Noise in Information Communication

Shannon developed the famous information theory. In this theory, Shannon put forward an idea that noise is one of the necessary elements in the information communication. Shannon proved that we can reliably transmit units of information over noisy electrical channels. In the communication theory, noise refers to anything which blocks between message source and destination. It obstructed the process of coding and decoding information. Noise cannot be thoroughly avoided or eliminated, but it can be controlled or reduced as far as possible.

In the information communication, the exist of noise can lead to the inconsistency of information between source and destination. Therefore, the communication might be unsuccessful and the information might be untrue. Noise can be divided into the following categories. First is physical noise, such as the noise from external environment and the interference of the third when two are having communication, etc. The second noise is semantic noise. This is because message source and destination have different understanding of some terms and grammar which might lead to communication barriers. The third noise is because of the differences in social status, gender, occupation, economic level between message source and destination. This might cause interference and information distortion.

Here are a few examples of how noise works and generates:

  • Reading foreign novels. We will all read some classics. When the languages are not the same, we can only depend on translation. That is to say, the translators play the role of the middleman between the original authors and the audiences. He not only enables the communication but also more or less becomes the noise in the communication. The reading process is also a process of information communication. While reading foreign novels, the first kind of noise comes from the outside environment. If the audiences don’t read in a quiet environment, any other sound such as aircraft, car horns or human voice is the noise in the process of communication. Secondly, because the translator’s ability or background knowledge is different from the original author. His cognition of the author’s viewpoint is subjective. According to The Information Paradox, in the communication system, the information cannot be subjective. That is to say, the communication process is divided into two parts. First is between the author and the translator and the second is between the translator and the reader. The gap between the end of the first part and the beginning of the second part is closely related to the translator’s understanding of the author’s terms, grammar and so on. The third kind of noise is because of the readers’ social status, gender differences, etc. As the saying goes, there are a thousand Hamlets in a thousand people’s eyes. Different readers have different understandings about the same translation. After several noise disturbances, the information received by the audiences is not the same as that of the original authors.
  • Listening to music. The sounds that we recognize as a music genre also go through several layers of information processes. The digital audio file gets interpreted in software and hands off the information to a codec and those signals are sent to an electronic transducer, which converts digital binary information into a form of energy we can perceive and sound waves that play through the audio functions in our devices. In this process, there are several kinds of noise. One is the external noise as above. The second is from the noise of the devices. For example, the MP3 is too old, or the music is downloaded with HQ quality rather than SQ quality, which is nondestructive and will not cause other noise. Also, if audiences use headphone, the quality of the music is different from without using headphones. These are all the possibilities that will cause noise and affect the quality of the music. The third noise is because different audiences have different understanding of the same song. For example, for some special songs that are the singers sing for their fans. Fans of the singer and others will have different understanding of the same song, because their background knowledge of the singer is completely different. The biggest information that the singer add in the song might not transmit to those who don’t have the background knowledge of the singers.



  1. Denning, P. J., & Bell, T. (2012). The information paradox. American Scientist, 100(6), 470.
  2. Irvine, M. Introduction to the Technical Theory of Information.