The law does not make any specific references to satellite dishes. However, if the installation of the dish has resulted in damages to your property, you have the right to claim that from the tenant, especially if they did this without your knowledge. If you cannot come to a resolution with the tenants then legally you could serve the tenants with an N5 Form, Notice to Terminate a Tenancy based on the damages, and apply to the Landlord and Tenant Board for a decision on the issue.