Technology can be a mass noun, or a countable noun. There is a subtle difference.
As a mass noun, it refers to technology in the abstract. "5G technology", as a mass noun phrase, refers to all technology related to 5G as one collective abstract, or (depending on context) to some unspecified element of technology related to 5G.
As a countable noun, it refers to a discrete element of technology. For example, one 5G technology might be the so-called "Massive MIMO" antennae.
In practice, these will often be interchangeable, but there is a difference in meaning.
Oh, and whether or not you need an article depends on context. In both of your examples, there's no need for an article.