Is communication a circular process

Whether or not communication is a circular process depends on which model of communication best fits the particular communicative act you are discussing.

One of the earliest communication models is the Shannon-Weaver model, which is linear; a message is sent through a channel to a recipient, who does not provide any feedback. Obviously, this means that the communication is not circular. An example of this would be most televised broadcasts, like the president's speeches, as the viewer has few opportunities to provide feedback.

Later models of communication, however, added a mechanism for recipient feedback. In what is known as the transactional or circular model of communication, the receiver and recipient both send and receive messages, leading to both parties being renamed sender-receivers. This is a circular model of communication. An example of this is most interpersonal, face-to-face communication. You receive feedback from your conversation partner through their body language and verbal responses and so adjust your messages to fit that; your partner does the same.

Today, most communication tends to be seen as transactional, meaning that it is circular.