Introduction to Analog Communication

Communication is the process of establishing a connection or link between two or more points for the exchange of information. Analog communication had a significant need for centuries as it has been a fundamental need of human interaction, which allows anyone with the continuous transfer of signals along with information. Let's explore the basic principles, essential terminologies, applications, advantages, and limitations of analog communications in this article.

Whoever wants to understand how these communications systems work then it is required to first understand the fundamentals of analog communications. As we have seen a vast development of digital communications, still analog communications are very beneficial in almost every sector as everything around us is in analog form, including television, radio, broadcasting equipment, and telecommunications.

What is Analog Communication ?

Analog communication is simply defined as the method of sending or receiving and other processing of data with the help of using continuous signals also known as analog signals. These analog signals could represent many things such as image, voice, video, or any other form of data but the content is linear as well as static not dynamic.

There are so many real-life examples available in the real world such as speaking with someone over the phone or using a switch to control a bulb or something else, microwaves, etc. These are a few examples of analog communications.

What is Communication?

As we understand that the Communication is simply the basic process of exchanging information. The electrical devices which are used for communication purposes are known as communication equipments. Different types of communication equipments when assembled together form a communication system.

Analog communication involves the transmission of information using continuous signals that vary in amplitude, frequency, or phase to represent data. Unlike digital communication, which discretizes data into binary code, analog communication maintains the original form of the signal throughout transmission.

Key Terms of Communication

Lets see some key terminologies which will help us to understand the concept better.

• Amplitude: The strength or magnitude of a signal, often representing the loudness or intensity of sound in audio communication. It refers to the greatest deviation from equilibrium that an item in periodic motion might display.
• Frequency: The rate at which a signal oscillates, determining the pitch of sound or the channel bandwidth in radio communication. Also frequency is the number of times an alternating current (AC) switches between positive and negative in a unit time.
• Modulation: It is a conversion process used to improve the signals generated from different info sources as they are not always suitable for direct transmission.
• Demodulation: It is an opposite of Modulation as we can define it as the process of reverse conversion for getting the original information or required signal from a modulated carrier signal.
• Noise: Noise can be defined as the unwanted signal that comes along with the message signal and carrier which affects the clarity and reliability of communication.

What is Signal?

Signal can be defined basically as a physical quantity that varies with time with respect to electronics it can be said that the electrical signal is a representation of the physical quantities such as current and voltage with respect to the time. for example our heart continuously generates a electrical impulse and it can be measured using the ECG machine used by doctors which generates the graph for the impulse generated with respect to time and it is known as signal.

Types of Signals

There could be many different types of signals depending upon the application lets have some look over some of them :

• Analog Signal: A signal is called analog if it can take any value on y-axis or amplitude axis at every time that's why its also known as Continuous signal , it has low bandwidth and slow transmission. It has high error rate and high distortions, eg- voltage, current, sound waves, etc.
• Digital Signals: A digital or discrete signal can be defined as signal which can take only infinite no. of value on y-axis. It is not continuous on x-axis. It can be defined at discrete intervals of time that's why its also called discrete signal, here time is discrete but the amplitude is continuous. for eg- Digital audio, digital image etc.
• Periodic Signals: A signal x(t) is said to be periodic if it satisfies the condition x(t)=x(t+T). We can also say that the periodic signals are those signals which repeat itself again and again for a regular interval of time. for eg- any signal waves like sine waves, square waves etc.
• Aperiodic Signals: The signal which does not has a regular or repetitive pattern at intervals of time is known as aperiodic signal for eg- random noise, impulsive signals etc.
• Even signal: A signal which is symmetrical along the vertical axis or time origin is known as even signal it is also known as the symmetrical signals, for eg- cosine wave signal etc.
• Odd signal: A signal that is anti symmetrical about the vertical axis is known as odd signal also known as asymmetrical signals. for eg- sine wave signal etc.

Analog Communication System

The communication system is a combination of some electrical components and devices which combine together and allows the transmission of data and other information between two or more points.

Functions of Communication System

• Transmitter: A transmitter is an device which is used for transmission of signal in the communication channel. It includes many other processes like encoding, modulation, and amplification etc, basically it transmits the input data to the communication channel and its receiver.
• Receiver: The receiver is like a opposite of the transmitter as it receives the transmitted signal across the communication channel and then it processes it to extract the original message or information. This process includes many stages such as demodulation, decoding, and sometimes amplification to amplify or enhance the quality of the signal received.
• Channel: The channel is the path or we can say medium through which the signal or the information being transmitted travels from the transmitter to the receiver. A channel could be wired such cables or optical fibers or wireless like radio waves or microwaves. During this time some noise get into it and cause many disturbances to the signal, its noise and some distortion in signal which should be reduced or eliminated for successful transmission.
• Encoder: Encoders are used for the process of encoding the original signal in simple words we can say that encoders are used to convert the message or information into a format which is suitable for transmission through the chosen communication channel, it is known as encoding of message.
• Decoder: Decoders are the opposite of encoders, they are useful at the receiving end to reverse the encoding process and get the original message from the received encoded signal by extracting from it, this process is known as decoding we get the original message by the end.

Analog Vs Digital Communication

As we see nowadays that more modern electrical devices are became digital by definition as opposed to analog

Advantages

Here we will see the advantages of analog communications given below :

• Simplicity: Analog communication systems are often simpler to design and implement compared to digital systems.
• Signal Transfer is smooth: Analog signals maintain continuity, resulting in smooth transmission without quantization noise.
• Cost effective: Analog communications are more cost effective as compared to digital communication
• High Stability and consistency: Analog communication is old technology but still unreplaceable in many cases therefore many old systems and devices still rely on analog communication, ensuring their backward compatibility.

Disadvantages

Here we will see the disadvantages of analog communications given below :

• Vulnerable to noise: It has been seen that the digital communication being the latest version in the industry is more immune to noise as compared to the analog communication methods.
• Limited bandwidth: Analog Communications are limited to some range of applications.
• Weakening of signal over distance: Due to dependency on analog signals they might get weak due to disturbances or noise along the path for long distances.
• Inflexible in signal processing: Analog communications are inflexible for the purpose of signal processing as compared to digital signals
• Limited error detection and correction: We can not detect much error while analog process and less correction as compared to digital communication.

Applications

Applications of Analog communications are mentioned below :

• Broadcasting of media: The broadcasting process of Radio and television shows are possible with the help of Analog communications where the Amplitude Modulation (AM) and Frequency Modulation (FM) techniques are used for the transmission of the audio and video signals.
• Analog communication is the very important for Telecommunications: Analog telephone systems for the telephonic communication. It was the backbone for communication over long distances.
• In the Instrumentation process the analog communication is very useful: As we know that the analog sensors and transducers which are used for the measuring of physical quantities and its conversion to the signals in analog form.
• Music studios and production: Analog devices which are commonly used in many devices such as audio recorders, mics, speakers, amplifiers and other devices are used.

Conclusion

We can conclude that the analog communication remains a very important component of modern communication systems, which offers simplicity, compatibility, and smooth transmission of signal. Despite the development of digital technology, analog communications continues to be widely used for industrial and technical applications, indicating its long-term importance.

Understanding the fundamentals and details of analog communications is essential for engineers and enthusiasts working in the constantly changing world of communications technologies. As we mark the progress of the digital age, let us also keep in mind the classic beauty and utility of analog communications.