwidth is required in digital communications for the transmission of the same information. Synchronization in the communications system is required to recognize the digital signals, but this is not the case with analogue systems. Definition of Analogue Analogue is a transmission standard that uses electrical impulses to emulate the audio waveform of sound. When you use a phone, the variations in your voice are transformed by a microphone into similar variations in an electrical signal and carried down the line to the exchange. Advantages of Analogue less bandwidth is required More Accurate Disadvantages of Analogue Signal loss and distortion can be seen due to the effects of random noise which is impossible to recover GENERATIONS OF CELLULAR SYSTEMS The concept of cellular telephony was introduced in AMPS, short for Advanced Mobile Phone Systems. AMPS divided the total area into small regi ons called cells and this was from where the concept of cellular telephony started. Cellular Systems had many advantages such as they increased quality, capacity, reliability and availability of mobile telephone network. The generations of cellular systems are described below. FIRST GENERATION CELLULAR SYSTEMS First generation cellular telephone systems were introduced in 1980’s. They were based on Analog Frequency Modulation technique. Each channel was assigned a sole frequency.