Hi
If you had elaborated on the type of industry you are in, the location, the number of employees, the specific problem with communications (if you have a policy of encouraging people to speak in English and people are more free with their mother tongue etc.) perhaps we can revert with tailored solutions.
However for starters I would suggest the following
- Make induction compulsory and at each induction, have a policy that a different person from the functional departments will introduce the functional team and allied details to the new joiners.
- Encourage the departmental heads to interact more with the new joiners and to see that the new joiners are given assignments that will necessitate them to meet other departmental people and interact with them.
- Have some employee engagement activities that ate monitored to ensure that no set of people hog the center stage but everyone gets a fair chance to participate.
- You might also encourage activities like a weekly book review or a weekly review of movies/ economic news etc which will be allocated in turn to employees. Feedback on their contribution must be given so that they get both encouragement and learning points.
Best Wishes